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NASA Space Science

Ex-Astronaut Developing Plasma Rocket To Revitalize NASA 277

TechReviewAl writes "Former astronaut Franklin Chang Diaz believes that the private sector can revitalize NASA, and his company is developing a plasma rocket to back up that claim. Chang Diaz argues that private industry can be used to develop much of the basic technology needed for space exploration, allowing NASA to focus on more sophisticated and critical components. His company, Ad Astra, is developing a variable specific impulse magnetoplasma rocket (VASIMR) that will be used to reposition the International Space Station. Last week, the rocket passed an important milestone in testing — reaching 200 kilowatts (enough to move the ISS). A video of the rocket can be seen on Ad Astra's site."
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Ex-Astronaut Developing Plasma Rocket To Revitalize NASA

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  • Awesome. (Score:4, Funny)

    by nametaken ( 610866 ) on Monday October 05, 2009 @01:59PM (#29647293)

    Bonus points for the space invaders noises it apparently makes.

  • Summary is incorrect (Score:3, Informative)

    by Tekfactory ( 937086 ) on Monday October 05, 2009 @02:06PM (#29647415) Homepage

    Since the ISS only has 120-130 Kilowatts of Solar Panels, running a 200 Kilowatt motor would be difficult.

    Also Kilowatts though stated in the article aren't really a measure of thrust.

    The engine can operate at different levels UP TO 200 kW, but would probably have to use about half that because of the stations limitations. Though if the Motor can use waste hydrogen from the Fuel Cells/Ox Generators they are estimating it would save NASA bringing up fuel for reboosts. (From the Proposal/white paper on VASIMR)

    • by Tekfactory ( 937086 ) on Monday October 05, 2009 @02:14PM (#29647509) Homepage
    • Batteries to give it the electricity it needs maybe?
    • Re: (Score:3, Informative)

      by Robotbeat ( 461248 )

      Thrust can be calculated by the power and the ISP:
      I think it's something like this:
      Thrust=Power*2/(effective velocity)
      or
      Thrust=Power*2/(ISP*9.81m/s^2)

      So, if the power is 200kW and ISP= ~3000s (assuming 100% efficiency, where efficiency is probably more like 65%):
      400,000W/(30,000 m/s)=13 Newtons

      So, a thrust of 13 Newtons is possible at the low end of ISP. And, actually, thrust decreases with ISP, so ten times higher ISP (30,000s) would be about 1 Newton of thrust at 200kW.

      • So, if the power is 200kW and ISP= ~3000s (assuming 100% efficiency, where efficiency is probably more like 65%): 400,000W/(30,000 m/s)=13 Newtons

        So, about as much thrust as an Estes D12 motor, then.
      • Re: (Score:3, Interesting)

        I think ion thrusters would be a better way to go for ISS boosting.

        These [esa.int] calcs show the drag force on the ISS is about 0.25N.

        These [wikipedia.org] tables show that to get 250 mN thrust you are going to need ~10 kW of constant electrical power. That is 8-ish % of the ISS available electrical power. It seems very do-able.

        Possibly ISS electrical power is so stretched that using it to boost is considered a waste. Certainly it is possible without VASIMR.

    • Re: (Score:3, Informative)

      by ender06 ( 913978 )

      Since the ISS only has 120-130 Kilowatts of Solar Panels, running a 200 Kilowatt motor would be difficult.

      I am sorry to go on a rant about this, but as someone who works on solar power on a daily basis, I am sick of people assuming that since something uses solar power to generate the electricity, that it will only work when the sun is shining. Ever heard of batteries? Do you honestly think that the ISS is up there, without batteries, which allow a system to draw more instantaneous power than the solar panels can supply, but can be recharged later when the system isn't drawing so much power?

      I worked on the s

  • by TheKidWho ( 705796 ) on Monday October 05, 2009 @02:07PM (#29647421)

    AFAIK they have been working on VASIMR for over a decade now... This isn't exactly "news"

    • by MozeeToby ( 1163751 ) on Monday October 05, 2009 @02:36PM (#29647799)

      A non-chemical rocket that can produce that level of thrust is absolutely news, it has the potential to open up the solar system. Personally, I'd rather see research and developement into ground to orbit launch technologies, but this is a big part of moving things quickly from one part of the system to another.

      To be fair, the title is what is wrong, it should be "VASIMR Tested at Full Power" not "VASIMR under developement".

    • by CarpetShark ( 865376 ) on Monday October 05, 2009 @02:40PM (#29647851)

      AFAIK they have been working on VASIMR for over a decade now... This isn't exactly "news"

      No, no, no. These VASIMR experiments are entirely new. You must be thinking of the old VALKILMER experiments.

