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Space Technology

To Mars and Back in Ninety Days 812

paltemalte writes "A new means of propelling spacecraft being developed at the University of Washington could dramatically cut the time needed for astronauts to travel to and from Mars and could make humans a permanent fixture in space. In fact, with magnetized-beam plasma propulsion, or mag-beam, quick trips to distant parts of the solar system could become routine, said Robert Winglee, a UW Earth and space sciences professor who is leading the project."
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To Mars and Back in Ninety Days

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  • by Pig Hogger ( 10379 ) <pig.hogger @ g m a i l . com> on Friday October 15, 2004 @09:16AM (#10534316) Journal
    This is fine and well, but how does one meanwhile solves the most pressing problem, that is, providing CHEAP and RELIABLE means to get into earth orbit???
    • by EvilTwinSkippy ( 112490 ) <.yoda. .at. .etoyoc.com.> on Friday October 15, 2004 @09:26AM (#10534420) Homepage Journal
      Point taken. However, dropping the amount of fuel you have to hoist into orbit can only help.
    • by Rattencremesuppe ( 784075 ) on Friday October 15, 2004 @09:32AM (#10534493)
      With a space elevator, of course ;)
    • Getting to LEO (Score:4, Interesting)

      by WillWare ( 11935 ) on Friday October 15, 2004 @12:28PM (#10536362) Homepage Journal
      An earlier /. story about the space elevator got me thinking about this problem. My concern with the space elevator is that passengers spend a week in the Van Allen belts where there's a lot of radiation. On a couple of occasions I've discussed J. Storrs-Hall's space railway [imm.org] concept, but some have suggested it's less practical than the space elevator.

      So here's an idea. Put a captured asteroid into an elliptical orbit. Perigee is at about 200 miles, going about 10 km/sec, apogee is at about 18000 miles going about 1900 km/sec. As the asteroid approaches perigee, it lowers a cable (made of space-elevator rope) into the upper atmosphere. As the cable gets into the atmosphere, the asteroid starts paying it out very fast, so that the end moves slow enough to be grabbed by a high-altitude airplane and attached to a spaceship. Once attached, the asteroid pays out cable slower and slower, accelerating the spaceship to the asteroid's velocity, and very slightly slowing the asteroid in its orbit. Eventually the asteroid starts reeling in the cable faster and faster, accelerating the spaceship further.

      The spaceship only needs to be accelerated a little past the asteroid's velocity to reach escape velocity. There are a few possible ways to correct the energy loss of the asteroid's orbit. The simplest is for the airplane to attach a fuel tank to the cable along with the spaceship so that after the spaceship detaches, the asteroid can reel in the fuel and do a burn to pump its orbit back up.

      Of course there's a big PR battle to be fought, to make people feel good about a big rock in a relatively low orbit over the earth. But if it worked, it would use a lot less rope than the space elevator, and it would get you into space quicker.

  • Sign me up... (Score:5, Insightful)

    by Kick the Donkey ( 681009 ) <kickthedonkey.gmail@com> on Friday October 15, 2004 @09:16AM (#10534317) Homepage Journal
    Sign me up, should this ever become a reality. However, the only way space travel will become an everyday occrance is if it is profitable. Don't get me wrong. I'd love to do it for the sake of doing it. But people aren't willing to spend millions/billions/trillions of dollars to do something just because "its there".
    • Re:Sign me up... (Score:5, Insightful)

      by Tassach ( 137772 ) on Friday October 15, 2004 @09:24AM (#10534403)
      But people aren't willing to spend millions/billions/trillions of dollars to do something just because "its there".
      I would say that the tourism industry disproves that assumption quite nicely.
      • Re:Sign me up... (Score:3, Insightful)

        by danzona ( 779560 )
        I would say that the tourism industry disproves that assumption quite nicely.

        The tourism industry proves that people will pay money to send themselves someplace because "it's there".

