Landsat 9 is the latest satellite in the Landsat series and is currently in orbit collecting data on Earth’s land surface. Launched on 27 September 2021, Landsat 9 is set to orbit the Earth for the next 10+ years. Landsat-9 is the continuation of the Landsat satellite family stretching back almost 50 years, and for the past six years also flying in unison with the European Union’s Sentinel-2 satellites.
Compared to its predecessors, Landsat 9 and the Sentinels can better measure changes to the globe’s land surface at a scale where human and natural causes of land use change can be distinguished. Apart from monitoring surface water dynamics applications of the satellites include weekly tropical deforestation alerts, water quality monitoring, and crop condition reports, among others.
The end goal of the Landsat series is to provide decision makers with unbiased and scientific data on a range of environmental issues by monitoring the health and state of the Earth. With the launch of Landsat 9, NASA plans to decommission Landsat 7 which has been in orbit around the earth since 1999. Landsat 8 continues to operate, and together the two satellites will collect images of the entire globe every 8 days – an observation frequency which becomes even higher when adding Sentinel-2 with a 5-day revisit time.