Our Solar System _______________________________________________________________________________________________________________________________________________________________________________________________________________________
5. Orbits
Distances to the Planets and Properties of Orbits Relative to Earth's OrbitDistances in the solar system are often measured in astronomical units (AU).
One astronomical unit is defined as the distance from Earth to the Sun.
1 AU equals about 150 million km.
The following table shows the distances to the planets (the average radius of orbits) in AU.
The table also shows how long it takes each planet to spin on its axis (the length of a day) and how long it takes each planet to complete an orbit (the length of a year); in particular, notice how slowly Venus rotates relative to Earth.
Most of the objects in the solar system share some characteristics, which have to do with the origin and evolution of the actual solar system. Two of them are revolution and rotation