Landsat 6


Landsat 6, equipped with upgraded versions of the instruments on Landsat 5, was designed to carry forward the Landsat program. It was launched on October 5, 1993 with a Titan II launch vehicle, but failed to reach orbit. Landsat 6 omitted the Multi-Spectral Scanner found on its predecessors, but carried an Enhanced Thematic Mapper, which improved on the previous Thematic Mapper by adding a 15m-resolution panchromatic band.

Development

The Landsat 6 satellite was built by Martin Marietta Astro Space.

Design

Operations

The satellite was constructed from aluminum and used graphite struts. Landsat 6 had a hydrazine propulsion system. The spacecraft was powered by one solar array that had single-axis articulation and produced 1430 W. The power was stored in two NiCd batteries that had a capacity of 100 Ah. Data collected from the sensors was stored on tapes and transmitted to ground stations at 85 Mbit/s. The satellite was stabilized to 0.1 degrees in all three axes by using reaction wheels.

Sensors

The Enhanced Thematic Mapper was designed and manufactured by Santa Barbara Research Center.

Mission

Launch

Landsat 6 was launched aboard a Titan II launch vehicle from Vandenberg Air Force Base on October 5, 1993.

Operations

Even though Landsat 6 separated from the rocket at the appropriate time and place, the satellite failed to reach orbit. Since fuel could not reach the reaction engines, the satellite could not maintain attitude control during the apogee kick motor burn. This caused the satellite to tumble during the burn, resulting in a failure to orbit due to the wasted energy.
Martin Marietta and NOAA both convened review boards to investigate the failure. Both boards determined that Landsat 6 did not achieve orbit due to a ruptured hydrazine manifold, and recommended a task force investigate hydrazine feed systems that were more reliable.