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← The Moons of Mars Explained -- Phobos & Deimos

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Showing Revision 2 created 04/11/2015 by Valentine Anderson.

  1. The moons of Mars explained.
  2. Mars has two moons, Phobos and Deimos.
  3. They are really tiny. How tiny?
  4. Compared to Mars or our own Moon,
  5. pretty tiny.
  6. Although ‘tiny’ is a matter of opinion.
  7. Their surface area is up close to some
    of the smallest states on Earth,
  8. like Luxembourg and Malta.
  9. Although Phobos and Deimos are
    in no way lightweight,
  10. in reality, their gravitational pull
    isn’t even strong enough
  11. to bring them into spherical form.
  12. So they look more like huge
    potatoes than moons.
  13. The most popular theory of their origin
  14. is that they were once
    part of the asteroid belt,
  15. until Jupiter’s massive gravity
    kicked them out of it,
  16. so Mars could catch them.
  17. Phobos orbits Mars at a average distance
    of 9,400 kilometres, once every 7½ hours.
  18. It’s on a collision course, and gets
    2 metres closer to Mars every year.
  19. In 50 to 100 million years, it will either
    be ripped to pieces by Mars’s gravity
  20. and be transformed into a beautiful ring,
  21. or it will crash into Mars.
  22. The energy released in this collision
    would kill everything on the small planet.
  23. So, if there are humans on Mars by then,
    they should build very strong bunkers.
  24. Smaller Deimos, on the other
    hand, is slowly escaping Mars.
  25. Eventually, it will fly off into space
    and leave a lonely red planet behind.
  26. So, in a few hundred million years,
    Mars will be moonless and on its own.
  27. Unless it manages to catch
    itself another asteroid.