Galaxies

Galaxies

Galaxies are enormous systems containing billions of stars, gas, dust and dark matter, held together by gravity. Unlike most other deep-sky objects we photograph, they lie outside our Milky Way, typically millions or even billions of light-years away.

Galaxy Groups

Galaxies are themselves gathered by gravity into groups and clusters. A single image can therefore capture several physically associated galaxies at once, sometimes interacting with each other through their mutual gravitational attraction. Our own Milky Way belongs to the Local Group, together with Andromeda and dozens of smaller galaxies.