Posted on behalf of Ron Cowen.
NASA’s Deep Impact spacecraft is in deep trouble. The craft, famous for blasting a projectile into the Comet Tempel 1 in 2005, lost contact with Earth sometime between 11 August and 14 August. Recent commands to put the craft in hibernation, or safe mode, were unsuccessful, and Deep Impact is now spinning out of control, says principal investigator Michael A’Hearn of the University of Maryland in College Park. The mission was renamed Epoxi when it was extended to observe comets and stars with transiting exoplanets.
Engineers have traced the problem to a software-communications glitch that reset the craft’s computer. They are now working on commands that could bring Deep Impact back into operation. They may try to communicate with the spacecraft this weekend, but the team first has to figure out its most likely orientation and whether to broadcast signals to the vehicle’s high-gain or low-gain antenna.
Mission scientists are racing against the clock because the craft’s batteries rely on power provided by Deep Impact’s solar panels. If the panels on the wayward craft happen to be pointing in a direction where they receive partial sunlight, the batteries could last for a few months. But if the panels are pointed away from the Sun, the batteries would die in just a few days. Once the batteries are gone, Deep Impact can no longer be revived, A’Hearn says.
One casualty of the mishap is that scientists have not received any of the expected images the craft was scheduled to take in August of Comet ISON, the icy space rock that could make a spectacle in the inner Solar System this fall before diving into the Sun, A’Hearn says.