WASHINGTON — The U.S. Geological Survey (USGS) transmitted its final command to the aged Landsat 5 satellite June 5, officially ending a mission that launched more than 29 years ago, the USGS announced June 19.

Landsat 5, recognized by Guinness World Records as the longest-operating Earth observation satellite, collected more than 2.5 million images of Earth, recording events including the 1986 Chernobyl nuclear disaster and the 2004 tsunami that devastated parts of southeastern Asia. Launched from Vandenberg Air Force Base, Calif., on March 1, 1984, Landsat 5 was designed for a three-year mission.

The USGS had been preparing to decommission the NASA-built satellite for nearly a year, and a November component failure forced the agency to put its plan into action. Starting Jan. 15, some nine days after Landsat 5 beamed its last image to USGS’s EROS Data Center in Sioux Falls, S.D., controllers began lowering the satellite’s altitude from its 750-kilometer operating orbit to a disposal orbit.

With Landsat 5’s fuel exhausted, controllers on June 5 issued commands to shut off all of its moving parts. The final command shut down the satellite’s transmitter.

The satellite is expected to re-enter the atmosphere in approximately 21 years, USGS spokesman Jon Campbell said.

Currently the USGS relies on the Landsat 8 satellite, launched Feb. 11 and formally commissioned May 30, for medium-resolution imagery of Earth’s land masses. It also has the Landsat 7 satellite, which has been hobbled by a sensor glitch that occurred not long after its 1999 launch.

Warren Ferster is the Editor-in-Chief of SpaceNews and is responsible for all the news and editorial coverage in the weekly newspaper, the spacenews.com Web site and variety of specialty publications such as show dailies. He manages a staff of seven reporters...