The range of different sizes that galaxies are, is amazing. We live in the Milky Way galaxy, which is a very large, spiral galaxy. Birth Galaxies, like stars, are born from gigantic cosmic clouds . Scientists and Astronomers believe that galaxies start out with small pieces, such as gas clouds and star clusters, that slowly merge together. Galaxies are most likely born from cosmic clouds that are made of Hydrogen and Helium , the reproductive ingredients for stars.
Stars are the life force of a galaxy.
The cosmic cloud is then shaped by a combination of gravity, gas pressure, rotation, and radiation. Galaxies are the birth place of stars. Galaxies are born and are growing every single day in our infinitely expanding universe. Therefore, viewing galaxies in their different stages of adolescence, with the Hubble telescope, is a lot easier than expected. There is an enormous number of different activity that goes on within a galaxy.