![]() ![]() The S/C and payload were developed under NASA/GSFC management/procurement responsibility (Landsat Project Scientist: D. 1)įollowing the loss of Landsat-6 during launch in 1993, Landsat-7 was placed on a fast track for launch in 1998, but was ultimately launched on 15 April 1999 (a one-year delay resulted from having to replace some faulty electronics inside the ETM+ sensor). The overall mission objective is to extend and improve upon the long-term record of medium-resolution multispectral imagery of the Earth's continental surfaces provided by the earlier Landsat satellites. The Landsat-7 satellite is part of NASA's ESE (Earth Science Enterprise) program, a joint venture of NASA and USGS (United States Geological Survey). Spacecraft Launch Mission Status Ground Segment References ![]() Overall, approximately 30% of the total image is missing in each downlinked picture. The function of the SLC was to compensate for the forward motion of the satellite during data acquisition, thus as a consequence of its failure, individual image scans overlap and leave large physical gaps near the edge of each picture. In May 2003 the Scan Line Corrector (SLC) on ETM+ failed. Orbit control and backup momentum is provided through a blow-down monopropellant hydrazine system with a single tank containing 122 kg of hydrazine. The satellite is powered by a four-panel silicon cell solar array and two nickel hydrogen batteries. Attitude control is provided by four reaction wheels and two torque rods, sensed with a static Earth sensor, two magnetometers and gyroscopes. With a mass of 2200 kg, the satellite features the three-axis stabilised Landsat-6 bus with an onboard recorder in solid state memory. The nominal descending equator crossing time is at 1000-1015, with a period of 99 minutes and repeat coverage of 16 days.īuilt by LMMS (Lockheed Martin Missiles and Space), the Landsat-7 spacecraft uses a very similar design to its predecessor, Landsat-6. Landsat-7 undergoes a sun-synchronous polar orbit at an altitude of 705 km with an inclination of 98.2°. The wide along-track coverage permits sufficient integration time for all cells in each scan sweep. This arrangement provides parallel coverage of 480 m along-track in one scan sweep (cross-track direction). The scanner contains two focal planes and detector line arrays oriented in the long-track direction. Data acquired using ETM+ has applications in land cover/change monitoring, agricultural forecasting, disaster response, urban planning, land and water resource management, and ecosystem monitoring.ĮTM+ images with a spatial resolution of 15 m for the PAN band, 30 m for VNIR/SWIR bands and 60 m for the TIR band, each covering a swath of 185 km. The addition of the PAN band, improved resolution and two 8-bit “gain” ranges in ETM+ have led to Landsat data progressing into use for global scale studies. ETM+ is a whiskbroom scanning radiometer capable of imaging in eight distinct bands including four visible and near-infrared (VNIR), two short wave infrared (SWIR), one thermal infrared (TIR) and one panchromatic (PAN) band. Landsat-7 features the Enhanced Thermal Mapper Plus (ETM+) developed by Raytheon SBRS (Santa Barbara Remote Sensing) which builds upon the Thermal Mapper (TM) onboard Landsat-4 & -5. Imaging multi-spectral radiometers (vis/IR) Glacier cover, Normalized Differential Vegetation Index (NDVI), Long-wave Earth surface emissivity, Cloud imagery, Active Fire Detection, Above Ground Biomass (AGB), Surface Water Extent, Fire temperature, Mineral Type, Fraction of Absorbed PAR (FAPAR), Cloud mask, Leaf Area Index (LAI), Fire fractional cover, Land surface temperature, Earth surface albedo, Short-wave Earth surface bi-directional reflectance, Vegetation type, Ocean imagery and water leaving spectral radiance, Land cover, Ocean chlorophyll concentration, Sea-ice cover, Glacier motion, Cloud cover, Snow cover, Sea-ice surface temperature, Iceberg fractional cover, Land surface imagery, Evapotranspiration, Permafrost Inland Waters, Multi-purpose imagery (ocean), Snow cover, edge and depth, Vegetation, Radiation budget, Albedo and reflectance, Cloud type, amount and cloud top temperature, Surface temperature (land), Multi-purpose imagery (land), Sea ice cover, edge and thickness, Ocean colour/biology ![]()
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