[meteorite-list] Deep Impact Spacecraft Is Spinning Out of Control

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Tue, 10 Sep 2013 11:17:00 -0700 (PDT)
Message-ID: <201309101817.r8AIH1CT029200_at_zagami.jpl.nasa.gov>

http://blogs.nature.com/news/

NASA's Deep Impact spacecraft is spinning out of control
Eric Hand
Posted on behalf of Ron Cowen
Nature News Blog
September 5, 2013

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.
Received on Tue 10 Sep 2013 02:17:00 PM PDT