Interstellar Visioneers

What does it take to conceive a new vision of the future and drive the idea forward? Keith Cooper, editor of Astronomy Now as well as Principium, the journal of the Institute for Interstellar Studies, examines the question in the context of a new book. Grand ideas aren’t enough, for the commitment to build community and expand the audience for a breakthrough are the necessary foundation. What Gerard O’Neill and Eric Drexler can teach us about this and how their example may inform the future choices of the interstellar movement are at the heart of Keith’s review. Along the way come many questions, especially this: Is a ‘failure of nerve to play the long game’ what is holding us back as we contemplate a future among the stars?

by Keith Cooper


In 1972, a think-tank of businessmen, politicians, economists, scientists and bureaucrats going by the name ‘The Club of Rome’ (they held their first meeting in the Italian capital in 1968) painted a picture of a dystopian future where by the year 2030 rising population, increased urbanisation and industrialisation, coupled with depleted resources would all mean one thing: that the planet was nearing its limits and the only way to survive would be in strict moderation, an unchanging equilibrium of austerity (a buzzword today) and restrictions. It was a depiction of a nightmare future where progress effectively shudders to a halt, yet their report, ‘The Limits to Growth’, has been read by 12 million people.

By painting this picture of a narrow, limited future, The Club of Rome inevitably spurred a reaction from the scientific cognoscenti who knew no bounds, were not defined by limits, looked to technology to create a better future and as part of their visions aimed quite literally for the sky. To folk like Princeton physics professor Gerard O’Neill, ‘The Limits to Growth’ was something to rally against and drive the proliferation of his ideas for orbiting space colonies. Humankind, O’Neill reasoned, need not know boundaries or limits if it went into space where room and resources aplenty exist. Throughout the 1970s he galvanised the public to his ideas, inspired the grassroots to form advocacy groups such as the L5 Society to keep beating the drum on space colonies, and became a media darling thanks to his vision of the future, appearing on celebrity talk shows and magazine covers.

For science historian Professor W. Patrick McCray of the University of California, Santa Barbara, author of a new book called The Visioneers: How A Group of Scientists Pursued Space Colonies, Nanotechnologies and a Limitless Future, O’Neill was an archetypal visionary with the technical know-how to present a realistic case. For McCray, having not only an idea about the future but also having the smarts to make that technological vision a reality are the essential ingredients for a ‘visioneer’, the inspirational visionary mixed with the rigorous, comprehensive work of an engineer. However, writes McCray in his book, a visioneer must do more than produce ideas and calculations; a visioneer also forms and shapes a community of supporters to promote their ideas and is both protector and promoter of the vision and the community that builds up around it.

Optimistic visions of the future

McCray’s two chief visioneers are O’Neill and K. Eric Drexler, who as a student was a member of the 1970s pro-space movement with O’Neill before going on to popularise his vision for nanotechnology in 1986 with his best-selling book Engines of Creation. Both men had ideas way ahead of their time. To O’Neill, humankind had three choices: stagnation (the choice offered by The Club of Rome), annihilation (the threat of the Cold War was serious) or expansion into space and the settlement of orbiting colonies, built from miles and miles of rotating metal cylinders. In hindsight it seems crazily optimistic but back in the 1970s it inspired the public’s imagination in a way no human spaceflight project has done since Apollo. Similarly, Drexler’s revolutionary vision of nano-scale machines reassembling matter at the atomic level, or rushing through our bloodstream to dismantle cancerous cells, is still far from being realised.

visioneers 1

Given that we can’t yet go on holiday to a space settlement, or treat illnesses with a shot of medical nanobots, it is tempting to describe O’Neill and Drexler as visioneering failures. McCray sees things a little differently. O’Neill’s space colonies may not exist yet outside science fiction, but the community he built, signified by the L5 Society, helped spawn today’s pro-space movement in the hands of private initiatives such as Elon Musk’s SpaceX or Peter Diamandis’ Planetary Resources. Where O’Neill failed, one of these large corporations may succeed. The role of large business and billionaires is not exactly the route O’Neill envisioned, but it shows that there is more than one route to the future. Regardless, the power of a visioneer is in creating a community, inspiring people to take up the mantle further down the road if necessary. In a way it is kind of like a built-in insurance policy; ensuring ideas are passed onto the next generation so that others are sufficiently inspired to pick up the pieces should the initial visioneer fail, learn the lessons and have another go at it.

“I think the two key roles visioneers serve are to encourage the formation of communities of like-minded people to support or oppose their ideas, but also ultimately I think visioneers are best at promoting debate and discussion about what we – society – want the technological future to be like, what we hope and fear,” McCray tells me. “I see this happening more today in debates about geo-engineering, synthetic biology, drones, autonomous cars etc.”

There’s another subject to add to McCray’s list of contemporary topics: interstellar flight, an area that McCray recognises is an arena for potential visioneers. In fact it doesn’t take a huge leap to see the parallels between O’Neill’s ‘High Frontier’ and the interstellar movement and hence the possibility that we could learn something by the study of O’Neill, Drexler and other visioneers.