        But the existence of the tourism industry is insufficient to prove that people will pay money to send someone else someplace because "it's there".
      • Re:Sign me up... (Score:3, Insightful)

        by Salgak1 ( 20136 )
        Except you'll need SOME sort of industrial base there already to support the hotels, the tourist traps, the passenger spaceports, the multi-lingual hookers, etc. . .
        Your idea only holds for a "cruise ship" type experience: see Jupiter and Saturn's Rings!
      • I would say the tourism industry, which was built because people are willing to spend millions/billions/trillions to go somewhere, disproves your statement quite nicely. Or did you forget that tourism is a for profit industry?
    • Need I remind you that the asteriods are rich with a host of rare metals that only exist in trace amount here on Earth. Indeed, one of the reasons mobile phones can't get any cheaper is that one part requires an obscenely expensive metal for the tuner.
      • Re:Sign me up... (Score:5, Insightful)

        by zarthrag ( 650912 ) on Friday October 15, 2004 @09:37AM (#10534534)
        I think I've said this before, but the nearest asteroid to earth is worth something over 3 trillion in materials.
        • Re:Sign me up... (Score:5, Insightful)

          by Tony Hoyle ( 11698 ) <tmh@nodomain.org> on Friday October 15, 2004 @09:49AM (#10534664) Homepage
          Actually it isn't... once we have the tech to get to the asteroids and farm them, the materials suddenly go from 'rare' to 'abundant', and the price drops faster than the space shuttle on reentry...

          This is precisely why DeBeers are so keen to differentiate between 'real' (ie. they dug them out of the ground and make a fortune out of) and 'fake' (manufactured, potentially dirt cheap) diamonds - even though you need an electron microscope to actually tell the difference.
          • Re:Sign me up... (Score:5, Informative)

            by tgd ( 2822 ) on Friday October 15, 2004 @10:59AM (#10535360)
            No, thats not actually why DeBeers is so keen to do that.

            Diamond is one of the most common gemstones in the world. It would have virtually no value if a) DeBeers hadn't pulled the greatest marketing spinjob in history convincing people today that diamond rings are a centuries old wedding tradition, not a decades old one and b) they didn't warehouse them.

            DeBeers has warehouses of bins, floor to ceiling of diamonds they keep off the market to artificially inflate their value. By controlling access to virtually all the mines that are econimical to exploit, they ensure competitors with access to diamond deposits will not flood the market with cheap ones.

    • Re:Sign me up... (Score:5, Insightful)

      by krunk7 ( 748055 ) on Friday October 15, 2004 @09:54AM (#10534720)
      Doing something "just because it's there" is exactly what has historically lead to the most profits:
      • The Americas
      • The moon (no profits you say? notice the tight correlation between our leap in technology and the lunar program?)
      • Every single instance of pure science that exists.

      Now the adventures and scientists always had a hook they sold to their Queen or benefactors.

      • "A path to Asia"
      • "Enhanced Missile design"
      • "Ermm, *cough* *cough* commercialization of space"
      The fact is, there is no predicting what fruits pure science will yeild, antibiotics, electricity, a new propulsion system, or different way of computing. The only guarantee is that if you throw enough money at them they will and it will pay off.

      The minute a nation forgets this fact and neglects the pure sciences in lieu of the sure thing, is the minute they begin to decline.

  • New Method? (Score:5, Insightful)

    by AKAImBatman ( 238306 ) * <akaimbatman.gmail@com> on Friday October 15, 2004 @09:16AM (#10534320) Homepage Journal
    What's all this about a "new method" being required for short trips to Mars? What about the 101 old methods [wikipedia.org] we have? Nuclear Thermal, Nuclear Electric, Orion, Laser Lifters, Nuclear Salt Water (this seriously needs to be developed!), Fission Fragment engines, Nuclear Steam ships, etc, etc, etc.

