| astronautix.com | DMSP Block 5D-2 |
DMSP 5D-2 is the military's sixth generation of weather satellites. The DMSP 5D-2 satellites operate in two satellite constellations to provide world-wide meteorological, oceanographic and solar-terrestrial physics measurements on a twice-daily basis. The visible and infrared sensors collect images of global cloud distribution across a 3,000 km swath during both daytime and night time conditions. The coverage of the microwave imager and sounders are one-half the visible and infrared sensors coverage, covering the polar regions above 60 deg on a twice-daily basis but the equatorial region on a daily basis. The space environmental sensors record along-track plasma densities, velocities, composition and drifts. Spacecraft: Based on GE Tiros bus.3-axis stabilised using reaction wheels, torque rods to 0.01 deg. Hydrazine propulsion system for orbit insertion, nitrogen propulsion system for stationkeeping. Star sensors and gyros provide 0.01 deg. knowledge. Earth sensor, sun sensor carried as backup. Data stored on tape recorder. Solar array generates 900 W (BOL). NiCd batteries with 30 AHr capacity. S-band communications: 5 W RF, 5 MHz bandwidth, omni antennas. Controlled from Offutt AFB, Nebraska with terminals at Loring AFB, Maine, Fairchild AFB, Washington, and AFRTS Hawaii. Payload: Typical payload mass is approximately 110 kg, and includes Operational Linescan System (OLS) - visible/infrared imager, SSM/T - atmospheric sounder producing cloud temperature profiles, SSM/I - microwave imager measuring ice coverage, precipitation areas and intensities, cloud water content, ocean surface wind speeds, SSB/X2 - gamma and x-ray spectrometer, SSJ/4 - measures proton and electron densities, SSM - magnetometer.
Financial/Operational:
R&D cost for DMSP 5D-2 was $ 7.6 million. The first joined 5 earlier generation DMSP's still operating in orbit. Launch of 8 more was planned through 2006.
Design Life: 3 years . Total Length: 3.4 m. Maximum Diameter: 1.2 m. Total Mass: 770 kg.
Defense Meteorological Satellite Program.
Defense Meteorological Satellite Program.
Defense Meteorological Satellite Program.
Defense Meteorological Satellite Program.
Defense Meteorological Satellite Program; broken nozzle prevented from reaching desired orbit.
Defense Meteorological Satellite Program.
Defense Meteorological Satellite Program.