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Deck Hands for a Four Decade Journey

If you were offered a chance to make an interstellar journey, would you take it? How about a garden-variety trip to low-Earth orbit? I’m often asked questions like this when I make presentations to the public, and I have no hesitation in saying no. Though I’m no longer doing any flight instructing, I used to love flying airplanes, but getting into a rocket and being propelled anywhere is not for me. To each his own: I’m fascinated with deep space and hope many humans go there, and you can count on me to write about their missions and robotic ones as well while keeping my office right here on Earth.

The point is, the percentage of people who actually go out and take the incredible journeys and fly the dangerous missions is vanishingly low. But throughout history, there have always been a few intrepid souls who were willing to get into the canoes or the caravels or the biplanes and open up new territories and technologies. Thank God we have the Neil Armstrongs and Sergei Krikalyovs of this world. And somewhere in England there are the relatives of some young 18th Century adventurer who signed up as a cabin boy and wound up living out his life in Australia. People like this drive the species forward and put into action the yearning for exploration I suspect we all share.

Image: Sara Seager, who specializes in exoplanet atmospheres and interiors as the Ellen Swallow Richards Professor of Planetary Science at MIT. Credit: Justin Knight.

I’ve told this story before, but in the past few weeks a high percentage of the people coming to this site are coming for the first time, so I’ll tell it again. Robert Forward was the scientist who more than any other argued that we study methods for reaching the stars, saying that it could be done without violating the laws of physics and would therefore one day occur. Forward’s son Bob told me what happened one night at dinner when he asked his father whether he would get on a starship if it landed nearby and he was asked to go out and explore the universe, with the proviso that he could never come back. Forward’s response was instantaneous: “Of course!”

To which his wife Martha could only reply: “What about us? You mean you would just leave your family and disappear into the universe?” That made Forward pensive for only a moment as he replied, “You have to understand. This is what I have dreamed about all my life.”

MIT’s Sara Seager always manages to work the personal participation question into her talks on exoplanets. She pushes the audience this way and that and it always turns out that there are some people who would go no matter what. Here’s what she told The Atlantic’s Ross Andersen in a recent story, after describing how nuclear pulse propulsion or some kind of sail might conceivably get a spacecraft up to ten percent of lightspeed, which makes for a four-decade journey to the nearest stars:

“…I explain the hazards of living on a spacecraft for 40 years, the fact that life could be extremely tedious, and could possibly even include some kind of induced hibernation. But then I always ask if anyone in the audience would volunteer for a 40+ year journey, and every single time I get a show of hands. And then I say, “Oh I forgot to mention, it’s a one way trip,” and even then I get the same show of hands. This tells me that our drive to explore is so great that if and when engineers succeed at traveling at least 10 percent of the speed of light, there will be people willing to make the journey. It’s just a matter of time.”

I don’t doubt that Seager is right. What she might have gone on to say, if she really wanted to push the point, is that at ten percent of the speed of light, the Alpha Centauri mission that reaches its destination in 43 years is clearly a flyby. Spend more than four decades in transit and then whisk through the target system in less than a day. Would the hands still come up? My guess is that a few still would. A few would probably come up in answer to the question: “Would you go to Alpha Centauri if the only planet in the system turned out to be heat-blasted Centauri B b?” Explorers do this kind of thing — Percy Fawcett didn’t push into the Mato Grosso because he thought it was a clement place to be, nor did Robert Falcon Scott think highly of Antarctic weather.

Seager mentions what Marc Millis always calls the ‘incessant obsolescence’ problem, namely that sending one probe may simply result in its being passed enroute by another probe built later with faster technology. You can keep working that scenario until your head spins (go re-read A. E. van Vogt’s ‘Far Centaurus’ for just one science fictional take on the issue), but waiting for technology to improve gets you nowhere. At some point, you have to launch something, because we learn both through our successes and our failures, and waiting for things to happen can result in stagnation. Pushing the envelope with our crew of hand-raisers is what makes for progress.

Andersen is always a good interviewer, and he homes in on a key issue with regard to interstellar technologies. How do we develop them? Specifically, we would like to wed improved space science to the industries that can benefit from what a space infrastructure can produce, but what kind of industry would benefit from the technologies that can get us to the stars? Noting her belief that the first interstellar missions will be robotic probes, Seager responds:

Right now, I can’t see any connection between capabilities for interstellar travel and industry — at this point, it would purely be for exploration. But we can still benefit if industry decides a low-Earth orbit platform for assembly and launch would be useful. That’s because much of the fuel used for space missions is used to combat Earth’s gravity. If you have a way to assemble these probes in space, you actually have a chance to be more efficient and go faster. It’s conceivable that the private sector would be interested in something like that.

