This glossary covers words that you will come across on this website.
A Galaxy is a massive system of stars, gas, dust and dark matter all bound together by gravity. The name is from the Greek root galaxias [γαλαξίας], meaning "milky," a reference to the Milky Way galaxy.
- Galaxy Names
The letters indicate the catalogue listing of the galaxy. Galaxies are listed in several different catalogues. The most common catalogue is ‘NGC’, which stands for New General Catalogue. Other catalogues include M (Messier), ESO (European Southern Observatory), IRAS (Infrared Astronomical Satellite), MrK (Markarian), and UGC (Uppsala General Catalogue).