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Using Sling Shot Power to Hurl Into Orbit

Posted by CmdrTaco on from the still-wating-for-my-space-trebuchet dept.

the_2nd_coming writes "space.com has an article about a new application of a very old technology. NASA is putting money into Momentum-eXchange/Electrodynamic Reboost tether technology -- MXER for short -- an innovative concept that if implemented would station miles and miles of cart-wheeling cable in orbit around the Earth. Then, rotating like a giant sling, the cable would swoop down and pick up spacecraft in low orbits, then hurl them to higher orbits or even lob them onward to other planets."

13 of 310 comments (clear)

  1. Hmmmm by jeffkjo1 · · Score: 5, Funny

    Dennis the Mennis apparently grew up and got a job at NASA!

  2. hm... interesting possibilities... by Wakko+Warner · · Score: 5, Funny

    I once used sling shot power to hurl little rocks at my neighbor's cat. Used the middle finger from a rubber kitchen glove, a cut-apart 2-liter soda bottle, and a pipe clamp.

    If they built one of those in space, they'd be able to scare the shit out of my neighbor's cat.

    - A.P.

    --
    "Remember when the U.S. had a drug problem, and then we declared a War On Drugs, and now you can't buy drugs anymore?"
    1. Re:hm... interesting possibilities... by Tablizer · · Score: 5, Funny

      I once [made a] sling shot....Used the middle finger from a rubber kitchen glove

      Bet your mom was pissed that dish soap ruined her commute-finger.

      --
      Table-ized A.I.
  3. SciFi does it again by PaulK · · Score: 5, Insightful

    It seems that the greatest two motivators of technology are SciFi authors, and sales people.

    This approach was used by Robert Heinlein in several books; it is a pleasure to see his vision honored.

    As for sales people, I can't count the number of times that I have had to create what they have sold.

  4. Also by Anonymous Coward · · Score: 5, Funny

    When probes from outer space attack the earth, we can use the slingshot to go back in time to retrieve the exact species of whale they're trying to contact!

  5. With support of ACME Inc.? by OrangeGoo · · Score: 5, Funny

    Slingshots never worked out very well for the Coyote. Doesn't anyone pay attention to the great value of cartoons? Sheesh... how many boulders must fall on the heads of coyotes before someone gets it?

    On the other hand, rockets never worked for the Coyote either... maybe NASA is on to something! Is it possible... could cartoons be... unrealistic? Noooooo!

  6. Degrading Orbit by sublimusasterisk · · Score: 5, Insightful


    I noticed on one of the diagrams that the orbit of the slingshot itself degrades after each launch pick-up. Maybe the decrease in orbit isn't very significant, but would this system require self-adjustment? How would the system stay in service over the long term?

    --
    True believers seek redemption from the sin of death.
    1. Re:Degrading Orbit by foolish · · Score: 5, Interesting

      The tether system (more at www.tethers.com) decreases its potential energy after propelling the payload. Which is why they suggest a mix of tether technologies, one for the payload transport, and another electro-dyanamic propulsion. Brin wrote a story about the latter.

      What is kind of sad is that Dr. Robert Forward was one of the originators of the technology but he never got to see his work in space.

      Again, tethers.com explains it all much better than I can.

      --foolish

    2. Re:Degrading Orbit by Fjord · · Score: 5, Informative

      This thing is definitely cool. The other posters were right in pointing out that it regains the energy via converting solar energy into momentum by applying a current to the Earth's Magnetic field. I just wanted to point out the purpose of the devices name:

      Momentum-eXchange: this refers to how the tether adds momentum to the spacecraft

      Electrodynamic Reboost: this refers to the mechanism that recharges the orbit

      The one poster is right about the momentum-exchange working both ways in that spacecraft coming back could tether down and reboost the device. However, in most cases the craft will be leaving a payload up there (such as a satillite, or even just burned fuel/oxygen) so it would never regain as much momentum as it lost. The electrodynamic reboost ensure it keeps flying.

      --
      -no broken link
  7. Re:Fishnets!!! by overshoot · · Score: 5, Funny
    Say, if they make these smaller, maybe I won't have to keep buying pantyhose for my girlfriend!

    They last longer if you take them off first.

    --
    Lacking <sarcasm> tags, /. substitutes moderation as "Troll."
  8. Hurl into orbit? by Columbo · · Score: 5, Funny

    Gives new meaning to "Projectile Vomiting".

    Heh. Alright, I'll go away now.

  9. Obligatory... by Lane.exe · · Score: 5, Funny
    Meep meep.

    --
    IAALS.
  10. DON'T DO IT! by Xzzy · · Score: 5, Funny

    Don't these guys know anything about thermodynamics?!

    By launching a ship in this fashion, they will be STEALING momentum from the earth's rotation, degrading the planet's equilibrium and ultimately destroying the orbit and sending us to a firey death in the sun!

    This is obviously a "plan B" coming from those same wackos who want to send the moon crashing into earth by harnessing the energy in the tides.