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The main orbit change maneuver is a maneuver that transforms a circular orbit of radius "r" in to a different circular orbit or radius "R", where R≠r.

This type of orbit change is some times called a two-burn transfer. One burn must be done to accelerate the ship into a more eccentric orbit in order to leave the first circular orbit, and then a second burn to accelerate the ship into the final circular orbit.

A special type of two burn transfer is called the Hohmann transfer. The Hohmann transfer is the most fuel efficient transfer possible for increasing or decreasing the radius of an orbit.

The special parameter of the Hohmann transfer orbit is that it is an elliptical orbit whose periapse and apoapse co-inside with the initial and final circular orbits respectively.

If a ship is accelerated to such an extent that its eccentricity is e>1, then the ship will no longer be in orbit around Earth; it will have escaped Earth's gravity. For example, if a space ship is in a circular orbit around Earth at an altitude of 600km, it will be travelling at approximately 7.9km/s. In order for this ship to escape earth’s gravity, it must accelerate to a velocity of 11.8km/s.

The Slingshot maneuver is a special maneuver used when a ship or satellite is travelling to a distant planet. The slingshot maneuver has the effect of giving the ship a boost of velocity.