Wednesday, March 09, 2011

Crash of Another Climate Satellite Hurts Earth Science

Glory Satellite Rendering
 Image: Pacific Northwest
 National Laboratory

Problems with NASA's the launch vehicle, a Taurus XL rocket, sent the climate probe Glory satellite crashing into the Pacific Ocean last Friday morning. Preliminary data suggest that the rocket's fairing, a nose cone designed to shield Glory during the journey through Earth's atmosphere, did not detach the way it was supposed to. A similar problem two years ago caused the crash of another NASA climate satellite, the Orbiting Carbon Observatory (OCO).  The losses of Glory and the Orbiting Carbon Observatory will make rebuilding that capability harder.

The incident is a blow for climate science and the space agency's efforts to rebuild an Earth observation program weakened by years of lean budgets. It also comes during a protracted spending fight on Capitol Hill in which science agencies have become prime targets for House Republicans' budget ax.

Both satellites were considered key missions for NASA's Earth observation program.  NASA's decision to build and launch a copy of the failed Orbiting Carbon Observatory has taken money away from other key Earth and climate satellite missions, he said, and the loss of Glory could compound that problem.

In 2007, the National Academy of Sciences warned that the nation's Earth observing capability was "at great risk" after cumulative rounds of budget cutting. According to the NAS, the nation's ability to monitor severe weather, fresh water shortages and climate change all depended on increasing NASA's Earth science budget.

Glory was carrying two instruments that scientists hoped would improve the accuracy of climate models. One, the Total Irradiance Monitor (TIM), was designed to extend a 32-year record of fluctuations in the sun's energy output. Those fluctuations can influence Earth's climate over the long term. The amount of sun that reaches Earth, for instance, helps determine the amount of energy that is trapped in Earth's atmosphere by greenhouse gases.

Glory's crash could create a gap in that decades-long record. Glory's TIM was three times more accurate than the instrument it was designed to replace. The older TIM is flying aboard NASA's SORCE satellite, now in its eighth year in space. SORCE was designed to last just two and half years, and its batteries are now failing. (Scientific American, 3/7/2011)

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