Moon, Jupiter, Mercury, September 24, 2003. This peaceful pre-dawn image over Georgian Bay shows a close grouping of the Moon and two very different planets. Jupiter is the bright dot to the upper right of the Moon, and Mercury is the faint dot that makes a triangle below them. It looks as though Mercury is the farthest away, but at the time this photo was taken the Moon was about 371,000 km away, Mercury was 132 million km away, and Jupiter was 941 million km away. Mercury is very small, not very reflective and only 38 percent illuminated at this time. In addition, Mercury was close to the horizon, so its light was getting absorbed by much of our atmosphere. Jupiter, although much farther away, is very large, very reflective, 100 percent illuminated, and its light has travelled through less of our atmosphere.
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