Courage to play the long game

In a way ‘The Limits to Growth’ provided an adversary, an alternative philosophy for the visioneers and their movements to rise up against. More specifically, it was seen by the visioneers as an attempt to reign in the great potential of human technology and progress. While today we don’t talk about ‘The Limits to Growth’ report as much – it is 41 years old after all, although The Club of Rome and its philosophies still exist – it feels like it has been reborn in different guises just as O’Neill’s pro-space movement has been reborn in the hands of SpaceX and Virgin Galactic. Today other fears replace the oil crises of the 1970s: the economic crash, a growing unease of how sophisticated technology is integrating itself into society, the battle to save the environment in the face of increasing climate change and the frictions the environmental debate causes, and the usual bouts of war, terrorism and international sabre-rattling. Limits were the enemy in the 1970s; today it is despondency leading to shortsightedness and a failure of nerve to play the long game, essential for a long term project such as interstellar flight.

An interstellar community already exists, as evidenced by the success of the Centauri Dreams website, the plethora of interstellar organisations and the now frequent symposia that draw hundreds of attendees to discuss the topic. It’s not quite as organised as the L5 Society, but it isn’t required to be; today the Internet and social media provide the glue that bind the community together; in the 1970s it was mailing lists, newsletters and local chapters in university physics and engineering departments.

However, once the community is in place and growing, and the ideas of the visioneer are being disseminated, those ideas become owned by the many members of the community. McCray describes in his book how O’Neill started to distance himself from his own community when people he deemed as undesirable joined, most notably LSD guru Timothy Leary who had strong ties with high-ranking members of the L5 Society and co-opted O’Neill’s space colonies for use in his own philosophy. Furthermore, O’Neill was angered by the producers of Sean Connery’s 1981 science fiction film Outland, set on a space colony reminiscent of O’Neill’s; Connery’s character was also called O’Neill.

Meanwhile, Drexler also faced a battle to hold onto his ideas for nanotechnology, a battle he ultimately lost. Despite often being cited by other scientists as their gateway into nanotechnology thanks to Engines of Creation, Drexler found himself sidelined by fellow academics who doubted the the engineering of nano-bots. Today nanotechnology bears no resemblance to his advanced technology, but rather is mostly just another avenue of mainstream chemistry.

“I think that the ways in which their ideas were co-opted was perhaps something they didn’t think about but was probably inevitable,” says McCray. “I also think that once you put your ideas out there and work to get attention for them, then you have to accept the fact that others will distort them, replicate them, modify them etc. O’Neill seemed to take this more in his stride than Drexler but then, with nanotech, I think there was more at stake, i.e. real funding.”

Should the interstellar community worry about losing ownership of our ideas? Next year director Christopher Nolan will release a new science fiction movie called Interstellar, rumoured to involve Kip Thorne’s wormhole physics just as Carl Sagan’s Contact did. Will our community bristle at Hollywood co-opting the word ‘interstellar’? Will we grimace at the likely bad presentation of physics and starflight? Probably, but the horse bolted a long time ago; spaceflight is a staple of science fiction. while there have also been many scientific proponents of interstellar flight over the years, from Les Shepherd to Robert Forward. Nobody owns the vision of interstellar flight; what is needed now is visioneers to make it happen. We should embrace its prominent exposure in science fiction rather than try and protect it from mainstream dissection by movie reviewers and audiences, and use that as a spur to present a more scientific take through the media.

However, what if someone were to come in and take over the whole shebang, bypassing the community entirely? A billionaire entrepreneur, one of the nouveau-rich that are trying their hand at commercial spaceflight, could easily do that. Visioneers within the community that have worked hard to refine their concepts and present them in an agreeable fashion could suddenly be kicked aside, yet in the process their role could become even more important.

As O’Neill’s vision fell apart, others today are now looking at potentially picking up where he left off. The analogy I like to make is that Hari Seldon seeded his secret Second Foundation as insurance should the first Foundation fail, which it did thanks to the unpredictable arrival of The Mule. The many organisations that populate the community today are vital because they help prolong the vision should others – including multi-billionaires – fail. It is essential that interstellar visioneers keep that grassroots support bubbling along, even in the lean times. As Icarus Interstellar‘s Andreas Tziolas said in the comments to a recent Centauri Dreams article on interstellar organisations, the community exists because “we’re sick and tired of waiting for someone else to do it!”

Yet visioneers also need patience. “O’Neill and Drexler imagined futures that they themselves would be able to partake in,” says McCray. “I see visioneers operating in this middle group, not two to three years out, but also not 200-300 years over the horizon.” Interstellar flight is a long-term goal and it remains an open question whether any of us will still be around if and when it happens. Perhaps interstellar requires a different breed of visioneer?

Capture the moment

Ultimately, the type of visioneer says something about the times they live in. Part of that is what the visioneer is rallying against. But in the 1970s, moving into the 1980s, the arena was different from what it is today, when society seemed far more open to the possibilities of the pro-space movement, popular culture embraced all kinds of spacey things such as Star Wars, Star Trek, the futuristic sounds of Jean Michel Jarre and prog-rock concept albums and the mass market science fiction paperback and magazines such as Omni, which McCray credits as being a powerful influence on the proliferation of visioneers’ ideas. Would a book like O’Neill’s The High Frontier ever become a bestseller today? Would members of the interstellar community find themselves on the cover of Time Magazine like O’Neill did in the 1970s? Instead interstellar visioneers have to work out how best to use whatever is unique about these modern times to spread the message, rather than trying to recapture glorious past times – social media is an obvious avenue. Having 100,000 followers on Twitter is surely as good as being on the cover of a magazine with 100,000 readers?

