Landsat 7 systematically provides well-calibrated, multispectral, moderate resolution, substantially cloud-free, sun-lit digital images of the Earth's continental and coastal areas with global
... coverage on a seasonal basis. It covers the United States every 16 days. Operations were transferred to USGS on Fall 2000.
The Landsat Project is a joint initiative of the U.S. Geological Survey (USGS) and the NASA to gather Earth resource data using a series of satellites. NASA was responsible for developing and launching the spacecrafts, while the USGS is responsible for flight operations, maintenance, and management of all ground data reception, processing, archiving, product generation, and distribution.
The primary objective of the Landsat Project is to ensure a collection of consistently calibrated Earth imagery. Landsat's Global Survey Mission is to establish and execute a data acquisition strategy that ensures repetitive acquisition of observations over the Earth's land mass, coastal boundaries, and coral reefs; and to ensure the data acquired are of maximum utility in supporting the scientific objectives of monitoring changes in the Earth's land surface and associated environment.
Key Landsat 7 Facts [p. 176]
Joint with U.S. Geological Survey (USGS)
Heritage: Landsat 4, 5
Equatorial Crossing: 10:00 a.m. ± 15 mins
Altitude: 705 km ± 5 km (at the equator)
Inclination: 98.2° ± 0.15°
Period: 98.9 min
Repeat cycle: 16 days/233 orbits
Dimensions: 4 m high, 2.7 m diameter
Mass: 1982 kg
Power: 1550 W
Downlink: Three 150 Mbps wideband downlinks
Antennas: 3 gimbaled X-band, 2 omni S-band
Design Life: 5 years
Spacecraft: Lockheed Martin
ETM+: Raytheon Santa Barbara Remote Sensing
Data Archival, Processing, Ground Operations: USGS National Center for Earth
Resources Observation System (EROS) data center
Spacecraft and Sensor Maintenance: NASA GSFC
Calibration: EROS and GSFC
Type: Circular, sun-synchronous
[Summary provided by NASA.]