NASA's Landsat 8 satellite acquired this image on Feb. 23, 2014. The avalanche debris appears light brown compared with the snow-covered surroundings. The sediment slid in a southeasterly direction, stretching across 7.4 kilometers (4.6 miles) and mixing with ice and snow in the process.
A whopping 68 million metric tons of material sliding down the flanks of Alaska's Mount La Perouse on Feb. 16, 2014, potentially makes this the largest-known natural landslide on Earth since 2010.
The slide was triggered by the collapse of a near-vertical mountain face at an elevation of 2,800 meters (9,200 feet), according to Colin Stark, a geophysicist at the Lamont-Doherty Earth Observatory at Columbia University.
The first visual confirmation that the slide had occurred came on Feb. 22, 2014, when helicopter pilot Drake Olson flew over and photographed the landslide debris. Landsat 8 passed over a day later, offering another view of the slide.
Image courtesy of NASA.
