spase://SMWG/Observatory/NOAA/14

NOAA-J continued the third-generation operational, Polar Orbiting Environmental Satellite (POES) series operated by the National Environmental Satellite Service (NESS) of the National Oceanic and Atmospheric Administration (NOAA). NOAA-J continued the series of Advanced TIROS-N (ATN) spacecraft begun with the launch of NOAA-8 (NOAA-E) in 1983. NOAA-J was in a morning equator-crossing orbit and was intended to replace the NOAA 12 (NOAA-D) as the prime morning spacecraft. The goal of the NOAA/NESS polar orbiting program was to provide output products used in meteorological prediction and warning, oceanographic and hydrologic services, and space environment monitoring. The polar orbiting system complemented the NOAA/NESS geostationary meteorological satellite program (GOES). The NOAA-J Advanced TIROS-N spacecraft was based on the Defense Meteorological Satellite Program (DMSP) Block 5D spacecraft and was a modified version of the TIROS-N spacecraft (NOAA 1-5). The spacecraft structure consisted of four components: (1) the Reaction System Support (RSS); (2) the Equipment Support Module (ESM), which has been expanded from the TIROS-N design; (3) the Instrument Mounting Platform (IMP); and (4) the Solar Array (SA). All of the instruments were located on the ESM and the IMP. The spacecraft power was provided by a direct energy transfer system from the single solar array which was comprised of eight panels of solar cells. The power system for the ATN had been upgraded from the previous TIROS-N design. The in-orbit Attitude Determination and Control Subsystem (ADACS) provided three-axis pointing control by controlling torque in three mutually orthogonal momentum wheels with input from the Earth Sensor Assembly (ESA) for pitch, roll, and yaw updates. The ADACS controlled the spacecraft attitude so that orientation of the three axes was maintained to within +/- 0.2 degrees and pitch, roll, and yaw to within 0.1 degree. The ADACS consisted of the Earth Sensor Assembly (ESA), the Sun Sensor Assembly (SSA), four Reaction Wheel Assemblies (RWA), two roll/yaw coils (RYC), two pitch torquing coils (PTC), four gyros, and computer software for data processing. The ATN data handling subsystem, which was only slightly changed from the TIROS-N design to accomodate the additional instruments, consisted of the TIROS Information Processor (TIP) for low data rate instruments, the Manipulated Information Rate Processor (MIRP) for high data rate AVHRR, digital tape recorders (DTR), and a cross strap Unit (XSU). The NOAA-J instrument complement consisted of (1) the 5-channel Advanced Very High Resolution Radiometer/2 (AVHRR/2); (2) the TIROS Operational Vertical Sounder (TOVS), which consists of the Stratospheric Sounding Unit (SSU), the Microwave Sounding Unit (MSU) and the High Resolution Infrared Radiation Sounder (HIRS/2); (3) the Search and Rescue Satellite Aided Tracking System (SARSAT); (4) the Space Environment Monitor (SEM), which consisted of the Total Energy Detector (TED) and the Medium Energy Proton and Electron Detector (MEPED); (5) the French/CNES-provided ARGOS Data Collection and Location System (DCS); and (6) the Remote Atmospheric and Ionospheric Detection System (RAIDS), an experimental USAF test instrument. Most instruments became inoperational by February 2001. Only the omni-directional energetic ion detector remains operational as of January 2003.