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Earth transits the Sun as viewed from Mars in 2005?

  1. Mar 17, 2004 #1
    So I was playing around with Celestia and watching last year's transit of Mercury and this year's transit of Venus. They seemed pretty accurate to diagrams I've seen for ingress/egress locations. Then I got an idea.

    I flew to Mars and went looking for a transit of Earth, and to my surprise I found one, on the November 7th 2005 opposition of Mars (conjuction of Earth? )

    Does anyone know if this is accurate, or how often an occurence this is? It's a shame we won't be able to see it! :frown:
  2. jcsd
  3. Jun 14, 2009 #2
  4. Jul 5, 2009 #3
    5 years too late XD
  5. Jul 5, 2009 #4


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    And Earth, as seen from Mars, will appear the size of the full Phobos! :biggrin:
  6. Jul 6, 2009 #5
    Earth appears significantly smaller than both Phobos and Deimos from Mars even when Mars is near perihelion and Earth near inferior conjunction (aka perihelion opposition of Mars). In the case of Phobos: Ratio of mean true diameters is ~ 12756 : 22.2 and ratio of Mars-centric distances is ~ 55 600 000 : 9 380, thus Earth is 575 times bigger but more than 5900 times further away from Mars than Deimos is, thus apparent diameter of Phobos is at least 10 times bigger than Earth's even in closest approaches of Earth and Mars such as that of August 2003. Consequently during a transit Deimos appears more than 100 times bigger spot than Earth does.

    Just found on wikipedia: http://en.wikipedia.org/wiki/Transit_of_Phobos_from_Mars
    Last edited: Jul 6, 2009
  7. Jul 6, 2009 #6


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    It was a joke. A pun on the indefatigable https://www.physicsforums.com/showthread.php?t=178918&highlight=mars+moon+myth".
    Last edited by a moderator: Apr 24, 2017
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