    We've got high powered propulsion options pouring out of our ears. It all comes down to getting funding. Wave a plan near congress and they're sure to kill it before breakfast.
    • by Professeur Shadoko ( 230027 ) on Friday October 15, 2004 @09:21AM (#10534370)
      You forgot the best:
      Press 'H' to jump into hyperspace.
    • Waving (Score:4, Interesting)

      by hummassa ( 157160 ) on Friday October 15, 2004 @09:22AM (#10534383) Homepage Journal
      Wave a plan near congress and they're sure to kill it before breakfast.

      Sure they will. The aliens don't want our crap in outer space at least until we can handle our problems like adult persons instead of reacting emotionally to every single difference between us. So, what's better than keep tabs in the govment of the only country that can fund such stuff?
    • Re:New Method? (Score:5, Informative)

      by pragma_x ( 644215 ) on Friday October 15, 2004 @10:05AM (#10534804) Journal
      Nuclear Salt Water (this seriously needs to be developed!)
      I had to look it up. Looks like a good candidate for in-space propulsion. If its as cheap as it is simple, then its definately worth looking into. I doubt it'll get the go-ahead for launchpad stuff... all that plutonium spewing out the back would freak people out.


      A nuclear salt-water rocket is a type of rocket designed by Robert Zubrin that would be fueled by water bearing dissolved salts of plutonium or U235. These would be stored in tanks that would prevent a critical mass from forming by some combination of geometry or neutron absorption. The rocket would be powered by a nuclear-thermal reaction when the water was injected into a reaction chamber.

      Calculations show that this rocket would have both very high thrust and a very high specific impulse, a rare combination of traits in the rocket world.
  • by Anonymous Coward on Friday October 15, 2004 @09:16AM (#10534324)
    You could build a rocket with a boiler that burned pieces of the ISS. At least *that* would be putting it to good use...
  • by denisbergeron ( 197036 ) <DenisBergeron@ya[ ].com ['hoo' in gap]> on Friday October 15, 2004 @09:16AM (#10534325)
    Oh! Sh!t we shoot the cabin insteed of the sail !
  • by Lumpy ( 12016 ) on Friday October 15, 2004 @09:18AM (#10534344) Homepage
    What are they looking at in creating particle or at least micrometeorite ablative shielding that can handle the increased velocity these hazards will bring with the increased speeds?

    right now our spacecraft are basically beer cans with insualtion and windows, any tiny object at any decent velocity can rip through them like tissue paper. on a long distance mission as a trip to mars would be, we need a craft that is at least 100 times stronger than anything we launch now which would make it more than that many times heavier.

    • by thorndt ( 814642 ) on Friday October 15, 2004 @09:28AM (#10534448)
      Speed is relative. Meteors (including micrometeors) often travel 100's of thousands of miles an hour w/respect to the EARTH. A measly 20-40 thousand mph difference in ship speed isn't going to make much difference to one of these bad boys.
    • by gl4ss ( 559668 ) on Friday October 15, 2004 @09:34AM (#10534504) Homepage Journal
      there's particles travelling high speed that might hit you, no matter what speed you're going yourself.
      and as such, high speed in this case wouldn't necessarely be 'increased risk'.

      if anything, it would be less risk of that(because the trip itself would take less time..).

      though, with this and the gazillion other "how to get to mars" plans there's holes in it that haven't been filled.
    • Not really. Micrometorites would be on the surface of the Earth. Now as for Micrometoriods... they are mainly a hazard to orbiting spacecraft, and mainly because mankind has been dumping stuff into orbit for 50 years. Sure, there are elevated risks of micrometeriod collisions around comets and such, but the little buggers are already moving at such a fantastic speed that the added velocity of the spacecraft is negligable.

      And no, spacecraft right now are NOT beer cans. They contain an outer shell, and several layers of different material to prevent micrometeriods from penetrating the pressure hull. Windows are specially designed, and if you pay attention to photographs from spacecraft you would see tons of scratches on the outer surface.

