Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Transferal of life

  1. Aug 30, 2012 #1
    Signs point to life on Mars, billions of years ago, even before Earth..
    Is it possible that Asteroid impacts, launched rocks to Earth from Mars, and the bacteria in these rocks evolved on Earth? If so how likely is this scenario?
     
  2. jcsd
  3. Aug 30, 2012 #2
    IF evidence of life is
    found on Mars, and IF it shares similar bio-chemical properties, then the odds will be higher than what we can estimate today. For now, your idea falls in the realm of theoretically possible, and nothing more. Life could form anywhere and be blasted in to space by asteroid impacts. But until we see evidence for this, how can anyone say how likely it is?
     
  4. Aug 30, 2012 #3
    Well take into consideration, it is our closest neighbor.. There was a period of heavy bombardment. And the fact is, it would be impossible for the Earth not to contain thousands of LBS of Mars rocks.. And since Mars did have water, and if it had DNA based bacteria. It was transferred to Earth, because Mars would of had life before Earth did. And if we ever find DNA based life on Mars in a rock etc.. That would mean we are Martians..
     
  5. Aug 30, 2012 #4

    Chronos

    User Avatar
    Science Advisor
    Gold Member

    Why would you think martian life predated life on earth?
     
  6. Aug 30, 2012 #5

    Ryan_m_b

    User Avatar

    Staff: Mentor

    What makes you think abiogenesis on Mars was more likely to happen than on Earth? This question is entirely unanswerable at the moment. Firstly because we don't yet have a comprehensive theory of abiogenesis and secondly because our knowledge of martian history is so incomplete.
     
  7. Aug 30, 2012 #6
    Martian predators running wild :rofl:
     
  8. Aug 30, 2012 #7

    HallsofIvy

    User Avatar
    Staff Emeritus
    Science Advisor

    No, it isn't. Not counting the moon, Venus is our closest neighbor. Venus is about half as far from the earth as Mars.

    How does that follow?

     
  9. Aug 30, 2012 #8
    I have heard people refer to Mars in this way before. I think he meant "closest" as in most similar, and not physical distance. I also think people need to write more clearly to prevent misunderstanding! :-)
     
  10. Aug 30, 2012 #9

    Ryan_m_b

    User Avatar

    Staff: Mentor

    Is it though? I don't know the answer to that I'm genuinely curious.
     
  11. Aug 30, 2012 #10
    I don't know either. I was explaining a common alternative meaning of that phase in popular culture.

    Of the two neighbours, Mars and Venus, Mars would be my first bet for human habitation and for what we might recognise today as life. I will have to research if Venus today is similar to the climate of primordial Earth. In terms of colonisation, I don't know if I prefer Mars or the moon, but I will take either over Venus. Mars is further than Luna but water means greater potential for self-sufficiency.
     
  12. Aug 30, 2012 #11

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    In our solar system, probably, if mars really had an atmosphere and liquid water over significant timescales and if venus was not completely different before. Mercury is too close to the sun, all other planets are gas giants (and too far away from sun, so the moons do not help) and all minor planets are too small or way too far away from sun.
    In other planetary systems, there are planets more similar to earth than mars ;).
     
  13. Aug 30, 2012 #12
    There are actually small creatures called "Tardigrades" that are able to survive for extended periods of time in space, and some scientists think that this may be how life got on earth. There is a word for this theory, but I can't remember it...
     
  14. Aug 30, 2012 #13

    Ryan_m_b

    User Avatar

    Staff: Mentor

    I think you hit the nail on the head with popular culture. I'm always sceptical when people trump the colonise Mars idea. With a bit more water at the poles and a wisp of an atmosphere the Moon would be just as habitable. Bear in mind the Martian atmosphere is a small fraction of the pressure of Earth's and Mars has no biosphere at all for us to survive in. In fact we still don't have any real evidence to suggest how healthy land animals are if they are conceived, born and raised in low gravity let alone how well ecosystems would work.

    The whole habitability comparison seems to be like arguing whether it is more survivable to be shot in the face at point blank or blown up with a MOAB six feet away.
    Panspermia.
     
  15. Aug 30, 2012 #14
    Both Mars and Moon would need domes to live in.

    I believe the argument for Mars was:

    2H2O (drink) → 2H2 (fuel) + O2 (breathe)
     
  16. Aug 30, 2012 #15

    Ryan_m_b

    User Avatar

    Staff: Mentor

    Agreed, domes and closed ecosystems. Plus a large society to fill a specialised labour pool and a wealth of industries to support them...
    Pretty weak argument IMO.
     
  17. Aug 30, 2012 #16

    mfb

    User Avatar
    2016 Award

    Staff: Mentor

    You do not have to produce this from water, and you need the oxygen to burn hydrogen anyway. Both O2 + C <-> CO2 (food/breathing) and 2H2O <-> 2H2 + 22 (as energy storage) can be used as closed cycles.
     
  18. Aug 30, 2012 #17
    I'm not keen on either Mars or moon. Priority 1 has to be large asteroids approaching Earth.
     
  19. Aug 31, 2012 #18
    Couple questions..

    Is it true there are dried up river, deltas etc.. on Mars?

    Therefor there must of been water, IF there were single celled organisms that sprouted to life during this time, it is a FACT that they would be transferred to Earth during the Heavy Bombardment. Correct?

    This could very well be how life started off, since a lot of people think life came from amino acids from asteroids in the first place...

    Mars life (if true) would pre date Earth life, because around the time of the rivers on Mars, Earth was still in a cooling phase after the Mars size rock hit Earth, causing the Moon..
     
  20. Aug 31, 2012 #19

    Ryan_m_b

    User Avatar

    Staff: Mentor

    There are outflow channels on Mars but I'm not sure if it's definitive if they are caused by water.
    No. Just because there is water doesn't mean life arose. Even if life was there it's not a certainty it would be jettisoned off in a meteor. Even if it was jettisoned off there's no certaintly it would survive. And even if all that were true there's no certaintly that particular meteor would hit Earth.
    Who? The Miller-Urey revealed long ago that amino acids could have arisen on a primordial Earth.
    What sources do you have to support this?
     
  21. Aug 31, 2012 #20
    It appears "Mars == Nearest Neigbour" is no longer the domain of popular science. Look at the caption for the diagram at http://cars9.uchicago.edu/gsecars/LVP/publication/News/X-rays%20reveal%20secrets%20of%20Mars%27%20core.htm [Broken]

    I said in another thread that I am not surprised science journalists can't get it right when the source is ambiguous.
     
    Last edited by a moderator: May 6, 2017
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: Transferal of life
  1. Life on mars? (Replies: 14)

  2. Europa Life (Replies: 3)

  3. Life in the universe. (Replies: 91)

  4. Life on Venus? (Replies: 9)

  5. Life of stars? (Replies: 5)

Loading...