[meteorite-list] NASA Checking on Rover Spirit During Martian Spring

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Wed, 5 Jan 2011 08:34:32 -0800 (PST)
Message-ID: <201101051634.p05GYWpB000909_at_zagami.jpl.nasa.gov>

http://www.jpl.nasa.gov/news/news.cfm?release=2011-003

NASA Checking on Rover Spirit During Martian Spring
Jet Propulsion Laboratory
January 04, 2011

Mars Exploration Rover Mission Status Report

PASADENA, Calif. -- Nine months after last hearing from the Mars rover
Spirit, NASA is stepping up efforts to regain communications with the
rover before spring ends on southern Mars in mid-March.

Spirit landed on Mars Jan. 4, 2004 (Universal Time; Jan. 3, Pacific
Time) for a mission designed to last for three months. After
accomplishing its prime-mission goals, Spirit worked for more than five
years in bonus-time extended missions.

"The amount of solar energy available for Spirit is still increasing
every day for the next few months," said Mars Exploration Rover Project
Manager John Callas of NASA's Jet Propulsion Laboratory, Pasadena,
Calif. "As long as that's the case, we will do all we can to increase
the chances of hearing from the rover again."

After mid-March, prospects for reviving Spirit would begin to drop.
Communication strategies would change based on reasoning that Spirit's
silence is due to factors beyond just a low-power condition.
Mission-ending damage from the cold experienced by Spirit in the past
Martian winter is a real possibility.

The rover's motors worked far beyond their design life, but eventually,
Spirit lost use of drive motors on two of its six wheels. This left it
unable to obtain a favorable tilt for solar energy during the rover's
fourth Martian winter, which began last May.

Spirit and its twin, Opportunity, which landed three weeks after Spirit
and is still active, both have made important discoveries about wet
environments on ancient Mars that may have been favorable for supporting
microbial life.

Spirit last communicated on March 22, 2010. The rover team had
anticipated that the rover would enter a low-power fault mode with
minimal activity except charging and heating the batteries and keeping
its clock running. With most heaters shut off, Spirit's internal
temperatures dipped lower than ever before on Mars. That stress could
have caused damage, such as impaired electrical connections, that would
prevent reawakening or, even if Spirit returns to operation, would
reduce its capabilities.

Southern-Mars spring began in November 2010. Even before that, NASA's
Deep Space Network of antennas in California, Spain and Australia has
been listening for Spirit daily. The rover team has also been sending
commands to elicit a response from the rover even if the rover has lost
track of time.

Now, the monitoring is being increased. Additional listening periods
include times when Spirit might mistake a signal from NASA's Mars
Reconnaissance Orbiter as a signal from Earth and respond to such a
signal. Commands for a beep from Spirit will be sent at additional times
to cover a wider range of times-of-day on Mars when Spirit might awaken.
Also, NASA is listening on a wider range of frequencies to cover more
possibilities of temperature effects on Spirit's radio systems.

JPL, a division of the California Institute of Technology in Pasadena,
manages the Mars Exploration Rover project for NASA's Science Mission
Directorate, Washington.

Guy Webster 818-354-6278
Jet Propulsion Laboratory, Pasadena, Calif.
Guy.Webster at jpl.nasa.gov

2011-003
Received on Wed 05 Jan 2011 11:34:32 AM PST