Because the moon isn't that close to earth. Both objects are tiny specs on the scale of the distances between them. Google image search for "Earth from moon" and you will see that the earth only covers 3-4 degrees of the moon's sky. That's not anywhere close to enough to protect the entire earth-facing surface of the moon.
Reader Comments (Page 1 of 1)
SuperQ @ Dec 6th 2007 12:41PM
Because the moon isn't that close to earth. Both objects are tiny specs on the scale of the distances between them. Google image search for "Earth from moon" and you will see that the earth only covers 3-4 degrees of the moon's sky. That's not anywhere close to enough to protect the entire earth-facing surface of the moon.