Earth Observation Satellites
type: Concept

EP-TOMS
type: Concept
in scheme: platforms
definition: The Earth Probe TOMS (EP-TOMS) spacecraft was launched on July 2, 1996 from a Pegasus XL rocket and placed into a polar orbit with the following characteristics: Apogee Altitude : 515.2 km Perigee Altitude : 490.5 km Orbit Inclination : 97.432 deg. Period : 94.6 min The satellite was built by TRW for NASA's Goddard Space Flight Center. TOMS is part of NASA's Mission to Planet Earth a long term, coordinated research effort to study the Earth as a global environmental system. Using the unique perspective available from space, NASA will observe, monitor and assess large-scale environmental processes, focusing on climate change. MTPE satellite data, complemented by aircraft and ground data, will allow humans to better understand natural environmental changes and to distinguish natural changes from human induced changes. MTPE data, which NASA will distribute to researchers worldwide, is essential to humans making informed decisions about their environment. The goal of the Total Ozone Mapping Spectrometer (TOMS) Earth Probe mission (part of NASA's Mission To Planet Earth (MTPE) Phase I program) was to continue the high-resolution global mapping of total ozone on a daily basis (begun with the Nimbus 7 SBUV/TOMS) as well as to detect global ozone trends to verify depletion predicted by atmospheric chemistry models. The TOMS-Earth Probe (TOMS-EP), the first of a series of NASA Earth Probe missions, was one of three TOMS missions which included METEOR 3/TOMS2 (launched 1991) and ADEOS/TOMS (launched 1995). The TOMS-EP carried only one instrument: the Total Ozone Mapping Spectrometer (TOMS). The TOMS-EP spacecraft was based on the TRW/DSI Eagle bus developed under the USAF STEP program. The spacecraft was three-axis stabilized so that the TOMS instrument was nadir-pointed with about 0.5 degree control and about 0.1 degree knowledge from measured altitude data. The TOMS-EP spacecraft bus was designed to accomodate all of the TOMS instrument requirements to support a two-year li…