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Mars Science

VASIMR Ion Engine Could Cut Mars Trip To 39 Days 356

An anonymous reader writes "It would take about 39 days to reach Mars, compared to six months by conventional rocket power. 'This engine is in fact going to be tested on the International Space Station, launched about 2013,' astronaut Chris Hadfield said. The Variable Specific Impulse Magnetoplasma Rocket (VASIMR®) system encompasses three linked magnetic cells. The 'Plasma Source' cell involves the main injection of neutral gas (typically hydrogen, or other light gases) to be turned into plasma and the ionization subsystem. The 'RF Booster' cell acts as an amplifier to further energize the plasma to the desired temperature using electromagnetic waves. The 'Magnetic Nozzle' cell converts the energy of the plasma into directed motion and ultimately useful thrust."
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VASIMR Ion Engine Could Cut Mars Trip To 39 Days

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  • I'm dizzy. (Score:1, Interesting)

    by garcia ( 6573 ) on Monday October 19, 2009 @10:21AM (#29793791)

    From the article:

    A new NASA rocket engine, designed partly in Canada, raises the revolutionary possibility that a manned trip to Mars could take less than three months instead of two years.


    It would take about 39 days to reach Mars, compared to six months by conventional rocket power.

    In three paragraphs we go from 89 days to 39 days. So which is it? With that kind of difference, I'm not quite sure it would be any faster than conventional rockets.

  • by dkleinsc ( 563838 ) on Monday October 19, 2009 @10:22AM (#29793803) Homepage

    Yeah, coverage like this really makes we want to go out and buy one for my own space ship.

    Seriously, I think this might be getting coverage because this is potentially technology that could make a manned mission to MARS much more feasible and safer. Of course, getting back might still be challenging, but I for one would take the honor of being the first man on Mars away from Philip Fry if I could.

  • by Anonymous Coward on Monday October 19, 2009 @10:29AM (#29793897)

    Mind you to obtain this 39 day route, you're not going to be doing it by feeding the VASIMR's klystrons off solar cells stuck to the outside of the ship. That's more of a one year sort of trip.

    If you want the 39 days, you're going to need to pump the voltage in with a classic onboard nuclear reactor. Not to worry though, both the US and Russians made and tested (The Russians flew) several dozen types of space borne fission reactors in the 60s-80s so this is no great leap. Other than perhaps getting the eco-hippies to shut up about lofting lots of highly enriched nuclear fuel.

  • by John Hasler ( 414242 ) on Monday October 19, 2009 @10:32AM (#29793939) Homepage

    All rockets are "impulse engines".

  • by Anonymous Coward on Monday October 19, 2009 @10:36AM (#29794011)

    LOL, if it can push a rather large ship out of Earth's orbit, it can keep the ISS in orbit. The one that is being sent up is rather on the small side though. There was mention in one of the articles about it recently that it could be used for station keeping however.

    Bear in mind that it requires a power source for all the energy expended in heating and controlling that plasma, shich in this instance would have to come frrom the station's solar panels. That kind of energy draw was never considered in the original design.

  • by JSBiff ( 87824 ) on Monday October 19, 2009 @10:36AM (#29794013) Journal

    So, it appears that the VASIMR page shows a diagram where an external power source is applied to the engine (I presume in the form of electricity). Are there any electrical generators currently in existence which would be suitably compact and low enough mass, while at the same time generating sufficient power, to actually power this thing (basic physics tells me that no matter what propulsion method you use, energy is energy, and it takes a LOT of energy to generate large accellerations)? Or is this engine gonna have to sit on the shelf after being developed, while we figure out how to power it?

    I suspect this thing would need some sort of small/light power generator that can produce a GW or more of power. So, do we need to first perfect fusion power before we can actually use this engine?

  • Re:Sound (Score:5, Interesting)

    by isaac ( 2852 ) on Monday October 19, 2009 @11:00AM (#29794373)

    But does this process create feedback over communications systems to create cool sound effects as the ship whooshes by?

    Quite possibly, actually; at the very least, there might be enough radio emissions at audible frequencies as the plasma dissipates in the presence of a magnetic field (i.e. planetary orbit) to induce something audible in a speaker wire or analog amplifier. It's been speculated that such a mechanism is responsible for the phenomena of hissing, whooshing, or popping sounds heard simultaneously with the appearance of meteorites passing through the atmosphere (as opposed to delayed like a sonic boom.)


  • Re:Sound (Score:2, Interesting)

    by mlush ( 620447 ) on Monday October 19, 2009 @11:30AM (#29794745)
    I've always assumed the whoosh was synthesized by the ships systems as a audio representation of the local battlespace
  • Re:No quite yet. (Score:5, Interesting)

    by jollyreaper ( 513215 ) on Monday October 19, 2009 @11:46AM (#29794949)

    In theory, you could use a small glass of water, accelerated to a significant fraction of the speed of light, as your propellant for an entire trip to Mars and back. In practice, there is a limit to the speed to which an ion thruster can accelerate the ions it's throwing out and so you still need quite a large amount of propellant.

    And also led to the scifi observation (niven or pournelle, I forget which) that any technology that makes for a decent spaceship engine also makes for a decent weapon.

