Solar System

The Astronomical Unit (AU) is the distance from the Sun to the Earth; this is 93 million miles (150 million km)

Additional features:

Asteroid belt between Mars and Jupiter https://en.wikipedia.org/wiki/Asteroid_belt

Kuiper Belt beyond Neptune - Pluto is a Dwarf Planet / Kuiper Belt Object (KBO)

https://en.wikipedia.org/wiki/Kuiper_belt

Oort Cloud further out still https://en.wikipedia.org/wiki/Oort_cloud