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Identifying the Sun’s Siblings

With TESS going into a 60-day period of calibration and testing, I’ll turn this morning to a different kind of survey. GALAH is an acronym for Galactic Archaeology, a term I’ve generally associated with so-called Dysonian SETI, where data is mined in a search for signs of advanced engineering or any anomalies that could signify an extraterrestrial civilization at work. But GALAH has a different object: It has examined some 340,000 stars enroute to 1 million.

A just published paper on GALAH states the goal succinctly:

The overarching goal of the GALAH survey is to acquire high-resolution spectra of a million stars for chemical tagging, in order to investigate the assembly history of the Galaxy.

The survey was launched in 2013 as a deep study of galactic formation and evolution, using the HERMES spectrograph at the Australian Astronomical Observatory’s 3.9-meter Anglo-Australian Telescope near Coonabarabran, NSW. Now coming online is a major data release, the second from GALAH, that has interesting implications not only for the broad field of galactic evolution but also the history of our own Sun. Thus Gayandhi De Silva (University of Sydney and AAO), who oversaw the work on Hermes and coordinated the effort leading to the release:

“No other survey has been able to measure as many elements for as many stars as GALAH. This data will enable such discoveries as the original star clusters of the Galaxy, including the Sun’s birth cluster and solar siblings — there is no other dataset like this ever collected anywhere else in the world.”

Image: A schematic of the HERMES instrument showing the path of star light from the telescope and demonstrating how it is split into four different channels. Credit: AAO.

Our recent look at the possibility of a prior civilization on our own planet is now superseded by a quest to dig much further back in time. Finding the Sun’s birth cluster leverages the fact that stars from the same originating cluster should have the same chemical composition. The problem is that clusters within the Milky Way are quickly pulled apart and are scattered. GALAH is looking to match compositional traits — the researchers call this the stars’ DNA — to parse for each star about two dozen chemical elements like oxygen, aluminium and iron.

So the day may come when we can point to stars that were born in the same cluster as the Sun. While an hour is needed to collect enough photons of light from each of the stars in the GALAH survey, the project is able to observe 360 stars at the same time, an effort that so far has involved more than 280 nights at the AAO instrument since 2014 for data collection. The HERMES spectrograph was designed by the AAO specifically for the GALAH survey.

At work here is computer code that PhD student Sven Buder, lead author of a paper on the data release, calls ‘The Cannon,’ a nod to astronomer Annie Jump Cannon, whose work on stellar spectra of several hundred thousand stars in the early 20th Century was groundbreaking. Says Buder:

“We train The Cannon to recognize patterns in the spectra of a subset of stars that we have analysed very carefully, and then use The Cannon’s machine learning algorithms to determine the amount of each element for all of the 340,000 stars.“

Image: Hubble has captured the most detailed image to date of the open star cluster NGC 265 in the Small Magellanic Cloud. The image taken with the Advanced Camera for Surveys onboard the NASA/ESA Hubble Space Telescope show a myriad of stars in crystal clear detail. The brilliant open star cluster, NGC 265, is located about 200,000 light-years away and is roughly 65 light-years across. Our investigations into open clusters like this may help us learn more about our Sun’s birth. Credit: ESA / NASA / E. Olszewski (University of Arizona).

Be aware that on the 25th of this month, the European Gaia satellite will likewise offer a major data release. Gaia, with its mapping of more than 1.6 billion stars in our galaxy, will mesh with the GALAH findings, using the latter’s calculations of stellar velocities to interpret Gaia data in what is becoming the most accurate atlas of the night sky ever available. From the paper:

The stellar parameter and abundance information contained in GALAH DR2 [Data Release 2] will enable major steps forward in Galactic Archaeology, including detailed work to identify clusters within the chemical space and characterize its structure and dimensionality. In combination with the dynamical information provided by Gaia DR2, we will work toward a reliable narrative of how the Milky Way was assembled and how it has evolved since, using chemodynamics and chemical tagging.

Incorporating parallax information from GAIA and broadening GALAH toward the target of one million stars is the task that lies ahead for the researchers, who plan subsequent data releases with re-analyses of all the stars from DR2 and the new stars subsequently observed.

The overview paper on GALAH, one of eleven science papers that will accompany the data release, is Buder, “The GALAH Survey: Second Data Release,” Monthly Notices of the Royal Astronomical Society Volume 476, Issue 4 (1 June 2018), pp. 5216–5232 (abstract / preprint).

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TESS: Magnifique!

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Civilization Before Homo Sapiens?

My doctor is a long-time friend who always stops during my annual physical to ask about what’s going on in the hunt for exoplanets. Last week he surprised me when, after I had described ways of analyzing a transiting planet’s atmosphere, he asked whether planets could give rise to civilizations in different epochs. Why just one, in other words, given that homo sapiens has only been around for several hundred thousand years? Our technological civilization is a very recent, and to this point a short-lived phenomenon. Were there others?

I was startled because Adam Frank (University of Rochester) and Gavin Schmidt (NASA Goddard Institute for Space Studies) have recently raised a stir with a paper on what they call the ‘Silurian Hypothesis,’ the name deriving from a Doctor Who TV episode referencing intelligent reptiles called Silurians who come to life when accidentally awakened. As the authors point out in their paper:

We are not however suggesting that intelligent reptiles actually existed in the Silurian age, nor that experimental nuclear physics is liable to wake them from hibernation. Other authors have dealt with this possibility in various incarnations (for instance, Hogan (1977), but it is a rarer theme than we initially assumed.

True enough, although it does pop up in science fiction from time to time. I’m remembering a 1989 tale from Barry Longyear that involved a fleet of starships returning to their home world to find that it is now being managed by humans. The starship crews — essentially intelligent dinosaurs — have been gone 70 million years, their civilization long obliterated on their home world. The novel Frank and Schmidt reference is James Hogan’s Inherit the Stars, in which evidence of an unknown early human technology is found on the Moon. Maybe readers can supply some other stories involving civilizations from deep time.

Digging Out the Evidence

Frank comes to this topic as a natural outgrowth, I think, of his earlier investigations of how industrial civilizations affect their home planets. All this involves issues of sustainability and climate alteration, using dynamical systems theory as a methodology to examine how species with energy-intensive technology alter planetary evolution (you can read more about this in my Astrobiology and Sustainability). Does an industrial civilization invariably cause detectable climate shift? Gavin Schmidt jogged Frank’s thinking on the topic by bringing up the question of prior civilizations, which raised the issue of just how we might detect such a culture.

Image: The inland seas in North America (Western Interior Seaway) and Europe had receded by the beginning of the Paleocene, making way for new land-based flora and fauna. If an early mammal had produced a civilization in this era, would we be able to find traces of it? Credit: Paleontology World.

We’re talking non-human cultures if we go back far enough, and with the passage of hundreds of millions of years, evidence becomes more than a little problematic. Frank has just written a piece for The Atlantic that pulls out the major themes of the paper. Was There a Civilization On Earth Before Humans? puts the matter succinctly. Because when you talk about direct evidence of an industrial civilization, we’re dealing with a geologic record that makes it all but impossible to probe past the Quaternary period, some 2.6 million years ago.

We can obviously study earlier eras, but as the authors point out, the largest extant surface area is in the Negev Desert, in southern Israel, which can take us back 1.8 million years. Earlier than the Quaternary, we rely on exposed surfaces unearthed through excavation, drilling or mining, while our study of ocean sediments faces the fact of recycling ocean crust, so that our evidence is for periods that post-date the Jurassic; i.e., we can go back some 170 million years.

This gets seriously intriguing, and I found myself reading The Atlantic piece and the original paper (citation below) with a compulsive fascination, maybe because when I was a kid, I used to think about becoming a paleontologist, digging up the remains of creatures from the days of the brontosaurus. But how much of that past world can we recover given how sparse the fossil record is? For Frank and Schmidt point out how little of life is captured this way. From the paper;

The fraction of life that gets fossilized is always extremely small and varies widely as a function of time, habitat and degree of soft tissue versus hard shells or bones (Behrensmeyer et al., 2000). Fossilization rates are very low in tropical, forested environments, but are higher in arid environments and fluvial systems. As an example, for all the dinosaurs that ever lived, there are only a few thousand near-complete specimens, or equivalently only a handful of individual animals across thousands of taxa per 100,000 years. Given the rate of new discovery of taxa of this age, it is clear that species as short-lived as Homo Sapiens (so far) might not be represented in the existing fossil record at all.

The survival of actual objects produced by such a civilization — think the Antikythera Mechanism from ancient Greece — is unlikely indeed. Our species has left countless artifacts that have yet to be recovered, if they ever will be. On a wider scale, we are learning much about detecting the effects of civilizations on the landscapes around them (here I think of aerial surveys finding building sites or burial mounds), but Frank and Schmidt note that the current rate of urbanization is less than one percent of the Earth’s surface. We don’t know where to look, and the likelihood of finding direct evidence of artifacts is remote in the extreme.

Would we know it, then, if an early mammal built a civilization in the Paleocene (60 million years ago)? Let’s assume a civilization lasting no more than 100,000 years, which turns out to be 500 times longer than our own civilization to this point. You would think that specific markers of industrial acthttps://arxiv.org/abs/1804.03748ivity would get through — these would include, perhaps, plastics, which seem to live forever. They do break down eventually, as the authors note, but the results are unclear:

The densification of small plastic particles by fouling organisms, ingestion and incorporation into organic ‘rains‘ that sink to the seafloor is an effective delivery mechanism to the seafloor, leading to increasing accumulation in ocean sediment where degradation rates are much slower (Andrady, 2015). Once in the sediment, microbial activity is a possible degradation pathway (Shah et al., 2008) but rates are sensitive to oxygen availability and suitable microbial communities. As above, the ultimate long-term fate of these plastics in sediment is unclear, but the potential for very long term persistence and detectability is high.

We might likewise find evidence like increased concentrations of metals. Maybe our relentless production of electronics will leave a trace in the concentration of rare-Earth elements in sediments for some successor species to identify. Of course, we can’t be comfortable about generalizing from our own activities to those of some hypothetical primeval civilization, but there is room for speculation nonetheless, and Frank and Schmidt look hard at fossil fuels, the burning of which releases carbon into the atmosphere, causing the balance of carbon isotopes to shift in what atmospheric scientists call the ‘Suess effect,’ a change in isotope ratios of carbon that is readily traced in the last century.

We do see ‘spikes’ in the geological record, though none that are ‘spiky enough’ to fit into the hypothesis of a Silurian civilization. Using our own ‘Anthropocene’ era as a guide, we are seeing a huge increase in atmospheric carbon levels much unlike the slower spikes of the Paleocene-Eocene Thermal Maximum (PETM), when the planet’s average temperature rose well above what we have today. Those much earlier spikes (56 million years ago) took hundreds of thousands of years to play out. A civilization’s signal in terms of carbon output is, at least judging from our own, much more sudden, though we have yet to learn how it will end.

We can’t rule out detection methods that could trace extremely short-lived events in ancient sediments, the authors conclude, but they would be extraordinarily hard to detect. Frank and Schmidt don’t believe any such civilization existed, but their paper asks a broader question that is relevant to exoplanet studies. What kind of effects does the collection of energy for building a civilization leave on its home world? Assuming there is feedback into planetary systems, we may be able to build a set of markers that could help us identify the process at work.

As Frank concludes in his Atlantic essay:

…our work also opened up the speculative possibility that some planets might have fossil-fuel-driven cycles of civilization building and collapse. If a civilization uses fossil fuels, the climate change they trigger can lead to a large decrease in ocean oxygen levels. These low oxygen levels (called ocean anoxia) help trigger the conditions needed for making fossil fuels like oil and coal in the first place. In this way, a civilization and its demise might sow the seed for new civilizations in the future.

Cycles of civilizations could thus occur, even if we have no evidence that they have previously taken place on Earth. The broader question is whether we can deduce a set of maxims telling us how biospheres evolve, and how the activities of their societies re-shape their world. Again we are seeding the debate over differing kinds of biosignatures and technosignatures that will inform our studies of the data gathered by the next generation of space and ground instruments.

The paper is Schmidt and Frank, “The Silurian Hypothesis: Would it be possible to detect an industrial civilization in the geological record?” published online by the International Journal of Astrobiology 16 April 2018 (abstract / preprint).

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A Deeper Look at TESS

The launch of TESS aboard a SpaceX Falcon 9 looks to be on track for Wednesday after yesterday’s delay, which the company attributed to the need for “additional GNC [guidance, navigation and control] analysis.” So we wait just a bit more, knowing that the payoff justifies the caution. We should be identifying planets in the thousands, and around bright, nearby stars.

Principal investigator George Ricker and team have been through the process of designing, building and launching a mission before. It was in 2000 that NASA launched the MIT-built High Energy Transient Explorer 2, or HETE-2, that studied gamma-ray bursts for seven years in Earth orbit. A key technology for HETE-2 was the CCD — charge-coupled device — which allowed the satellite’s optical and X-ray cameras to record bursts in electronic format.

