A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems

A galaxy is a huge collection of gas, dust, and billions of stars and their solar systems. A galaxy is held together by gravity. Our galaxy, the Milky Way, also has a supermassive black hole in the middle. When you look up at stars in the night sky, you're seeing other stars in the Milky Way.

Galaxies are vast cosmic islands of stars, gas, dust, and dark matter held together by gravity. Hubble's keen eye has revealed intricate details of the shapes, structures, and histories of galaxies — whether alone, as part of small groups, or within immense clusters.