Missing Venus

Japan’s AKATSUKI unmanned space probe fires its thrusters to slow down enough to be captured into an orbit around Venus, a maneuver which will take place mostly in the planet’s shadow, out of communication with Earth. But when ground controllers reacquire communications with AKATSUKI, it is in safe mode, and not in its predicted orbit around Venus. The main orbital engine, damaged by overheating due to salt deposits on a fuel valve, fired for less than three minutes and cannot safely be fired again, leaving AKATSUKI into a solar orbit. Mission planners put AKATSUKI into a hibernation mode to preserve it for another opportunity to orbit Venus in 2015.