As U.S. television audiences watched enraptured over a decade of careful planning and technological advances culminate in Neil Armstrong and Buzz Aldrin’s first steps on the moon, the Hughes aeronautics company research center in Santa Barbara, California began work on a new scanning tool that would bring about the next series of satellite launches: not to reach the moon, but to study the earth, and its ever-shifting, ever-flowing landmasses.

On this day, July 23 in 1972, the Earth Resources Technology Satellite, the first one ever with the express purpose to study and monitor the earth’s land, was launched from Vandenberg Air Force Base in California.

The Landsat 1 carried on board a sophisticated camera system called the Return Beam Vidicon (RBV), built by the Radio Corporation of America, and the Hughes-developed experimental Multispectral Scanner (MSS). The MSS proved the more useful of the two, and its recordings of meteorological and land conditions proved enormously useful to everyone from forestry officials to oceanographers. The satellite even found a previously uncharted tiny uninhabited island off the coast of Canada, which was named Landsat Island in the satellite’s honor.