[meteorite-list] Mars Reconnaissance Orbiter Resumes Observations

From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Fri, 18 Dec 2009 13:14:21 -0800 (PST)
Message-ID: <200912182114.nBILELv9026134_at_zagami.jpl.nasa.gov>

http://www.jpl.nasa.gov/news/news.cfm?release=2009-198

NASA's Mars Reconnaissance Orbiter Resumes Observations
Jet Propulsion Laboratory
December 16, 2009

PASADENA, Calif. -- Researchers are receiving new science data from
NASA's Mars Reconnaissance Orbiter after the spacecraft's six science
instruments resumed observations today.

Observations had been suspended since a computer reset Aug. 26. During
the time since then, engineers analyzed a series of previous computer
resets by the spacecraft and completed preventive care to guard against
a vulnerability identified by that analysis.

In addition to the Aug. 26 event, the orbiter had spontaneously reset
its computer three times earlier this year: Feb. 23, June 4 and Aug. 6.
The mission had returned to full science operations within a few days
after the first three. The decreasing intervals between the resets
prompted the team to perform a more extensive analysis after the fourth
one.

"It's good to have the instruments back on," said Mars Reconnaissance
Orbiter Mission Manager Dan Johnston of NASA's Jet Propulsion
Laboratory, Pasadena, Calif. "This has been a long stand-down. Now we're
ready to resume our science and relay mission."

Engineers have not identified a root cause for the four reset events,
but the team has added protections for the spacecraft and expects to
obtain more diagnostic information in the event of another reset.

Two weeks ago, engineers rewrote selected files in the orbiter's
non-volatile memory, where information is preserved even if a reset
interrupts power. This was done to remove a vulnerability that had been
identified for an unlikely scenario of two resets within a minute of
each other. On Dec. 8, engineers commanded the orbiter out of the
precautionary, minimum-activity status called "safe mode" that they had
kept it in since August. Additional steps, including a change of
spacecraft orientation to point the instruments downward at Mars,
enabled the spacecraft's science instruments to resume observations.

"The orbiter's six instruments will continue examining the atmosphere,
surface and subsurface of Mars, including areas of interest as potential
landing sites for future missions," said JPL's Rich Zurek, Mars
Reconnaissance Orbiter project scientist. "It is northern spring in the
northern hemisphere on Mars, and we are eager to take advantage of the
good visibility provided by the relatively dust-free atmosphere present
at this season. A major goal of the mission is to look at changes on
Mars. For example, the instruments will observe the changing polar caps,
examining the extent and composition of the retreating north polar
frosts and the growth of the south polar cap during this period."

Launched Aug. 12, 2005, the orbiter reached Mars the following year to
begin a two-year primary science phase that was completed last year. It
has returned more data about Mars than all other spacecraft combined.
Its findings indicate a complex Martian history of climate change that
produced a diversity of past watery environments over hundreds of
millions of years.

The Mars Reconnaissance Orbiter remains an important asset for exploring
Mars and serving as a communications relay for spacecraft on the
planet's surface. NASA's other active Mars orbiter, Mars Odyssey, was
also briefly in safe mode for a portion of last week, but has also
resumed relay and science operations.

More information about the Mars Reconnaissance Orbiter is online at:
http://www.nasa.gov/mro or http://marsprogram.jpl.nasa.gov/mro/.

NASA's Jet Propulsion Laboratory in Pasadena, Calif., manages the Mars
Reconnaissance Orbiter for NASA's Science Mission Directorate in
Washington. Lockheed Martin Space Systems in Denver built the
spacecraft. JPL is a division of the California Institute of Technology
in Pasadena.

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

Dwayne Brown 202-358-1726
NASA Headquarters, Washington
dwayne.c.brown at nasa.gov

2009-198
Received on Fri 18 Dec 2009 04:14:21 PM PST