What is SOHOs orbit?
SOHO is in orbit between the Earth and the Sun. It is about 150,703,456 kilometers (92 million miles) from the Sun and only about 1,528,483 Kilometers (1 million miles) from the Earth (three times farther than the moon). This orbit is around a mathematical point between the Earth and the Sun known as the Lagrange point or the L1 point. The L1 point is a point of equilibrium between the Earth’s and Sun’s gravitational field, that is to say that the pull is equal from both the Sun and the Earth. The L1 point is a point of unstable equilibrium (like a bowl round side up with a marble balanced on it). As a result, we have to compensate for perturbations due to the pull of the planets and the Earth’s moon. Every few months we use a little fuel to fine tune our orbit and keep it from getting too far off track. This is known as “station keeping manoeuvres” No spacecraft is actually orbiting at the L1 point. For SOHO there are two main reasons: the unstable orbit at the L1 point and facility o