“With the advent of CCDs in the 1970s, you had this fantastic device … which made a lot of things easier for astronomers,” says HETE-2 team member Joel Villasenor, who is now also instrument scientist for TESS. “You just sum up all the pixels on a CCD, which gives you the intensity, or magnitude, of light. So CCDs really broke things open for astronomy.”

Image: A set of flight camera electronics on one of the TESS cameras, developed by the MIT Kavli Institute for Astrophysics and Space Research (MKI), will transmit exoplanet data from the camera to a computer aboard the spacecraft that will process it before transmitting it back to scientists on Earth. Credit: MIT Kavli Institute.

HETE-2’s operations led to an obvious question: Could the satellite use its optical cameras to study exoplanets? The spacecraft’s photometry proved to be insufficient for the task of identifying transits, found by the kind of dips in a star’s light that the Kepler mission would use to such success. But transit hunting stayed on Ricker’s mind, and by 2006 his team had proposed HETE-S to NASA, pitching it as a Discovery class mission. It would later become a proposal for a Small Explorer Class mission under its current name, Transiting Exoplanet Survey Satellite. A new plan emerged when NASA passed on the first TESS proposal.

What we have now is a spacecraft that will use a ‘lunar-resonant’ orbit, as this MIT news release explains. Growing out of work at NASA GSFC as well as Orbital ATK, the orbit will take TESS on a highly elliptical path between and Earth and the Moon, a stable configuration Villasenor describes this way:

“The moon and the satellite are in a sort of dance,” Villasenor says. “The moon pulls the satellite on one side, and by the time TESS completes one orbit, the moon is on the other side tugging in the opposite direction. The overall effect is the moon’s pull is evened out, and it’s a very stable configuration over many years. Nobody’s done this before, and I suspect other programs will try to use this orbit later on.”

The planned trajectory takes the spacecraft on a swing toward the Moon (with apogee near the Moon’s distance) and then a swing back toward the Earth, a stable orbit one benefit of which is that TESS will not need to perform regular thruster burns to maintain its orbit. With Kepler ending its original exoplanet survey, NASA approved the revamped TESS in 2013 as an Explorer class mission. Kepler’s success was obviously a huge motivator, demonstrating the ubiquity of planets around stars and highlighting the good science that could be done on a mission with a wider view that could scan the nearest stars.

Because many of the nearby stars of high interest are red dwarfs, TESS is built around ‘deep depletion’ CCDs that can detect light in a wide range of wavelengths into the near infrared. Once launched, TESS will begin observations in the southern hemisphere and will divide the sky into thirteen ‘stripes,’ with each of these being monitored for 27 days before the cameras are turned to the next. This method should allow almost the entire southern hemisphere sky to be monitored in the first year, after which TESS will turn its attention to the northern hemisphere.

As to data collection, here’s what NASA says:

TESS has two data collection modes: “postage stamp” images that capture light from individual stars and full-frame images that cover the entire field of view. During an observation sector, 15,000 stars selected from a carefully curated list of 200,000 stars make up the primary targets for exoplanet detection, and TESS will record their brightness every two minutes. Images covering the entire 24-by-96-degree field of view will be acquired at 30-minute intervals. Exoplanets will be found using both data products.

Image: From the transit data alone, scientists will be able to determine the size of the planets and orbital parameters. Ground-based follow-up observations of these objects, possible because of the brightness of the host stars, will allow the determination of the planetary masses. Combining the two, radius and mass, will allow astronomers to determine the density of planets, and hence their bulk composition (are they gas giants? water worlds? big rocks, like Earth?). In addition, transit observations can be used to study the dynamics of planetary systems, such as planet-planet interactions and mutual inclinations. Additional follow-up observations, largely from space with HST and JWST, will allow direct measurement of the atmospheric composition and structure of some planets. This will open the door for a host of new discoveries about exoplanets, and perhaps of the processes behind the formation and evolution of planetary systems. Credit: NASA GSFC.

Once in space, TESS will undergo a 60-day commissioning phase involving instrument calibration and calculations of the spacecraft’s trajectory and performance. After that, data collection commences as TESS produces what the science team will need to generate the necessary light curves. MIT’s Sara Seager and the TESS science team will go to work on the light curves, with mass as a key determinant. The TESS stars are close and bright enough to allow mass determination via ground-based radial velocity methods. As Seager says:

“Mass is a defining planetary characteristic. If you just know that a planet is twice the size of Earth, it could be a lot of things: a rocky world with a thin atmosphere, or what we call a “mini-Neptune” — a rocky world with a giant gas envelope, where it would be a huge greenhouse blanket, and there would be no life on the surface. So mass and size together give us an average planet density, which tells us a huge amount about what the planet is.”

If all goes as planned, TESS should discover, among its thousands of exoplanets, hundreds that are less than twice the size of the Earth. The primary goal here is to identify small worlds where follow-up observations can be made with current or planned telescopes. The James Webb Space Telescope will then have the opportunity to use the TESS target list for deeper investigation, and there will also be useful synergies with the European Space Agency’s CHaracterising ExOPlanets Satellite (CHEOPS), scheduled for launch next year.

But first we have to get the mission off. All eyes on Florida for tomorrow’s attempt.

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Go TESS

“I always get the shakes before a drop,” wrote Robert Heinlein, the words being those of protagonist Johnny Rico in his novel Starship Troopers. I thought of them again this morning because while I don’t tend to get the ‘shakes,’ I do tend to get nervous before a major launch, and that’s what we have today. The image below comes from the TESS mission Twitter account @NASA_TESS (https://twitter.com/NASA_TESS) in a shot just posted as I write. Launch is scheduled for 1832 Eastern time (2332 UTC) and can be seen here.

The launch vehicle is a SpaceX Falcon 9, lifting off from Cape Canaveral. Here’s a bit of NASA’s latest statement:

TESS is NASA’s next step in the search for planets outside of our solar system, known as exoplanets, including those that could support life. The mission is expected to catalog thousands of planet candidates and vastly increase the current number of known exoplanets. TESS will find the most promising exoplanets orbiting relatively nearby stars, giving future researchers a rich set of new targets for more comprehensive follow-up studies, including the potential to assess their capacity to harbor life.

All true, of course, but we should dwell on the fact that while the Transiting Exoplanet Survey Satellite will use the same transit method for exoplanet detection that Kepler used to such effect, the differences are instructive. Kepler looked at a fixed field of view from which to extract a statistical sample of the exoplanet population, one we could use to understand how common various kinds of worlds are in the galaxy. TESS now takes a look at bright, relatively nearby stars, using its four 16.4-megapixel imaging units to survey 85 percent of the visible sky.

I like what TESS project scientist Stephen Rinehart (NASA GSFC — GSFC manages the mission) has to say:

“TESS is opening a door for a whole new kind of study. We’re going to be able study individual planets and start talking about the differences between planets. The targets TESS finds are going to be fantastic subjects for research for decades to come. It’s the beginning of a new era of exoplanet research.”

That’s not hyperbole. By concentrating on stars less than 300 light years away, 30 to 100 times brighter than the Kepler target stars, researchers will be able to study planetary atmospheres using spectroscopy to learn things about mass, density and chemistry that go beyond what Kepler could tell us. Moreover, the TESS Guest Investigator Program will allow the scientific community around the world to take advantage of data outside the core TESS mission.

Can we expect the unexpected from TESS? I think so. Each new step in exoplanet discovery has shown us how much we have to learn. Now we’re looking at targets that may eventually allow us to search for biosignatures, where the findings are sure to be controversial. Just beginning that phase of exoplanet investigation is cause for celebration. Go TESS!

Image: Illustration of the Transiting Exoplanet Survey Satellite (TESS) in front of a lava planet orbiting its host star. TESS will identify thousands of potential new planets for further study and observation. Credit: NASA/GSFC.

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The polis of Artemis on the Moon

Can Andy Weir’s Artemis, the setting for his new novel of the same name, be best described as a city or a town? Or is it better to think of it, as Ioannis Kokkinidis does in the essay that follows, as a ‘polis’? The ancient Greek term carries through the centuries to inform Ioannis’ musings on Weir’s creation, as he examines Artemis, a tourist destination like no other, from a deeply international perspective. Well known for his attempt to keep the science of The Martian accurate, Weir set a high bar, one to which Artemis will invariably be compared. Ioannis Kokkinidis is a resident of Fresno, CA with an abiding interest in deep space. He holds a Master of Science in Agricultural Engineering from the Department of Natural Resources Management and Agricultural Engineering of the Agricultural University of Athens. He went on to obtain a Mastère Spécialisé Systèmes d’informations localisées pour l’aménagement des territoires (SILAT) from AgroParisTech and AgroMontpellier and a PhD in Geospatial and Environmental Analysis from Virginia Tech. Just how realistic, Ioannis asks, is Weir’s polis on the Moon?

by Ioannis Kokkinidis

Introduction

Andy Weir’s new novel, Artemis, is a heist story set on the first lunar town, named Artemis. The book has had a large number of book reviews in the press mostly dealing with its literary qualities. Reviewers though have not quite dealt with the realism of the setting, a town on the Moon named Artemis which lives off tourism, mining and through providing a base camp to space agencies (ESA and ISRO are specifically mentioned) exploring the moon. Over the years many rationales have been given to colonize the Moon. This is the only story I have read – granted I have not been able to read that much science fiction – where tourism is the primary driver of colonization. Andy Weir has said that he first created an economy of the town and then went on to write the novel. His description of a tourist dependent city though has several assumptions that, while mostly true for some American destinations, are quite odd for tourist destinations outside the US. This is an analysis by a person who comes from a country whose economy is highly dependent of tourism, has visited some 30 countries and lived in 5 of them. I am trying to keep this review as spoiler free as possible so as not to ruin the enjoyment of the book to anyone who has not read it, though I hope that those that have not read the book will be able to follow my arguments and form their own opinions. I will also admit freely that I am a biased reviewer; much as I criticize Weir for having an American bias when creating his city, I admit that I have a Greek bias.

Literary Setting

Artemis is the story of Jazz (for Jasmine) Bashara, a young Saudi born woman who has lived most of her life in Artemis and belongs to the first generation to have grown up there. She is the only narrator of the story. We spend the entire novel in her head, and most likely she qualifies as an unreliable narrator in that what she understands is not necessarily what is actually happening. She works as a porter, delivering cargo from the cargo ships to various destinations in Artemis and doing smuggling on the side. One of her clients hires her to do a heist, and following the law of unintended consequences she finds herself forced to do another job with higher stakes to save the city. I will leave the plot description at that, which generally corresponds with the blurb, so as to avoid spoiling it. In the course though of the story she experiences Artemis from a variety of viewpoints, including as a tourist to the Apollo 11 site and describes a functioning town on the Moon as she understands it. Andy Weir has created a variety of characters that, as has been noted, ticks off a large number of diversity boxes, though it also has been noted that the different people he mentions do not quite act as people of their described background do today. On the other hand, considering that the book is set decades into the future on the Moon, we cannot be certain if people will act that way then. Just like The Martian the time the book is set is not given, and while through orbital mechanics you could work out that The Martian was set in the 2030s, the only mention of time is that Star Trek is 100 years old. My sense was that this would place the setting in the 2060s though other sources on the web claim that it is the 2080s.

Andy Weir has an agreement with Daniel Abraham and Ty Franck, the writers behind the pen name James S. A. Corey so that their works are set in the same Universe. The Expanse main series begins 150 years after the short story “Drive” which is about the invention of the Epstein Drive, a revolutionary type of high power high efficiency ion engine by one of the first colonists of Mars. The idea is to form a coherent future history of humanity with a strong basis on science rather than just space opera, from the third expedition to Mars to, well, I am not sure what the end game of The Expanse will be, intergalactic conflict? The Expanse can help fill some of the details in Artemis, the general Wild West type lawlessness of Artemis is what will evolve to the Ceres which, as Detective Miller comments, “has no laws, only cops”. To the best of my knowledge though we have not had published information on what is the actual extent of the collaboration between the three authors so I will be speculating here out of necessity. My critique of the novel should not be understood as dismissal of it. It is after all far easier to tear down than to build, and Weir has done an admirable job in world-building. While Artemis is not as good as the Martian I truly enjoyed Artemis and could not let it down until I finished it.

Tourism in the United States and in Europe

On the two sides of the Atlantic tourism takes very different forms. It is very well known in Europe that Americans only get two weeks of paid vacation per year –the poor for that matter get nothing- as opposed to the European norm of 4 or 5 weeks. The US is more economically polarized than Europe and a far more consumerist: What a European will spend on vacation; an American is more likely to spend on a bigger house, bigger car, bigger appliances etc. The typical American worker will take a day or two off next to a holiday and go with his family to the nearest beach/national park. They will take that one time trip to New York City/Washington DC/Disneyland/Las Vegas, college students will go on Spring Break but generally vacation is not as important as for Europeans. Andy Weir’s lunar vacation is the very American special vacation type: Rather than go to that trip to Las Vegas his vacationers go to Artemis. Since vacation is special anyway, they might as well splurge on it. For a European though some year the vacation may be special, but it is something that will happen every year. European destinations are designed so that you want to come every year, this does not seem to be the case in Artemis.