      Guess what they are from?

    • It's all about weight.

      The reason our spaceships are tin cans is because nobody can afford the weight for shielding. When 99+% of your mass is thrown away, carrying an extra kilo at the end means an extra hundred kilos at the start.

      But, if you have a good enough fuel that you only need 10 times your ultimate mass in fuel, suddenly you can carry shielding. The better your specific impulse (I_sp = pounds of thrust per pound of fuel used per second), the better your chances for shielding. An I_sp of 200 (a
      • Just a few nits - the Space Shuttle Main Engine has an Isp of ~430, and still throws away a lot of stuff! Most Hydrogen/Oxygen engines have Isp in the 400 range, while the 300 range is typically hydrocarbon such as kerosene. I would have difficulty believing that a 200 Isp engine would make it to orbit, if it hadn't already been done. (Pretty amazing engineering, that!) The mass ratio required goes up exponentially with Isp, and at 200 it is ~90:1 (so for every kg in orbit, you launched with 90 kg!).

        A
  • Phooey (Score:5, Funny)

    by geordie_loz ( 624942 ) on Friday October 15, 2004 @09:19AM (#10534347) Homepage
    I poo-poo your silly idea Philleas Fog.. It's impossible and I'll wager my reputation that you won't make it from the Gentleman's Club in London to Mars and back within 90 days!
  • by colmore ( 56499 ) on Friday October 15, 2004 @09:20AM (#10534362) Journal
    I hate to be a buzzkill, but is there ANY realistic reason why sending people to Mars is good science?

    It seems that if we spend the money that it would take to develop the spacecraft & lifesupport required to send people that far on better and more reliable robots, a lot more actual research would get done. Heck, we might even have enough left over to fix the Hubble.

    Let's work on practical reasons to send people into space at all... then maybe the moon. Billions of tax dollars shouldn't be blown on a project of little scientific validity just because "it's cool."
    • by josh3736 ( 745265 ) on Friday October 15, 2004 @09:27AM (#10534437) Homepage
      Billions of tax dollars shouldn't be blown on a project of little scientific validity just because "it's cool."

      I'm sorry sir, but you must now relinquish your Slashdot UID and turn in your geek card. Someone will escort you to the exit.

    • by Anonymous Coward on Friday October 15, 2004 @09:28AM (#10534451)
      ..is there ANY realistic reason why sending people to Mars is good science?

      No. There is no direct scientific reason to send humans to Mars. However there is a hell of a lot of capacity for new discoveries to be made and new technology to be invented by trying. Just look at the sort of stuff that came from the space program of the 50's and 60's. Likewise look at some of the stuff that came from [D]ARPA projects which on the surface had no direct scientific applications, but in retrospect gave us things like the Internet.

      Setting lofty goals and spending money on pure research and development without having to worry about practical application or reason is a great way to produce really good, useful science. Not mention it makes you look really good if you happen to be the nation doing it.
    • by Malc ( 1751 )
      It's a form of welfare. More socialist countries don't beat around the bush and hand out cheques. Socialism and welfare are taboo in the US, so it has to be done this way...
    • by b-baggins ( 610215 ) on Friday October 15, 2004 @10:48AM (#10535232) Journal
      And there lies a lot of the problem with the space program. It's become cold and lifeless. You sound like a freaking accountant except that instead of counting dollars, you're counting quanta of scientific data.

      We send people to Mars because it would be one glorious incredible acheivement of the human spirit and human will. We send people to Mars to hold our heads up high and say: Look what we can do, universe, now get out of our way.

