Here is the SDO orbit so far. The initial GTO, two intermediate orbits, and the estimated final orbit are shown to scale. Apogee Motor Firings (AMFs) all take place at the apogee of the orbit (the left side of the diagram) and are designed to lift the perigee (where SDO is closest to the Earth) up to a geosynchronous altitude. A few trim maneuvers will then move SDO into its final orbit. Perigee values are altitudes (height above the Earth).