    • I think my thought was more specifically "Oh God, not another VASIMR story."

      I'll get excited when I see flight hardware, otherwise its just another slightly vaporish technology. The vapor is made particularly thin by its dependence on other development, specifically the very high power requirements that are likely to require advancements such as space-based nuclear reactors. From what I know, without this kind of power, it will be little more than an incremental improvement on current flight-proven EP me

    • by Sebilrazen ( 870600 ) <blahsebilrazen@blah.com> on Monday October 05, 2009 @02:47PM (#29647949)

      AFAIK they have been working on VASIMR for over a decade now... This isn't exactly "news"

      I think you're mistaken, "news" and "new" aren't the same thing. If you're pining for something "new" in this "news" it's the fact that they passed a significant milestone last week.

      Note: If English isn't your first language and you're mistaking "news" as the plural of "new" (which usually doesn't have a plural as it's not generally used as a noun) disregard.

    • Re: (Score:3, Insightful)

      by GameMaster ( 148118 )

      Yes, they've been working on VASIMIR, and many other technologies, for decades. What makes this story newsworthy is the fact that they've passed another major milestone and are one step away from real-world implementation in the space station. Unfortunately, public opinion often weighs heavily, whether we like it or not, on which technologies get the funding to continue development. This is true in government projects, like what NASA does, and doubly true in privately funded companies like the one develo

      • Don't get me wrong, I've been following VASIMR for a very long time, well over a decade now and I am very excited to see where it's headed. However, the title for the article is very misleading.

  • by Jawn98685 ( 687784 ) on Monday October 05, 2009 @02:09PM (#29647447)
    I've been building this big ol' rocket in my barn, here in Texas. If I could just get the feds off my back long enough to fuel the thing, I'd be happy to help out.
  • Perspective (Score:5, Informative)

    by LaminatorX ( 410794 ) <sabotage@prae[ ]tator.com ['can' in gap]> on Monday October 05, 2009 @02:10PM (#29647463) Homepage

    If you measure distance in terms of transit times, the sustainable thrust potential of this technology would make the Solar System the same size to travelers as the Earth was during the Age of Sail.

    • Re: (Score:3, Interesting)

      by petes_PoV ( 912422 )
      And maybe with the same level of risk (equipment failure / no hope of rescue, medical emergencies, solar storms, meteor strikes etc.). Although with our modern day aversion to risk, I can't see it getting a very enthusiastic welcome from todays "sailors". Not unless the rewards were very good indeed. Is there that much good stuff to be had to incentivise people to go?
      • by 4D6963 ( 933028 )

        Well one difference is what's at stake. Back then by being the first to get somewhere you could be the first to claim huge lands filled with potential slaves. In space, you can't claim a damn thing, and there isn't much to claim anyway. Even mining is nowhere near being economically viable.

        • Re: (Score:3, Insightful)

          by camperdave ( 969942 )
          Depends on what you're mining. A chunk of ice the size of Mt Everest could keep a spacecraft supplied with propellant, breatable atmosphere and water for many years. VASIMIR could tug one of those out of the asteroid belt and nudge it into orbit around Mars. Then when our brave and noble astronauts arrive, there'll be plenty of raw material for propellant and life support.
      • Re: (Score:3, Interesting)

        The simplest way to remove the problem of risk is to pay each person X million dollars upon arival back to Earth so long as they give up the right to sue for anythimg that can be traced back to the trip.
      • How can we incite people to use the already-existing word "incite" rather than making up words like "incentivise"?

      • Re: (Score:3, Insightful)

        by sexybomber ( 740588 )
        The rewards are, in fact, very good. As any self-respecting IT geek knows, one of the best ways to protect your data is through multiple, redundant, off-site backups. Homo sapiens currently has no such backups.

        Also, if you can physically get to an asteroid, that's the first step towards mining it, or perhaps nudging it (very, very carefully) towards Earth orbit, so as to mine it more easily.
      • The worldwide economy nearly collapsed due to ridiculously stupid real estate investment. Where is this "modern aversion to risk" that you speak of?

        People don't invest in space because there is little possibility of a return in their lifetimes. Stop pretending that prudence is cowardice. There is no shortage of dreamers willing to die in space on someone else's money.

      • Re:Perspective (Score:4, Insightful)

        by BarefootClown ( 267581 ) on Monday October 05, 2009 @03:51PM (#29648767) Homepage

        You're kidding, right?

