What is galaxies gif?

Galaxies are vast systems of stars, gas, dust, and dark matter held together by gravity. There are estimated to be billions of galaxies in the universe, each containing anywhere from a few hundred billion to a few trillion stars. The shape and structure of galaxies can vary, with some being spiral-shaped like our Milky Way, while others are more elliptical or irregular in shape. Galaxies are believed to have formed through a combination of gravitational attraction and the cooling and condensing of gas and dust in the early universe. They continue to evolve over time through a variety of processes, such as mergers, collisions, and the formation of new stars. The study of galaxies and their properties is a major area of research in astrophysics and cosmology.