PASADENA, Calif., March 14 (UPI) -- Engineers have revived a key science experiment on the Mars Odyssey spacecraft that had been silenced since August by an unknown technical problem.
NASA had suspended efforts to troubleshoot the failed Martian Radiation Environment Experiment, which was added to the Mars Odyssey mission in an attempt to gather information about the amount, types and effects of dangerous radiation exposure that future Mars-bound astronaut crews might face.
Space radiation comes from cosmic rays emitted by the sun, as well as from stars beyond our solar system. The radiation can trigger cancer, as well as damage the central nervous system and human DNA.
NASA has flown similar radiation-monitoring devices on the space shuttle and the International Space Station, but the Mars experiment, nicknamed MARIE, is the first to fly outside the protective envelope of Earth's magnetosphere, which blocks most space radiation from reaching the planet's surface.
"We're very concerned with the health and safety of the astronauts," said Jeffrey Sutton, director of the NASA-funded National Space Biomedical Research Institute, based at Baylor University in Houston.
Unlike Earth, Mars does not have a global magnetic field to shield it from solar flares and cosmic rays. The planet also lacks atmosphere -- Mars' atmosphere is less than 1 percent as thick as Earth's -- which also blocks radiation from the planet's surface.
Measurements made by the Martian radiation-environment experiment during Odyssey's cruise to Mars indicate that the daily dose of radiation experienced by astronauts on their way from Earth to Mars would be more than twice the dose endured by astronauts on the International Space Station, said MARIE principal investigator Francis Cucinotta, with NASA's Johnson Space Center.
After a seven-month hiatus, MARIE resumed its scientific investigation on Wednesday after engineers successfully re-established communications with the instrument.
"This is very exciting," said Mars Odyssey project manger Roger Gibbs, with the Jet Propulsion Laboratory in Pasadena. "We now have the entire payload working."
Preliminary tests indicate a software problem was to blame for MARIE's shutdown.
Mars Odyssey began a two-year mapping mission on Feb. 19.
(Reported by Irene Brown at Cape Canaveral, Fla.)