        Right now, the chances of dying on a Space Shuttle trip are a bit over one percent. That said, I'll bet if you were to offer rides to the public--knowing full-well that the odds of dying in a fiery hell of hydrazine and liquid oxygen are about two in one-fifty--I'll bet the line would be around the block before the last words were out of your mouth.

        And I'd be at the front of that line.

        Do you really think there's any shortage of people who wouldn't love to go to space, to explore something new? Even without any reward--hell, even if you didn't pay a salary for their service--you'd have no trouble finding volunteers. Lined up around the block, probably more than a few fist-fighting for one space closer to the head of the line.

        And I'd make sure I won that fight.

        In fact, you could probably make it a one-way mission--we'll send you to Mars, you'll help us with experiments, and you'll plant a flag with your name at the base, but we can't bring you home--and the volunteers would come.

        Oh, yes, they'd come. Just for the chance to touch the soil of a foreign planet. The chance to travel to the great unknown, to be the first to do something truly majestic. Oh, yes, they'd come.

        • Re: (Score:3, Insightful)

          by camperdave ( 969942 )
          In fact, you could probably make it a one-way mission--we'll send you to Mars, you'll help us with experiments, and you'll plant a flag with your name at the base, but we can't bring you home--and the volunteers would come.

          I can't help but notice that you're not at the front of THAT line.
    • by yuriyg ( 926419 )
      In the Age of Sail there were tangible rewards like gold and spices. Unfortunately there aren't too many useful resources out there in space for us to use today.
    • Really? (Score:3, Informative)

      by Overzeetop ( 214511 )

      I was under the impression that VASMIR was a low-thrust technology (high energy, low propellant mass = high Isp, but normally with low absolute thrust). The proposed 200kW model was expected to have a thrust of 5 Newtons, according to wikipedia. Now, that's nice, but it's on the order of the smallest black powder Estes engines used to fly 50-100gram rockets for fun. It will move a space ship, but it will provide relatively low acceleration.

      Since sail circumnavigation of the earth can be done in less than 18

      • Re:Really? (Score:5, Informative)

        by LaminatorX ( 410794 ) <sabotage@prae[ ]tator.com ['can' in gap]> on Monday October 05, 2009 @03:27PM (#29648453) Homepage

        While 180 day circumnavigation is possible, the travelers of the 16th-18th Centuries usually took three to four years to circle the globe. That's the basis for the comparison I was making.

      • Yes Really! (Score:2, Interesting)

        by Anonymous Coward

        Mass of ISS = 3x10^5 Kg
        Diameter of Pluto's major orbital axis = 14x10^9m
        Thrust from a 200KW VASMIR engine = 5 newtons
        f=ma=5N so a=f/m=1/(3x10^5)= .333x10-5 = 3.33x10-6 m/sec^2
        s=1/2 at^2 so t=sqrt(2s/a)
        t=sqrt((28x10^9) / (3.33*10^-6)) = 1061 days

        So as anyone who completed high school physics can see even one of these engines can cross the entire solar system along Pluto's major axis in just under 3 years or about the amount of time it took Magellan's crew to circumnavigate the globe.

        This is a silly exam

    • If you measure distance in terms of transit times, the sustainable thrust potential of this technology would make the Solar System the same size to travelers as the Earth was during the Age of Sail.

      Assuming that somebody figures out how to power a VASMIR engine. The only power source Chang Diaz & Co. has to date is a black box on the diagram marked 'and magic happens here'.

    • Re: (Score:3, Informative)

      by joh ( 27088 )

      If you measure distance in terms of available air to breathe though it's still much larger.

      Really, two years or more in the Age of Sail was a very different thing. You could (and they frequently did) call to a port or some island to get supplies, breathing was free and there were much more options for ending the journey somewhat gracefully while for space travelers going back to Earth and getting safely back to the ground is the one and only option. Space is so much larger and emptier than even the oceans o

  • by ForexCoder ( 1208982 ) on Monday October 05, 2009 @02:12PM (#29647485)
    NASA really needs to move to a research and incubation role, similar to what it does in the aeronautical world. Given the constant changes in direction each new administration brings, and the whims of budgeting each new congress brings, NASA can't continue to be the primary source for launch vehicles.

