Photography of the night sky and celestial bodies. This can be done by attaching a camera to a telescope (typically with a T-mount adapter) or simply by pointing a camera and a lens at the night sky. Astrophotography requires very long time exposures, so all-mechanical cameras or electronic cameras which draw no battery power when the shutter is open are very useful - you don’t want your fabulous night sky photo to fail when the battery expires halfway through the night. Another problem in the field of astrophotography is the fact that the night sky appears to turn, thanks to the rotation of the Earth. This can yield interesting curved star trail patterns, but that’s obviously not always desirable.
Astrophotography is a specialized type of photography that entails making photographs of astronomical objects in the sky such as the Moon, Sun, planets, stars, and deep sky objects such as star clusters and galaxies.