      And some day, the wild horses of humanity will go into space, and all the domesticated men and women they leave behind will huddle around their pathetic lives and fade away into the gray mist reserved for all mediocrity.
  • Article Text (Score:4, Informative)

    by Anonymous Coward on Friday October 15, 2004 @09:20AM (#10534363)
    I barely got the page to load... here's the article text: A new means of propelling spacecraft being developed at the University of Washington could dramatically cut the time needed for astronauts to travel to and from Mars and could make humans a permanent fixture in space. In fact, with magnetized-beam plasma propulsion, or mag-beam, quick trips to distant parts of the solar system could become routine, said Robert Winglee, a UW Earth and space sciences professor who is leading the project. Currently, using conventional technology and adjusting for the orbits of both the Earth and Mars around the sun, it would take astronauts about 2.5 years to travel to Mars, conduct their scientific mission and return. "We're trying to get to Mars and back in 90 days," Winglee said. "Our philosophy is that, if it's going to take two-and-a-half years, the chances of a successful mission are pretty low." Mag-beam is one of 12 proposals that this month began receiving support from the National Aeronautics and Space Administration's Institute for Advanced Concepts. Each gets $75,000 for a six-month study to validate the concept and identify challenges in developing it. Projects that make it through that phase are eligible for as much as $400,000 more over two years. Under the mag-beam concept, a space-based station would generate a stream of magnetized ions that would interact with a magnetic sail on a spacecraft and propel it through the solar system at high speeds that increase with the size of the plasma beam. Winglee estimates that a control nozzle 32 meters wide would generate a plasma beam capable of propelling a spacecraft at 11.7 kilometers per second. That translates to more than 26,000 miles an hour or more than 625,000 miles a day. Mars is an average of 48 million miles from Earth, though the distance can vary greatly depending on where the two planets are in their orbits around the sun. At that distance, a spacecraft traveling 625,000 miles a day would take more than 76 days to get to the red planet. But Winglee is working on ways to devise even greater speeds so the round trip could be accomplished in three months. But to make such high speeds practical, another plasma unit must be stationed on a platform at the other end of the trip to apply brakes to the spacecraft. "Rather than a spacecraft having to carry these big powerful propulsion units, you can have much smaller payloads," he said. Winglee envisions units being placed around the solar system by missions already planned by NASA. One could be used as an integral part of a research mission to Jupiter, for instance, and then left in orbit there when the mission is completed. Units placed farther out in the solar system would use nuclear power to create the ionized plasma; those closer to the sun would be able to use electricity generated by solar panels. The mag-beam concept grew out of an earlier effort Winglee led to develop a system called mini-magnetospheric plasma propulsion. In that system, a plasma bubble would be created around a spacecraft and sail on the solar wind. The mag-beam concept removes reliance on the solar wind, replacing it with a plasma beam that can be controlled for strength and direction. A mag-beam test mission could be possible within five years if financial support remains consistent, he said. The project will be among the topics during the sixth annual NASA Advanced Concepts Institute meeting Tuesday and Wednesday at the Grand Hyatt Hotel in Seattle. The meeting is free and open to the public. Winglee acknowledges that it would take an initial investment of billions of dollars to place stations around the solar system. But once they are in place, their power sources should allow them to generate plasma indefinitely. The system ultimately would reduce spacecraft costs, since individual craft would no longer have to carry their own propulsion systems. They would get up to speed quickly with a strong push from a plasma station, then coast at high speed until they reach their destination, where they would be slowed by another plasma station. "This would facilitate a permanent human presence in space," Winglee said. "That's what we are trying to get to." Love, Tripptdf
    • Err.. thanks, but could you include paragraph breaks next time? :)

      The critical sentence:

      Under the mag-beam concept, a space-based station would generate a stream of magnetized ions that would interact with a magnetic sail on a spacecraft and propel it through the solar system at high speeds that increase with the size of the plasma beam.

      So this is a refinement of the laser/sail system proposed many years ago (and popularised by Niven & Pournelle's novel, The Mote in God's Eye).

      An interesting idea
  • by Xaroth ( 67516 ) on Friday October 15, 2004 @09:24AM (#10534404) Homepage
    The article mentions having one station here and another on the other side, so that the craft itself need not carry its own propulsion.

    However, any sort of malfunction - from the braking side not firing at the right time, to the braking side getting knocked off angle by a micrometeorite at the wrong moment, to the craft itself getting pushed off course - would mean that the craft itself would go hurtling through space with no real chance to be rescued.

    The way around this? Keep an on-board propulsion system that's able to slow it down from full-speed back to 0, and then speed it up enough to get back to where you were going originally in a reasonable amount of time.

    Which kind of defeats the purpose of the entire method.
    • by Control Group ( 105494 ) * on Friday October 15, 2004 @09:40AM (#10534574) Homepage
      This isn't really a problem.

      It sounds terrible, but really: any sort of malfunction in a self-contained craft, and the crew is completely SOL. This isn't like driving a car, where if you're off by a little bit, you just correct and pull into the correct stall anyway.

      All the equipment either works as planned and the ship stays on course, or it doesn't. If it doesn't, you're screwed. Period.

      But this is nothing new. Exploring new frontiers has always been dangerous, and that hasn't stopped people from doing it. Sailing across the Atlantic wasn't exactly safe; if something went wrong (including something like the wind not blowing), you were done. Travelling from the US east coast to the west coast wasn't exactly a joyride, either, as anyone who's played Oregon Trail can tell you.

      The point is, if we get ourselves hung up on making it perfectly safe, we'll never actually do it. Safety stagnates progress, because risk/reward is immutable. It's the unknown. That's both its value and its danger. What we need is a best-effort at safety, and willing volunteers.

      Something tells me that there'd be no shortage of the latter. Say someone walked up to you and said "you can be one of the first people on Mars...but there's a 10% chance you won't make it. Want to go?"

      It's possible you'd say no, I suppose. But there are plenty of people who'd leap at the chance, myself included.

    • Except that you are discounting the problem that a conventional propulsion system can also fail. Just because we've used it for 60 years doesn't mean it doesn't have problems. Puncture a fuel tank and a conventionally powered spacecraft would be equally screwed.

      At least with a malfunctioning beam projector you can repair it on station, have a spare station on standby, or try and capture the craft using an Earth based projector on the far side of Earth's orbit.

      If a conventional propulsion system fails on

  • Why dont we (Score:5, Funny)

    by Timesprout ( 579035 ) on Friday October 15, 2004 @09:26AM (#10534424)
    Just send a diplomat to Mars, establish a trade agreement and an alliance with them and build a road.

    Then we can quickly invade when they least expect it. When you play enough Rome Total War these things become soooo obvious.
  • For every action... (Score:4, Interesting)

    by jabber01 ( 225154 ) on Friday October 15, 2004 @09:33AM (#10534498)
    Has anyone gleaned from the article how the beaming stations are maintained in place?

    I got that nuclear and solar power would be used to generate the beam, but generating the beam would impart thrust to the station.

    Did I miss something?
  • Horse before cart (Score:4, Interesting)

    by James McP ( 3700 ) on Friday October 15, 2004 @09:33AM (#10534500)
    ..or at least the brakes. It's not a new plan, though it might be a new flavor. Nivens was talking about laser-based launching stations back in the 70s and he was just taking the most probable solution.

    Of course Newton's laws interest me. If you fire an energy beam able to move a 1000kg probe at 11.7km/s, your 10,000kg station is going to be moving 0.117km/s. (261mph)

