Apogee Motor Firing #4, a 50-minute burn using the ACS thrusters, was performed successfully on Friday. Our perigee altitude is now greater than 10,000 km as it continues to move away from the Earth toward a circular GEO orbit. The Slosh Tiger Team is recommending some tweaking to the ACS controller to allow main engine burns to resume. We are meeting today to discuss a "hybrid" burn for Sunday, 40 minutes on the ACS thrusters, followed by a 10-minute main engine burn.
Now that perigee is moving above the inner radiation belt it looks like EVE will no longer to able to measure trapped energetic protons and will have to wait for a solar signal. I hope these proton measurements can be used to improve our models of the inner radiation belt, especially AP8MIN, for the conditions present during this extended solar minimum period. That's what Living With a Star is all about!


February 18, 2010: Last week, on Feb. 11th, the Solar Dynamics Observatory (SDO) lifted off from Cape Canaveral on a five-year mission to study the sun. Researchers have called the advanced spacecraft the "crown jewel" of NASA's heliophysics fleet. SDO will beam back IMAX-quality images of solar explosions and peer beneath the stellar surface to see the sun's magnetic dynamo in action.