Most importantly, visioneers have to be able to build things. Craig Venter, for example, created a biological cell with a synthetic genome in his quest to create artificial biological life. O’Neill and students at MIT – including Eric Drexler – constructed laboratory prototypes of electromagnetic catapults called ‘mass drivers’ that O’Neill envisioned as vital for launching raw materials from the Moon or asteroids into Earth orbit where they could be used for construction of space habitats. Demonstrating the ability to build technology to aid a visioneer’s idea is a key part of gaining credibility. On a grander scale it might be an efficient fusion reactor or the development of human hibernation; on a smaller scale it could just involve inventing a new magnetic nozzle that aids the generation of powerful magnetic fields in a tokamak, demonstrating microwave beaming in the laboratory or creating spacecraft concepts and blueprints like Daedalus and Icarus.

The Visioneers is one of those rare books that is equally about science and personalities, a book that explores the history of visioneers but by doing so also asks questions for visioneers of the future to ponder. For anyone interested in building a better future, in pushing the envelope of technology, in developing a scientific vision, or in creating tomorrow, The Visioneers is an essential read as McCray weaves a fascinating narrative that can easily be applied to the interstellar vision. And as the biographer of the visioneer movement, what advice does McCray have for visioneers in the interstellar community?

“It would be not to limit oneself to just talking,” he says. “Build things. Develop designs. Create a community. Show people what’s possible, if only to start a discussion about what we want the future to be like down the road.”

It will likely not take a single visioneer, but many, whether working together or in rivalry, or separated by decades, but each with their part to play. Maybe some that will succeed are already here, reading this. Perhaps no one in the current community will succeed and it will fall to a new group. Or possibly it will be someone who has not even been born yet but will be inspired by the work of the community today, to whom we are entrusting the future, because good ideas never die.


On Memory and Destinations

There was a time when people collected old photographs in drawers and photo albums, a time before the digital age when you wasted three or four shots getting just the one you wanted, and the perishability of film was born home every time you saw colors fading on an old image. Yesterday I browsed through black and white snapshots of family members long gone, pictures taken in the 1920s and 1930s, and thought about how we try to preserve memory by framing a moment. Then I thought about how July 19, 2013 was itself going to be preserved, a celestial alignment snatched from time as seen from deep in the Solar System.

Carolyn Porco, who serves as imaging team leader for the Cassini Saturn orbiter, calls July 19 ‘a day for all the world to celebrate.’ Cassini will look back at our planet and snap our picture in natural color next to the fabulous system of rings and moons it’s been showing us all along. Thus a pixel from Cassini’s 1.44 billion kilometers will become an opportunity for reflection, for unlike the ‘Pale Blue Dot’ image taken by Voyager 1 back in 1990, this snapshot, actually a mosaic, has been announced in advance. I had hoped to write about it yesterday but got caught up in non-space related work and managed no post at all. But looking forward or back, the image is still worth celebrating.

Porco was part of the ‘Pale Blue Dot’ team that was so memorably treated in Carl Sagan’s book of the same name, so her thoughts have weight. Of the new effort, she says this:

“My sincere wish is that people the world over stop what they’re doing at the time the Earth picture is taken to revel in the sheer wonder of simply being alive on a pale blue dot of a planet, and to appreciate the ever-widening perspective of ourselves and our world that we have gained from our interplanetary explorations. We are dreamers, thinkers, and explorers, inhabiting one achingly beautiful planet, yearning for the sublime, and capable of the magnificent. Let’s celebrate that, and make this one day a day the whole Earth smiles in unison.”

Indeed. Narrow and wide-angle images of the Earth will be taken from 2127 to 2142 UTC (1727 and 1742 Eastern time in the US) on the 19th. Around that time yesterday, as I thought out this post, I was having a gin and tonic after a day that had proven stressful both mentally and physically. I sat out on the deck with a fine, gentle breeze rustling the trees and thought about framing moments in time, and how in one particular moment our home world — all of it — will be captured by an exquisite technology.

North America and part of the Atlantic Ocean will be illuminated when Cassini records its mosaic of the Earth as Saturn is backlit by the Sun. A 2006 Cassini image had also shown the Earth from Saturn space but this new imagery will be the first taken in natural color, as human eyes would see it, and represents the first time images of Earth and Moon have been taken with Cassini’s highest resolution camera. We should wind up with something like this:


Image: A simulated view from NASA’s Cassini spacecraft on July 19, 2013, showing the expected positions of Saturn and Earth around the time Cassini is taking Earth’s picture. Credit: NASA/JPL.

The old photos in the chest in my living room are all filled with memories, people walking at the edge of a great river in western Illinois, the building where my dad built his coffee company in St. Louis, the snapshots he and my mother took on a cruise to South America. I can see relatives I only dimly remember still young, standing by Buicks and Packards, getting ready to go to war.

Our space-based images point to both past and future. Looking back at our planet frames us as a species awash in immensity, but one beginning to leave its world and reconfigure its perspective. We note the grand accomplishment of the images we take but are inevitably reminded how close Saturn is to the Earth in terms of interstellar distances. Then we compare the past images of our pale blue dot to the pixels of places we have yet to visit. Thus the haunting view of Alpha Centauri that Cassini made some five years back. Below, Centauri A and B are clearly visible over the horizon of Saturn, though the red dwarf Proxima Centauri is too faint to be distinguished.


Saturn is 30,000 times closer than the Alpha Centauri stars. We have evidence of but one planet there and even that has yet to be confirmed, so we are much in the dark. Cassini’s new picture of Earth will show us our own world from a distance that renders its features as unknowable as whatever planetary systems may exist 4.3 light years away. The Cassini images of these two places are not about discovery but about reflection. They should spur our philosophy as much as our curiosity. We bring meaning to our quest for knowledge when we look both forward and back, remembering what has been and who we are, while anticipating what we are to become.


Exoplanet Targets in Nearby Space

I’m a coffee fanatic. Not only do I drink a lot of the stuff, but I roast my own beans and love fiddling with roasting times and fan speeds, trying to hit exactly the right note. And with a just-brewed carafe of Burundi by my side this morning, it’s natural enough that I would be drawn to an exoplanet tool called ESPRESSO. Echelle SPectrograph or Rocky Exoplanet and Stable Spectroscopic Observations is the next generation spectrograph for the European Southern Observatory’s Very Large Telescope, which has already played such a huge role in finding distant worlds.

Using the HARPS spectrograph, the VLT already holds the record for most exoplanet discoveries from equipment on the ground. Upgraded with ESPRESSO, the VLT should be primed for even more fine-tuned radial velocity measurements. HARPS was designed to get us down to about the 1 m/s level, although its effective precision is considerably tighter. But we’re still not in range of Earth-like planets in the habitable zone. The Earth creates a radial velocity variation of 9 cm/s on the Sun, about three times smaller than HARPS can work with. ESPRESSO makes up the difference, taking us down to a few cm/s if all goes well, making detection of habitable planets in Earth-like orbits feasible from the ground.

Installation at the VLT is currently scheduled for 2016. As we ponder near-term developments like this, it’s intriguing how much is happening to push our knowledge of smaller exoplanets forward right here on Earth. The Next-Generation Transit Survey (NGTS), like ESPRESSO, follows a highly successful predecessor, in this case the Super-WASP project that went after exoplanets on the cheap. That’s ‘cheap’ as in camera lenses bought on eBay that have found 65 exoplanets.

Although Super-WASP (Wide Angle Search for Planets) demonstrated how successful searches could be managed from the ground, the Kepler ‘long stare’ into the Lyra/Cygnus star field examined planets whose transits are in many cases at the limit (or beyond it) of ground-based follow-up observations. NGTS goes after ‘hot Neptunes’ and ‘super-Earths’ from its site at Cerro Paranal at the European Southern Observatory in Chile, looking for transits around bright, nearby stars. These are transits that would allow follow-up observations by radial velocity methods, revealing not only the radius but also the mass and density of these worlds.


Image: Artist’s impression of the completed NGTS, a robotic facility to be sited at ESO-Paranal. Credit: Next-Generation Transit Survey.

Quoted in this feature in Astrobiology Magazine, Warwick University’s Peter Wheatley, co-principal investigator for NGTS, says the idea is to gather “… the first statistical sample of measured densities for small planets.” He adds: “We believe this sample will allow quantitative tests of planet formation, migration and evolutionary models, and will drive the development of future models.” But with space-based equipment like Hubble and the James Webb Space Telescope in the mix, we can also look toward identifying useful targets, smaller planets bright enough for their atmospheres to be studied through ‘transmission spectroscopy,’ where starlight that is absorbed as it passes through the atmosphere is analyzed to flag its components.

From the NGTS site:

The observation of the planet during its transit at many different wavelengths allows us to obtain its transmission spectrum (stellar light passing through the planet atmosphere). The transmission spectrum is measured by identifying the small differences in transit depth as a function of wavelength. This technique usually requires extremely high signal to noise data and has been successfully applied only on a few planets orbiting bright stars, like for example HD189733. However it is a powerful technique measuring the distinct signature of chemical components in the atmosphere of a planet. This technique can be used to search for water on some planets, and even eventually for biomarkers on rocky planets. It has been successfully carried out on GJ1214b, a Neptune type planet, using FORS [FOcal Reducer and low dispersion Spectrograph] observations. However, the discovery of additional bright targets is essential for this technique to be more widely applied to planets in the Neptune size range.

And here’s the GJ1214b work, showing how the transit light curve can be used to tease out atmospheric information:


Image: Transmission spectrum of GJ1214b measured by FORS (Bean et al. 2010). Credit: Next-Generation Transit Survey.

The Next-Generation Transit Survey is to be a robotic installation using an array of small telescopes operating in the 600-900 nm band, maximizing their sensitivity to K and early M-class host stars. Finding the brightest exoplanets in the ‘hot Neptune’ and ‘super-Earth’ categories will give us fodder for study by the VLT as well as Hubble and JWST, with all key technologies already demonstrated through a successful prototype. Also aided by NGST data will be the European Space Agency’s CHEOPS (CHaracterising ExOPlanets Satellite), slated for 2017 launch, which will target already identified planets to improve their transit measurements.