We’re going to be learning a lot more about what the private sector is and isn’t interested in as we experiment with different business models — Planetary Resources comes to mind (Seager serves as an advisor to the company), but ideas for turning a profit in space are hardly limited to asteroid mining. The suspicion here is that we will be unable to get a good read on commercial space interests until we’ve pushed that envelope as well, actually trying mission concepts and business models across a wide front to see what works. But surely Seager is right that low-Earth orbit is a key to the space infrastructure we want to build. Get there, as the saying goes, and you’re halfway to anywhere.

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  • lurscher October 23, 2012, 11:08

    I personally find interstellar flight technology speculation (specially antimatter storage methods) absolutely delightful. However, when one is seriously planning a space roadmap, one must be very careful to not put the carriage in front of the horses. We first need to develop a Sol civilization across our system. Learn what it takes for long-term self sustainability of space cities, either in orbit or in the surface of planets. After that we might start dreaming about taking our chances against the deep abyssal void, and whoever go, machine or human, will go ready to permanent settlement.

  • Dean Stell October 23, 2012, 11:36

    I love your blog and read it every morning. Always fun….

    I wonder if this spirit of exploration is somehow at odds with government-sponsored space travel. Maybe this isn’t the case, but it seems like space agencies are very risk adverse and that will run counter to the risks that you probably have to take to really explore. Think of how many humans died exploring the world’s oceans or how many Europeans died exploring Africa. Would they have been able to do that exploration in an era when a Space Shuttle disintegrating grounds the fleet for a couple years? With the media watching like a hawk and airing out every failure?

    It’s part of what makes me optimistic about things like Space X or other commercial spaceflight groups. Eventually one of these groups will put some people into orbit that aren’t NASA astronauts going to the ISS……they’ll be employees of some company going to mine asteroids or something…..riskier, but kinda similar to working on an oil rig in some of the nasty places on Earth. These groups will lose some of these people and the first time that happens…..it’ll be big news, but it will quickly die down and the next group of explorer/workers will move the project forward which will be more in keeping with the risk taking nature of the explorers.

  • Paul October 23, 2012, 11:52

    Flight instructing is a pretty tough assignment.
    I fly airliners, and the hours and time zones, etc. are pretty tough. But being responsible for sending up someone for a 1st solo, and finding a way to get them to understand how to do something is especially difficult.
    I miss light aircraft, a lot, but I don’t miss instructing. It’s a special calling.
    I also agree on the negatives of a 50 year deep space journey. Fortunately, as you say, there are people that will do it.
    I will hold out hope for that guy that wants to isolate a bubble of space time and go REALLY fast in normal time.

  • Alex Tolley October 23, 2012, 12:43

    People will always raise their hands if the question is hypothetical, but actually following through is another matter.

    Interstellar flight is not the same as global exploration. The rewards may be known (possibly) but the travel times are beyond anything explorers have tried, other than the Biblical story to Moses and the tribes of Israel wandering the desert. Would someone willingly stay in a [comfortable] prison cell for 40 years with maybe the possibility of getting out for a romp in 40 years? I’m skeptical. What is the reward? A dead world with the glory of setting historical footprints that cannot be bathed in back home? A living world that is off limits due to some “prime directive”?

    A one way trip to the Moon or Mars is different. The journey time is short. You can communicate with Earth. There is a hope you can build something on arrival to make life more comfortable and to attract new explorers.

    Now if the interstellar flight had a short subjective time, then that might be different, always bearing in mind that the civilization on Earth might have changed in unpredictable, and possibly antithetical ways. So if humans are to travel to stars, and possibly colonize suitable worlds, I do think that it will require ways to reduce the subjective and biological time to something short, not more than a year or two.

  • Wojciech October 23, 2012, 13:29

    It will be a strange future, when you will have a space station, maybe an outpost on the moon and some experimental asteroid being mined, while at the same having pictures of thousands of alien worlds, perhaps even with signs of biosphere.
    It would be interesting to analyze what would be the effect of having knowledge of other-living-worlds, combined with lack of serious space infrastructure.
    For some no doubt it would be depressing, but it could motivate others.

  • Jay Real October 23, 2012, 13:37

    It’s only partially touched on, but I think having people in stasis (and not just like a mild coma, which is what scif-fi typically shows, I’m meaning Alcor-style cryonics) entirely until they arrive. They would then recover for several months, then maybe a few years worth of work, sending the info back to earth, and then go back to stasis, arriving back at earth, say, 85 years later – BUT, able to live out their lives in the future. That is the most feasible solution.

    I believe there are a number of pioneers willing to take the risk and wake up in the future, much more than those who would simply sacrifice their lives for science.

    Also, that’s not getting into the fact that you have so much less materials to ship to keep people alive, making it more cost effective, and the likely fact that if everyone is up, they’ll likely break something, even by accident.

    So, it does not have to be a one-way trip once we get cryonics (specifically vitrificaiton) worked out in the future.

  • Leon October 23, 2012, 14:01

    Sign me up!

