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xkcd - Gravity well pic.

  • 02-01-2010 5:49pm
    #1
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 93,583 Mod ✭✭✭✭


    http://imgs.xkcd.com/comics/gravity_wells_large.png

    Graphic representation of how much energy it takes to travel between the planets


Comments

  • #2
    NoQuarter
    Registered Users, Registered Users 2 Posts: 4,632 ✭✭✭NoQuarter


    Is that true? Could you throw a baseball off phobos into space??


  • #3
    Tears in Rain
    Registered Users, Registered Users 2 Posts: 267 ✭✭Tears in Rain


    The escape velocity on the surface of Phobos is roughly 10m/s, while a world-class baseball pitcher can just about exceed 100mph in a pitch, which corresponds to roughly 40m/s, so not only is it possible, it's not even difficult!

    Perhaps even more interestingly, it might be possible for a world-class athlete to jump, vertically, off Phobos' sister moon Deimos and escape its gravity completely!

    (Someone might want to double check my back-of-napkin calculations, I'm basing this off wikipedia telling me that a vertical jump over 40 or 50 inches is considered outstanding, and Deimos having an escape velocity of 5m/s)


  • #4
    Capt'n Midnight
    Moderators, Recreation & Hobbies Moderators, Science, Health & Environment Moderators, Technology & Internet Moderators Posts: 93,583 Mod ✭✭✭✭Capt'n Midnight


    Tears in Rain wrote: »
    TPerhaps even more interestingly, it might be possible for a world-class athlete to jump, vertically, off Phobos' sister moon Deimos and escape its gravity completely!
    Don't forget that you the moon will still be orbiting Mars and IIRC you will meet the moon again in about two orbits.


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