Universe

Universe

The universe is everything that exists, including galaxies, stars, planets, and all of space itself. It is constantly expanding, and scientists estimate that it is about 13.8 billion years old. The universe contains billions of galaxies, each made up of billions of stars and planets. Studying the universe helps sc...

The universe is everything—stars, planets, galaxies, and all the gas, dust, and energy that exist. It includes all of space and time.

Cosmology is the study of the universe, focusing on its structure, origin, and evolution over time.

The images we see of the farthest galaxies show how they looked billions of years ago because their l...