Ground- and space-based instruments are intertwined as we push exoplanet studies toward smaller and smaller planets. We already confirm many transits through radial velocity methods with tools like HARPS, but to take the study of exoplanet atmospheres to the next level will require even larger observatories like the planned European Extremely Large Telescope, or the proposed Colossus. In an era of big equipment, it’s heartening to think that relatively inexpensive tools like the NGTS can play so vital a role in finding the targets for these behemoths.


Starship Century, Part Two

Adam Crowl concludes his discussion of the recent Starship Century conference in San Diego. Videos from the session are now becoming available online.

by Adam Crowl

Lunch at the Starship Century Symposium was provided by UCSD, allowing attendees to remain nearby, adding to the discussion and trading of ideas and concerns. Certainly I appreciated the chance to catch up with friends and faces from the other side of the Pacific, as well as meeting new people. Having read people’s novels, books or scientific papers for years, then meeting them on Facebook or email, I felt like I knew some of them already. Meeting authors that I had grown up with like Larry Niven, Joe Haldeman or David Brin was something I was getting used to, as I was more eager to discuss their interstellar ideas than succumb to fan-shock. I finally had my ideas about Larry Niven’s fusion-shield, from his “Known Space” stories, confirmed by the source, but didn’t quite get to talk to David Brin about the Fermi Paradox during the whole event.


The afternoon of the first day was thematically about “New Space” – what we’re doing, as a species, in the near term of a commercial nature. Of course, this was largely from the North American perspective. Patti Grace Smith [video], one of the senior Regulators of “New Space” in Washington DC, spoke about her role in helping commercial space efforts by creating a more operator friendly legal environment. Patti also gave a summary of the key-players in commercial sub-orbital and orbital commercial space efforts, the most prominent being SpaceX, while the most secretive has been Blue Origin, whom Patti has encouraged to be more open.

Image: Patti Grace Smith speaks on commercial space.

Beyond Chemical Propulsion

Once we’re in orbit the only way is Out – into the wider Solar System. Chemical propulsion isn’t up to the task, so Geoffrey Landis [video] made the argument that Nuclear Thermal Rockets (NTRs) will be the “Workhorse of the Solar System”. Geoff’s presentation was based on material presented previously, to more technical audiences, and the technical reports he referenced are also widely available. So he focussed initially on the long history of the NTR in astronautics – dating back to the late 1940s and almost brought to operational readiness by NASA’s nuclear rocket program, before being shelved in the early 1970s. Since then research has focussed on newer materials and newer testing techniques of reactor designs, largely via computer simulation and hot hydrogen gas experiments to simulate the operating environment of engine components. An important point is that NTRs allow transport of humans and their machines in reasonable time-frames all the way to Jupiter. Inside the orbit of Jupiter there exist many sources of the chief NTR propellant – hydrogen – usually in solid form attached to oxygen as water. Conveniently water has many other uses for human beings, thus will be in demand.


Image: Ian Crawford (left) and Geoffrey Landis.

That key point lead neatly into the next presenter’s talk. Chris Lewicki [video] of Planetary Resources gave an intriguing overview of the next steps for one of the first “asteroid mining” companies. Chris had clearly covered the material many times before, showing a polish that only comes with practice. The inner Solar System has abundant energy from the Sun, and convenient chunks of material orbiting in free space in the form of asteroids (and dead comets), but the first task is prospecting and finding the most convenient resources to retrieve from their distant orbits. Thus the Planetary Resources plan of building small satellites with autonomous control, to minimise ground-control costs, and many of them, to achieve savings via mass-production. Interplanetary prospectors that are cheap enough to crash into an asteroid if that’s what the mission requires. Eventually the quest for precious high-value materials in space to return to Earth will also have the side-benefit of producing great volumes of useful in-space materials, such as water. In time the inner Solar System could have a viable network of resource trading, with precious metals being dropped back to Earth via “whiffle-balls” of foamed metal, and storage depots of liquid hydrogen for Landis-style NTRs carrying people to the Moon, Mars and the asteroids.

Panel: The Future of New Space [video]

With those thoughts in mind the day ended with a special presentation and viewing of a small fraction of Arthur C Clarke’s paintings and memorabilia, now at the Geisel Library. Seeing promotional material from 2001: A Space Odyssey“, signed by the actors, and similar items made me mindful of the vast legacy that Clarke’s work had inspired. In the nearly 50 years since he began working with Stanley Kubrick on 2001, we have achieved but a tiny part of what the 1960s imagined possible, a reminder of the difficulty of making dreams real.

Among the Starship Designers

Intense conversations ate up the hours after the scheduled activities, shadowed by my awareness that I was to be the first speaker on Day Two. My sleep was a broken few hours, an hour at a time, looking at the clock, while my subconscious was working on arranging what I would say. Needless to say, I have no idea how the delivery looked, as I covered slide-after-slide of starship concepts – most of which are covered in the anthology [video]. One gratifying aspect was being able to point out several starship designers in the audience – Freeman Dyson nodded approvingly when I discussed his interstellar Orion from 1968, and I discussed Al Jackson’s role in the development of the laser-powered ramjet. As a parting note I mentioned the “Ultimate Starship” – my personal suggestion, based on the late Robert Forward’s idea of a neutrino-rocket, to use electroweak unification physics to convert ram-scooped mass directly into a neutrino-jet. One day I will need to write the paper.