    They should license out the Ares technology, promote competitions among the multiple private rocket vendors and focus on scientific and development missions using private vendors to provide the launch capacity.
    • Re: (Score:3, Insightful)

      That's exactly what they've been doing lately. SpaceX is in the process of becoming the primary provider of resupply missions to the ISS for when the shuttle program ends.
  • This is Huge (Score:5, Interesting)

    by hardburn ( 141468 ) <hardburn.wumpus-cave@net> on Monday October 05, 2009 @02:14PM (#29647505)

    VASIMR means the only expensive part is getting to LEO. Once there, a space tug using VASIMR can lift satellites to GEO for almost nothing (compared to today's prices). It's not really fast enough for human travel, but for moving equipment around Earth orbit (or elsewhere), it's very promising. Between this and SpaceX reducing the price to LEO, the next 10 years should be very exciting in commercial space travel.

    • The only problem with it being slow is that we live in a 'I want it NOW!!' culture.
      • by vlm ( 69642 )

        The only problem with it being slow is that we live in a 'I want it NOW!!' culture.

        Yeah, that and the van allen radiation belts. Not so bad if you scoot thru them quick, not so good if you slowly meander thru them. Kind of like taking the interstate thru the inner city at midnight, vs transiting the area on foot.

        • Actually those would not be a big problem. Since the 'engine' only has to go up once it can be equipped with the shielding required. The additional cost is then amortized over all the transits through the belt.
          • by vlm ( 69642 )

            Since the 'engine' only has to go up once

            I don't know about that... I'm talking about a tug-ship that would slowly spiral out, powered by a nice efficient vasmir, at least when its got direct sunlight. I think from your description you're wanting to haul a heavy tether up there one time using the vasmir? Personally I'd suggest trying one adventurous technology at a time, trying too many at once ruined the X-33...

      • by 32771 ( 906153 )

        The times they are a-changin:

        http://online.wsj.com/article/SB124385895294472035.html [wsj.com]

  • by alrudd1287 ( 1288914 ) on Monday October 05, 2009 @02:25PM (#29647665)
    Can't any amount of power move the ISS just at a slower rate?
    • Re: (Score:3, Funny)

      by orangesquid ( 79734 )

      (I'd imagine 200kW is needed for regular orbital corrections for the full ISS when all modules are in place, but I'm probably wrong. But here's something better:)
      No--because of NASA cuts, lawmakers have just ruled that physicists must add an additional ISS equation to quantum mechanics, governing the behavior of the ISS in orbit around Earth, so that quantization will inhibit orbital decay. They picked an equation where the only resonant energies were the only interesting orbits. Since the energies are q

      • by vlm ( 69642 )

        No--because of NASA cuts, lawmakers have just ruled that physicists must add an additional ISS equation to quantum mechanics, governing the behavior of the ISS in orbit around Earth, so that quantization will inhibit orbital decay. They picked an equation where the only resonant energies were the only interesting orbits. Since the energies are quantized, we can't just nudge the ISS a little bit at a time, now that it has its own wavefunction, duh!

        Rather than modifying formulae to add terms, wouldn't it be a heck of a lot simpler just to modify some minor coefficients that are part of the existing nuclear fusion equations to force the sun into a quiet state thus resulting in less atmospheric heating, thus less drag on the station? Of course the sunspots would go away... isn't that interesting?

    • by vlm ( 69642 ) on Monday October 05, 2009 @02:56PM (#29648079)

      Can't any amount of power move the ISS just at a slower rate?

      Kind of. It has to boost altitude, on average, more than 200 meters per day, just to keep up. Over and above that, yes anything will do.

      There is also a scheduling issue. Currently they burn chemical thrusters every month for a couple hours. That means no "microgravity environment" for less than 1% of the time. That is OK, 99% of the time is good enough for experiments, etc. Now, if the fancy new vasmir can only boost 400 meters per 24 hours of continuous operation, then just to keep up with atmospheric drag, it absolutely must run 1/2 of the time, meaning you only get that fancy microgravity environment for 1/2 of the time. Also with respect to maintenance and reliability, that means it has to be operational about half the time or better. And finally, a 1% of the time activity means direct astronaut operation/intervention is possible, but there is not the staffing to baby sit a low thrust engine literally half the time, so it has to be highly automated.

      http://web.archive.org/web/20080213164432/http://pdlprod3.hosc.msfc.nasa.gov/D-aboutiss/D6.html [archive.org]

      "Reboost mode is necessary because the Station's large cross-section and low altitude causes its orbit to decay due to atmospheric drag at an average rate of 0.2 km/day (0.1 n mi/day)."