Another thing that Weir fails to understand is seasonality. Different groups of people come at different times of the year at the same destination, and the destination needs to be flexible enough to leave all satisfied. While in Greece have winter destinations like Arahova and Kaimaktsalan and city break destination like Athens which receive tourists all of the year, some 70% of tourists in Greece arrive between June and September. The tourist season goes as follows in Greece: Two weeks before Orthodox Easter is the High School senior 5 day field trip. 12th graders, accompanied by their teachers but not their parents, visit destinations such as Corfu and Rhodes in theory for educational purposes –they do visit the museums and archaeological sites- and in practice to go clubbing; to drink, sing and dance until the break of dawn or until a student gets smashed and the rest are returned to their hotel while a teacher accompanies him or her to the hospital. Next week is what we call in Greece Catholic Easter –for us Orthodox Christians it is Palm Sunday- and we see European tourists come for their break. Greek tourists join them since the next two weeks are a school holiday due to Orthodox Easter. The two weekends afterwards are the college student party trips to places such as Mykonos and Santorini, similar to American college student Spring Break. By that time it already mid-May foreign childless tourists abound. July and August, when schools are off, are the main tourist months with the peak of the peak being the first 20 days of August. After Dormition (August 15) people start returning home from vacation, school starts in Europe in late August though in Greece on September 10. We still get tourists though until the end of September. Weir’s tourist city somehow it lacks a tourist season, seasonal employees and for that matter tourist destinations beyond the Apollo 11 site.

Physical setting

General Description

Figure 1: A map of Artemis. Credit: Crown Publishing

Artemis, population at the time of the novel being 2,000 is referred as a city. Physically it is located in Tranquility Bay on the Moon some 40 km from the Apollo 11 landing site. I have an issue with the use of the term city: in Greece that a village has a population of less than 2000 inhabitants, a town 2,000-10,000 and a city of over 10,000. For this reason I use in this article the ancient Greek term polis to refer to the settlement. I believe that this term is also more appropriate than city because it also has the connotations of an independent city state rather than just an urban settlement. Artemis has the appropriate size for a small ancient Greek polis: Plato considers that the perfect size for a polis is 5040 citizens, which in his time meant free adult men, and that when it gets to 10,000 citizens it is too big. As Nikias though put it (in Thucydides’ History 7.77.7) “men make the city and not ships and walls empty of people”; which in our case I would amend to “men and women”. We do not know the demographic breakdown of Artemis, how many men versus women, what the age distribution is except that children under 6 were not allowed when Jazz moved and that at the time of the novel the minimum age is 12. Pregnant people are moved to the Earth to give birth. In The Expanse this problem has been solved, but not in Artemis. A lack of children creates very interesting problems, which I discuss later.

Using the analogy of Greece I can attempt to estimate how many tourists visit. As mentioned in 2018 we expect 30 million tourists, 70% of them (21 million) visit the four regions of the Ionian Islands, North Aegean, South Aegean and Crete which per the 2011 census are populated by 1,338,946 people. If we use a similar 15 tourists per inhabitant ratio for Artemis then it should have 30,000 tourists visiting it every year. That would make it a minor tourist destination. Can 30,000 people a year afford to spend something in the order of $100,000 to visit the moon? In view of the studies over who can afford a Virgin Galactic suborbital hop today, I think the answer is yes.

Artemis is described as a playground for rich tourists served by an underclass of workers, one of which is Jazz. Weir has rightly noted that since robots can do everything in space much cheaper than people, tourism becomes the only reason to visit space. Monetary unit of Artemis is the Soft Landed Gram or slug, which is in reality an account with the Kenyan Space Agency that is used to exchange funds on the Moon. Artemis is composed of 5 domes that have different functions: As Weir said during New York Comic Con “Armstrong is industry, Aldrin is the tourist center with casinos and hotels and stuff, Conrad is where the blue-collar folks live, the low-income people. Bean is sort of like suburban life; it’s middle-income folks. And then Shepard is where the really rich people live”.

Those who permanently live in Artemis are retirees who have moved their savings there to avoid taxation, workers in the limited industry that Artemis hosts, service employees for the tourists and Space Agency scientist. In other words Artemis is a cross between the Wild West of the western movies, Monte Carlo and McMurdo Station in Antarctica. These three functions though often clash. For example Monte Carlo is a police state; it has the highest per capita police force per its population in Europe. Somehow though in Artemis a single Mountie, Rudy Dubois, is capable of providing security that the tourists and locals need.

McMurdo station which is the main base of operations for Antarctica has on its own a population of 2,000 people mostly made of supporting crew to the scientists. Will automation in the late 21st century be such that the Moon, which is larger than Antarctica, can have a base of support smaller than that of Antarctica today? We can only guess.

Travelling to Artemis

Andy Weir has written an article where, based on the ratio of the cost of airplane fuel to ticket price for a trip he calculates that the cost of a roundtrip to Artemis will be US$70,000 in 2015 dollars. His premise is that future spaceships will have similar economics to today’s airplanes. If he was to choose passenger ferries as the economic base I am sure he would come with a different number, but I am willing to go along with his price. What I do doubt are his assumptions for the trip specifics. While it is not mentioned explicitly, all would be lunar tourists travel to the Kenya Space Center and blast off to the moon from there. We are not told of any other launching sites sending people to the moon and when one of the characters who is from Hong Kong leaves Artemis, Jazz tells her Kenyan pen pal and accomplice Kevin to track him in a way that assumes that he could only be leaving towards Kenya. The trip from Earth to the Moon and from the Moon to Earth takes 7 days each way. Why do visitors to Artemis need to fly to Kenya first rather than leave from a spaceport closer to their home? For one thing every visitor to Greece does not enter through Eleftherios Venizelos Athens International Airport and then travels to their final destination. Elefterios Venizelos airport is a hub for connections to Greece especially if you are flying a transatlantic flight or your final destination is pretty small but European tourists will often fly directly to Corfu, Mykonos, Rhodes, Heraklion, Santorini or wherever they are going, especially if they are in a low cost or charter flight. Airplanes though are not the only way to visit the Greek island, very often tourists will go by boat. While Corfu has a direct connection to Italy and the islands of the east Aegean direct boats to Turkey, the typical port of origin for a trip to Greek island is my home city Piraeus, the port of Athens. Greece has 107 inhabited islands per the 2011 census, from Piraeus you can get a boat to most. Not all ships travel at the same speed, summer visitors have the option of taking a slow boat, a fast boat or a hydrofoil, in addition to the airplane of that island has an airport with a regularly scheduled flight. Why is Kenya Space Center the only origin to passenger flights to Artemis and why are they slow 7 days trips when Apollo took 3 days other than reasons of novel plot? Shouldn’t there be fast flights to those willing to shell out the money? This is not just an issue of convenience but also of competitiveness as a tourist destination. Studies about Greek tourism get often printed on the Greek press and one of the problems we have is that we are too far away from the countries most of visitors originate compared to our competitors. For a British traveler Crete is twice the air time distance than Ibiza. I cannot guess what travel times will be when Artemis is set, but for a busy CEO who gets very limited time off work, spending two weeks to and from the destination does not seem to be wise. Then again it could be that a trip to Artemis is something like a cruise: It is the cruise ship that is the destination and the passengers just get out for day trips.

We are not told of what engine the crewed spaceships use though the Hermes on The Martian used an ion engine and in The Expanse ion engines are described as the old type used. We are not told how many passengers each ship carries. We are not told if there are specialized cargo ships that make the trip without passenger carrying bulky or heavy loads, or if the passenger ships are the only way to ship stuff. We are not told if the ships have artificial gravity, as the Hermes did, if they have their engine constantly firing to provide gravitation as happens to the ships of The Expanse or if they follow an Hohmann transfer orbit style one firing and coasting in microgravity for most of the trip. All we know is that there is regular service to the Kenya Space Center. My guess is that the ships doing the line between KSC and Artemis have are similar to the Adriatic ferries between Greece and Italy: There are several different accommodation types ranging from deck tickets to luxury suites. Also there are all sorts of amenities on boards such as at least two restaurants, bars and a disco. I also guess is that on the disco they play Nicki Minaj’s Starships, Prodigy’s Out of Space, PPK’s Resurrection and similar relevant space songs.

Foundation of Artemis

The person behind the foundation of the city is Fidelis Ngugi, formerly Kenya’s Minister of Finance. We are told that she managed to create the Kenyan Space Program and later Artemis out of nothing by taking advantage of Kenya’s equatorial position and offering unspecified incentives. Andy Weir never specifically mentions how the whole project started. We are not told who actually financed the construction of the city and of what nationality is the capital that did so. Retirees and criminals provide the capital that expanded and currently sustains the city. Is Kenya the origin of the capital that built the city? On the one hand Kenya has hosted a space program in the Broglio Space Center, located on the San Marco offshore platform. The Italian Space Agency operated the platform and used it to launch the American Scout launch vehicle 9 times between 1967 and 1988. On the other hand as a Piraean when I take a walk at the Marina of Zea in Piraeus I see a lot of megayachts flying the Liberian flag, but rarely if ever the Kenyan flag. Commentary on the web has noted the Spaceresource.lu initiative to mine asteroids, but has not noted that the Grand Duchy of Luxembourg is also offering its own money to start ups as part of the initiative. Will Kenya of a few decades in the future be able to offer significant money, as opposed to just a favorable legal status, in order to be the host country of the lunar city? Also considering the kind of status this sort of project confers to a country, why wouldn’t any of the major powers try and be the host country, especially if they are the ones providing the capital? McMurdo Station is located in Antarctica in the New Zealand claim and has people from all over the world, but from the description I have had from classmates that have worked there, it is at its core an American town.

Another thing we are not told about the city is who the people that founded it were and how they were selected or allowed to live there. Was a tender put out for colonists and who was allowed to answer? We know that Ammar Bashara, Jazz’s father, was not one of the original colonists but moved very early on. The smelter is managed by Loretta Sanchez who invented the -fictional- process used to smelt aluminum and seems to have been there since the start. The city grew with the push pull phenomenon typical of the settlement of the United States: an immigrant would arrive and he or she would bring his relatives – compatriots to live with him, leading to ethnic enclaves. The environmental systems are run by Vietnamese, welders are Saudis, Hungarians control HIBs which are a sort of maintenance robots. When Artemis was founded was there an original person doing that job from that particular country? And how was each job selected, was there an immigration type agreement to hire people of one job only from one country in exchange for that country actually funding the Artemis project? Is there some sort of limitation to immigration to Artemis? For the last parts we are led to believe that this is not the case. Jazz does not know of any agreement forcing all welders to be Saudis for example, is offered other jobs when young and is specifically told that the city welcomes retirees who bring their savings with them without limitations of origin.

The American example of immigration as the choice of the individual is not the only one that exists. The foundation of past poleis has been more of a state affair. Herodotus (4.150-153) mentions how Cyrene in modern day Libya was founded by the people of Thera (also called Santorini) (translated by A.D. Godley):

When Grinnus king of Thera asked the oracle [of Apollo in Delphi] about other matters, the priestess’ answer was that he should found a city in Libya. “Lord, I am too old and heavy to stir; command one of these younger men to do this,” answered Grinnus, pointing to Battus as he spoke. No more was said then. But when they departed, they neglected to obey the oracle, since they did not know where Libya was, and were afraid to send a colony out to an uncertain destination. For seven years after this there was no rain in Thera; all the trees in the island except one withered. The Theraeans inquired at Delphi again, and the priestess mentioned the colony they should send to Libya. So, since there was no remedy for their ills, they sent messengers to Crete to find any Cretan or traveller there who had travelled to Libya. In their travels about the island, these came to the town of Itanus, where they met a murex fisherman named Corobius, who told them that he had once been driven off course by winds to Libya, to an island there called Platea. They hired this man to come with them to Thera; from there, just a few men were sent aboard ship to spy out the land first; guided by Corobius to the aforesaid island Platea, these left him there with provision for some months, and themselves sailed back with all speed to Thera to bring news of the island. But after they had been away for longer than the agreed time, and Corobius had no provisions left, a Samian ship sailing for Egypt, whose captain was Colaeus, was driven off her course to Platea, where the Samians heard the whole story from Corobius and left him provisions for a year […] As for the Theraeans, when they came to Thera after leaving Corobius on the island, they brought word that they had established a settlement on an island off Libya. The Theraeans determined to send out men from their seven regions, taking by lot one of every pair of brothers, and making Battus leader and king of all. Then they manned two fifty-oared ships and sent them to Platea.