Jim Benford [video] covered the concept of microwave sail-ships, giving a fascinating look into his experimental work in the late 1990s with carbon-sails in vacuum chambers, being made to do amazing things via concentrated beams of microwaves. Jim, like his brother Greg, is a physicist, an alumnus of UCSD, but an applied physicist who has literally written the book on high-power microwave systems, such as the million-watt RADAR regularly used by the world’s armed forces. Thus he is well able to discuss the practicalities of propelling sails to interstellar speeds via beams of microwaves and has written several papers covering the economics of micro-wave starships. An elementary conclusion of the Benfords’ experiment is that a conical sail can very effectively ride a polarised microwave beam and be spun so it is self-stabilising. A less encouraging finding is that the cost of energy will dominate interstellar missions at high-speeds. Before we can reach the stars we will need to create abundant energy supplies.


Image: James Benford (left), Larry Niven and Gregory Benford at the book signing.

Next up was John Cramer [video], a physicist from the University of Washington, well-known to SF fans via his “Alternate View” columns in Analog, as well as several novels. John focussed on the use of wormholes to allow rapid transit to other star systems. Wormholes are simply connections between two points in space-time, compatible with Einstein’s equations of General Relativity as one possible mathematical solution. Outside the wormhole itself, observers would see two “ends” of the one space-time structure. Whether they exist or not is a matter for astronomical observation, as larger wormholes should produce distinctive gravitational lensing patterns that astronomers might be lucky enough to see.

If the connection formed between the two ends of a wormhole is shorter than the distance through regular space-time, then passing through the wormhole allows apparently faster-than-light travel, though nothing ever exceeds lightspeed locally. Thanks to time-dilation – the slowing of time experienced when approaching lightspeed – a time-lag can be developed between the two ends if one end is sent to a distant star. For example, if one end is accelerated to a time-dilation of 7,000 (0.99999999c), then only 75 minutes is required for the travelling end to appear to travel 1 light-year from the stationary end’s point-of-view. John Cramer discussed how this might allow a network of rapid-transit wormholes to be set-up throughout the Galaxy – with the caveat that the network can’t be allowed to form a “Closed Time-like Circuit” else this might destroy the wormholes via amplifying quantum fields.

On Target Stars and Life

Before lunch British astronomer Ian Crawford [video], a fellow member of Project Icarus, discussed what we might find amongst the nearer stars, out to 15 light-years. A planetary system probably exists around every star, something we can say with statistical confidence thanks to the work of the “Kepler” exoplanet detection mission, but discerning every planetary system will require improvements on current techniques. And we almost certainly haven’t found every small star within 15 light-years yet, as the 2013 discovery of a brown-dwarf binary at just 6.5 light-years should remind us. Ian made the forceful point that even with vast telescopes able to image those many new planets and stars, there’s only so much we can learn via telescopes. If we find a planet showing all the signs of life, we will only know more by actually going there – via robotic proxy, in Ian’s opinion.

Once we do go, will we survive? This was the after-lunch opener from Paul Davies [video], who posed the puzzling question of how terrestrial life might interact with truly alien life in another star-system. Could they co-exist, with no biochemical compatibility at all? Could they share common simple biochemicals, but foreign genetic and protein chemistry? Or could the two integrate in ways we haven’t yet imagined? Even more intriguingly, Davies suggested that we might already co-exist with “alien” biochemistries on Earth – organisms might exist in niches that otherwise exclude our kind of biology. A suggested location might be at temperatures higher than what known microbes can tolerate, or in highly alkaline fluids, such as what seeps from the ocean thermal vents. Davies has suggested, in more than one book, that any life on Mars shares a common ecosystem with Earth, due to the trade in meteorites between the planets over the aeons. Mentioning this sharing of life between planets produced an outburst from Robert Zubrin, who is an advocate of interstellar transfer of life throughout the Galaxy. A credit to Davies, his response was more interested curiosity than the reflexive dismissal Zubrin seemed to expect. His answer was that we simply don’t know enough to rule out the possibility and they should discuss it more later.

Jon Lomberg

The Benfords encouraged researchers to present in the audience, with divergent points-of-view. These share a desire to bridge the space between the stars, but differ in details of how and why we’ll go to the stars. The next speaker unified the many voices by sharing his sense of wonder at the Universe, through a living work of art – Jon Lomberg [video] and his Galaxy Garden. Long-time readers of Centauri Dreams will know of Jon Lomberg’s artwork for Carl Sagan’s Cosmos in the 1970s and his Galaxy Garden in Hawaii. Having Jon share it with us, a guided-tour in slides, was inspiring and drew multiple rounds of applause from the audience. As Jon put it we can be Citizens of the Galaxy now.

Image: Artist and Galaxy Gardener Jon Lomberg.