      • by samkass ( 174571 ) on Monday October 05, 2009 @03:38PM (#29648611) Homepage Journal

        This may be a stupid question, but if there is no perceived gravity in a "perfect" orbit, but the ISS orbit is decaying, wouldn't that mean that the decay is being caused by acceleration, causing it to be less than a perfect microgravity environment. If you, on the other hand, had a tiny thruster operating 100% of the time that kept the ISS in its perfect orbit, wouldn't that mean a BETTER microgravity environment, not a worse one? In other words, by constantly counteracting the drag of the atmosphere instead of letting it build up then using significant thrust, wouldn't you go from microgravity 99% of the time to even better microgravity 100% of the time?

        • by vlm ( 69642 ) on Monday October 05, 2009 @03:55PM (#29648823)

          If you, on the other hand, had a tiny thruster operating 100% of the time that kept the ISS in its perfect orbit, wouldn't that mean a BETTER microgravity environment, not a worse one?

          In theory, yes, but in practice, good luck.

          Then you need 100% reliability or 100% redundancy. I would guess they'll require the engines to be shut off during spacewalks, maybe while the shuttle is docked (who knows what effect fumes could have on the tiles, etc). Conveniently you'll need multiple separate engine systems for reliability, so after the spacewalk you just light off both primary AND backup. True 100% operation and true 100% microgravity is unlikely.

          Not to mention whatever outgassing and optical effects the thrusters might have. If you only burn a chemical thruster 1% of the time every month or two, you can schedule optical and materials testing in the weeks up to a burn without interference.

          Finally you would need 100% power all the time, meaning pretty much nuclear is the only option. Either that or drain the batteries in the dark and charge them in the light, with a cycle every 1.5 hours. Icky. From an electrical standpoint, better off running the thruster only in the sunlight only on excess capacity after the batteries are topped off. I'm guessing that would be about a 10% duty cycle, about ten minutes every hour and a half, although it obviously depends on solar power available and to some extent on thrust required.

        • Re: (Score:3, Informative)

          It isn't a stupid question, and yes, by counteracting drag thrust can get you to true freefall.

  • Too many cooks... (Score:3, Interesting)

    by Last_Available_Usern ( 756093 ) on Monday October 05, 2009 @03:04PM (#29648155)
    Without oversight by NASA, components won't have the compatibility required to integrate within the launch vehicle. Essentially it means that all of these companies will just be contractors to NASA (Company X builds the fuel injection, Company Y builds the stage seperators, etc). Is that really cheaper than paying NASA employees to develop the same technology?
  • Anyone else disappointed in the 'video'. Nothing like some CGI and then some still photographs to NOT sate the urge to see a plasma engine in use.
  • Physics question (Score:5, Interesting)

    by gestalt_n_pepper ( 991155 ) on Monday October 05, 2009 @03:15PM (#29648305)

    Bank in 1999. electricity has been generated in space by dragging a copper tether though the earth's magnetic field (http://www.independent.co.uk/news/astronauts-seek-power-in-space-1319781.html).

    Presumably this produced drag. Can't this "drag" be used for some near earth maneuvering using a mesh system to create an electromagnetic sail by which one might tack? Or is the amount of force to small to be useful?

    • Ir can be done - in theory. In practice the engineering challenges to deploying and recovering a simple tether (let alone a much more complicated sail) are formidable, and no promising approaches have emerged to date.

    • You can't tack in a magnetic field. Well, you could, but it would require an actual change in the magnetic field. Remember, you can't make a net gain of energy in a closed system.

  • I liked the methane blast engine and its sound by XCOR Aerospace way more... http://science.nasa.gov/headlines/y2007/images/methaneblast/testfiring.wmv [nasa.gov]
  • Just how big of a rocket do you need to go from one movie studio lot to another?

  • The Electricity (Score:5, Interesting)

    by florescent_beige ( 608235 ) on Monday October 05, 2009 @03:40PM (#29648651) Journal

    Despite it's high specific impulse this engine isn't the whole answer to the exploration of the solar system. Blame the inverse square law.

    It may be feasible to power an slow unmanned Earth-Moon VASIMR transfer vehicle with solar, but at Mars solar radiation is only 25% as strong and at Jupiter it's 4%. So you are talking about nuclear for probes to the outer planets and for manned missions to anywhere.

    There's nothing technological that would stop space-based nuclear but you just know it'll take years to get that done.

    New Scientist [newscientist.com] has an article that says VASIMR + nuclear = 39-day transit time to Mars.

  • will it open a portal to hell like Carmack's space project?
  • What will revitalize NASA is for it to follow the law and get the hell out of the launch business like its supposed to.

    That will make way for the private sector to invest in launch services without fear of a "public option" driving their investors away at the critical moment.

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