University of Edinburgh
 

BSL Astronomy Glossary - nebula - definition

Definition: A nebula appears as a fuzzy patch of light in the night sky. If you zoom in on a nebula with a high-powered telescope, sometimes you would find that it is a group of stars. Sometimes a cloud of gas within our own galaxy, the Milky Way, causes a nebula and sometimes a nebula is, in fact, an entirely different galaxy, far away in space.