    Recently I read an article about a Dutch reality show that, in some years, might offer one-way tickets to Mars. I had to ask myself if I would do it given the chance. I’m still not sure if I would or not.

    I would, however, jump at the chance of a one-way ticket to another planetary system. Why would I choose the interstellar relocation but perhaps not the interplanetary one? It has something to do with the greater distance and the higher risk — it seems more adventurous. Also, with the interstellar trip, I would have something to look forward to for most of my life and by the time I actually experienced it, my life might be close to over due to my age.

  • Paul Titze October 23, 2012, 20:05

    If the mission is about gathering scientific data there’s no real need to send people, if there are plans to setup a station or an outpost on the exoplanet then yes send them. Most missions ie scientific studies, data collecting etc can be done by robots/probes. Sending people on a 40 year mission presents many problems, will they survive the cosmic radiation in that time? Even on Earth people haven’t been locked up on a ship for 40 years at sea without shoreleave so the crew who volunteered at first might seem keen and enthusiastic however after a month or so and all the hype, the reality of the mission starts to sink in. After a few years they might have serious thoughts going back home even if the ship is working properly. A solution to this would be to put the crew on cryostasis for the trip.

    Cheers, Paul.

  • Josh Haigh October 23, 2012, 20:50

    Regarding short subjective travel times, I think this is only an issue for those who want to return. I can certainly imagine groups who wish to escape persecution (mormons?) or state control (anarchists/ free-marketeers) who would regard the fact that it’s one way and takes a long time as being very large plus points.

  • Kathleen Toerpe October 23, 2012, 21:24

    The trick, I think, is to make everyone who raised their hand – even if they wouldn’t really leave family and friends for such a dangerous one-way mission – feel part of the journey and the adventure nonetheless. Only 530 or so people have ever been in space; we rationally know that few of us who walk on Earth will ever touch foot on another planet. But we can look up! We can say to ourselves, “What if…” If we can tap into that sense of wonder and enthusiasm that inspired people to raise their hands, to be willing to even consider (at least hypothetically) leaving all they love behind to courageously explore another star system, even risking loneliness and death, then perhaps we can begin to solve our problems of financing for NASA, of encouraging students to pursue STEM (or better yet, STEAM) courses, and for advocating to leaders of both parties to commit to exploration. Let’s find out why those people raised their hands and why some hands stayed down and maybe we will find out where we need to begin to prepare ourselves and Earth to be an interstellar civilization. (Maybe I just talked myself into a new research project?)

  • David October 23, 2012, 22:34

    As a biologist I would say cryonics is tougher than 10 percent light speed so i am with Marc Millis and Paul Titze…lets work on an unmanned probe to go 5-10% light and build the near Earth Moon asteriod and Mars infrastructure to do it and it sounds like Space X is ready to do it
    BTW I would do a suboribtal. Thats it for me

  • James Jason Wentworth October 23, 2012, 22:48

    Paul Gilster wrote:

    [Though I’m no longer doing any flight instructing, I used to love flying airplanes, but getting into a rocket and being propelled anywhere is not for me.]

    I was surprised to read this, Paul; you wouldn’t try even a suborbital hop aboard a Virgin Galactic SpaceShipTwo spaceplane? Also:

    This type of spaceflight, using winged rocket ships, may even become common for point-to-point transcontinental and intercontinental travel, as Wernher von Braun, Hideo Itokawa, G. Harry Stine, and Hsue-Shen Tsien dreamed. Space.com has reported that a Titusville, Florida company called Rocket Crafters, Inc. is developing a jet *and* hybrid propellant rocket-powered suborbital primary trainer spaceplane called Sidereus, which is intended for transcontinental surborbital flight. It will take off and land under jet power like a conventional airplane. In addition:

    The Space.com report said that the Front Range Airport in Watkins, Colorado, which wants to be the home of Spaceport Colorado, has signed a letter of intent with Rocket Crafters, Inc. for operations of their vehicle at the airport. The suborbital flights of Sidereus are planned to occur between a Spaceport Florida airfield and the Front Range Airport. As well:

    G. Harry Stine described and illustrated such transcontinental winged rocket ships (including how they would be integrated into the existing air traffic control system) in considerable detail in his 1957 book “Earth Satellites and the Race for Space Superiority.” The improvements in propulsion, guidance systems, electronics, materials, and structures that have occurred since he wrote his book would make such suborbital spaceliners and cargo vehicles even more practical today. These vehicles will likely be the first tier of the (eventual) solar system-wide space infrastructure that will make interstellar probes and starships technically feasible and financially sound propositions.

    — Jason

  • Joy October 24, 2012, 3:04

    Speaking for the hand raisers, perhaps we differ from the general population in having a visceral understanding that life is a suicide mission anyway. Why not spend our limited days exploring?