    Then there's the power issue. Exactly what are these orbital launcher going to use for power? I don't see the green club letting enough fissionable materials get up there and otherwise we're looking at a biiiiig solar array tied to some form of energy storage (water/hydrogen/fuelcell?)
  • Second Law (Score:5, Insightful)

    by Wessler ( 204539 ) on Friday October 15, 2004 @09:36AM (#10534525)
    Can anyone tell me how the "pusher" satellite in the picture is supposed to work? I see one beam of energy with enough force to accelerate a spacecraft with a lot of force. Either there's an invisible other beam balancing this out, scorching the Earth underneath, or the satellite is doing a much better job of propelling itself out of the solar system than it is pushing the distant spacecraft where it's supposed to go. Or has someone figured out how to suspend Newton's second law?
    • by Quinn_Inuit ( 760445 ) <(Quinn_Inuit) (at) (yahoo.com)> on Friday October 15, 2004 @09:53AM (#10534704)
      Do not trust the pusher satellite. Pushing will protect you from the terrible secret of space. Do you have stairs at your house?
    • Re:Second Law (Score:3, Insightful)

      by Nagus ( 146351 )
      I haven't seen the article since it's slashdotted, but here I go anyway.

      You could first use the reaction force of the beam to make the pusher leave orbit (in a carefully calculated way). Later you point it at the spacecraft, and the reaction force will bring the pusher back into orbit. You just have to calculate the first firing of the beam such that the second firing will be in a direction that is useful for bringing the pusher back.

      Since the mass of the pusher will likely be bigger than the mass of the
  • by The Fun Guy ( 21791 ) on Friday October 15, 2004 @09:36AM (#10534530) Homepage Journal
    The big "breakthtrough" here is to decouple the propulsion system (the plasma beam) from the spacecraft. That makes the craft smaller and lighter since it doesn't have to move all that fuel around.

    HOWEVER...

    This system requires having another plasm beam generator to "catch" the spacecraft and slow it down with another plasma beam. That means not only sending the generator platform to Mars, but also all of the material from which to make the plasma (most likely nitrogen or one of the heavier noble gases). The generator platform needs a power source capable of sustaing the creating and acceleration of the plasma beam, which means nuclear, and a fission nuclear reaction, not radiothermic generation. All of that means a technically complex space station, with people to keep it running. To have such a system in Earth orbit would be tough enough. The cost and difficulty of shipping all of that material out to a Mars orbit, and maintaining it so it will be ready to deccelerate an incoming spacecraft would be Absolutely Enormous.
    • by Zarf ( 5735 ) on Friday October 15, 2004 @09:49AM (#10534665) Journal
      The cost and difficulty of shipping all of that material out to a Mars orbit, and maintaining it so it will be ready to deccelerate an incoming spacecraft would be Absolutely Enormous.

      The article appears slashdotted. But,
      Using this system means that you can't use conventional rockets and air-breaking to slow you vessel? Why can't the craft get a massive push from Earth orbit, then slow down using another form of propulsion once it gets to its destination?

      Granted it makes coming home a major pain. Now you have to come home the old fashioned way. But, getting there isn't so bad... and sending supplies out to outposts doesn't take too much either.

      The first few trips is to Mars in 45 days, to earth in 6 months. You can send all you want out to Mars or to meet a craft in transit in 45 days or less. Going home is a bigger problem.

      Think... boot strapping... start small... build up infrastructure. Eventually when enough infrastructure is built up at a remote location you can do Plasma Jets both ways.
  • by CFBMoo1 ( 157453 ) on Friday October 15, 2004 @09:55AM (#10534724) Homepage
    Scientists have come up with a cheap and reusable method of getting to orbit and traveling about the cosmose. Utilizing the effect of slashdotting a website, we beam those hits against a reflective matterial on the space craft that will allow network packets to propell it in to orbit and beyond. To slow down a craft ariving at it's destination, a special set of mirrors will be setup to redirect traffic to the front of the ship where another reflector will slow down the craft...

  • by mwood ( 25379 ) on Friday October 15, 2004 @10:11AM (#10534875)
    This reminds me of an idea from Larry Niven's Known Space stories. He thought that intrasystem transport would go through a phase in which photo-sail craft would receive an additional push from orbiting lasers sitting where they have access to high-density power supplies, making the light and simple vehicles fast enough to be practical for routine use.

