Well....not quite. First of all, you do not measure the area of the sky in square inches, but if you held a 1 square inch object at arms length, it would subtend a few degrees on a side. It's best to use angular measure on the sky. For example, the area of the sky in square degrees is close to 40,000. The Moon is 1/2 a degree in diameter.
Inside a 1 degree square patch of the sky, there are about 200x3600 or 720,000 galaxies of all sizes, shapes and distances by the latest estimates from the Hubble Space Telescope. It's a very hard estimate to make, because there are lots of galaxies that we miss because they are too faint, and we only look deeply into a few small patches of the sky. The Hubble Deep Field photo (above) was only about a few arcminutes on a side and it saw about 200 individual galaxies, most of them at distances of several billion light years.
Copyright 1997 Dr. Sten Odenwald
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