  • Robert Horley October 24, 2012, 6:21

    I think the issue for long term spaceflight is communication with Earth. If you’ve got a community on the ship and good communication with loved ones on Earth, it’s going to feel like you are still part of Earth. A bit like an isolated village with good internet.

  • ljk October 24, 2012, 9:48

    Earlier articles on sending people on one-way missions to Mars had plenty of volunteers raising their hands, although how many of them would actually be qualified for such an adventure is another matter:

    http://www.universetoday.com/13037/a-one-way-one-person-mission-to-mars/

    Maybe sending trained soldiers like in the old days of colonization is the smart way to ensure success:

    http://www.universetoday.com/14544/one-way-mission-to-mars-us-soldiers-will-go/

    To quote from the above article:

    Ruth sent an email to Space.com’s Anthony Duignan-Cabrera, which was posted on the LiveScience blog: “Here is an idea: Send battle-hardened, strong-minded soldiers and marines on the long trips into space. We are conditioned to live with the bare minimal (of) life’s necessities and are trained to be prepared for … the worst conditions that any environment could throw at us. Hell, me and my men will go, set up a colony somewhere and await colonists to arrive.”

    and…

    Ruth admits that other might see sending soldiers into space as more like an invasion or occupation than exploration. “To those who share this concern, consider this for a moment and ask yourself, who else?” Ruth asked. “Who else has the mentality to volunteer to face certain danger and possibly death, thousands of miles away from their homes? I could think of a few hundred thousand that do it everyday across this planet.”

    My mantra has been “Robots are for exploring space, humans are for colonizing space.” Of course the two have and will work together to achieve their goals, but as robotics, sensors, and computers improve, spreading humanity into the galaxy to ensure our species survival will be the only logical reason to place our descendants out there.

    We may not even need sample return missions for such places as Mars with the way technology is advancing:

    http://www.universetoday.com/98094/mars-sample-return-mission-naaah-just-beam-back-martian-dna/

    All the above applies to interstellar travel. Our machines will be so sophisticated and practical by the time we can launch an actual star probe that humans will be excessive baggage for a pure exploratory mission. And by the time we can ply the Milky Way, will our children still require rescuing as we seem to need at present?

    There are a number of dated paradigms regarding interstellar flight that need to be re-examined and readdressed. Especially this idea that if we find an Earthlike exoplanet we should send out a colonization effort as soon as possible. An Earthlike world cannot be Earthlike without life somehow being involved. Even if there is no intelligent life there (and just go ahead and try to define that parameter with an alien being), does this mean we can just move in and trample on its equivalent of the grass?

    Interstellar travel and the galaxy at large are not going to be like an episode of Star Trek – and that is probably a good thing.

  • Alex Tolley October 24, 2012, 10:27

    @Robert Horley “A bit like an isolated village with good internet.”

    More like an isolated village with very slow postal service, i.e. years for delivery.

  • Alex Tolley October 24, 2012, 10:33

    @Joy ” visceral understanding that life is a suicide mission anyway”

    How so? You have an unbroken line of ancestors going back billions of years. Now if your genes had an extremely low opportunity to replicate, then you might have a point. But on earth, most human individuals can replicate their genes and ensure the future. On a star ship, that is a lot less certain.

  • Greg October 24, 2012, 12:44

    Joy said, “Why not spend our limited days exploring?”

    Amen to that!

  • Astronist October 24, 2012, 19:53

    I would go. But the way I plan it, it won’t be a dangerous voyage of exploration. I’ll be living in normal comfort in a town-sized community of people (tens of thousands) with all normal amenities for a comfortable human life. The vehicle will be perfectly safe, having the technological heritage of several centuries of space colony development and large-scale use, and will be joined by other vehicles of the same type for greater security as the voyage goes on. I will live my life much as I do now in Oxford (only without the bad weather), and will toast with champagne the thought that my descendants a few generations hence will resume space colony construction at the destination, along with careful non-invasive observation of any Earth-analogue planets which may happen to exist there.

    Stephen

  • Bounty October 24, 2012, 20:06

    Mars Science Labratory doesn’t know the difference between a spec of Mars and a spec of fallen MSL. Todays robots are fools. I wouldn’t trust one to a trillion dollar mission to end up following around a spec on the lens it thinks is a planet. meh…. Hubble? No, these mechanical beasts need us around still.

  • Eniac October 24, 2012, 22:24

    James Jason Wentworth:

    This type of spaceflight, using winged rocket ships, may even become common for point-to-point transcontinental and intercontinental travel, as Wernher von Braun, Hideo Itokawa, G. Harry Stine, and Hsue-Shen Tsien dreamed.

    I agree with this completely. I would even go a little further in saying that the more recent visionaries of this field (Burt Rutan, Rich Branson and the like) have been quietly planning way beyond space tourism for the real prize: the 90 minute trip from New York to Shanghai for busy businesspeople.

