An Astronomical Unit (AU) is a distance unit meant to convey the distance between the Earth and the Sun, or more specifically the mean between the Earth's orbit's Aphelion and Perihelion. However, it is now fixed at 149597870700 meters, and only considered a general term for the Earth-Sun distance. An AU is equivalent to:

• about 150 million km.
• about 93 million miles.
• 4.848 × 10^-6 Parsecs.
• 1.581 × 10^-5 light-years.

Some distances in AU: