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Miniprobes for interstellar exploration

  1. Nov 10, 2007 #1
    I know it would take an obscene amount of energy to put any type of manned spaceship within reach of neighboring stars... but why can't tiny probes, maybe the size of a baseball, or if necessary a marble, be sent instead? Say we explode a nuke to fling a few of these 'spaceballs' towards Proxima centauri... would the energy imparted be enough to get it there within a single human lifespan? If so, why isn't it being done?
  2. jcsd
  3. Nov 10, 2007 #2
    Maybe this should be in Astrophysics or regular physics, sorry
  4. Nov 10, 2007 #3
    because humans want to waste money and resources on flinging themselves into space- when it is completey unfeasable and impractical- probes and robots are the smartest way- and soon enough people will be able to either have a direct neural VR interface with robots and probes or even upload themesleves completely into them and explore space 'in person' without these silly notions of putting flesh and blood humans in space- the solar system and the stars belong to machines-
    Last edited: Nov 10, 2007
  5. Nov 10, 2007 #4


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    They will experience too high of a g-force if we fling them out with a nuke. To get data within the lifetimes of the engineers, 10% the speed of light or greater would need to be achieved. Accumulating all that velocity in the brief amount of time a nuke would deliver its energy would require a g-force greater than electronics can stand up to. I'm not even sure a nuke would provide enough focusable energy to achieve the necessary acceleration.

    Then there's the problem of a cramming a power source, a camera or other data-gathering device plus an antenna and transmitter capable of of delivering an acceptable amount data over a distance of over 4 light-years, into something the size of a baseball or marble.
  6. Nov 11, 2007 #5

    Chris Hillman

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    Most nations including the USA have signed treaties forbidding nuclear explosions in space. The US, UK, and USSR (now defunct) signed a treaty which came into force in 1967. IIRC, some "space-capable powers" not signed this treaty, so I guess you can try asking France.

    Explosions are not good ways to impart high velocities to anything you want to survive the explosion. Repeated nuclear explosions were infamously proposed in Project Orion but see preceding paragraph. The combination of chemical rocketry plus gravity assists (e.g. from passing Jupiter) remains the best known way of obtaining reasonably large (but nonrelativistic) velocities of space probes.

    Send smaller and cheaper but more numerous probes to cooperatively explore Europa, rather than complex orbiter-lander combo, have in fact been proposed.

    Robotic probes make sense; with current technology, manned space missions do not (except perhaps the kind of "space tourism for millionaires" pioneered by Rutan et al., which is silly but comparable to "extreme sports").
    Last edited: Nov 11, 2007
  7. Nov 11, 2007 #6
    Variant of Fermi's Paradox: Where are the self reproducing nano-tech devices that automatically build up entire civilizations when they land on planets? :smile:
  8. Nov 11, 2007 #7
    well if not nuclear , then how about a magnetic loop in space? Arent some theoretical physics tested by accelearting particles to relativistic speeds? Can we hypothetically build a space station enclosing a magnetic loop that can accelerate an object to close to the speed of light?
  9. Nov 12, 2007 #8
    The problem with "miniprobes" is that they're only a few magnitudes less difficult to send than full-scale missions, and it's difficult to imagine such a small package producing enough scientific merit to justify its funding in preference other projects.

    Exploration by VR is well and good until some disaster befalls the one basket in which all our eggs are still held..
  10. Nov 12, 2007 #9


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    Depends on what you mean, scalewise, by miniprobes. Technology places a lower limit on size. You need power for them to communicate with us and there are technological limits on how small the power sources and communication systems can be. You might, however, be surprised how small they already are.
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