  • by bds1986 ( 1268378 ) on Monday October 19, 2009 @11:51AM (#29795007)

    If something goes wrong on the surface, help is 39 days away, instead of 6 months.

  • Re:No quite yet. (Score:4, Interesting)

    by CopaceticOpus ( 965603 ) on Monday October 19, 2009 @11:51AM (#29795009)

    The VASIMR engine couples well with an idea I've been pondering. Imagine building a ship designed to latch onto a largish asteroid, and then use the asteroid's mass as the ejected reaction mass for acceleration.

    The ship would need a powerful nuclear reactor, and robotics capable of slowly grinding the asteroid's mass to a fine powder. The engine would need to be able to accelerate this powder to an enormous speed, regardless of what the powder was made of.

    Such a ship would be able to accelerate to amazing speeds, and could be a perfect deep space explorer. Imagine if we could do a close flyby on another solar system! The powerful nuclear reactor could be used to power advanced scientific instruments, and to beam a very strong signal back to earth.

    I wonder how feasible this would be. I'd love to see an unmanned craft reach another solar system in my lifetime. To me, that would be more exciting than putting a man on Mars.

  • Light speed probes (Score:3, Interesting)

    by GodfatherofSoul ( 174979 ) on Monday October 19, 2009 @11:57AM (#29795079)
    I'd like to see a test probe fly just as fast as we can get it to go. I'm sure it'll be pulverized by dust motes if you can get it moving fast enough, but it would be cool to see something we've created jetting about a some considerable fraction of light speed. Maybe you can get to another star system in a human lifetime?
  • by avandesande ( 143899 ) on Monday October 19, 2009 @11:59AM (#29795119) Journal

    The logical thing to do would be to get the return vehicle in orbit around mars, ready to go before an astronaut leaves earth. This would be make reduce the number of errors that would put an astronaut into a life threatening situation (return failure).

    A relatively small rocket could be used to get the astronaut off of Mars' surface. It won't take much with its lower gravity and thin atmosphere. We could even test all these scenarios remotely.

  • Re:No quite yet. (Score:3, Interesting)

    by drinkmorejava ( 909433 ) on Monday October 19, 2009 @12:00PM (#29795129)
    Actually, conventional rockets are not limited by the rate of reaction. Momentum is limited by the density of the gas and the cross sectional area at the throat of the nozzle where the flow hits the sonic condition. You could speed up the reaction a million times and increase the pressure in the reaction chamber as much as you wanted, but the flow will absolutely not go any faster than Mach 1 at the throat, period. ...Just saying. And yes, I am a rocket scientist.
  • Re:No quite yet. (Score:4, Interesting)

    by EvilTwinSkippy ( 112490 ) <[yoda] [at] [etoyoc.com]> on Monday October 19, 2009 @12:01PM (#29795151) Homepage Journal
    Nuclear reactors don't have to be all that heavy. The Pioneer and Voyager spacecraft had plutonium power cells. You pretty much can scale nuclear power to whatever size and power you need. (We don't usually use small power plants simply because it's more cost effective to power devices other ways.)
  • by WindBourne ( 631190 ) on Monday October 19, 2009 @12:18PM (#29795439) Journal
    First, it is easy to send up lots of uranium into space. It can be sent in capsules that can take any issue (heat, water, etc). BUT, the simple fact is, that the moon has been found to contain Uranium. And it appears to be a LOT. It should be possible to mine it and send it various places. While I was actually a fan of Mars first, now I back the moon due to the water and uranium. Combine that with an electric launcher and it should be possible to send missions at extremely fast rates through the solar system.
  • Re:No quite yet. (Score:4, Interesting)

    by mmontour ( 2208 ) <mail@mmontour.net> on Monday October 19, 2009 @02:47PM (#29797727)

    There's a bit of a confusion of terms here - nuclear reactors do have some degree of a size restriction, but neither the Pioneer or Voyager programs used nuclear reactors as their power source.

    The Soviet Cosmos [wikipedia.org] satellites used true nuclear reactors.

  • Ready to Colonize! (Score:1, Interesting)

    by Anonymous Coward on Monday October 19, 2009 @04:33PM (#29799627)

    39 days!
    Colonization is very doable with only a month...the Europeans took longer to get to N. America by sail (or Polynesians going east to Hawaii).
    Fast enough that it may be possible to go out even on non-ideal planetary alignments.
    One could send out plants and basing stuff right off the bat and follow with ship 2 with supplies and more permanent base-making stuff.
    One could also set up a base in Mars orbit to refuel multiple ships to mine asteroids :0)

  • Re:No quite yet. (Score:3, Interesting)

    by cheesybagel ( 670288 ) on Monday October 19, 2009 @05:30PM (#29800435)
    Nuclear reactors for electric propulsion in near Earth space are not nearly as useful as claimed... You need to dissipate a lot of thermal energy from the reactor using radiative dissipation. The dissipation panels end up being so large and heavy you were probably better off using the solar panels in the first place.

    Once you get away from Mars though, they start to make sense.

"No, no, I don't mind being called the smartest man in the world. I just wish it wasn't this one." -- Adrian Veidt/Ozymandias, WATCHMEN