Lagrange Points: Parking Places in Space (2017)

A Lagrange point is a location in space where the combined gravitational forces of two large bodies, such as Earth and the sun or Earth and the moon, equal the centrifugal force felt by a much smaller third body. At this point, with the Earth, moon and sun behind it, a spacecraft can get a clear view of deep space. The third Lagrange point, L3, lies behind the sun, opposite Earth’s orbit.

Source: www.space.com