Reading Artemis I got the sense that most of those that have made the move are middle class to wealthy people who had a hunger to change scenery. The working class of Artemis seems to belong to the richer 10% of the globe rather than the poor masses of the Third World. The majority though of people who migrate today tend to be poor and often refugees. A $35,000 one way ticket price is not necessarily an obstacle for someone from a poor country to migrate to Artemis. Per the media smuggling into Europe from sub-Saharan Africa, the Middle East or South Asia already costs in the order of $10,000. Per a Washington Post article a North Korean family paid in 2017 $30,000 to smuggle itself to South Korea. It is not at all necessary that the originating country pay for the trip: During the 2015 Aegean immigrant crisis in Greece we got the sense that the Visegrad countries would rather pay to send refugees on the moon than allow then to settle in their own country. Could it be that in several years into the future rich countries will pay to send the poor to colonize space in the same way that they financially support today refugee camps in Third World countries rather than allow refugees to settle in the rich countries? My personal opinion is that if all it takes to settle in Artemis is just paying a ticket to get there, it can easily turn into a dumping ground for the undesirables of the world. There is one major stumbling block for this: The prohibition on children under 6 (originally) and 12 (currently). One of the principal reasons for the postwar depopulation of the Greek islands was the lack of educational facilities. Entire families would move just so their child could go to high school. If children are not allowed, which is also a major limitation to tourism, we are likely to see entire families return to earth as soon as the mother gets pregnant. A city without children, while common in fantasy literature, is not viable in the real world.

Life support

Artemis has a pure Oxygen atmosphere at a pressure that is equivalent to the partial pressure of Oxygen on the earth’s surface. In the real world American spacecraft up to Apollo had a pure oxygen atmosphere, but even Skylab had a mixture of 75% Oxygen 25% Nitrogen due to fears of toxicity from long term exposure to pure oxygen. All other spaceships and the ISS have atmospheric composition and pressure closer to Earth sea level. Ships to Artemis that come from Earth begin with sea level atmosphere and slowly change it over the trip to pure Oxygen. The aluminum smelter produces huge amounts of Oxygen which is then piped in the polis. CO2 from breathing is separated and piped for agricultural use. On earth aluminum smelting produces CO2 rather than O2. The Sanchez process though uses rods made from Carbon and Chlorine that somehow produce O2. The pure oxygen atmosphere, other than serving an important plot point, is a design choice by Weir. I strongly feel though that he has not thought through all the implications. For one thing how do the trees in Aldrin Park that Jazz visits survive under pure oxygen in low atmospheric pressure is a mystery. If all the CO2 in the atmosphere is collected and pumped to the food farms, what could they be possibly photosynthesizing? Also plants get mixed signals at low atmospheric pressure leading them to show water stress even when fully watered. Finally without nitrogen, how would the nitrogen fixing bacteria in the soil fix N2 into nitrates? It could be that nitrogen for the plants is artificially provided through fertigation. Still though, a pure oxygen atmosphere is not very conductive to healthy soil functions.

Another question that is never addressed is what happens to other types of waste. Per Weir water is composed from local Oxygen and Hydrogen that was transported from earth and is continuously recycled. This implies tertiary treatment of wastewater. We are not told where the wastewater treatment plant is. What do they do with biosolids, a.k.a. activated sludge? Do they recover the nutrients? Do they compost it and use it as soil amendment? Do they just dry it and dump it out of the airlock? For that matter what do they do with solid waste in general? In The Expanse there is a universal recycling system, even used instead of burial for the dead. Who collects the garbage in Artemis? Who cleans the street and, more importantly how often do they go on strike? If anything tourists do not like to visit places that are dirty.

Artemis as a tourist destination

Artemis hotel capacity guesses

Weir has said, and it is noted in the novel, that the population of Artemis is 2,000 people. He does not mention though how many people visit the polis as tourists. I will use Greek analogies to try and give an estimate. In a place whose economy is dependent on tourism there are three types of inhabitants: the permanent population, those having temporary accommodation such as a second home who live part of the year –a category that can also include seasonal workers- and tourists which in general far outnumber the local population.

There are several forms of accommodation for tourists. In Greece formal tourist accommodations fall in three categories: hotels, rooms-to-rent (ενοικιαζόμενα δωμάτια) and campgrounds. I am pretty sure that everyone is familiar with hotels. They are generally categorized into star categories depending on the services they offer. Even a 1 star hotel though must meet a minimum number of requirements. Rooms-to-rent is an accommodation type that is described in tourist guides to Greece as “like a bed and breakfast without the breakfast part”. They are often owned by a local and are a family run business. Generally they are required to be licensed by Greek National Tourist Organization (GNTO), like hotels though they have much looser standards than hotels. They are quite popular with Greek tourists because they are cheaper than hotels but they often offer fewer services. Their rooms are often optimized for family vacations. A typical studio has one big room with two queen beds, a kitchenette and refrigerator plus a separate bathroom. They might not even have a reception and it is very rare that they offer breakfast. Very often bookings are not available on the internet, though you can often find the owner/manager’s phone number and call them at any time to book a room in advance. One of the rather typical scenes of summer in a Greek island is rent-a-room owners waiting right behind the catapult of an arriving ferry boat yelling the name of their room and their price in (tourist) English and whatever other language they can speak, trying to get clients among those that did not book accommodation before arriving on the island. In general this is the hardest part of hotel type accommodation to track, the Hellenic Statistical Authority has trouble tracking them because there are several that belong to the informal part of the economy. In other countries there are similar types of non-hotel permanent accommodations such as youth hostels, which are rare in Greece.

Camping in Greece can be in organized campgrounds or outside them, a practice known in Greece as free camping. In general free camping is forbidden in Greece, especially right now with the ongoing refugee crisis. There are several organized campgrounds, private and public, authorized by GNTO and tracked by the Hellenic Statistical Authority. In the last decade the sharing economy has also appeared in Greece with lodgings appearing in AirBnB and similar websites. The Greek government’s first reaction has been to crack down on the practice because of unfair competition to authorized and taxpaying hotels, rooms to rent and campgrounds. The problem that arose that often those putting their vacation home on the internet are people who are foreign citizens that are not permanent residents of Greece. Thus the government has been working with the websites to ensure that this kind of practice is legalized provided the owners of the accommodation pay the kind of heavy tax burden that formal accommodations have. Unfortunately it is difficult to find how many beds are available through the sharing economy, and even less so to find data on how many people have a summer house in a tourist destination that might bring over a friend for a visit.

Greece has 107 islands which mostly live off tourism. Several of them are of similar population to Artemis. On table 1 is a list of islands that had a winter population between 1,500 and 2,500 inhabitants in the 2011 census along with the accommodations they have. Now note that none of these four islands has an airport, though they have heliports mostly for medical evacuations. Visiting them from abroad means for Paxi landing in Ioannis Kapodistrias Corfu International Airport, going to the harbor and taking a ferry boat. For the other three islands which are in the Aegean it means landing at Eleftherios Venizelos, getting to the port of Piraeus and taking a boat trip lasting several hours. For hotels and campgrounds I used the Hellenic Statistical Authority to find capacity. For rooms to rent I used a variety of online sources, most important being the magazine “Diakopes” which has an online website (diakopes.gr) that mentions the capacity of rooms to rent. While there are several sources giving names and phone numbers of rooms-to-rent, only Diakopes had number of beds.

Figure 2: The 4 islands of table 1. From Google Maps

Of these 4 islands the only one I have visited is Paxi in late August 2009, which is in the Ionian Sea, where I stayed in a lighthouse. On top of the tourists staying in hotels, rooms to rent, campgrounds and sharing rooms with friends or strangers on the sharing economy, there were also several yachts both docked on the ports and marinas but also anchored offshore. It is very hard to guess how many people were there visiting, but my guess would be that they were more than the winter population. When complaining about the shortage of medical facilities the local governments gave some numbers to the press: Amorgos claims that while their winter population is 1,800 people, their summer population reaches 10,000. Kea claimed one year to have 5,000 people at the peak and another 10,000. Now islanders are known to exaggerate in order to get more resources from the national government. Table 1 shows that Paxi is rather less developed than other three islands in the Aegean that have a similar population to Artemis. The tourist peak in Greece comes in the first 20 days of August, when it is very hard to find any kind of vacancy, all the bed in Table 1 are definitely slept on by at least one person. If Artemis has the kind of tourist density of Paxi, I would conservatively guess that at the peak it has at least as many tourists as permanent residents, thus 2,000 people. If it has the tourist density of Ios, then at the tourist peak it has over 10,000 tourists.

Somehow all the tourists fit in Aldrin, having rooms that are bigger than Jazz’s cramped submarine bunk type room in Conrad. Weir thinks that a place that per his main character lives off tourism can do so while having significantly fewer tourists than residents at the peak of the tourist season. Granted, it is a long and expensive journey to Artemis, and Artemis also lives off the limited industry it has, supporting the scientists and the retirees. Still in Mediterranean tourist depended town such as Portimão in Portugal, Malia in Greece, Kusadasi in Turkey or Agia Napa in Cyprus, which I have all visited, tourist accommodation and services take more urban space than accommodation and services to locals. Also during the off season the tourist districts are ghost towns, everything boarded up in the main thoroughfare and if something is open it is most likely quite empty of visitors. Jazz never mentions the off season, likely because Weir thinks that as a destination it is not very seasonal. The question of hotel ownership, which is tied to the issue of who provided the capital that built Artemis, is never raised.

The Artemis tourist experience

Artemis follows the day night cycle of Kenya, which is simulated through artificial lighting. Weir describes a polis that generally follows a typical 24 hour cycle as is familiar to him: people wake up in the morning, go to work during the day and sleep at night. When Jazz sneaks out in the middle of the night for her job, she finds the place deserted. This is not how places that receive tourists always work: for one thing you will have many tourists suffering from jet lag. When I last visited Greece I would wake up at 1 am at first, it was 11 am in California. At the end of the 7 day trip, assuming the spaceship follows Kenya time, tourists would have adapted to the change. This is not the case though with shorter trips. Another issue is that individuals have their own time preference, and a comment that we make in Greece is that every nationality has its own cycle: Swedes are known to wake up early in the morning and sleep early even when on vacation. On the other hand we Greeks, who are known sing and dance until the break of dawn, sleep in the morning, waking up no earlier than noon. Working hours and arrangements of the tourist zones adapt to the tourists rather than force the tourists to adapt to them. I was utterly shocked when in Agios Nikolaos in Crete where I worked for 6 months in 2008/9 I discovered that the souvlaki grill was selling meat on Good Friday, until I realized that they were catering to the tourists, not to Greeks. Similarly I remember eating yaurtlu kebap in Chania at 4 am after a night out dancing at a local night club with friends while the store was starting to cook tiropita, bougatsa and other breakfast items for the morning crowd. They would start coming around 5 am when the boat from Piraeus was due and Western tourists were expected to wake up. Furthermore the last time I was in Thassos the super market had gained a large selection of vodkas to serve the needs of Eastern European tourists that are frequenting it. This was not the case during my childhood when foreign tourists were mostly West Germans that drunk beer.

The tourist experience is a two way street, both the locals and the tourists create the destination. However there is an innate tourist experience which is depended on the availability of the attractions at the destination. When I went to Mykonos as a student on I went there to take part of the Mykonos experience: Waking up briefly in the morning to catch hotel breakfast, sleeping again and then after finally waking up after noontime going to Super Paradise Beach to dance with some 2,000 others, mostly students to the electronic dance music played by the DJ. After 6 or 7 pm we would return to the hotel, have dinner, walk around and eventually end up at a more typical night club -the hottest place at the time was called “Space Dance”- no earlier than 11 pm. Afterwards we would go to Cavo Paradiso which opened at 2 am on weekdays and midnight on Friday and Saturday night, though it was wiser to show up after 4 am to listen to lounge music (and drink) while waiting for the sun to rise. Of course Mykonos has many other things to do: a waterpark where we had fun one afternoon before going to Super Paradise, awesome beaches to swim and do watersports, an archaeological museum which I did visit. More importantly, it is the visitation point for the sacred island of Delos where Apollo and Artemis were born which is completely protected as an archaeological site. The Mykonos Experience is not typical of Greek islands: Paros and Naxos for example are more oriented towards families while Tinos receives pilgrims who visit the Church of the Virgin Mary which holds a miraculous icon purportedly painted by the Evangelist Luke. This does not mean that you cannot do most things on most islands; it’s just that each island has a somewhat different tourist character. What is the typical tourist experience in Artemis? What is it that drives people to take such a long trip to the moon?

Jazz impersonates a tourist at some point, so we get to see at least part of it. She wakes up in the morning at a hotel, takes the train to the Apollo 11 site and goes out on an EVA to enjoy the site from behind a fence. The other thing mentioned is going out on a hamster type ball in the lunar surface and bouncing around and visiting the night life, which in Jazz’s case means silently drinking without music. She does mention though clubs where you can dance; she just doesn’t like that kind of entertainment. The Mykonos experience I mentioned is something that you can only really do for a long weekend. More than that you get tired of the dancing, and just go out to experience the beaches, cultural heritage, physical environment, different settlements on the island and other type of attractions. The Artemis experience mentioned above in the end will also fit a long weekend. Day 1 you go to Apollo 11, day 2 on a hamster ball and Artemis is not exactly described as the sort of place where you can go on bar crawls lasting days. Who would really travel two weeks just to spend 3 days on Artemis? There is always people-watching, when you sit on a coffee shop on a main thoroughfare and watch people going by. I remember when in the last year of my undergrad studies we visited Monte Carlo with the university, classmates of mine engaged in people-watching while I went with others to the Oceanographic Museum. As they told us afterwards they were near the casino and would see expensive sports cars driving there to let their patrons off. Apparently my male classmates ogled the cars while my female classmates were salivating over the expensive designer clothes that the fashion models in the passenger seats were wearing. Why doesn’t Artemis have other attractions, such as guided rover geology tours of the surface around the polis, guided tours of the smelter or the nuclear reactor, some amusement park type destination? If you want people to visit, you need to offer them things to do that will take a longer time to accomplish than the trip getting there.

Visitors to Artemis

Tourists described in the novel are families with older children, a married Arab woman without her husband and retirees. This does not quite capture the gamut of categories that choose to go on tourism. If you visit Greece during the school year you will run into foreign schools on educational trips. Much as a trip to Artemis is far more expensive, I see no reason why schools should not be there. I am pretty sure that students of Swiss boarding school, British Public schools or American Preparatory Academies can afford to take a trip to Artemis. Alternatively busy parents can send their kids with the nanny while they are running their corporation. Much as Artemis is rather expensive and too long a trip for Spring Break, the current price for Semester at Sea ranges between $23,950 and $31,950. I am pretty sure that a Semester at Artemis program would appear. We are likely to see corporate retreats for the upper management at Artemis, though scientific conferences seem unlikely: grants will pay a few thousand for a trip of a professor with a few students but not $100,000 each. No religious site is mentioned in Artemis, so we are not likely to see pilgrims before the first monastery is founded there, if not a few generations later after said monastery has produced important personalities. For that matter The Expanse describes a solar system without monasteries of any kind, which I find very weird. If indeed the world of The Expanse is a continuation of today’s world, I see no reason why this kind of religious expression would disappear considering how common it is around the world.

No sporting events are mentioned in the text and thus it is unlikely we would see mass sport tourism. In general it is hard to have physical sports on the moon due to low gravity: you need real training to send a soccer ball in the goal post as opposed to kicking it off the stadium. What would be likely to see is e-sports, a.k.a. video games so long there is no 3 second lag. There are several channels showing e-sports on basic cable, if the company making them wanted they could sponsor a tournament to the moon to raise publicity. Medical tourism is a very high possibility, a case is even mentioned, but for now Artemis lacks the infrastructure to really support it. In the case mentioned a wealthy Norwegian has moved with his daughter to Artemis because of her condition. This is quite realistic to expect. What Weir though seems to ignore is how generous is the welfare state is outside the United States. National Health Systems of wealthy countries do pay for rehabilitation abroad today. Jazz should not be surprised that there is a Norwegian there for that purpose, but that there isn’t a colony of recovering people taking advantage of lunar gravity with the cost being underwritten by their national health systems. As a general note though, tourists crave safety and strong law and order. People do not visit a place so as to get robbed there. Surprisingly Artemis does not offer that, there is only one Mountie that is supposed to offer security for all the people all the time.

Life in the polis

Law and Order

When people are on vacation, they often do things they would not dare do at home, especially after a few drinks. On top of that policing tourists often creates a moral dilemma: How much of their behavior do you police and following which legal and moral code? Tourists come from another society that often has differing values. Do you want to enforce your own society’s values on them? Do you create a tourist enclave under foreign law and if so, how much do you allow of your own people to partake in the vices of the tourists? What should be the case about behavior which is considered normal or at least tolerable in your society but not in the visitor’s society? Should the tourist enjoy the advantage of both societies without either’s obligation? These are issue on top of the more generic issues between law and society for the local population. We really do not see much of tourists being policed in the novel. What we do see is policing of the locals. I was utterly shocked when I read in the novel that Andy Weir’s version of law and order in Artemis features lynch mobs! Why would you ever want to go to a place where your everyday behavior might lead the locals to lynch you and you have no recourse? Tourists are by far the most fickle people over security, they demand absolute security from all dangers real or perceived; this is not what Artemis is offering. This is even more prominent in places that cater to the rich. Monte Carlo is a police state, this is part of the appeal. Italians can display their expensive cars and expensive clothes and jewelry without fear of being robbed, which is a real danger in Northern Italy.

When you live in a tourist country, things that tourists do will make the news. Over time you learn to recognize patterns in behavior, which may or may not correspond to how they act in their home country. Tourists want to participate even partially in the life of the destination, but also want to be part of their home country to which they will return after all. The most typical tourists request is that they watch a home sporting event taking place when they are outside. I most certainly remember when I last was in Thassos every seaside cafeteria/bar in Limenaria was advertising how they were the best place to see the Champions League qualifying game between Partizan Belgrade and Steaua Bucharest. I have no idea how the game went or its aftermath though my sense is that nothing happened afterwards. The issue arises when a game, especially of the kind that attracts passion, has a questionable call. A celebration by the team that the call was in favor can lead to a knuckle fight between groups of fans. While you can expect the establishment’s security to kick you out, this might just lead to a street brawls between mobs of sport fans. Is one Mountie really capable of breaking up a fight between 100 fans? Should Artemis then make watching sports illegal? It is simply not just an issue of sports.

We have had cases in Greece of a tourist killing another tourist because he made advances on that tourists’ girlfriend in a club. I remember the case of a 200 kg female Scandinavian tourist going from bar to bar, causing damage to the places after her advances to male patrons were rebuked, getting thrown out until eventually she made it to the main road, stopped a car by sitting on it and causing hood damage, and then dragging out the driver and sexually assaulting him. But much as these are all sporadic events, and I am sure that everyone living in a tourist country has such stories to share, there is the systematic event known as closing time. In Greece in general the idea of closing time was legislated in the mid-1990s and abandoned after popular outcry: adults do like to be told when to sleep. Still just because tourists do not all leave at the same time, this does not mean that they do not do stupid things on the way out, just that it does not have a specific time it happens. When leaving the bars at closing time in Blacksburg, Raleigh or Fresno the sober will notice the massive police presence out at the time. Drunk people can assault other people for no reason. Getting drunk reduces sexual inhibitions, and this not just leads to sexual assault but also to sexual activity in full public view. A major Cypriot newspaper had in its front page pictures of tourists at Agia Napa behaving indecently at 4 am. Cypriot police did respond to the public outcry by increasing police presence, but this was only up to a limit: Party places live off people behaving in ways that are unacceptable at home. Bar and hotel owners are known to lobby for light treatment, send them to a room or at most to a prison cell for a night, do not send them in prison for long or outlaw the behavior completely. As mentioned earlier there is a strong possibility that Artemis would be a place that never sleeps. Is Rudy capable on his own of managing mobs of drunkards at Aldrin?

Much as tourists are known to get rowdy and be a danger to themselves and others, they also need protection from the locals. I remember a case of bouncers beating a tourist to a coma and killing him because they thought wrongly that he was a potential thief. Dangers to the tourist do not need to be though so obvious. In the novel a barkeep is creating an adulterated distilled alcoholic drink which he tests on a willing Jazz. This sort of behavior is extremely dangerous; in Greece we have had people go blind after drinking adulterated drinks that had excessive methanol. It has not only been tourists: a soldier on the Evros border was visited by his family which crossed into Turkey and bought a bottle of Yeni Raki which they gifted to him. He went permanently blind from drinking it. There are also several other activities that tourist police does in order to preserve the quality of the tourist experience and name of the destination. If a taxi driver, hotelier or restaurant owner overcharges you, the tourist police is where you find recourse. If the restaurant serves you rotten food, there should be police force for that. If the owner of the establishment is not giving you receipts, cooks the books and cheats on his taxes, he should not be allowed to compete with legitimate businessmen. Rudy is shown having great knowledge of criminal activity in Artemis all the way down to domestic abuse, but is he also the kind of person that performs analysis on food and drink, criminal fraud investigations, has knowledge of taxation and economic laws enough to smell a scam? If so, I guess then that after Artemis he ought to apply for the Avengers or the Justice League, he definitely has the qualifications.

But tourists are not the only people on Artemis, there are locals. As mentioned, locals come from many cultures, each with each own values. Artemis though does not have any written laws. If you do something wrong Rudy will beat you, if it is something very wrong you get deported to Earth. Rudy though is not the only source of law, ad hoc morality polices form from among the Artemisians and lynch whoever did something that is against their code of justice. The major problem is, what really informs said code of justice? We are given an example in the novel of someone being lynched for living with teenagers. What if said person was the owner of the largest employer in Artemis? Would people lynch him, or would they protect him and feed his sexual urges with unsuspecting teenagers in order to protect their jobs?

The problem is what happens when we talk about less important things that are offensive to one group but not another. I remember when I was in Portugal in Praia da Rocha near Portimão in Portugal a group of preteen non-Portuguese tourists, each with a beer bottle at hand, walking on the main thoroughfare at the seaside. In Portugal, and in Greece for that matter, this is legal behavior; there is no minimum alcohol age and walking in public with an alcohol container is fully legal. Me and my Portuguese friend were commenting that this is disgraceful behavior but in the end those kids were only imitating their parents, who would also be going on a bar crawl soon. In the US this sort of behavior is considered criminal, both for the kids and their parents (child endangerment). Should American-Artemisians form a morality patrol that trashes stores selling alcohol to minors and lynches store owners, kids and their parents that tolerate this sort of behavior? What happens if the relatives of those so attacked go and attack the lynching mob and their relatives? In Aeschylus’ Oresteia, the only theater trilogy that has survived from antiquity, we have Agamemnon returning from 10 years leading the Greeks in the Trojan War where he is killed while taking a bath by his wife Clytemnestra for cheating on her in Troy, with the help of her lover. Then their son Orestes kills his mother in vengeance for his father’s death, but is then haunted by the Erinyes or Furies, spirits of matriarchical vengeance. Mad from the tormenting of the Erinyes he flees to Athens, where the Areopagus, the court of law for issues of murder, tries him and finds him the killing justified with the goddess Athena casting the tie breaking vote. The theme of Oresteia is moving from a primitive society of the holy law of vengeance to a human political society of laws and courts. Alas Artemis is a primitive society in anarchy, not a socially developed political society. But then again the political system of Artemis is even more problematic that lynching.

Institutional structure

Artemis, with a population of 2,000 people, is approximately the size of a small ancient Greek city state. After reading the novel though it is obvious that politically Artemis is absolute monarchy ruled by the administrator and founder, Fidelis Ngugi. Rudy DuBois enforces the law, which at times he makes up, but he defers to Ngugi, not the people of Artemis. In her person she holds legislative, executive and judiciary power. King Battus as the founder of Cyrene never had the kind of power Fidelis has.

Ancient Greek city states had for the most part a tripartite power structure: at the top there was a king or some other type of titular leader, in the middle there was an assembly of selected men, the modern equivalent would be Parliament and at the bottom there was the General Assembly of all male citizens, the ecclesia of the people. The specific power vested at each level of the governing structure and the composition of each body, let alone the name, depended on the specific city and the time. Macedonia was a monarchy ruled by the king. Below him were the Royal Friends (Vasiliki Eteri) who, in addition to forming the cavalry in battle, advised the king and below them were the Foot Friends (Pezeteroi) who formed the infantry but were also the body that selected who would be king among the male members of the Royal House, would remove a bad king and appoint regents if the king was a minor. In Athens, which was a democracy, the head of the state was the Archon whose main job was to preside over the religious ceremonies of the state. Below him was the Parliament (Voule) which would prepare laws but all the power was at the hands of the ecclesia, the assembly of all free Athenian males which would vote laws, declare wars, sign peace, appropriate money and generally do all acts of power. A citizen who would not take part in politics was called an idiotevon, which is where the word idiot comes from: someone so dumb he is not even interested in politics.

It seems that the polis of Artemis-on-the-Moon is inhabited by idiots living in an absolute monarchy for not only do we not hear of any political body, we do not even hear of any political process. There is no city council or assembly of the citizens. We do not hear of any political discussion for that matter in the entire novel. Worse of all the whole plot of the novel confirms the aphorism about dictatorship that I heard in Barcelona when referring to Franco’s regime: In a dictatorship everyone is oppressed, but if you have the right connections you can do whatever you wish. Jazz is a pawn in a plot of a powerful person to append the current economic structure of the polis. When you do not have an institutional structure in place, violence becomes the only recourse. Much as Weir has tried to build a techno-utopia, scratch under the surface and you see a dystopia where the law of the jungle rules. There is a not so benevolent leader on top who has decisions over life and death among the inhabitants. Those on her good graces can do whatever they please. The rest must suffer lynchings if what their actions do not please some constituency and can suffer arbitrary loss of property, if not life without any hope for recourse.

