On July 23rd, 1972, the first Landsat spacecraft launched into orbit. At the time, it was called "Earth Resources Technology Satellite," or ERTS, and was the first satellite to use a scanning spectrophotometer.
Previous satellites relied on film cameras (ejecting the exposed film to be caught by planes) or transmitted the signal from television cameras. The scanning sensor and its successor sensors on subsequent Landsat satellites revolutionized how we study our home planet.
Celebrating this anniversary, this video is a "greatest hits" montage of Landsat data. Throughout the decades, Landsat satellites have given us a detailed view of the changes to Earth's land surface. By collecting data in multiple wavelength regions, including thermal infrared wavelengths, the Landsat fleet has allowed us to study natural disasters, urban change, water quality and water usage, agriculture development, glaciers and ice sheets, and forest health.
NASA and the U.S. Department of the Interior through the U.S. Geological Survey (USGS) jointly manage Landsat, and the USGS preserves a more than 40-year archive of Landsat data that is freely available over the Internet.