Aqua is a joint project among the United States, Japan, and Brazil. The U.S. provided the spacecraft and the following four instruments: the Atmospheric Infrared Sounder (AIRS), the Clouds and the Earth's Radiant Energy System (CERES), the Moderate Resolution Imaging Spectroradiometer (MODIS), and the Advanced Microwave Sounding Unit (AMSU). Japan's National Space Development Agency (NASDA) provided the Advanced Microwave Scanning Radiometer for EOS (AMSR-E); and Brazil's Instituto Nacional de Pesquisas Espaciais (INPE, the Brazilian Institute for Space Research) provided the Humidity Sounder for Brazil (HSB).
Overall management of the Aqua mission is located at NASA's Goddard Space Flight Center in Greenbelt, Maryland. Goddard also provided the MODIS and AMSU instruments, managed the integration and testing of the spacecraft, is operating the spacecraft, and is receiving, processing, and (eventually) disseminating much of the science data through the EOS Data and Information System (EOSDIS). Goddard manages EOS for NASA's Earth Science Enterprise, headquartered in Washington, D.C. NASA's Jet Propulsion Laboratory, Pasadena, California, provided the AIRS instrument; and NASA's Langley Research Center, Hampton, Virginia, provided two CERES instruments, which will allow coincident measurements by one CERES scanning in lines perpendicular to the path of the satellite and by the other CERES scanning in lines at various angles with respect to the satellite's path. TRW constructed the Aqua spacecraft and carried out, at its facilities in Redondo Beach, California, the spacecraft's integration and testing.
Aqua was launched on May 4, 2002 at 2:55 a.m. PDT aboard a Delta II 7920-10L launch vehicle from the Western Test Range of Vandenberg Air Force Base, California. NASA's Kennedy Space Center, Florida, was responsible for the launch operations, including the Delta launch vehicle and the pre-launch integrated processing facility, the former under a contract with the Boeing Company and the latter under a contract with Spaceport Systems International. The U.S. Air Force was responsible for all range-related matters.
During launch, Aqua ascended to an altitude of 680 kilometers, after which it was boosted to its final orbital altitude of 705 kilometers (438 miles), through a series of six ascent burns, the final one on June 17, 2002. The spacecraft is positioned in a near-polar orbit around the Earth in synchronization with the Sun, with its path over the ground ascending across the equator at the same local time every day, approximately 1:30 p.m. Correspondingly, on the other side of its orbit, Aqua descends across the equator at approximately 1:30 a.m. The early afternoon observation time contrasts with the 10:30-10:45 a.m. equatorial crossing time (descending in this case) of the EOS Terra satellite, launched in December 1999. The two daytime crossing times account for why the Terra and Aqua satellites were originally named "EOS AM" and "EOS PM," respectively. The combination of morning and afternoon observations will allow studies concerning the diurnal variability of many of the parameters discussed above.
More information on EOS and the science related to it can be found at the EOS Project Science Office website at http://eospso.gsfc.nasa.gov and at the Earth Observatory website at http://earthobservatory.nasa.gov. Further information on Aqua can be found at http://aqua.nasa.gov and at http://aqua.gsfc.nasa.gov.