The issue with the lack of laws and courts not just a theoretical concern. In order to survive and grow Artemis needs external investment. Playgrounds for the rich such as Monte Carlo, Gstaad, Paris and London are also places where the wealthy park their wealth in various forms such as real estate or various financial instruments. Large investors demand a stable institutional framework that spells out what is allowed and forbidden, what are the potential economic benefits and costs and what is the recourse that can be taken if there is a dispute among parties. Say that the property of an absentee landowner is squatted by an Artemisian. What is the course of action he would partake? Ask Fidelis or Rudy directly? What if both prove derelict in their duties because the squatter is strongly connected? Should the landowner hire a mob to evict the squatter? What about the case that we are talking about the landowner demanding higher rent than is in the rental contract and then hiring a mob to expel the tenant? Laws are out to protect everyone from the arbitrariness of others. The irony is that we do see state employees in action: Artemis has a policeman, the inspector that Jazz bribes as part of her smuggling, those controlling the environmental systems and those picking up the garbage. What rules and regulations determines their conduct is never quite told and at times we are led to believe that they just do what they want.

Services

Artemis is somehow both a generally tax free zone and not a financial center. Monte Carlo is a major financial center; wealthy individuals use it in order to hide their assets from their home tax authorities and a safe refuge from political upheaval. The only country that has free access to Monte Carlo’s asset information is France. This comes from an agreement between Prince Rainier and Charles De Gaulle after the French president complained how the Principality is used as a tax haven by rich French. The agreement is that the French are allowed to see French assets but in exchange Value Added Tax of Montegascin industry collected in France is passed on to the principality. Some two thirds of the Principality’s state income comes from VAT in France. In the 1950s, before the agreement with France, Aristotelis Onassis tried to take over the Principality and reduce Prince Rainier to a figurehead. He saw that having sovereign cover to his business would allow him to do things that he could not simply do by only having a corporation. Still Onassis kept the base of his businesses there. Monte Carlo hosts an entire ecosystem of financial services supported by lawyers, financial analysts and other similar jobs. It has though a series of laws to ensure that the wealthy actually reside in the Principality. Corporations cannot take advantage of its tax status unless 3/4th of their turnover comes from within the Principality. Why Artemis does not cultivate this kind of services, considering that having access to cheap capital for financing would allow development of the colony, is unknown, or more in universe a major failure by Fidelis Ngugi.

Agriculture and Food

Per Weir himself the only food grown in Artemis is the green algae Chlorella. It is grown in vats under artificial illumination and then processed through the addition of artificial flavors into gank, the food of Artemis. All other food is transported from Earth and it is quite expensive since at the conversion rate of the slug being 6 slugs per US dollar, each thing transported costs $166/kg. Weir is far from the only person to claim that in the name of efficiency the only crop grown and eaten in space will be algae; that idea seems to be quite popular online. As an agronomist I really do not understand why a concept from the 1940s which from the 1960’s on it had become obvious that did not pan out has such a following among the futuristically inclined. For one thing it was not a topic discussed at the Tri-Societies meetings (Agronomy Society of America, Soil Science Society of America, Crop Science Society of America) when I attended them as a PhD student, as a promising future food source. Searching around the web growing algae for food is more in the purview of the Phycological Society of America. I went to their website to find a snapshot of their current research so I looked up their 2016 Annual Meeting program, which is the most recent on the web. The majority of the sessions and talks were about the biology of algae and seaweed in general, their use as indicators of environmental health though there was once session about algae use as biofuel. I went to Google Scholar and searched “Chlorella production methods”. Of the first 10 papers returned 7 had the word biodiesel in the title, of the other three one was a general review paper on production methods, the second had the word biodiesel in the abstract and the third is a patent to produce a high value ketocarotenoid. Simply put Chlorella production as a food source is not a major research priority today. I realize though that people do not get their information through a search in the scientific literature, as the sections above and below show neither do I when I try to understand a topic on which I am not a specialist. So I looked up the Wikipedia page. It seems that Chlorella specifically, and algae in general, were identified as a promising technology to fight world hunger in the 1940 because it can be grown supplementary to field crops on local ponds and because they can capture 8% of solar radiation in photosynthesis. As Wikipedia though continues in the Chlorella article:

Although the production of Chlorella looked promising and involved creative technology, it has not to date been cultivated on the scale some had predicted. It has not been sold on the scale of Spirulina, soybean products, or whole grains. Costs have remained high, and Chlorella has for the most part been sold as a health food, for cosmetics, or as animal feed. After a decade of experimentation, studies showed that following exposure to sunlight, Chlorella captured just 2.5% of the solar energy, not much better than conventional crops. Chlorella, too, was found by scientists in the 1960s to be impossible for humans and other animals to digest in its natural state due to the tough cell walls encapsulating the nutrients, which presented further problems for its use in American food production.

Eating Chlorella and single cell protein has several disadvantages, beyond the unpalatability. Per Wikipedia eating 50 g/day of single cell protein, and algae qualifies as such, is toxic to monogastric animals such as humans. The reason given is that it contains too much nucleic acid for animals to digest well. Since Wikipedia is not always the best resource I tried to source the statement to something more academic. Turns out review articles on the use of Chlorella mention toxicity due to metal contamination, but do not mention anything about excessive nucleic acid. Thus I looked up to see articles on Chlorella and algae in general as animal feed. Simply put there haven’t been that many recent papers but what I did find was that it is possible to have animal fed up to 10% algae without animal mortality rising. The specific effects depend on the animal species and dose, with some having positive outcomes from substitution and others negative. There haven’t been that many experiments since the discouraging experiments of the 1960s to 1980s because algae derived foods cost 10 times as much as normal animal feed. I could not find experiments on humans to see what a full algae diet would mean, if anything the recommendations online on eating Chlorella are in the order of 2 or 3 g per day with even enthusiasts eating about 15 g/day. The average person eats 1,878 grams of food per day which ranges from 1,012 kg for Somalis to 2,729 for Americans (https://www.nationalgeographic.com/what-the-world-eats/). Is it safe to eat that much Chlorella per day, every day for your entire life? Is Chlorella capable of providing all the nutrients humans need to survive? Per the internet six types of nutrients are necessary for human survival: proteins, carbohydrates, lipids (fats), vitamins, minerals and water, with fiber mentioned as a seventh component in other sites. This categorization is pretty consistent with the nutrition requirements for animals that I am familiar with as an agronomist. Is Chlorella alone, even with additives and artificial flavors, capable of providing the right nutrients of the right biological value (think saturated versus unsaturated fats or why olive oil is superior to butter) at the proper quantities for a proper human nutrition. My feeling from my experiences as an agronomist and from life experiences in general is that it is not.

Efficiency is a very fluid concept and one needs to balance a large series of parameters. Per my college textbooks factors affecting agriculture are categorized into climatic and edaphic (soil based) factor. Climatic factor include solar radiation, temperature, humidity, wind, evapotranspiration and CO2 concentration. Edaphic factor are soil structure such as mechanical properties, soil composition and nutrients. In following Weir’s efficiency fallacy, rather than choose radiation efficiency I choose nitrogen use efficiency. The crop with the highest Nitrogen Use Efficiency is almonds with a value of 70% when the rest of the major crops are closer to 40%. Thus if we are to follow Weir’s logic Artemisians should only eat almonds which they turn to almond milk, almond oil and other almost products. Artemis’ food production facilities should look then like Fresno, after all most of the world’s almond crops are produced in California’s Central Valley.

ESA’s MELiSSA project is, to the best of my knowledge, the most advanced ongoing project to create an artificial ecology that produces sufficient nutrient food for all. I have talked about them before here in Centauri Dreams. They use 9 crops (wheat, tomato, potato, soybean, rice, spinach, onion, lettuce and spirulina) and they have enlisted Michelin starred chefs to make food that is tasty in addition to nutritious. Also their configuration is tied to the life support system, turning human waste to food. A mature MELiSSA system will not need the aluminum smelter pumping oxygen into the system; it will be able to recycle the entire nutrient supply. So far MELiSSA is in development of the regenerative systems to supports its cycle but it has made significant progress into creating palatable balanced food. Their finding, which is also corroborated by other space food research, involves the use of energy bars for space nutrition: put the entirety of a balanced meal in a compact calorie laden bar that takes little volume to store and can be eaten rapidly. This is far less innovative than it seems: the food that hoplites brought while on campaign away from home was pasteli, a bar made of sesame seed and honey. It seems that the food eaten by astronauts exploring Mars will be a descendant of what Alexander’s pezeteroi ate while conquering half the known world.

But what would be the required area to locally feed Artemis using hydroponics? A number I remember from my undergrad days is that hydroponics requires 250 to 500 m2 of growing area to feed a person for a year. Now growing area does not meet geometric area, if you grow three crops of potatoes in an area of 100 m2 then you have a growing area of 300 m2 but a geometric area of 100 m2. This is very important when you consider that crops grown hydroponically have a faster growth cycle than soil grown crops. Assuming 250 m2 per person, to feed 2,000 people you would need 500,000 m2. Per Figure 1 the domes have a diameter of 200 m, or a radius of 100 m meaning that their area is π*1002 = 31,416 m2. Dividing the two values we need the surface area of 15.9 domes. However the dome does not have only one level, after all Aldrin Park alone takes 4 levels. Conrad bubble has Up 19 and Down 6, thus at least 25 levels.

Another common fallacy that Andy Weir falls into is related to artificial flavors. He seems to believe that they can be sourced on the Moon. Artificial flavors are not, for the most part, mineral flavors. Their many sources are petroleum and coal. These are not known to be found on the moon, thus they would need to be imported from earth. If so, why do they not just import natural flavors and have beef flavored gank made with bouillon?

Speaking of flavor, if Jazz has been eating gank since she was 6, by now she should find it very tasty because of what I call the black broth effect. Spartans ate a staple soup made of boiled pig’ legs, blood, salt and vinegar, known in Greek as μέλας ζωμός. By all accounts it was horrible to taste: a Sybarite upon eating it remarked “Now I know why Spartans do not fear death, to die is to be relieved from eating it”. Yet Spartans ate it with pleasure and often did not like other food. When a Spartan delegation visited the Lidyan king Croesus and asked what they wanted, they rejected the luxurious Asian foods he offered and wanted black broth. Jazz ought to welcome eating gank after 20 years on it.

In terms of drink what is mentioned is beer and hard liquor. Hard liquor comes from earth but we are led to believe that that beer is local, even though Artemis does not grow barley or for that matter rye and wheat. It is very likely that Weir has in his mind a definition of beer that significantly differs from the Reinheitsgebot that includes the use of Chlorella in brewing, otherwise at $166/kg Jazz should not be able to afford getting drunk. If some sort of beer-like concoction is grown locally, why is yeast not also consumed afterwards as food as is the case with marmite and vagamite? Or is the yeast used in the creation of gank? We are not given an ingredient list for gank after all.

Industry

Artemis is not a major industrial location nor is industry a major employer. Two major heavy industries are mentioned, Sanchez Aluminum and the Nuclear Power Plant. One light industry is specifically mentioned too, Queensland Glass. Other than that the tourist trinket shops sell models of the Apollo Lunar Landers made out of lunar dust that seem to be factory made rather than hand maid. Sanchez Aluminum is the biggest industry employing 80 people. As mentioned earlier they use a fictional process for smelting of Aluminum that also produces oxygen as a byproduct. In actual aluminum industry what they use is carbon rods made from tar and coal. Sanchez Aluminum consumes 80% of the power produced by the nuclear power plant. We are not given specifics on the nuclear power plant, but there is good reason to believe that the nuclear fuel cycle takes place on earth rather than the Moon. Artemis, simply put, is not energy independent. The specifics of the light industry inside Armstrong are not spelled out beyond the glassworks.

Education

We are told of Jazz’s backstory through a series of letters with her Kenyan pen pal Kevin and Jazz apparently has had teachers who told her that she has a lot of potential. We are led to believe that these teachers live in Artemis. All four Greek islands of table 1 have elementary, middle and high school. In these islands though children are allowed to be born, this is not the case with Artemis where children under 6, and eventually under 12 are not allowed. We have seen islands be depopulated by families moving to the nearest city so that their children can go to middle or high school. Realistically the entire family would move from Artemis as soon as the woman got pregnant, not just the mother. Not allowing children is not conductive to the long term development of a place, and the school system is the epicenter of the problem.

