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A Mars as Second Earth

  1. Apr 19, 2016 #1
    I have been reading about Mars and planetary rotation and gravity. It seems to me Mars was in Earth's rotation at one time. Most likely it's first period. I want it back. I don't believe it's an impossible task. People exercise drilling and fracking and sending out satalites. How impossible is slowing down Mars orbit so it'll fall into ours using these methods? We only need to slow it about 4 light minutes.
     
  2. jcsd
  3. Apr 19, 2016 #2
    Reposted under astrology
     
  4. Apr 19, 2016 #3

    Drakkith

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    It is extremely unlikely that Mars was ever in the same orbit as Earth.

    The amount of energy needed to move a planet into another orbit is staggeringly huge. More than the total sum we've ever used here on Earth. It would take about 1.8x1032 J of energy to move Mars into Earth's orbit. By comparison, humanity used about 5.67x1020 J of energy in 2014. That a difference of about 12 orders of magnitude. At that rate of energy use, it would take about 100 times the current age of the universe to use 1032 joules of energy.
     
  5. Apr 19, 2016 #4

    Drakkith

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    We don't have an Astrology forum. :wink:
     
  6. Apr 19, 2016 #5
    The only things powerful enough to move planets, is another planet.

    Also, once it was in our orbit, what would you do with it? You can't have two planets in the same orbit.
     
  7. Apr 19, 2016 #6
    Um, you can. Earth has less than 1/27 the mass of Sun.
    Would you want Mars to be a Trojan or an Achaean?
     
  8. Apr 19, 2016 #7
    Dragging an asteroid and having a planet there seem to me like they're different sorts of things. Mars has millions of times the mass of a trojan asteroid. I'm quite certain the gravitational attraction between the two objects would cause them to drift towards each other and go into chaotic orbits.
     
  9. Apr 19, 2016 #8

    Chronos

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    Moving mars, however implausible it may seem, would not remedy its habitability issues. Moving it closer to the sun would exacerbate the effects of the solar wind making it even more difficult to teraform. Without a significant magnetic shield it would be defenseless and giving it one would make relocating mars appear trivial by comparison. Like space travel, planetary engineering is immensely energy intensive. It's not just a matter of resources, we can't even imagine what might provide a sufficient energy source, much less how to harness it.
     
  10. Apr 19, 2016 #9

    Janus

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    One of the major factors determining the stability of a Trojan object is the mass ration between the planet and the Sun. Since the Sun is some 330,000 times more massive than the Earth, this allows a bit of leeway for the mass of the Trojan object. To text the idea as to whether Mars would be stable at as an Earth Trojan object, a ran a grav-sim simulation. Since perturbations from other bodies can effect the stability I added a Jupiter to the Simulation. after 15,000 simulator years, Mars still showed no signs of changing its relative position with respect to the Earth.
     
  11. Apr 19, 2016 #10
     
  12. Apr 19, 2016 #11
    newjerseyrunner, Thank you for your response. No. You are right. Another massive satellite to earth would drag on Earth to do all sorts of wrong things. And there is no way to ensure Mars could orbit at same speed as Earth peacefully at the 180 of Earth. I think making Earth 2 (E2) would require moving Mars closer to the sun though. What I would do with it is let it self regulate ( terraform ) for many years. And then populate it. See other replies coming to below responses. Isn't it fun speculating tho![/QUOTE]
     
  13. Apr 19, 2016 #12
    It is extremely unlikely that Mars was ever in the same orbit as Earth.

    It is unlikely that Mars has been in its current position since its formation. Maybe its magnet field fell after it was knocked out of its original position. Maybe its was in the same orbit but it was tramatically 're-positioned' during its polar flip, thus not being able to recover the magnetic dynamo? Perhaps the moving of Mars would place enough stress to the core it already has to reform the magnetic shield?

    Also I just found this so my uneducated opinion is being validated out there. :) https://www.newscientist.com/article/dn20160-two-planets-found-sharing-one-orbit/

    The amount of energy needed to move a planet into another orbit is staggeringly huge. More than the total sum we've ever used here on Earth. It would take about 1.8x1032 J of energy to move Mars into Earth's orbit. By comparison, humanity used about 5.67x1020 J of energy in 2014. That a difference of about 12 orders of magnitude. At that rate of energy use, it would take about 100 times the current age of the universe to use 1032 joules of energy.[/QUOTE]

    We would need 'smart guy' to figure out how to use the solar system's (ss) elements to act as a pulley. I know we are no where near to harnessing the ss energy much less how to direct that energy. But I think to terraform a dying planet is less sci-fi than traveling to a ready made planet.

    Thank you for your reply.
     
    Last edited: Apr 19, 2016
  14. Apr 19, 2016 #13
    Also I just found this: https://www.newscientist.com/article/dn20160-two-planets-found-sharing-one-orbit/
     
  15. Apr 19, 2016 #14
     
  16. Apr 19, 2016 #15
    I
    I can't answer that yet. I get the Trojan asteroid reference but I haven't read up on Achaean yet. I'll try to reply tomorrow....that was easy reading. Achaean. Two planets in one orbit forming at the same rate yet one with a slight difference in velocity so that in 500 million years or so the smaller less protected planet got ever so gently pushed away.
     
    Last edited: Apr 20, 2016
  17. Apr 20, 2016 #16
     
  18. Apr 20, 2016 #17

    Drakkith

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    I loaded up my Universe Sandbox (find it on Steam), loaded up the Solar System, and put Mars a little ways behind Earth and in a very similar orbit. After 1100 years there's no sign of any obvious drift.

    Indeed. But that is not what I claimed.

    Also, tobyr, it would be very, very helpful if you could read up on PF's reply and quote system. You're mangling it right now and it makes your posts hard to read. :biggrin:

    The "Reply" button will quote the post, pasting it into the reply box immediately. The "+Quote" button will add the post to a que, and you can quote several posts and then scroll down and click on "Insert Quotes" at the bottom left of the reply box to insert all the quoted posts into the reply box. (Don't put your own text in between the the quote tags, which are the "quote" and "/quote" you see at the beginning and end of each quoted post, except they have brackets instead of quotations around the words)
     
  19. Apr 20, 2016 #18
    In saying perhaps Mars had just been re-positioned I was trying to be politic. I still believe it developed along side Earth. I do not know physics but I know co incidences rarely are. Did you read the link? Cool huh?

    I'll read the PF's reply and quote system as soon as I locate it and before I reply to anything else.
     
  20. Apr 20, 2016 #19

    Drakkith

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    I'll look around when I get the chance and see if I can find the info. I know it's around here somewhere.
     
  21. Apr 20, 2016 #20
    Mars sits firmly in the trend of density geting lower with higher distance from the sun, suggesting it is where it was. The result is the same when you analyze some isotope ratios. Moving planets around would cause crazy climate variations unlike anything deductible from surface properties. There is a great debate whether Mars was ever really much warmer in the past, or it just had much denser atmosphere and warm-based glaciers feeding most of the fluvial activity.
    Despite what you may think or simulate the Lagrange points are not stable for any mass of the 'Trojan' object. There is a very popular hypothesis that once there was a Mars-sized planet near the Lagrange point on Earth's orbit.... And thats why we now have the Moon. Do you want to crash Mars into 'Earth-1'? Very bad idea.
     
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