In July of 1972, NASA launched the first Landsat satellite into orbit around Earth. Since then, the spacecraft and its successors have transformed our understanding of Antarctica (and the rest of the planet, too). In the first year following the launch, Landsat’s images of the faraway continent showed “uncharted mountain ranges, vast ice movements and errors in maps as little as two years old,” according to an article published in Science News. William MacDonald of the U.S. Geological Survey, who had spent eight years mapping a part of West Antarctica, was “shocked” to learn of previously unknown peaks just 100 miles from McMurdo Station.
Landsat’s images weren’t the first overhead shots of Antarctica, but to this day the program provides researchers a reliable and repeating view of hard-to-reach corners of the planet. It was Landsat images that in November of 2014 first alerted scientists to a growing crack in the Larsen C ice shelf that, after lengthening by about 20 kilometers in less than nine months, threatened to break off a Delaware-sized chunk of the shelf. With thermal imagery from Landsat 8 along with data from the European Space Agency’s Sentinel-1 satellites, scientists sitting half a world away tracked the Larsen C crack to its final break, as described by Ashley Yeager.