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

Moon for mars

  1. May 15, 2004 #1


    User Avatar

    I was just wondering if anyone has ever studyed what a large moon like ours would do to mars? Maybe the tektonic strain could be enough to warm the core and start volcanic activity.
    Could mars have once had a large moon that was lost, maybe the asteroid belt could once have been a large body.

  2. jcsd
  3. May 15, 2004 #2


    User Avatar
    Science Advisor
    Gold Member

    I think you could safely say the tidal forces between mars and the moon if they were orbiting each other would be a very long way from being able to cause volcanic activity (just think it takes a Jupiter sized object to cause volcanic activty in the Jovian moons)
  4. May 15, 2004 #3
    Judging from our experience, I'm guessing that it would not only activate volcanoes and tectonic plates, but it would also upheave the permafrost underneath the ground. That would give it a substantial atmosphere, and a shallow ocean. Perhaps if a moon or giant comet nuclei (Chiron?) were slung gravitationally from its planet, and somehow guided to Martian orbit, then you'd have a handy-dandy planetary igniter.

    Lunaforming should be an interesting space profession.
  5. May 15, 2004 #4
    Hello Mem,

    Very interesting question. I’ve never considered this. Perhaps with a big enough moon there would be enough stress to restart tectonic activity.
    As for what Jcsd said: Io’s extreme volcanic activity is due not only to the gravitational pull of Jupiter, but also from Europa and Ganymede. Io is constantly being ‘stretched’ and ‘squeezed’ because its orbit changes slightly from the effects of those large moons.
  6. May 18, 2004 #5


    User Avatar

    My thinking in this is that some event quickly threw mars into a state of deminishing atmosphere resulting in the planet going into a freeze/dry situation.
    Also since it is found that our own moon is not made of earth material, then some event also placed our moon in orbit. I may be ill informed, but I uderstand that the continent of pangea remained for many many million years before breaking up. Could the theoretical introduction of a large orbiting body have placed enough tidal forces upon the land mass to start a breakup of a single land mass into what we have as tektonic plate movement?
    I would also wonder if mars shows any sign of a magnetic feild indicating a molten core? If this field is locked into rock such as on earth, then it could basicaly show at what point the core activity slowed down.
    It would also be nice to look at the evedent large water bodies shorelines to see if signs of tidal movement were there. I can't imagine what would produce these tidal activities if not for a large orbiting body?

    As for the jovian system, It realy must be thought of in it's own context. The massive radiation saturation of the moons would in no doubt help in core warming.
    In our own case, If we were to looose the moon exactly what would be the tektonic reprocutions? I'm sure the radioactive material in the mantle could keep the core hot, But without our orbiting "mixer", could plate movement remain as it is?
    I don't meen to say that some advanced being moved the moon from mars to here, but if we think about it, mankind is coming to a point where large bodies could be moved into a very precise orbit. With the ability of gravitational positioning assist for our probes, and the precise placement of such, It is only a new class of large body control methodes that hold us back from as Lord flashheart coined "lunaforming" of many celestial bodies.
    Thanks to all for the input and discusion.
  7. May 20, 2004 #6
    Actually, Mars did once have a magnetic field. In fact, it was about 30 times stronger than Earths is today! Evidence for this is in the ancient lava flows. As the lava cooled, particles inside oriented themselves with the magnetic field of the planet.

    As for Pangea, some models show that Pangea was only the last great grouping of all the continents in a long cycle of continental ‘breaking apart and coming together’. The last time this happened was about 350 million years ago, if I’m not mistaken. The moon is at least 3-4 billion years old. Not quite young enough for it to be responsible for a sudden break-up of Pangea.

    From my understanding, back in the ancient Earth’s past, a large, Mars sized object hit the earth. The resulting impact threw up material into Earth orbit, which eventually condensed into our moon. Some say that that impact also gave the Earth it’s tilt. Now, Mars has a similar tilt to the Earth’s. Is it possible that some ancient impact caused that?
    Or, maybe, for a brief period of time, a very large moon orbited Mars. (Think Pluto and Charon) If that large object got caught in Mars orbit, would it have been enough to affect the tilt of the planet’s rotation? And would the addition and then subsequent loss of that object be able to explain Mars’ relatively large orbital eccentricity?

    I have no idea; I’m just throwing these thoughts out there. Maybe someone with a bit more knowledge in this area will be able to answer some of these questions
  8. May 20, 2004 #7


    User Avatar
    Science Advisor

    Speaking of eccentricity, putting a large moon in orbit around Mars would be much more effective if it were in a highly eccentric orbit. It is the changing gravitational stresses as the moon gets closer, then moved farther away, that would stretch and flex the crust of the planet, generating heat. I don't know if this would be enough to activate vulcanism on the planet, of the moon would be a tremendous hotspot!
  9. May 21, 2004 #8
    Let it be known I coined it.

    Hmm, I coined the word? How nifty.

    The priniciple of making a moon can be accomplished by two means:

    1. Transfering a premade lunar body to a different planet system. (I.E. Saturn to Mars)

    2. Making a moon from scratch, by collecting many smaller bodies.

    The second method has the advantage of letting you select the raw materials, and, using kinetic force, the planetoids can be combined. For a brief few seconds after co-impact, the material in the minor planets becomes temporarily amorphous. The material will fuse together, and make a spherical body. If this process were repeated multiple times, (a) huge mass(es) will be formed.

    If Mars really does have a ferrous-nickel core, than the use of asteroids composed of the same elements is preferable, so as to increase the strength of it's b-field. Eventually the magnetosphere will become self-sufficent when the tectonic plates shift again.

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook