HU NASA Satellite Mission to Study ‘Night Shining’ Clouds Extended AIM satellite has provided the first global-scale, full-season view of strange, iridescent polar clouds that form 50 miles above Earth’s surface. Hampton, VA - Hampton University recently received a contract increase of $10.2 million from the NASA Goddard Space Flight Center to extend the NASA Aeronomy of Ice in the Mesosphere (AIM) satellite mission for three more years. The HU led NASA AIM is the first satellite dedicated to the study of these noctilucent (NLC) or "night-shining" clouds. They are called "night shining" clouds by observers on the ground because their high altitude allows them to continue reflecting sunlight after the sun has set below the horizon. They form a spectacular silvery blue display visible well into the night. “Hampton University is leading the way in innovative research,” said HU president Dr. William R. Harvey. “This mission is improving scientists’ understanding of global change.” AIM has provided a global-scale view of the clouds over five complete cloud seasons covering both poles and has documented for the first time the entire complex life cycle of NLCs. The satellite is providing an unprecedented horizontal resolution of 3 miles by 3 miles. The AIM baseline mission ended May 31, 2009 but NASA has approved extending the satellite program through September 2012. The funding increase adds to the research base of the HU Center for Atmospheric Sciences, which supports 17 faculty, research professors and post-doctoral employees, 9 support staff and 10 graduate students. "The AIM mission has changed our view of noctilucent clouds,” said AIM Principal Investigator and Co-Director of the HU Center for Atmospheric Sciences Dr. James Russell. "The measurements show the brightest clouds ever observed with more variability and structure than expected, signifying a greater sensitivity to the environment in which the clouds form. They also show that the cloud season turns on and off like a “geophysical light bulb” going from no clouds to 100 percent cloud presence in a matter of days and vice versa at the end of the season." The bright "night-shining" clouds are seen by the spacecraft's instruments regularly, starting in late May and lasting until late August in the northern hemisphere and late November to late February in the southern hemisphere. The AIM satellite reports daily observations of the clouds at all longitudes and over a broad latitude range extending from 60 to 85 degrees. The clouds are made of ice crystals formed when water vapor condenses onto dust particles in the brutal cold of this region, at temperatures around minus 210 to minus 235 degrees Fahrenheit. One potential and plausible explanation for the changes observed is that temperatures where the clouds form are becoming colder with time due to carbon dioxide build-up resulting from human activities, Carbon dioxide increases near the Earth surface cause global warming, but at 50 miles altitude, the opposite occurs. Increasing methane in the atmosphere is another possible contributing factor because it reacts with oxygen to form water vapor that is needed to form the clouds. Both gases have been increasing in the atmosphere since the early 1900s. AIM is a NASA-funded SMall EXplorers (SMEX) mission managed by the Goddard Space Flight Center in Greenbelt, Md. The mission is led by Russell and the Project Data Center is managed at the HU Center for Atmospheric Sciences. HU undergraduate and graduate students in the fields of atmospheric science, computer science and engineering all work on the mission. The Laboratory for Atmospheric and Space Physics (LASP), University of Colorado, Boulder, and the Space Dynamics Laboratory, Utah State University built instruments. LASP also manages the AIM mission and controls satellite flight operations. GATS, Inc., Newport News, Va. led the ground data system development and leads the SOFIE instrument activities. Orbital Sciences Corporation, Dulles, Va., designed, manufac tured, and tested the AIM spacecraft, and provided the Pegasus launch vehicle. For more information on the AIM mission visit aim.hamptonu.edu. |
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