Mars Odyssey Mission Status - November 26, 2003

MEDIA RELATIONS OFFICE
JET PROPULSION LABORATORY
CALIFORNIA INSTITUTE OF TECHNOLOGY
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION
PASADENA, CALIF. 91109.  TELEPHONE (818) 354-5011
http://www.jpl.nasa.gov 

Guy Webster (818) 354-6278
Jet Propulsion Laboratory, Pasadena, Calif.

News Release: 2003-156                           November 26, 2003

Mars Odyssey Mission Status

The martian radiation environment experiment on NASA's 2001 Mars
Odyssey orbiter has collected data continuously from the start of the
Odyssey mapping mission in March 2002 until late last month.  The
instrument has successfully monitored space radiation to evaluate the
risks to future Mars-bound astronauts.  Its measurements are the first
of their kind to be obtained during an interplanetary cruise and in
orbit around another planet.

On Oct. 28, 2003, during a period of intense solar activity, the
instrument stopped working properly.  Controllers' efforts to restore
the instrument to normal operations have not been successful.  These
efforts will continue for the next several weeks or months. 

The martian radiation environment experiment detects energetic charged
particles, including galactic cosmic rays and particles emitted by the
Sun in coronal mass ejections.  The dose equivalent from galactic
cosmic rays as measured by the instrument agrees well with predictions
based on modeling. Validation of radiation models is a crucial step in
predicting radiation-related health risks for crews of future
missions.

"Even if the instrument provides no additional data in the future, it
has been a great success at characterizing the radiation environment
that a crewed mission to Mars would need to anticipate," said Dr.
Jeffrey Plaut, project scientist for Mars Odyssey at NASA's Jet
Propulsion Laboratory, Pasadena, Calif.

JPL manages the Mars Odyssey and Global Surveyor missions for NASA's
Office of Space Science, Washington, D.C. Investigators at Arizona
State University, Tempe; University of Arizona, Tucson; NASA's Johnson
Space Center, Houston; the Russian Aviation and Space Agency, Moscow;
and Los Alamos National Laboratory, Los Alamos, N.M., built and
operate Odyssey science instruments. Information about NASA's Mars
exploration program is available on the Internet at: 

http://mars.jpl.nasa.gov/ .

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