Landsat 5

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Landsat 5

Launch
Date	March 1, 1984
Vehicle	Delta 3920
Site	Vandenberg AFB
Orbit Characteristics
Reference system	WRS-2
Type	Sun-synchronous, near-polar
Altitude	705 km (438 mi)
Inclination	98.2°
Repeat cycle	16 days
Swath width	185 km (115 mi)
Equatorial crossing time	9:45 AM +/- 15 minutes

Landsat 5 is the fifth satellite of the Landsat program. It was launched on March 1st, 1984, with the primary goal of providing a global archive of satellite photos. The Landsat Program is managed by USGS, and data from Landsat 5 is collected and distributed from the USGS's Center for Earth Resources Observation and Science (EROS).

[edit] Solar Array Drive Anomaly

On November 26, 2005, the back-up solar array drive on Landsat 5 began exhibiting unusual behavior. The solar array drive maintains the proper pointing angle between the solar array (solar panels) and the sun. The rotation of the solar array drive became sporadic, and the solar array was not able to provide the power needed to charge the batteries. Maintaining power to the batteries is critical to sustain proper operation of the spacecraft. The primary solar array drive failed under similar circumstances in January 2005. As a result of this situation, imaging operations were suspended. [1] After a month-long investigation in December 2005 and testing in January 2006, new operating procedures were developed that will allow Landsat 5 to continue normal operations. [2]

[edit] Specifications

Landsat 5 has significantly exceeded its designed life expectancy, and has a maximum transmission bandwidth of 85 Mbit/s. It was deployed at an altitude of 705.3 km, a lower orbit than Landsat 4. It takes some 16 days to scan the entire Earth. The satellite is an identical copy of Landsat 4 and was originally intended as a backup - it therefore carries the same instruments, including the Thematic Mapper and Multi-Spectral Scanner. The Multi-Spectral Scanner was powered down in 1995.