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Space Travel n size of traveller

  1. Apr 20, 2005 #1
    What do u think?

    There is 3 category.

    1. Species which size bigger than us.
    2. Species which have the same size as us.
    3. Species which is smaller than us.

    Assuming all of the kinds have the same intelligence as us, living in different world, wish same earth like environment. Which one will be able to make space exploration faster? easier? Why?
  2. jcsd
  3. May 3, 2005 #2
    Perhaps i should change the question a bit.

    In most science fiction, the alien we encounter are always thought to be almost the same size or body like human.

    But if there really exist aliens, and one day we encounter them, use your imagination, what do you think they will look like??
  4. May 3, 2005 #3
    If they are on a planet such as Earth, gravity will be similar. They will not therefore be much larger than any Earth animal. Intelligent Brains need big energy sources, so slow moving large animals aren't really possible. So, human sized or smaller is my guess - it depends how efficiently nature can build an intelligent brain though.

    What will they look like? - impossible to guess.
  5. May 3, 2005 #4
    if they're smaller they can make smaller ships, and rely on less energy intake, i think??? also they will find it easier to leave their atmosphere, so the smaller the alien, the more likely that it will meet us first, but ultimatly, an alien could be just about whatever size that works for it and it's environment...
  6. May 3, 2005 #5
    If they were big, they would find it more efficient to jump to earth since they are so strong! Just adding to the bs...
  7. May 3, 2005 #6


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    I rather like the 1 micron long aliens that lived on the surface of a Neutron star in Baxter's SF book "Flux". Although there were a few details I didnt' like, on the overall I thought it was a very interesting idea. Also relevant would be Sturgeon's "The Mircocosmic God".
  8. May 4, 2005 #7
    i think i heard that there were aliens on the moon, alien bacteria off of a camera or something
  9. May 4, 2005 #8


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    There are practical limits to size and/or mass based upon both physics and physiology. The square/cube law prevents a 'solid' creature from getting too large and still being mobile in a non-supportive environment (ie: a blue whale, even if it had legs, wouldn't do well on land) There comes a point where the structural integrity of the body can't support the mass. Something gaseous, like an intelligent derigible, or sea-dwelling, could get a lot bigger. Likewise, if one sticks to any known neurological basis there is a lower limit to how small a brain can be and still have the capacity for intelligence.

    In that case, definitely check out 'Dragon's Egg' and the sequel 'Starquake' by Robert L. Forward. They're excellent accounts of life on a neutron star.
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