Speaking of the school system, who does it work for and what is being taught? Who sets up the school curriculum and who do the teachers answer to? Who decides what is to be taught in say Physics class? Where can the students appeal if they do not like their grades? Who has written the school books and what is their ideological slant? In the US homeschooling is driven by many reasons but for most parents choosing it, it is to avoid the secular wickedness of public schools. In Greece debates over what is in the school history books are known to bring down governments. Is Fidelis the one who in the end decides what is the next generation of Artemisians getting taught? Does she promote democracy as the preferred regime, or is education used to justify her absolutist regime? The educational system of the Byzantine Empire taught students about democracy in the Ancient Greek city states which it considered its direct ancestor (see for example emperor Leo the Wise’s Tactics or George Sphrantzes Chrlonicle) and about the Roman Republic (after all it saw itself as the Roman Empire) but considered the absolute monarchical regime as the best possible. The Byzantine Emperor was the Ideal Perfect King of Plato’s Republic. What are Young Artemisians taught that ought to be their place in the polis and in the Solar System? Are Artemisians taught that they are God’s chosen people in the way that youth of the Byzantine Empire were? Are they taught that Artemis is a unique exceptional state in the mode of American Exceptionalism? Are they taught that the individual is only worth as the cog in the machine of juche and must submit to the will of the Dear Leader to create the perfect socialist regime? We are not told.

We are not even told what is the official language of Artemis, though we are told to believe that it is English. A major omission that I saw is the lack of multilingual education, at the very least in order to cater to the tourists. When Jazz showed up in the hotel impersonating a female Arab tourist who did not speak good English, why did the receptionist did not speak Arabic to her or call someone who did? Having lived in a tourist zone, the first requirement for receptionists is multilingualism. In Agios Nikolaos of Crete I did run into ads requesting night receptionists that spoke French, I seriously considered staying in the city after my agronomist contract ended to work as one since I am fluent in four languages. Who in Artemis would teach Cantonese, Arabic (to mention tourist languages specifically spoken in the novel) or any other language and who would certify the tests? Even if they use state certification from Earth, who would be the one administering the tests on the Moon?

Artemis apparently has no university though it hosts quite a large number of PhDs exploring the moon as members of their space agencies. Monte Carlo has a university more specialized towards business. It is located in Stade Louis II, taking up the space below the bleachers. Since Artemis has the staff, it could host a university that would also attract people from Earth to immigrate there as students. Then again, it would also need an education authorization body and we have not seen any such bodies in the novel.

Health Care

Health care in Artemis is provided by exactly one doctor, Dr. Melanie “Doc” Roussel. She has a small private medical clinic that is capable of limited medical care and hosts a few beds. No nurse is mentioned or any other medical personnel and apparently it lacks intensive care. If you come down with something serious in Artemis and Doc Roussel cannot cure it, you will die unless you can survive long enough for a 7 day trip back to Earth. No other medical practitioner on the surface of the moon is mentioned. Now this is a rather typical case for the rural United States as I have learned from experience but for a European this is unacceptable. ESA has a medical doctor stationed at the Concordia station in Antarctica doing medical research on the isolated researchers there during winter, as part of human factors research for space exploration. Why would ESA, or any space agency for that matter, allow its personnel to be in such a medically limited location as in Artemis? For that matter McMurdo Station, which also has a population of 2,000 people does have a hospital staffed by the National Science Foundation. Per what I could find of the internet it has a staff of 5: 3 doctors, 1 nurse practitioner and one plain nurse. It is not just the scientists that need a hospital, the tourists also need a place to mend alcohol intoxication or broken bones and, more importantly, for retirees. I will leave aside the possibility of medical tourism. In the studies on how make Greece a more attractive destination for European retirees to live there one thing consistently mentioned is that retirees demand a large and well equipped hospital near because being elderly they have significant medical needs.

The Greek islands host medical facilities for the locals and the tourists. While there are private doctors in all of Greece, the Greek public national health system provides services to all of the population of Greece. Our health system is composed of hospitals, health centers and farm clinics and it follows the administrative division of the country. There is a publically owned hospital in the capital of every prefecture in Greece (the American equivalent is the county) and below that there are health centers and farms clinics in the subperfectures and municipalities depending on the population. To use the example of the four islands from table 1, Amorgos health center has a pathologist, a general doctor, a microbiologist and a pediatrician. There are also 4 farm doctors –the Greek state requires medical school graduates to work two years as farm doctors before they are allowed to start medical specialization- plus two ambulance drivers and one lab technician. Ios has 6 doctors of which one is a general practitioner, one is a pathologist, one orthopedic, one pediatrician and two farm doctors. Also it has 3 nurses and one midwife. The locals complain that this is insufficient. Kea has two general doctors, one pediatrician, one nurse, one lab tech and one ambulance doctor. Paxi has one pathologist, one general practitioner, one pediatrician, one dentist, 3 nurses, one medical equipment technician, one physical therapist and one general duties technical secretarial staff. The people complain that they do not have specialized doctors such as cardiologists, psychiatrists, gynecologists or ophthalmologist. They have only one ambulance driver but considering that they get only 1 to 2 incidents a month that require transportation they find it sufficient. Now the Paxians are I would say a bit over complaining. Per article 5 of Greek law 4486/2017 these are the staffing analogies that primary health facilities should have: 1 General Practitioner per 2,000 to 2,500 adults, 1 pediatrician per 1,000 to 1,500 children, 2 radiologists per 25,000 to 30,000 inhabitants, 1 biopathologist per 25,000 to 30,000 inhabitants, 1 cardiologist per 25,000 to 30,000 inhabitants and 1 dentist per 10,000 inhabitants. Since Paxi isn’t that big, for specialists they should be able to find them in Corfu or Igoumenitsa. Alas though Artemis does not have any other medical facilities closer to earth, so it ought to have a small hospital with a staff of around 10 people and an intensive care unit. How though would the people to pay for health care if there is no health insurance on the Moon?

Labor conditions

Going on vacation most often means that you have paid leave on your work contract with your employer. If you are self-employed you can close your business, which is likely to happen at time when business is low anyway. But what are the labor conditions of those working in Artemis, servicing the tourists? In addition to slugs what else is part of each paycheck? Do Artemisians get paid time off themselves? Do they get retirement or health insurance? If they have a complaint with their boss, who is to arbitrate it? I think that it is safe to guess that employees of Earth based space agencies and their contractors have to broad protections and rights their Earth bound colleagues do. Since Artemisian employees are generally unionized we can expect those working for major employers such as Sanchez Aluminum to have some benefits to go with the paycheck. It is obvious though that Jazz has absolutely no benefits in addition to whatever she scrapes by her gig. For that matter, the person that she bribes so that she can do her smuggling also does not seem to have any benefits: if he was certain of his future, why would he need a bribe? Rather the whole premise of Jazz taking The Big Job is that she can retire, most likely because there is no retirement system. Most certainly we do not hear of people discussing just how many stamps or days they needed to get before the system gives them a pension or they qualify for unemployment benefits. Granted, Jazz hangs out at a bar where people drink in silence, rather than the modern day ecclesia: a coffee shop where people constantly talk about politics, gossip, sports and relationships. Still the only time that a union is mentioned is Ammar Bashara saying that it is stupid to pay 10% of his paycheck as union dues, it is just taxation. If members of the welder’s union get health care and pension as part of their contribution, then Ammar is the one being stupid. The labor conditions of Artemis are what the communists in college when I was an undergrad were deriding as the evil medieval future that was coming if we did students did not rise in a worker’s revolution against capitalism. Considering that the people rose against Existent Socialism and brought its end 8 years before I first entered college, I was not keen on revolting. They did have a point though: the Uber-ization of work means that my generation works in worse labor condition than my parents’. Weir believes that this will continue on, until by the time of Artemis workers have no rights and we are back in the era of Karl Marx and the Reserve Army of Labor.

Up until the late 19th century your prosperity in life was associated with the years you were able to be productive. Starting with Bismarck and Napoleon III we have seen in Europe the construction of the welfare state: The idea that everyone deserves a minimum of rights in life, such as a safe and healthy job, health care so that being sick does not mean going bankrupt, income at the end of life when you are too sick and frail to work, financial support when you are between jobs, paid vacation so that you can look forward to when you are doing a monotonous job. Now there is a long discussion over what and how much the welfare state should cover and when does it become a hammock holding back the economic well-being of society. What is certain is that Artemisians do not have any sort of safety net. When I was living in Agios Nikolaos in the winter of 2008/9 I would see every 15 days people lining up at the unemployment office to receive benefits. I was told that they were hotel workers who do not work in the off season while the hotel is closed, the tourist season after all does not last more than 6 months for most of Greece. The relationship is mutually beneficial to the hotel owners and the state: The money that their seasonal employees get in the winter is money that they will not demand in the summer as higher wages. Unemployment status in Greece also gives health insurance under some limitations. What is surprising about Artemis is that an informal welfare state also appears to be nonexistent. As a good grandson I took care of my grandparents at the end of their lives, just as they had taken care of me as a baby. In Artemis children under 6 originally and 12 by the time of the novel are not around. Would young Artemisians feel responsibility to take care of their grandparents if all they really knew of them was the grumpy old person who is telling teenager you what not to do? Also monasteries are known to act historically as retirement communities: The Byzantine historian Sphrantzes at the end of his life wished to retire and discovered that the only way he could get elderly care was as a monk. So he was forced to divorce his wife, which they both loved each other very much and they both took monastic vows in separate monasteries. It is during this time that he wrote his Chronicle, giving an inside view of the Fall of Constantinople since he was a personal friend of the Last Emperor, Constantine XI. Artemis is a place for the rich to go and die, the rest are better off if they do not reach old age.

Final thoughts

During my last bout of unemployment I decided to catch up with the Arrowverse. I started watching Arrow first, and after I had seen all the episodes I wrote a post on Facebook what I saw as wrong. The show, at least in the first seasons, tries to be rather realistic and anchored in the real world. Afterwards I moved up to The Flash. Much as I enjoyed it far more, and I do think that it is the better show, from the moment I was willing to accept superpower granting Dark Matter and the whole concept of the Speed Force I really could not complain about them getting some things wrong. Andy Weir has written a science fiction novel with a very high degree of realism that invites the sort of nitpicking I have engaged in in this article. His World Building does leave gaps but this is understandable, even the master World Builder of our era, George R. R. Martin has left quite a few gaps in A Song of Ice and Fire. I look forward to reading Andy Weir’s next novel and I hope that he addresses some of the questions I raised.

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Breakthrough Discuss Streaming Live

I don’t usually reproduce news releases here, but this one is of unusual interest given that I am both a strong supporter of Breakthrough Starshot and a partisan for getting academic conferences available through live streaming. Breakthrough Discuss begins today and its sessions will be well worth your time, given the array of distinguished speakers and the tight attention to matters interstellar.

The third annual Breakthrough Discuss scientific conference (https://breakthroughinitiatives.org/events/discussconference2018), which will bring together leading astrobiologists, astronomers, engineers, and astrophysicists to advance discussion around recent discoveries of potential life in the universe and novel ideas for space exploration, will be held on Thursday, April 12, and Friday, April 13, and full sessions will be available for live viewing on YouTube.

The two days of discussions will focus on “Alien Life: Diversity in the Universe,” with sessions discussing the search for life in our solar system, possibilities for non-terrain life in the universe, as well as progress in novel space propulsion.

The conference will be live streamed on the Breakthrough Prize’s YouTube page:
https://www.youtube.com/breakthroughprize

Viewers are encouraged to participate virtually via a chat feature, which will be monitored by a facilitator who will feed questions into the panel discussion sessions.

Carolyn Porco, American planetary scientist and leader of the Cassini Imaging Team, and Martin Rees, British cosmologist and astrophysicist, will serve as keynote speakers.

Sessions will be chaired by Penelope Boston, Director of the NASA Astrobiology Institute, Chris McKay, planetary scientist at NASA Ames Research Center, Svetlana Berdyugina, Director of Kiepenheuer Institute for Solar Physics, Lisa Kaltenegger, Associate Professor of Astronomy at Cornell University, Sigrid Close, Associate Professor of Aeronautics and Astronautics at Stanford University, and Zachary Manchester, Assistant Professor of Aeronautics and Astronautics at Stanford University.

WHAT: Watch the third annual Breakthrough Discuss scientific conference, which will bring together leading astronomers, engineers, astrobiologists and astrophysicists to discuss recent discoveries of potential life in the universe and novel ideas for space exploration.

WHEN: Thursday, April 12, and Friday, April 13 — PACIFIC TIME
Schedule: https://breakthroughinitiatives.org/events/discussconference2018

WHERE: Watch Live on YouTube, https://www.youtube.com/breakthroughprize

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Disk Imagery from Nearby Young Stars

Here’s an interesting situation: Around a star designated GSC 07396-00759, a member of a multiple star system, astronomers have found an edge-on disk. Such disks are helpful ways of studying planetary evolution, as we’re looking at gas, dust and planetesimals that represent a planetary system in the process of formation. But at GSC 07396-00759, the disk is more evolved than the gas-rich disk around the T Tauri star in the same system. In other words, we have two stars evidently of the same age whose disks show a different evolutionary pace.

