How Many Galaxies Are There In the Universe and Are There More Grains of Sand On Earth Than Stars?

There are more grains of sand on earth than stars in the universe.

The recently published data from Hubble Space Telescope images help confirm scientists long-held suspicion that the universe has many galaxies invisible to ground-based telescopes, so an increase from ten billion galaxies to fifty billion was not unexpected.

Some estimates have gone even higher, up to one hundred billion galaxies.

When you multiply by the average number of stars per galaxy, you get anywhere from 10 to the 20th power to 10 to the 22d power for the estimated number of stars in all the galaxies of all the known universe, 10 to the 20th is a 1 followed by twenty zeroes.

A beach with a coastline of a few kilometers, with sand grains fitting a few to the millimeter, has a mere 10 to the 18th power, or one quintillion, grains, far fewer than the number of stars.

However, if you add up all the grains of sand on all earth’s beaches, in all earth’s mighty deserts and below earth’s oceans, you have handily outnumbered all the stars in the known universe.