    That’s why these designs have wings and safe propellants: They must be suitable for regular airports near population centers.

  • Arecibo October 25, 2012, 0:30

    @Alex

    Life is suicide means that you are living just waiting for death to come. It’s not about genes or humanity or civilization, it’s about each individual’s life.

    Yes, your sons can continue your dream to go to other stars, but it’s THEM, not YOU.

  • Alex Tolley October 25, 2012, 14:22

    @Areceibo
    You may have missed the intentional reference to the “selfish gene”.
    “Life” can be very broadly interpreted. :)

  • Alex Tolley October 25, 2012, 14:27

    @Astronist
    Your life in Oxford is highly dependent on a global economy and life support system. Your star traveling “Oxford with good weather” would be completely self sufficient and of necessity quite resource limited. Freedom of action might also be very limited. Your offspring might not be quite so happy as you to be on board such a limited system, especially when they read if the solar system culture and economy they were never given a chance to experience, and without possibility if returning to.

  • Wojciech October 25, 2012, 15:21

    Alex Tolley,
    That is why two-generational ships crewed by highly ideological/religious groups would probably have the best chances.
    In theory you could reach AC in two generations if the trip would take 40 years, allowing for the older generation to continue its influence.
    As to younger generation, I don’t think this is a problem as big as people sometimes claim. People tend to identify with their group(of course there are always dissenters) and take pride in achievements of their country/city/nation. It only requires good social techniques to achieve this.

  • Astronist October 25, 2012, 19:27

    @Alex Tolley
    I agree: the interstellar travellers would never be able to visit the Solar System, just as almost everybody in the Solar System would never be able to leave it, and the majority of them will never visit Earth in person (and just as I have never visited the African savannah where our species first evolved). One has to make the best of the circumstances into which one is born.

  • Christopher Phoenix October 25, 2012, 20:16

    @Astronist

    I would go. But the way I plan it, it won’t be a dangerous voyage of exploration. I’ll be living in normal comfort in a town-sized community of people (tens of thousands) with all normal amenities for a comfortable human life.

    Sounds suspiciously like a fantasy too me- what makes you think that the first interstellar voyages will be anything other than a dangerous voyage of exploration, or that the ships will be gigantic space cities in which tens of thousands will live in comfort? The payload of a starship will probably be rather limited, encouraging the designers to lower the mass of the habitation area. Instead of sending a vast crew, they could send a smaller crew of “caretakers” with access to banks of genetic material to avoid inbreeding. Perhaps the ship won’t be multigenerational at all, and the astronauts use anti-aging and subjective-time reducing technologies like induced hibernation, slowed metabolism, etc. to survive the lonely journey. Think Planet of the Apes, not Oxford in Spaaace…..

    The vehicle will be perfectly safe, having the technological heritage of several centuries of space colony development and large-scale use, and will be joined by other vehicles of the same type for greater security as the voyage goes on.

    “Perfectly safe?” Not very likely. Interstellar flight will be totally unlike living in a space colony orbiting near Sol- such a colony does not have to face the rigors and isolation of interstellar flight and can easily trade with nearby colonies and planets. They can even call for help if something goes badly wrong. An isolated slowboat can’t. Star voyagers will face long-term exposure to cosmic rays (including, at high fractions of C, induced cosmic rays), potentially fatal impacts with space debris, and the need to maintain a fragile spacecraft and life support system without support from Earth. I don’t see any reason to expect an interstellar journey to be anything other than a dangerous voyage of exploration. The trip is dangerous, and you’re going somewhere no human has ever been…

    I will live my life much as I do now in Oxford (only without the bad weather), and will toast with champagne the thought that my descendants a few generations hence will resume space colony construction at the destination, along with careful non-invasive observation of any Earth-analogue planets which may happen to exist there.

    Assuming that the starship is spacious enough and luxurious enough to resemble Oxford, rather than being an isolated tightly-controlled community, and that you will have enough resources at the destination to play nice with local aliens, and that your goal is not colonizing Earth-analogues- and where did you get the champagne, anyway? Is there a vineyard on board?

    One thing that’s always annoyed me are people conflating space colony design with starship design. Space colonies have easy access to raw materials, sunlight, and support from Earth- and unlike a ship, they can be built at enormous sizes without much worry about acceleration forces. A ship, on the other hand, will be built around its propulsion system, rather than being an O’neil Cylinder with an ion engine or solar sail added as an afterthought. The ship will have to endure acceleration forces (the amount will depend on the mission profile), last for decades or even centuries, and probably be limited to contain only what is absolutely necessary to carry out its mission.

  • Alex Tolley October 26, 2012, 9:38

    @Astronist
    If you wanted to, you could visit the African savannah. The savannah isn’t that attractive compared to a town, especially if you want to live there, rather than just visit. Removing the possibility is a different matter. On a generation ship, it might be more akin to “how are you going to keep them down on the farm?” scenario, except that the exciting city is not reachable. Yearning for something lost might lead to disruptive behavior on a ship. I wouldn’t bet on it being that cosy. Then what?

