Landsat 7
Landsat 7 is the latest satellite of the Landsat program. It was launched on April 15th, 1999. The primary goal of Lansat 7 is to refresh the global archive of satellite photos, providing up-to-date and cloud free images. Although the Landsat Program is managed by NASA, data from Landsat 7 is collected and distributed by the USGS.
Landsat 7 was designed to last for five years, and has the capcity to collect and trasmit up to 532 images per day. It is in a polar, sun-synchronous orbit, meaning it scans across the entire earth's surface. It takes 233 orbits, or 16 days, to do so. The satellite weighs 1973 kg, is 404 cm long, and 274 cm in diameter. Unlike its predecessors, Landsat 7 has a solid state memory of 378 gigabits (roughly 100 images). The main instrument on board Landsat 7 is the Enhanced Thematic Mapper Plus (ETM+). It's main features are:
A false color IR image of Washington DC, taken by Landsat 7
Satellite Specifications
External Links