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Moon is drawing away from Earth

  1. Jul 27, 2015 #1
    Hi all

    It's a well known fact that the moon is drawing away from earth by 3.82 ± 0.07 cm/year.

    I was googling a lot to find the exact distance between earth - moon

    that this data was measured.

    A plain number or a link will be much appreciated.

    Thanks in advance

    Elistein
     
  2. jcsd
  3. Jul 27, 2015 #2
  4. Jul 27, 2015 #3
    Hi Dr. Courtney

    Thanks for your reply.

    Yes, I know about the min, max and average distance.

    What I'm interested: what was the exact distance at the time this data was determined:

    "The Moon is spiraling away from the Earth at an average rate of 3.8 cm (1.5 in) per year"
     
  5. Jul 27, 2015 #4

    russ_watters

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    Staff: Mentor

    There can't be an exact/single value for something that is an average. The value was almost certainly derived from decades of lunar ranging experiments.
     
  6. Jul 27, 2015 #5

    Janus

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    Staff Emeritus
    Science Advisor
    Gold Member

    If you want the distance from Earth to Moon at any given time, go here:

    http://ssd.jpl.nasa.gov/horizons.cgi#top

    And set the Moon as the target body.

    The time span setting will allow you to set the date, time, time duration and time steps for the generated list. Under table settings, you can choose which properties you want to see in the list.
     
  7. Jul 27, 2015 #6
    russ_watters and Janus

    Thanks for your replies. I'll look into it right away
     
  8. Jul 27, 2015 #7
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