Full phase Earth from the lunar surface?

Discussion in 'Astronomy, Exobiology, & Cosmology' started by Exoscientist, May 19, 2014.

  1. Exoscientist Mathematician Registered Senior Member

    Messages:
    139
    The full Moon sometimes looks huge when it's low on the horizon. I was wondering if the same effect would occur on the Moon if we saw a full phase Earth from the lunar surface.

    There haven't been many pictures taken from the surface of the Moon that show the Earth. Here's one:

    Please Register or Log in to view the hidden image!





    The Earth can look pretty large low on the horizon from lunar orbit even when not at full phase as shown by this Apollo 11 image taken from orbit:

    Please Register or Log in to view the hidden image!



    Are there images taken from the lunar surface either by robots or manned missions that show the Earth rise at or close to full phase?

    Nice article by Dr. Paul Spudis:

    Earth Rising.
    Earth as seen from the Moon is always in the same place – true or false? It depends.
    By Paul D. Spudis
    May 15, 2014
    http://www.airspacemag.com/daily-planet/earth-rising-180951474/#ixzz321FRfV82

    I wonder if a Google Lunar X-Prize entrant could land at one of the locations where Earthrise would be visible.

    Bob Clark
     
    Last edited: May 19, 2014
  2. Google AdSense Guest Advertisement



    to hide all adverts.
  3. paddoboy Valued Senior Member

    Messages:
    27,543
  4. Google AdSense Guest Advertisement



    to hide all adverts.
  5. origin Heading towards oblivion Valued Senior Member

    Messages:
    11,888
    The moon only looks larger on the horizon it is not actually larger so a picture will not show the moon as being larger. It is an optical illusion because when the moon is high in the sky there is nothing to compair it to. The moon at the horizon covers the same amount of degrees as it does at its zenith. Here is a really strange trick that works, when the moon is rising and it will looks big, turn around so your back is facing the moon and bend over and look at the moon through your legs, it will no longer look big it will look normal sized. This works apparently because the unfamiliar orientation no longer has our minds compairing the moon to the familiar horizon. I recommend doing this in your backyard away from people....

    Please Register or Log in to view the hidden image!

     
  6. Google AdSense Guest Advertisement



    to hide all adverts.
  7. Exoscientist Mathematician Registered Senior Member

    Messages:
    139

    I don't know if a picture would not show it "larger" since some optical illusions still work in photos.

    [video=youtube;Ttd0YjXF0no]https://www.youtube.com/watch?v=Ttd0YjXF0no[/video]

    Bob Clark
     
  8. leopold Valued Senior Member

    Messages:
    17,455
    it has to be something other than an optical illusion.
    i've seen the full moon on the horizon and it looked really huge, as in gigantic.
    if it was some kind of "comparison" type of thing the moon would look like that ALL the time it was on the horizon, but it doesn't.
     
  9. Russ_Watters Not a Trump supporter... Valued Senior Member

    Messages:
    5,051
    You are missing the point: if you take pictures of the moon at different elexations with the same camera, you can measure the resulting images to see if they are the same size or not.

    The only real effect here is that the atmosphere stretches objects near the horizon under certain conditions. But if that were part of this, you wouldn't be noticing the moon being big, you'd notice it being oval shaped.
     
  10. origin Heading towards oblivion Valued Senior Member

    Messages:
    11,888
    Do an experiment. When you see this 'huge' moon hold you hand out at arms length and use your thumb or a digit to almost but not quite cover the moon and then try it again later in the night when the moon is 'smaller', and see if the moon changed sizes.
     
  11. Exoscientist Mathematician Registered Senior Member

    Messages:
    139

    OK. But illusions of perspective can still hold in images. Look for example at the image at the link provided by paddoboy:

    http://science.howstuffworks.com/question491.htm

    The image of the guy in front looks smaller than the image to the rear. But by moving the front image to the back you see they are the same size.

    Bob Clark
     
  12. paddoboy Valued Senior Member

    Messages:
    27,543
  13. Russ_Watters Not a Trump supporter... Valued Senior Member

    Messages:
    5,051
    Please go back and read my previous post: illusions of perspective are easily resolved when comparing photos.
     
  14. leopold Valued Senior Member

    Messages:
    17,455
    i've only witnessed this phenomenon once, about 20 years ago.
    to be honest, it scared the hell out of me.
    if i squinted i' might have seen apollo 11s landing site.
     
  15. origin Heading towards oblivion Valued Senior Member

    Messages:
    11,888
    Had you ingested mushrooms or something prior to this scary moon sighting?
     
    Last edited: May 20, 2014
  16. Exoscientist Mathematician Registered Senior Member

    Messages:
    139
  17. Exoscientist Mathematician Registered Senior Member

    Messages:
    139

    We are agreed on that. The size of the foreground and background figures in the paddoboy link can be measured to be the same by a ruler. Nevertheless the illusion still persists that the front one is smaller.

    Bob Clark
     

Share This Page