  • GaryChurch October 26, 2012, 16:12

    “As a biologist I would say cryonics is tougher than 10 percent light speed”

    Well yes, if you just freeze someone and expect to repair the massive cellular damage later. The trick is to drop and raise the temperature without forming those ice crystals. A great deal of research lately on the properties of water makes it clear that doing so breaks no laws of physics.
    I expect any day for the news to break that some people in lab somewhere have successfully frozen and revived a dog or a monkey. If I am right, that is going to be the most important event in human history. Everyone will suddenly realize that the old enemy is on the run. The massive resources we expend on…..everything except medical research, will overnight be rededicated to building storage facilities and reversing aging.

    As for commercial space and LEO being “halfway to anywhere”; I am not drinking that kool-aid. There is no flexible path. It is very narrow and straight forward and it starts with radiation shielding. 14 feet and several hundred tons minimum according to Eugene Parker. I believe him. If you start with that you have to accept nuclear propulsion and that means a moonbase since nuclear activities in the magnetosphere will not be acceptable. Then there is the matter of which nuclear propulsion scheme. Bombs are the only practical method. Most people cannot wrap their heads around that fact.

  • Wojciech October 27, 2012, 8:28

    “It is very narrow and straight forward and it starts with radiation shielding. 14 feet and several hundred tons minimum according to Eugene Parke”
    Or you could use mini-magnetosphere plasma propulsion (M2P2), providing you with protection.
    http://news.nationalgeographic.com/news/2008/11/081104-magnetic-shield.html

  • GaryChurch October 27, 2012, 14:01

    M2P2 has not worked out; probably because there is no way to couple the vehicle with the sail cloud. As for providing protection, nothing stops the heavy nuclei component of cosmic radiation except mass and distance. It would require a plasma cloud the thickness of the Earth’s atmosphere (at least). That is what protects us by the way.
    There are plenty of people with a space tourist agenda that dismiss radiation mitigation as “trivial.” It is the big lie. Radiation is square one and everything begins with shielding space travelers or you will not have any space travelers.

  • Wojciech October 27, 2012, 17:49

    There are many ways to shield spacecraft from radiation that do not require mass, this article for example says that it can be done with magnetic shield. We will have to wait for prototypes of such spacecraft until we know for sure
    http://engineering.dartmouth.edu/superdarn/downloads/JSR09.pdf

  • Avatar2.0 October 28, 2012, 8:19

    GaryChurch
    “As for commercial space and LEO being “halfway to anywhere”; I am not drinking that kool-aid. There is no flexible path. It is very narrow and straight forward and it starts with radiation shielding. 14 feet and several hundred tons minimum according to Eugene Parker. I believe him.”

    14 feet of shielding? For a radiation environment equivalent to many inhabited regions on earth, you only need substantially thinner shielding.

    High-altitude pilots – little effects from radiation from a lifetime of flight.
    Space station astronauts – idem.

    Personally, I’m not drinking the radiation ‘here there be dragons’ kool-aid.

  • Avatar2.0 October 28, 2012, 8:27

    Alex Tolley
    “If you wanted to, you could visit the African savannah. The savannah isn’t that attractive compared to a town, especially if you want to live there, rather than just visit.”
    For most humans – they most definitely could not visit – insert tourist attraction with only historic/nostalgic value. They would lack the necessary means – either economically or politically. Indeed, most humans travel very little in their life-times.
    No disruptive behavior due to it in evidence.

    “Removing the possibility is a different matter. On a generation ship, it might be more akin to “how are you going to keep them down on the farm? scenario, except that the exciting city is not reachable. Yearning for something lost might lead to disruptive behavior on a ship.”
    For most of human history, the exciting city was not reachable. No disruptive behavior due to it.

    I’m not drinking the ‘humans are delicate flowers and need a copy-cat of earth/need freedoms, possibilities beyond those available to present humans to survive’ kool-aid, either.
    The entirety of human history decisively proves the opposite.

  • GaryChurch October 28, 2012, 16:14

    “There are many ways to shield spacecraft from radiation that do not require mass,”

    There is no way to shield space travelers from heavy nuclei except mass and distance. The generic term radiation is often misused in this way. Most radiation is easy to shield against. No this component of cosmic radiation.

    “I’m not drinking the radiation ‘here there be dragons’ kool-aid.”

    LEO is an entirely different radiation environment than deep space. The arguments against heavy nuclei being especially dangerous are tainted with examples of radiation exposure in the upper atmosphere or LEO. The truth is that without the mass of the earth and the magnetosphere, exposure is substantially increased and for mult-year missions this is unacceptable. Partial shielding causes even more secondary secondary radiation.
    The only solution is a massive shield.