    (This plan figured interestingly in the first Man-Kzin War. Kzinti planners had not used reaction drives in so long that they failed to realize what a fleet of exawatt laser stations scattered all over a star system could do to an incoming force. :-)

    Come to think of it, long-range focused plasma beams could have military uses, even if they aren't dense enough to instantly zap the other guy out of existence. So, funding should be assured. :-/
  • by Viol8 ( 599362 ) on Friday October 15, 2004 @10:14AM (#10534907) Homepage
    Otherwise there won't be any slowing down at Mars , just a big splat. Unless the ship carries conventional thrusters too of course, but the fuel required to slow down would be immense and then we're back to square one.
  • by tod_miller ( 792541 ) on Friday October 15, 2004 @10:34AM (#10535102) Journal
    Imagine when 80 days around the world was an extraordinary and unbelievable accomplishment, now it seems that something as odd as 80 days around the solar system may be laughed at in a 100 years time.

    In todays world, I cannot imagine how restrictive travel must have been, in tomorrows, they will pity us with our cars and segways!
  • by museumpeace ( 735109 ) on Friday October 15, 2004 @11:50AM (#10535883) Journal
    NASA has this page [nasa.gov] explaining the physics and why it granted the money to the UWash research team. And the NASA page responds...The UWASH page pointed to by the article is somewhere behind a cloud of smoke coming out of their poor slashdotted server. 350 comments later, I still cant raise it.
  • by GuyFawkes ( 729054 ) on Friday October 15, 2004 @11:55AM (#10535942) Homepage Journal

    I'm an engineer.

    If you put me in charge of a Mars mission here's the only proper way to do it.

    #1 what we did in the sixties, whistle stop one pass visits, are pointless, if you're going to go then go, don't fuck around.

    #2 we have the perfect platform for solar system operations right on uor doorstep, Luna, that and the L1 and L2 largrange points in lunar orbit for stuff that the moon's 1/6th gravity will make difficult or expensive.

    #3 all space vehicles will need enough delta vee to decelerate to matching velocity with the target, whether that target is Mars, another planet, or an asteroid, that's no big deal we can use MHD which will efficiently generate low braking thrust for long periods.

    #4 all space vehicles and this includes "materiel" of any kind, including "lego" style construction sets and so on, can be given practically any velocity you like by launching from a lunar linear accelerator, these work REALLY well in a vacuum.

    SO top priority will be getting mebbe 500,000 tons of mass up to the moon to buind a nearly self sufficient base.

    Best way to do that is a two pronged approach.

    1/ Develop REALLY heavy lifters, nuclear salt water is cool as a starting point, first step need to be throw everything at perfecting Fusion until it's as doable as fission power plants.

    2/ Develop (materials) for the space elevator.

    The united states spends 450 BILLION dollars every year on the military, if that lot was thrown at this project you could adopt a JFK / Apollo sort of timescale and we'd have a viable and working moonbase by 2020 AD easy.

    If the USA doesn't do this, there will be a moonbase by 2050 at the latest, and it will be Chinese.

    When that happens the entire might of every military on the planet, IN CONJUNCTION, will be as effective as wet toilet paper agauinst a .50 cal browning against a lunar linear accelerator with unlimited megatons of purely ballistic projectiles that could be fired as fast as you could fill the accelerator loader.

    Who knows, I may even live long enough to see it.
  • by radiumsoup ( 741987 ) on Friday October 15, 2004 @01:55PM (#10537531)
    I am ignorant of the forces used in this technology, but if I am correct...

    You have a space plasma generator orbiting the sun that will push payloads into a Mars-intercepting trajectory. OK, fine and dandy.

    Now, if it's shooting all this high energy plasma out one end, won't there be a reaction of its own in the opposite direction, effectively causing the force on the payload to be cut in half, while also shooting itslef way the heck out of the original "stationary" orbit? I'm sure someone smarter than me has already thought of this, I just can't see the solution.

The biggest difference between time and space is that you can't reuse time. -- Merrick Furst

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