Two discussion panels concluded the Symposium. The first, chaired by Jill Tarter, of the SETI Institute, featured Ian Crawford, Robert Zubrin, Geoffrey Landis, Paul Davies and myself. Our theme was “Getting to the Target Stars” but with Jill as the chair we wandered into the search for others who might have made the same journey [video]. Jill gave a brief summary of false-positive detections of extraterrestrial technology, which have proven to have natural explanations.


Image: Jill Tarter gives the lowdown on false-positives in SETI.

The sole exception, the distinctive spectroscopic signature of tritium, has no natural explanation if it is ever detected. With that in mind each of the panelists made suggestions about how we might detect aliens – Robert Zubrin mentioned the distinctive radio output of a starship deploying a magnetic sail, while I suggested the Solar System be searched for dead starships, since not everyone succeeds in their long voyages. A final task was to sum up how we thought humanity would go to the stars. A common feeling seemed to be via robotic proxies, or nanobots. In my opinion, by the time we are ready, the distinction between “human” and “robotic” might be meaningless or arbitrary – thus my quip “Nanobots are people too.”

The final panel [video] was a perspective by the science fiction writers, some involved in the Starship Century anthology – Joe Haldeman, David Brin, Larry Niven, Vernor Vinge – and Jon Lomberg. This was the artistic side of the event, as all these have produced visions of the starship era. The general feeling was that, given the growth in space industry that Chris Lewicki and Robert Zubrin advocated, then we would see the first star-voyagers depart in about 2200, much as Freeman Dyson had extrapolated back in the late 1960s. Some envisioned the unexpected – the discovery of extraterrestrial intelligence near enough to communicate with; breakthroughs in physics that would allow rapid interstellar travel; or, as Allen Steele depicted in his award-winning Coyote series, the rise of a tyrant putting a nation or the world on a crash-course program of starship-building. As always, the future will surprise us, but we can prepare ourselves by listening carefully to the modern-day prophets.


Report from Starship Century

We’re fortunate to have had Centauri Dreams regular Adam Crowl not just as an attendee but a speaker at the recent Starship Century symposium in San Diego. Here Adam, in the first of a two-part report, gives us a look at the speakers and their ideas. With regards to comments, please note: In the last week we’ve had a lengthy discussion of inclusivity in the space community that has absorbed two comment threads. Anyone who wants to continue that discussion can do so in our Facebook group. On this site we need to get back on topic, in this case, the ideas on interstellar flight presented at this conference and where they take us.

by Adam Crowl


The Starship is still about 100 years away, but we will begin building it this century. This was the message that Gregory Benford and his mirror-twin, James Benford, were proclaiming together in San Diego, with the help of notables of both science and science fiction. And me. Just how I got involved is another story. Suffice it to say that I know a lot about starships, at least about every variety that has ever been seriously proposed.

The choice of venue and the timing were serendipitous – the Arthur C Clarke Foundation and the University of California in San Diego (UCSD) had been working together on the Arthur C Clarke Center for Human Imagination, and the UCSD is the alma mater of a surprising number of modern day Science-Fiction writers. Over the month of May a variety of events were scheduled, notably a conversation between Jonathan Lethem and Kim Stanley Robinson on May 14, but the biggest was the Starship Century Symposium. Not coincidentally there is also an associated book, though when I began working on my chapter contribution over a year ago I had no inkling of the event coming up. The Symposium provided a good kickoff for the book, which went on sale the first Symposium day.

The details came together quickly and the Symposium proved to be a credit to the organisers. The event proper was on May 21 & 22, but a UCSD function the night before set the scene, with the Chancellor and Sheldon Brown explaining what the Arthur C Clarke Center was and how it came about. UCSD is the alma mater for a surprising number of contemporary SF writers – not just the Benfords, but also David Brin, Kim Stanley Robinson, Neal Stephenson and many others – so the idea of Arthur C Clarke’s legacy finding a home there seems fitting.

Across the Pacific

I had arrived in San Diego that afternoon (May 20), after crossing the Pacific with a tail-wind for 12 hours, and had shared a shuttle bus to the La Jolla Shores Hotel, where the invited speakers were staying, with John Cramer. I had met John briefly at the Orlando 100 Year Starship (100YSS) conference, but had corresponded with him on-and-off for some time. He gave me a quick update on his retrocausality experiments (see his Alternate View column for details) and then we arrived. I grew up on Queensland’s Sunshine Coast so seeing the Pacific, but looking West, took a moment of reorientation.

Once checked in I needed to stretch my legs so I walked up the nearest street to the local Cafes and shops, only to run into fellow contributor to the book, Ian Crawford – another alien in this strange land of California. We discussed exoplanets and the fate of ocean planets, whether they would dry out or remain drowned, over the aeons. Returning to the hotel to get dressed I ran into Greg Benford – who briefly I confused with his brother Jim, as he was wearing a tie – and had an inkling I might be slightly over-dressed.

