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NASA Tests New Moon Engine

Posted by Soulskill on from the rocket-fuel-green-cheese-hybrid dept.

Iddo Genuth writes "Pratt & Whitney Rocketdyne of West Palm Beach, Florida has successfully completed the third round of its Common Extensible Cryogenic Engine (CECE) testing for the National Aeronautics and Space Administration (NASA). CECE is a new deep throttling engine designed to reduce thrust and allow a spacecraft to land gently on the moon, Mars, or some other non-terrestrial surface." NASA is also set to launch a new satellite on Tuesday — the Orbital Carbon Observatory — that will monitor the level of carbon dioxide in the atmosphere. On the research front, NASA has announced this year's Centennial Challenges. $2 million in prizes are available for a major breakthrough in tether strength (one of the major obstacles for developing a space elevator), and another $2 million is being offered to competitors who are able to beam power to a device climbing a cable at a height of up to one kilometer.

11 of 75 comments (clear)

  1. Space elevator power? by CRCulver · · Score: 4, Insightful

    Another $2 million is being offered to competitors who are able to beam power to a device climbing a cable at a height of up to one kilometer.

    Wouldn't it just make more sense to have solar panels in orbit and transmit the power along the space elevator? If I remember correctly, this is what Kim Stanley Robinson envisioned with the space elevator in his science fiction novel Red Mars . Being able to bring power down would be a nice bonus for a tool to get up to orbit easily.

    1. Re:Space elevator power? by John+Hasler · · Score: 2, Informative

      It's the same problem whether you are sending the power for the climber up from below or down from above.

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      Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
    2. Re:Space elevator power? by khallow · · Score: 3, Insightful

      Why should it make more sense to not bother? Even if a space tether from Earth proves to be too difficult to bother with this century, we currently have the materials to make less ambitious tether strutures in orbit or a space elevator on the Moon.

    3. Re:Space elevator power? by Kleen13 · · Score: 2, Insightful

      And you are? What if he owned a hardware store? Would that count?

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    4. Re:Space elevator power? by ThreeGigs · · Score: 2, Interesting

      Actually, it makes the most sense (to me) not to use a powered 'climber' at all.

      If the space elevator is ever deployed, instead of dropping a single tether down to Earth, they should drop a LOOP. Run the bottom of the loop around a pulley on Earth, and the top through a pulley on the counterweight in space. Add a motor to the pulley on Earth and you've got one half constantly going up, and the other half constantly going down.

      All a 'climber' would then have to do is clamp onto the cable and allow itself to be pulled up, and unclamp at the appropriate time in space. So... no need for motors on the 'climber', no need for an energy receiver on the climber, no need for beam generators anywhere. Essentially turning the "Space Elevator" into the "Space Ski Lift".

      The only engineering challenge I can think of would be preventing the up-going side from touching, or coming too near the down-going side. Potentially solved with two pulleys each on the ground and in space, each pair a kilometer or more apart so the 'tether' goes down, across, and then back up.

    5. Re:Space elevator power? by TropicalCoder · · Score: 3, Informative

      I think one of the silliest notions I ever heard is the idea that we could propel a carriage without a horse, by using explosions from a highly explosive liquid substance. Obviously the first time they try this they are just going to blow the carriage sky heigh. The simple reason this will never work is that they forgot that a carriage has a thing called inertia, and it will quickly buckle under the force of the explosions rather than be propelled down the lane. Even if it could withstand the force of the explosions, could you imagine what kind of jerky ride you would have?

    6. Re:Space elevator power? by camperdave · · Score: 2, Informative

      Doesn't the moon's slow rotation prohibit a space elevator?

      Yes and no. Yes, by itself the moon's slow rotation would call for a really long tether (to match the 27.3 day rotational period, and the counterweight would be too strongly influenced by Earth's gravity. I haven't done the calculations, but it wouldn't surprise me if the tether would have to pass through the Earth itself.

      However, there is another space elevator design that will work. Between the Earth and the Moon lies the first Lagrange point of the Earth-Moon system (EML1). It is essentially the point where the gravitational pull from the Earth matches the gravitational pull of the Moon. Anything on the Earthward side of the EML1 gets pulled to the Earth, and anything on the Moonward side of EML1 gets pulled to the Moon. So, basically what you do is hang the counterweight on the Earthward side of EML1, and run the tether to the Moon. The counterweight is going to want to fall to Earth, but it will not be able to because it is tethered to the Moon.

      Apparently we have sufficiently strong materials right now to be able to create such a tether. There are still engineering difficulties (such as getting a 56,000+ km length of kevlar rope strung out from the moon to the counterweight) but a lunar tether lies within our current technological capabilites

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    7. Re:Space elevator power? by robthebloke · · Score: 2, Insightful

      A large metal wire cutting through the earths magnetic field is all you need to generate electricity (ask anyone who plays the electric guitar). All you need to do is find a way to harness the current that would be generated in the space elevator cable.

      If you attempted to stick a current through the elevator cable, my primitive understanding of physics says, oscillations will start to occur in the cable due to the way magnetism and electricity are related?

  2. A what? by Anonymous Coward · · Score: 2, Funny

    CECE is a new deep throttling engine

    Took me a second look to realize that I'd read it wrong the first time...

  3. ust not bother???? by spineboy · · Score: 2, Insightful

    Why then try to do anything? Artificial light, nuclear power, cars, organ transplants? They were all impractical at first.

    If this was a rhetorical question, then I lost and bit, but otherwise, with this attitude, not much would have ever been invented or tried.

    The space elevator might be the best and most efficient way to get large amounts of material into space, unless we invent anti-gravity.

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    ..........FULL STOP.
  4. New? They had these in 1936! by Richard+Kirk · · Score: 2, Informative

    See... http://www.luft46.com/misc/sanger.html Note the engine details. There is a jet engine fuelled by liquid oxygen and hydrogen, piped through the jet bell, so it gets cooled and the fuel gets vapourized. Neat, eh? Clever guys, those Germans.