NASA launches latest Landsat mission
NASA's Landsat Data Continuity Mission (LDCM) spacecraft was successfully placed in orbit earlier this week. The mission marks the continuation of the 40-year Landsat Earth-observation program, which aids in the study of dynamic and ongoing changes to the planet.
The spacecraft was lifted into orbit by an Atlas V rocket, taking off from Vandenberg Air Force Base in California, before separating from the rocket 79 minutes after launch. The satellite, now in orbit at 680 km (422 miles), will reach its operational altitude of 705 km (438 miles) within two months, and will undergo a full three months of testing before becoming operational. It will then be renamed Landsat 8 and control will be transferred to NASA's mission partner, the Department of the Interior's U.S. Geological Survey (USGS), which will continue the Landsat program.
Landsat is the longest continuous data record of the Earth's surface and is a key tool in the study of climate change. NASA Administrator Charles Bolden commented on the significance of the program, stating that it “has led to the improvement of human and biodiversity health, energy and water management, urban planning, disaster recovery and agriculture monitoring – all resulting in incalculable benefits to the U.S. and world economy.”
The Landsat 8 will orbit every 99 minutes and image the entire planet every 16 days. It carries more advanced technology than its predecessors, including both the Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS). These instruments will make for improved reliability, sensitivity and data quality, while still maintaining compatibility with past Landsat data.
The OLI has fewer moving parts than the instruments it replaces and will capture visible, near infrared and shortwave infrared light. It will also observe high-altitude cirrus clouds, and monitor atmospheric aerosols and the water quality in lakes and coastal waters. The TIRS will monitor the temperature of the Earth's surface in two thermal bands, an improvement over the Landsat 7's single band instrument. These observations are used to analyze water consumption.
In 2008, NASA opened the doors to the Landsat data, allowing public access to its archives. That data was subsequently used in the creation of Google Earth Engine in 2012, a program that allows users to “zoom through” 13 years of Landsat imagery, providing a tangible insight into the changing face of the planet.