Elena Sissa (INAF-Osservatorio Astronomico di Padova) is lead author of a new paper on this find, in press at Astronomy & Astrophysics. The paper puts the matter this way:

Even if there is no “smoking gun” proof, the system characteristics all together tend to favor an evolved/debris disk nature for GSC 07396-00759 over a primordial/gas-rich disk. If confirmed, this is a very interesting discovery since this star and V4046 Sgr form a coeval physically bound system that would consist of a gas-rich circumbinary disk and a debris disk. Therefore it is of paramount importance to search for gas in the GSC 07396-00759 disk.

Image: This SPHERE observation is the discovery of an edge-on disk around the star GSC 07396-00759, which is a member of a multiple star system included in the DARTTS-S sample. Oddly, this new disk appears to be more evolved than the gas-rich disk around the T Tauri star in the same system, although they are the same age. The disk extends from the lower-left to the upper-right and the central grey region shows where the star was masked out. Credit: ESO/E. Sissa et al.

Such finds highlight the reasons we study disks in the first place, to learn more about how planetary systems emerge. And we’re now getting new images from the SPHERE instrument mounted on the European Southern Observatory’s Very Large Telescope in Chile that show us discs in more detail than ever before. SPHERE stands for Spectro-Polarimetric High-contrast Exoplanet REsearch instrument, a planet finder whose primary job is to do direct imaging of gas giants around nearby stars, but one that’s also fine-tuned for turning up protoplanetary disks.

In the image below, we’re looking at T Tauri stars, which are less than 10 million years old and varying in brightness. Our early Solar System may well have looked something like the disks we see here. A survey called the DARTTS-S (Discs ARound T Tauri Stars with SPHERE) produced most of this work, though the GSC 07396-00759 find came from a different survey effort; both used SPHERE to produce their images. The targets are all relatively near, ranging from 230 to 550 light years from Earth.

Image: New images from the SPHERE instrument on ESO’s Very Large Telescope are revealing the dusty discs surrounding nearby young stars in greater detail than previously achieved. They show a bizarre variety of shapes, sizes and structures, including the likely effects of planets still in the process of forming. Credit: ESO/H. Avenhaus et al./E. Sissa et al./DARTT-S and SHINE collaborations.

The SPHERE imagery also takes in a target previously investigated by the Atacama Large Millimeter/submillimeter Array (ALMA), which found two rings of material within the disk surrounding the Sun-like star IM Lupi. Both rings are made up of heavy ions in the form of DCO+ (deuterium, carbon, oxygen). Here I turn for background to work by Karin Öberg (Harvard-Smithsonian Center for Astrophysics) and colleagues, who studied the IM Lupi disk’s chemistry and published a 2015 paper on the matter. Says Öberg:

“With ALMA we can directly observe this chemistry in discs that are right now in the process of making planets. The molecules have formed two spectacular rings. The inner one we expect to see; the outer one comes as a complete surprise and sheds new light onto the properties of a protoplanetary disc’s outer reaches.”

For more on this unusual disk, see Surprising chemistry seen in molecular rings around young star, an article in Astronomy Now. SPHERE now offers IM Lupi’s unusual disk in striking detail.

Image: This spectacular image from the SPHERE instrument on ESO’s Very Large Telescope shows the dusty disk around the young star IM Lupi in finer detail than ever before. Credit: ESO/H. Avenhaus et al./DARTT-S collaboration.

The images of T Tauri star disks were presented in a paper entitled “Disks Around T Tauri Stars With SPHERE (DARTTS-S) I: SPHERE / IRDIS Polarimetric Imaging of 8 Prominent T Tauri Disks”, by H. Avenhaus et al., to appear in in the Astrophysical Journal (preprint). The discovery of the edge-on disk is reported in a paper entitled “A new disk discovered with VLT/SPHERE around the M star GSC 07396-00759”, by E. Sissa et al., to appear in the journal Astronomy & Astrophysics (preprint).

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Exoplanets: Accelerating the Pace of Discovery

As we await the launch of the Transiting Exoplanet Survey Satellite, I want to pause this morning to remind everyone of another significant mission: CHEOPS (CHaracterising ExOPlanet Satellite). The decade ahead is going to be an exciting one for exoplanet discovery, given that we have TESS about ready to go, JWST in the pipeline despite its problems, and CHEOPS expected to launch in 2019. Eleven European nations are involved in CHEOPS, a European Space Agency ‘S-class’ mission that will study exoplanetary transits.

Image: Artist’s impression of CHEOPS at work. Credit: ESA.

In 2026, we can look forward to ESA’s PLAnetary Transits and Oscillations of stars (PLATO) mission, which will study up to a million stars in search of planetary transits, with the emphasis on rocky planets in the habitable zone. In 2028, we have the ARIEL mission (Atmospheric Remote-sensing Infrared Exoplanet Large-survey) to anticipate (see ARIEL: Focus on Exoplanet Atmospheres). What a run of space-based photometric discovery lies ahead.

We’ve been studying exoplanet transits from space since 2006, when the CoRoT mission launched. CoRoT examined two fields of view, each containing several thousand dwarf stars with magnitudes ranging from 11 to 16. In its five years of operations, the mission discovered, among several dozen exoplanets, a planet designated CoRoT-7b, which turned out to be the first exoplanet identified as having a rocky core.

Kepler expanded the field by measuring brightness variations to an accuracy of order 20 ppm in a single field of view of approximately 100-square degrees, and continues to function in its remarkable K2 extended mission. We’ve been tracking developments in the thousands of Kepler confirmed and candidate exoplanets since the mission began. Now CHEOPS will target bright stars to provide a large sample of small planets with well-measured radii, enough to provide the density information we need as we probe deeper into planet formation and evolution. Both missions will feed prime exoplanet targets to our anticipated JWST.

CHEOPS will use an optical telescope with an aperture of 30 cm inserted into a Sun-synchronous orbit about 800 kilometers above the Earth, with a mission duration of 3.5 years. Synergies between CHEOPS and TESS should be apparent, with CHEOPS delivering precise radius information on targets identified by the earlier mission. The photometric precision CHEOPS achieves should be similar to Kepler’s, while observing brighter stars located anywhere on the sky and targeting small exoplanets already found by radial velocity methods as well as transiting Neptune-class worlds that have been detected by ground surveys.

This morning comes news that construction of CHEOPS has been completed, with engineers from the Center for Space and Habitability (CSH) at the University of Bern packaging the instrument for delivery to Madrid, where it will be integrated to the satellite platform. Airbus Defense and Space in Spain built the satellite platform and will supervise testing of the integrated spacecraft in coming weeks. At the conclusion of various further rounds of testing, the spacecraft will be sent to Kourou in French Guiana, from which it will be launched in 2019 by a Soyuz rocket.

Image: The CHEOPS telescope in the cleanroom of the University of Bern. Credit: Thomas Beck / Universität Bern.

As the first mission designed to follow-up previous planetary discoveries around bright stars, a primary goal is to pick out those exoplanets most suitable for further investigation, particularly those whose atmospheres may be suitable for analysis. Planners hope that CHEOPS will be able to provide radii of unprecedented accuracy in those cases where ground measurements have provided a value for the planet’s mass, allowing the calculation of planetary density. Beyond choosing targets for further spectroscopic analysis, the telescope will also be used to examine Neptune-class planets and study the atmospheres of ‘hot Jupiters.’

With TESS taking the baton from Kepler, CHEOPS to follow, then PLATO and ARIEL, we are looking at all but continual dedicated exoplanet missions into the 2030s, perhaps 30 years from CoRoT through PLATO, as my friend Ashley Baldwin has reminded me in a recent email. Bear in mind that this time period will also see the emergence of the extremely large telescope (ELT) class of instrument on the ground. A golden age of discovery goes into accelerated mode.

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A Triton Lander Mission

What would be our next step in the exploration of the outer system once New Horizons has visited one or more Kuiper Belt objects (KBOs)? One intriguing target with a nearby ice giant to recommend it is Triton, Neptune’s unusual moon, which was imaged up close only once, by Voyager 2 in 1989. The views were spectacular but at the time of the encounter, most of Triton’s northern hemisphere remained unseen because it was in darkness. Only one hemisphere showed up clearly as the spacecraft passed the moon at a distance of 40,000 kilometers.

Our next visit should tell us much more, but we’re still working out the concept. Thus Steven Oleson’s Phase II grant from NASA’s Innovative Advanced Concepts (NIAC) office. Oleson (NASA GRC) calls the idea Triton Hopper. In his Phase I study, he identified the various risks of the mission, analyzing its performance and its ability to collect propellant. For Triton Hopper — moving from point to point — would rely on a radioisotope engine that would collect nitrogen ice and use it for propellant, mining the moon’s surface to keep the mission viable.

Image: Graphic depiction of Triton Hopper: Exploring Neptune’s Captured Kuiper Belt Object. Credit: S. Oleson.

Triton is interesting on a number of levels, one of which has received recent examination As with other outer system moons, we’re learning that there may be a liquid ocean beneath the crust. Let me quote a short presentation from Terry Hurford (NASA GSFC) on this:

There is compelling evidence that Triton should be considered an ocean world. Fractures observed on Triton’s surface are consistent in location and orientation with tidal stresses produced by the decay of Triton’s orbit as it migrates toward Neptune. Tidal stresses can only reach levels to fracture the surface if a subsurface ocean exists; a solid interior will result in smaller tidal stress and likely no tectonic activity. Tidal stresses therefore provide a mechanism for fracturing and volcanism analogous to activity observed on Enceladus and, possibly, Europa. Given that Triton’s interior has dissipated a tremendous amount of energy as heat, which likely drove differentiation, and that this heat may remain until the present day, an energy source likely exists to drive geologically recent activity. Moreover, it is possible that tidal volcanism has facilitated, if not dictated, the expression of this activity on Triton’s surface.

Triton’s surface seems to be in geological motion, given how few craters show up in the Voyager views. We can also factor in that this is the only large moon in the Solar System with a retrograde orbit, leading to the view that it is a captured dwarf planet from the Kuiper Belt. That nitrogen that Steven Oleson wants to use should be abundant at the surface, with a mostly water-ice crust to be found below. Also of considerable interest: Triton’s surface deposits of tholins, organic compounds that may be precursor chemicals to the origin of life.

Image: Triton’s south polar terrain photographed by the Voyager 2 spacecraft. About 50 dark plumes mark what may be ice volcanoes. This version has been rotated 90 degrees counterclockwise and artificially colorized based on another Voyager 2 image. Credit: NASA/JPL.

Geologically active places like Triton are intriguing — think of Io and Europa, Enceladus and Titan — and we can add Triton’s nitrogen gas geysers into the mix, along with its tenuous nitrogen atmosphere. No question a lander here would offer abundant science return. Oleson proposes heating that surface nitrogen ice under pressure and using it as a propellant that would allow a continuing series of ‘hops’ as high as 1 kilometer and 5 kilometers downrange. Thus we would get images and videos while aloft, and surface analysis while on the ground.

Intriguing. The thin atmosphere and even the geysers could be sampled by a Triton Hopper in the same way we have looked at the Enceladus plumes, by passing directly through them.

Working with GRC colleague Geoffrey Landis, Oleson presented Triton Hopper last year at the Planetary Science Vision 2050 Workshop in Washington DC. The thinking is to land near the south pole in 2040, in the area where geysers have already been detected. The surface can then be explored in as many as 60 hops, covering some 300 kilometers. Using in situ ices as propellants offers a uniquely renewable potential for mobility.

Oleson’s Phase II work will cover, in addition to mission options to reach Triton and descend to the surface in about 15 years, details of safe landing and takeoff of the hopper. Propellant gathering is obviously a major issue, one that will be explored through a bevameter experiment on frozen nitrogen (a bevameter can measure the properties of a surface in terms of interaction with wheeled or tracked vehicles). Also in play: How to collect and heat the nitrogen propellant and find ways to increase hop distance, solutions that could play into other icy moon missions.

Be aware, too, of a Phase II grant to Michael VanWoerkom (ExoTerra Resource), who will be studying in situ resource utilization (ISRU) and miniaturization. VanWoerkom’s NIMPH project (Nano Icy Moons Propellant Harvester) will deepen his investigation into mission refueling at destination, producing return propellant on site. The work thus complements Triton Hopper and deepens our catalog of strategies for sample return from a variety of surfaces.

The NASA precis for Oleson’s Phase II study is here. The NIMPH precis is here. The Hurford presentation is available as Hurford et al., “Triton’s Fractures as Evidence for a Subsurface Ocean,” Lunar and Planetary Science XLVIII (2017) (full text), but see as well Should we reconsider our view on Neptune’s largest moon?, which ran at Astronomy.com.

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