English: The Nevados de Chillán volcano is one of the Chile’s most active volcanoes. Explosions with ash plumes rising to three kilometres above the summit area were observed from late January through early June 2020. Some of the larger explosions produced pyroclastic flows. In June 2020, the Chilean National Geology and Mining Service (SERNAGEOMIN) reported the growth of a lava dome inside the crater: as consequence, a slow lava flow started its expansion along the northern flank, reaching about 600 m in length at the end of October 2020. This image, acquired by one of the Copernicus Sentinel-2 satellites on 25 October 2020, provides a cloud-free view of the Nevados de Chillán crater, with two active hot spots and the lava flow (in cooling) clearly visible on the northern flank of the volcano. The Copernicus Sentinel-2 mission (Sentinel-2A and Sentinel-2B) plays an important role in volcanic activity monitoring: the high spatial resolution and an average revisit time of five days enable to monitor different volcanic processes and improve hot-spot detection.