English: The Batagaika Crater is the largest permafrost crater in the world and holds clues to prehistoric life on Earth. This massive landslide is located in Siberia. It formed in the 1960s when deforestation caused the permafrost to melt. The crater is about one kilometre wide and 90 metres deep, and has been growing year after year, as the warming climate thaws the frozen ground. Researchers believe the exposed ice and soil along the crater’s edges could hold up to 200,000 years of geological and biological history. This image, obtained by combining two Copernicus Sentinel-2 data products acquired roughly four years apart (04 September 2016 and 10 July 2020), shows the evolution of the crater over time. The areas of the crater coloured in red evidence the extension of the crater from 2016 to 2020. The Copernicus Sentinel-2 mission is a constellation of two twin satellites, Sentinel-2A and Sentinel-2B. The first satellite, Sentinel-2A has been launched in 2015, while the launch of Sentinel-2B took place in 2016. With a maximum revisit time of 5 days, the Sentinel-2 mission provides imagery on a full, free and open basis, allowing to regularly monitor the temporal evolution of environmental phenomena or emergency situations.