How Many Galaxies Are There?

Scientists estimate that there are at least 100 billion galaxies.

Scientists believe there are about 100 billion galaxies, or systems in
space comprised of stars, dust and gas. There is no way for researchers to
view all parts of the universe, so specific areas have been viewed to count
the number of galaxies there in order to create an estimate for the entire
universe. In 2011, the Hubble telescope was used to view an area of the sky
about one-tenth the diameter of the moon as seen from Earth, and about
10,000 galaxies were found in that area of the sky. The number was then
multiplied to estimate the number of galaxies in the universe, but the
actual number might be even higher. For example, one supercomputer
simulation estimated that there could be as many as 500 billion galaxies.
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