As with 100YSS, much of the discussion and interaction happened “off screen”. I spoke to so many people, several of whom told me amazing things, but I then promptly forgot what was on their name-badges. Familiar faces I quickly caught up with, especially Al Jackson, whom Centauri Dreams regulars would know well from Paul’s discussion of Al’s immense contribution to space-flight. Al astounded me by saying he only managed to see one live launch from Cape Canaveral – STS 135 – even though he had worked with many of the Apollo crews in the 1960s. A new face for me was SF writer Allen Steele, whose work I knew of, but hadn’t managed to yet read. A mutual friend, Winchell Chung, has written up much of the technical details of Allen’s novels on his Atomic Rockets website, and has also advised Allen on his more recent works. Other new faces, for me, were the polymath Eric Hughes, who wrote for Wired in the hey-days of Cyber-Punk in the early 1990s; Mark Canter, who is a former editor of Men’s Health magazine and these days writes SF novels with a more anthropological basis, and John Chalmers, an astrobiologist who has worked with Stanley Miller on the chemical origins of life. The audience of Starship Century was of stellar quality, how much more so the speakers.


Image: Left to right, Al Jackson, Allen Steele, John Cramer and Geoffrey Landis. This and other photos courtesy of Jim Benford.

Drivers for Starflight

Day One, May 22, began with breakfast watching the breakers and discussing interstellar matters with James Benford. Instead of the UCSD Shuttle ride, I had a lift with Jim and Allen Steele as another passenger. Arriving, the puzzle was where to sit. With so many luminaries in attendance, one doesn’t just sit next to Freeman Dyson without introduction. Jim, Greg and Sheldon Brown [video] opened the day officially, and I sat back to listen to Peter Schwartz [video], renowned futurist and long term strategist for some very large companies, discuss the scenarios of the future that might get humanity to the stars.


Peter covered three basic scenarios, though many more can be generated. The full details can be found in the Starship Century anthology, but in essence Schwartz saw three ideologies that could launch us to the stars. Firstly, “God’s Galaxy”, which implies a future Earth dominated by religion, sending forth missionaries to the unconverted of the Galaxy. Secondly, “The Dying Earth”, in which we’re seeking a second home, basically the back-story of “Firefly” and countless other SF treatments. Thirdly, “Interstellar Trillionaires”, in which the ultra-rich of a fully developed interplanetary economy launch forth for adventure or curiosity’s sake. Of course, what applies to us might also apply to other civilizations, with the logical implications for Fermi’s Paradox. Peter’s response to that was to suggest that “they” might be too sparsely spread in space-and-time for it to yet be an issue.

Next up was Freeman Dyson [video], who has a deserved reputation as a big thinker, as well as at least one near-miss with a Nobel Prize. In interstellar matters, his seminal popular piece “Interstellar Transport” (1968) described one of the few interstellar propulsion systems we could almost build now – nuclear fusion pulse propulsion. What I hadn’t realised was that the testing ground for “Project Orion”, the USAF/NASA nuclear pulse rocket, was in San Diego – of course, the test models only used high-explosives, but the video available of those tests is quite inspiring.

Since the heady days of the 1960s, Freeman has argued more for biotechnology playing a role in our interstellar plans. His lecture covered several ideas he has produced over the last 50 years, namely plant-derived habitats that we might grow on the cold bodies of the outer solar system, and the most efficient means of getting between the stars – send information. Eventually, he suggests, we might launch “biosphere seeds” to other star systems and grow new habitats for Earth-derived life as well as ourselves. Naturally this had ethical reactions from the audience as well as the rattling of chains by the Ghost of Fermi – if we can do it Out There, why hasn’t Someone done it here? After the lecture, during a break, I suggested to Ian Crawford that we might not know our biosphere’s genome well enough to tell if such a scenario hasn’t happened here.


Image: Freeman Dyson and James Benford in animated conversation.

If Freeman Dyson created controversy, the next speaker, Robert Zubrin [video], practically invited it by daring to suggest that greenhouse warming might be preferable to billions of people living in poverty. Zubrin’s talk covered the economic Big Picture of what was needed to create an interstellar capable civilization, but also provided a chance for Robert to vent spleen about more radical environmental ideologues. Naturally he has a book which covers that particular argument, so I will refer the reader to that for more details. On interstellar matters, he made a powerful case that 100 to 200 years of continued development would see humanity ready to set forth to the stars in the first generation of fusion-propelled starships.

My one quibble was the “Energy at Retail Prices” fallacy being used to estimate the economic scale of interstellar flight – a 1,000 tonne spaceship moving at 0.1c and using energy at 10% efficiency would cost $125 trillion in energy bought at the retail rate of $0.1/kW-hr. The problem is that one doesn’t buy energy for a starship and just charge up the batteries. Instead a starship is more like an energy generator – using either solar energy or fusion fuels – and this requires a wholly different economic measurement. The estimates can vary significantly as a result.


Neal Stephenson’s talk [video] was something else again. Not what I expected from an SF writer at all. Instead of Big Picture discussions, he described a vast 20 kilometer tower that he, and his Arizona State University team, have designed. His talk was thus a detailed look at an advanced theoretical engineering design study in progress. The challenge of such an immense structure, possibly hundreds of millions of tonnes of steel, working in such a changeable environment as the Earth’s atmosphere is fascinating, as is the associated novella in the anthology. But how does it relate to interstellar flight? Naturally the first thing I thought of was as an anchor for a space elevator. Greg Benford suggests another use in the anthology, in his story following as a coda to the Stephenson story. In the current design there is a big empty volume – for future use. A space to fill, for the next generation’s imagination. A reminder, like the Pyramids became, that what one achieves in the present will look different to the people who come after you.