  • Alex Tolley October 28, 2012, 22:17

    @Avatar2.o – there can only be disruptive behavior if you know about the place not available. For most of human history, people were hugely ignorant of anything but their local environment. But once you know…
    The resulting behavior doesn’t need to be disruptive, it could take many forms, but that doesn’t mean that it is acceptable to remove people from the environment that would have offered them the most opportunities.

  • S. O'Brien October 28, 2012, 23:36

    @Gary, who said, “M2P2 has not worked out; probably because there is no way to couple the vehicle with the sail cloud.”

    What is the basis of this statement? I wasn’t aware that this technology had been deemed impractical, or whatever. What research are you referring to?

    Thanks.

  • Avatar2.0 October 29, 2012, 11:14

    GaryChurch
    “LEO is an entirely different radiation environment than deep space. The arguments against heavy nuclei being especially dangerous are tainted with examples of radiation exposure in the upper atmosphere or LEO. The truth is that without the mass of the earth and the magnetosphere, exposure is substantially increased and for mult-year missions this is unacceptable. Partial shielding causes even more secondary secondary radiation.
    The only solution is a massive shield.”

    Earth shields LEO astronauts and high attitude pilots from, at most, 1/2 of the heavy nuclei radiation/radiation in general. Cut in half their exposure and you STILL get a significant amount of time exposed to radiation.
    As said – little effects from it.

    As for the magnetic field of Earth – it is 25 to 65 microteslas near the surface of Earth. Significantly weaker near orbit.
    It is quite easy (in terms of energy and mass used) to recreate a magnetic field so weak around a spaceship.

  • Avatar2.0 October 29, 2012, 11:25

    Alex Tolley
    “there can only be disruptive behavior if you know about the place not available. For most of human history, people were hugely ignorant of anything but their local environment. But once you know…”

    People knew very well – then or now – of the tourist attraction beyond financial/political/status/etc reach.
    They could care less – then or now; this was always a luxury, it never motivated much.
    People always cared FAR more about having an adequate standard of living.

    “The resulting behavior doesn’t need to be disruptive, it could take many forms, but that doesn’t mean that it is acceptable to remove people from the environment that would have offered them the most opportunities.”

    What constitutes most opportunities?
    Staying on an overcrowded Earth, with no chance of being more than a cog in the machine? Everything constrained by rules and regulations, in order not t0 upset the multitude near you?
    Or the chance to participate in something truly great? To live as an important part of a wealthy community?

    Parents always make these choices for their children – until the children mature. It is their responsibility and their right.
    And you are mistaken if you think your view of what constitutes “most opportunities” has some kind of right to this title.

  • GaryChurch October 29, 2012, 13:44

    “at most, 1/2 of the heavy nuclei radiation/radiation in general.”
    Uh huh. That means you get twice as much in deep space.

    d”It is quite easy (in terms of energy and mass used) to recreate a magnetic field so weak around a spaceship”

    Uh huh. But since the magnetosphere brushes the surface of the moon at times, the amount of radiation it deflects across that distance is going to be a little more than around your spaceship. You think? Anyway, the amount of heavy nuclei it deflects just might be enough to make space travel impractical without a massive shield.

    The trouble is we dont know. We do know that heavy nuclei is 300 times more damaging to dna than other particles and causes large amounts of secondary radiation when hitting anything that does not stop it completely. In any case, the best bet for multi-year missions and any future presence in space is to just accept what we evolved to thrive in and duplicate those conditions. One gravity and similar radiation exposure. We cannot go wrong going this way- going the other way is almost certain to fail.

  • GaryChurch October 29, 2012, 13:51

    “M2P2 has not worked out; probably because there is no way to couple the vehicle with the sail cloud.”

    What is the basis of this statement? I wasn’t aware that this technology had been deemed impractical, or whatever. ”

    We would have to ask Dr. Winglee about his plasma sail. I was very excited about it when I first read about it. The only basis I have for saying it has not worked out is that……it has not worked out. There have been no experiments in space and if it held any promise we would have seen far more activity. Unless it has been classified and is now a conspiracy theory.
    I hope I am wrong- it is a super cool concept. But how a cloud of plasma can drag a spaceship along with it has always been the main question and I do not think it has been answered.

  • Avatar2.0 October 29, 2012, 16:53

    GaryChurch
    “That means you get twice as much in deep space.”
    As I said: Earth shields LEO astronauts and high attitude pilots from, at most, 1/2 of the heavy nuclei radiation/radiation in general. Cut in half their exposure and you STILL get a significant amount of time exposed to radiation. With few ill effects to show for it.

