It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Some features of ATS will be disabled while you continue to use an ad-blocker.
Aura, NASA's newest Earth Observing Satellite, has turned up its first mystery: What happened to the carbon monoxide?
Scientists have long recognized that a sizeable ozone cloud might exist in the tropics over the Atlantic Ocean. Until Aura was launched they had to depend on aircraft readings to detect it, but aircraft can't provide the continuous monitoring needed to develop year-round models.
AURA'S OZONE Monitoring Instrument (OMI) picked up a huge ozone cloud stretching from eastern Brazil into equatorial Africa. The size of the cloud was so great that the Tropospheric Emission Spectrometer was pressed into service to investigate its properties. TES can distinguish tropospheric from stratospheric ozone--identifying the "bad" ozone associated with air pollution from the "good" ozone higher up that shields the Earth from ultraviolet radiation.
OMI found elevated readings of nitrogen dioxide, a precursor for tropical ozone. But TES turned up a mystery. It couldn't detect carbon monoxide, a common companion to ozone produced by large-scale biomass burning, the likely origin of the ozone cloud over the Atlantic.
Since the instruments have been checked out, it's not clear what is going on. The explanation might come from a better understanding of trace gas transfers from the stratosphere to the troposphere, one of Aura's scientific challenges.
The Aura instrument package says the planet's most famous ozone story, the "ozone hole" over Antarctica, is slightly smaller and has less depth this year than in the past. This year's hole has an average measurement about 16% smaller than previous high readings, Aura Project Scientist Mark Schoeberl reported at the American Geophysical Union's fall meeting here last month.
The spacecraft, which was launched July 15, has completed checkouts of its four instruments. Three are working nominally, but there's disappointment with the High-Resolution Dynamics Limb Sounder (Hirdls) because a piece of kapton insulating blanket apparently tore loose during launch depressurization and is blocking 80% of Hirdls' infrared viewing mirror. Hirdls is to study long-lived trace gases, water vapor, temperature and aerosols in the upper troposphere, stratosphere and mesosphere. One of its key goals is to separate naturally-occurring ozone from man-made.
Designed by the University of Colorado, the National Center for Atmospheric Research, Oxford University and Rutherford Appleton Laboratory, Hirdls was built by Lockheed Martin. Goddard Space Flight Center's mission controllers are "flexing" the instrument in progressively more radical steps to see if they can dislodge the kapton.
The blockage isn't preventing Hirdls' vertical scan but is greatly limiting its horizontal capability, Co-Principal Investigator John Gille said. If it can't be removed, the instrument can still provide useful horizontal data, but at a greatly reduced acquisition rate.