NASA Solar Satellites Headed for the Moon

Recycled Solar Probes Heading For Lunar Orbit
Aviation Week

Two satellites of NASA’s five-member Themis constellation, launched in February 2007 to study geomagnetic storms, are approaching lunar orbit for a new mission called Artemis.

NASA has yet to authorize funding for Artemis (Acceleration Reconnection and Turbulence and Electrodynamics of the Moon’s Interaction with the Sun), but there was no time to wait. Left in their previous orbits, the satellites would have fallen into prolonged periods of deep shadow that likely would have resulted in their demise.

“We started thinking of different methods for saving them – even before they were launched,” says Themis principal investigator Vassilis Angelopoulos, with the University of California at Berkeley. “We realized that if we had enough fuel to change their orbits, the Moon’s gravity would start pulling them up.”

From their new vantage points in front of and behind the Moon, relative to the Sun, the satellites will continue to support the Themis (Time History of Events and Macroscale Interactions During Substorms) mission with collaborative studies, but their main focus will be on solar wind and lunar environmental research.

Read the full story.