    “But since the magnetosphere brushes the surface of the moon at times, the amount of radiation it deflects across that distance is going to be a little more than around your spaceship. You think? Anyway, the amount of heavy nuclei it deflects just might be enough to make space travel impractical without a massive shield.”
    Again, as said: As for the magnetic field of Earth – it is 25 to 65 microteslas (that’s quite weak) near the surface of Earth. Significantly weaker near orbit.
    And WAY weaker near the moon.

    If a magnetic field as weak as the one near Earth’s moon is enough to bend the trajectory of heavy nuclei radiation sufficiently in order for them not to hit installations in LEO (as opposed to bending them fractions of a degree), then you can take an industrial magnet to shield your ship and never have to worry about this heavy nuclei radiation again – the shorter range will be more than compensated by the VASTLY stronger magnetic field.

    The case for ‘heavy nuclei radiation is a death trap’ is supported by few, if any, convincing arguments.

    Can this radiation increase the risk of cancer later in life? Probably. That’s it – that’s what the known facts support.

  • GaryChurch October 29, 2012, 17:33

    “Can this radiation increase the risk of cancer later in life? Probably. That’s it – that’s what the known facts support.”

    Go into deep space for several years of lights flashing in your field of vision- which means holes are being blown threw your brain and your DNA is being zapped-and it is not going to have a happy ending. We are going into space to live and thrive, not be irradiated and waste away in zero gravity.

    As I said, duplicate the conditions we have on Earth, which is a simple problem of shielding and engineering artificial gravity, and all is well. But try and go cheap and accept radiation exposure, zero gravity debilitation, mutated pathogens, even the reduced effectiveness of anti-biotics after exposure- and you are bound to fail.
    I would rather win.

  • GaryChurch October 29, 2012, 17:50

    I dislike posting over and over again and arguing about radiation and other facts of life in space- but I have never been able to avoid it on these forums because of the tourists.

    It really irritates the heck out of the Musk worshippers who think they are going to retire on Mars when someone comes along and starts criticizing the private space infomercial. Sorry.

    Radiation is not trivial- it throws a wrench in the whole privates space panacea because it means chemical propulsion is not going to open up the solar system to colonization. Only vast governmental resources can build atomic spaceships that can establish colonies. Sorry.

    The space tourist fad will collapse soon enough when people realize that subsidizing billionaut space station vacations is not going anywhere except in endless circles at very high altitude. Low Earth Orbit is a dead end and above the Van Allen belts space is not an ocean- it is vaccuum seething with radiation.
    We have to deal with the fact that physics has not changed since the 1960’s and material science has provided no wishalloy. Their is no unobtainium on Pandora and radiation IS square one no matter how many people keep saying their is no data and implying that because of this there is no hazard. Dr. Eugene Parker seems to think it is a problem. I believe him over any public relations spin doctor statements or private space mantra recitations.

  • S. O'Brien October 30, 2012, 5:11

    @Gary: I am finding papers about M2P2 from as recent as 2011 which suggests to me that it is still a technology of interest. That it is not being pursued vigorously doesn’t say much, since there are plenty of promising technologies that are largely ignored. My impression is that moving beyond numerical studies is quite difficult because of the scales involved (e.g., a magnetosphere measured in km).

    Just reading abstracts at the moment, but here are some papers of interest that I’ve looked at. Plenty more out there.

    G. Herdrich, et al., “Advanced plasma (propulsion) concepts at IRS” (2011)

    M. Pfeiffer, et al., “Assessment of a Numerical Approach Suitable for the M2P2 Problem” (2011)

    H. Yamakawa, et al., “Magneto-plasma sail: An engineering satellite concept and its application for outer planet missions” (2006)

    A. Barrie, “M2P2 – Using Variable Power Radial Thrust for Interplanetary and Interstellar Travel” (2006)

    T. Ziemba, et al., “Efficient plasma production in low background neutral pressures with the M2P2 prototype” (2003)

    R. Winglee, et al., “Simulation of mini-magnetospheric plasma propulsion (M2P2) interacting with an external plasma wind” (2003)

  • GaryChurch October 30, 2012, 14:34

    “it is still a technology of interest.”

    I hope you are right.

  • Moriarti November 1, 2012, 0:48

    About the radiation issue…

    By the time we’re sending people to Alpha Centauri at 10% c, we will also have made a lot of progress is medical science. Conceivably, we might have largely cracked the issue of targeting specific cells with drugs, using genetic medicine, and have a large and extensive medical database detailing all the ways cancers can form and evolve. Basically, we might have cures for cancer that can be formulated on the fly in the spaceship. Just crawl in the autodoc.

    When that happens, I think we’d just stop caring about radiation. The little light spots in your eyes would still be creepy though.

  • Avatar2.0 November 2, 2012, 6:01

    Moriarti
    “About the radiation issue…”

    In his last posts on the issue, GaryChurch expanded on impressionistic arguments (the little light spots in your eyes) and “because I say so” type rhetoric.
    Neither of which are convincing arguments for his stated point (radiation is a show stopper).