南极圈外的炽热心脏：卫星捕捉迈克尔山熔岩湖持续活动

Earth Observatory Science Earth Observatory A Bright Spot at Mount Michael Earth Earth Observatory Image of the Day EO Explorer Topics All Topics Atmosphere Land Heat & Radiation Life on Earth Human Dimensions Natural Events Oceans Remote Sensing Technology Snow & Ice Water More Content Collections Global Maps World of Change Articles Earth Matters Blog Blue Marble: Next Generation EO Kids Mission: Biomes About About Us Subscribe ? RSS Contact Us Search Mount Michael on Saunders Island, seen in this image acquired with the OLI (Operational Land Imager) on Landsat 8 on August 24, 2026, hosts a frequently active lava lake in its summit crater. NASA Earth Observatory/Michala Garrison Winter near the Antarctic Circle brings months of frozen darkness, when sea ice chokes ocean waters and many of its denizens hunker down to ride out the harsh conditions. But as winter began to release its icy grip, an uncommonly clear satellite image revealed that part of this remote realm was still very much awake, at least volcanically speaking. Mount Michael, the stratovolcano at the center of Saunders Island, rises above the ice-filled South Atlantic Ocean in this image, acquired with the OLI (Operational Land Imager) on the NASA-USGS Landsat 8 satellite on August 24, 2026. The natural-color image is overlaid with an infrared signal ( OLI bands 7-6-5), shown in red, revealing heat from the persistent lava lake in its summit crater. A puff of a volcanic plume hovering over the peak, along with darkened snow on its northern slopes, also suggests ongoing activity. Saunders Island is one of the South Sandwich Islands , a string of small volcanic peaks about 350 kilometers (220 miles) long that formed from the South American plate subducting beneath the tiny South Sandwich plate. Regular eruptions, including at Mount Michael, have occurred on these islands in recent centuries. Because of the volcanoes’ remoteness, scientists rely on satellite data to understand their activity. An analysis of thermal anomalies in Landsat, Sentinel, and ASTER (Advanced Spaceborne Thermal Emission and Reflection Radiometer) observations spanning 30 years led researchers to conclude that Mount Michael hosts a persistent lava lake in its summit crater. Only a handful of other volcanoes on Earth, including Kīlauea , Nyamulagira , and Erta Ale , are known to have similar, frequently active features. Thermal observations from the MODIS (Moderate Resolution Imaging Spectroradiometer) and VIIRS (Visible Infrared Imaging Radiometer Suite) instruments have also enabled long-term monitoring of Mount Michael. Data provided through MIROVA , a near-real-time volcanic hot spot detection system, indicate that low-intensity activity has been ongoing at the volcano for the past several years. Other observations from NASA’s Aura satellite show that emissions of sulfur dioxide and other gases are common at Mount Michael. Wave clouds form downwind of Saunders Island in this image acquired with the OLI (Operational Land Imager) on Landsat 9 on September 1, 2026. NASA Earth Observatory/Michala Garrison The cloud-free window over Mount Michael would close in short order. One week later, when Landsat 9 passed over the island, a more active atmosphere had returned. But the weather patterns interacted with the island to put on a spectacle of their own. The 843-meter-high (2,766-foot-high) peak jutting from the ocean disturbed passing winds to produce a series of wave clouds resembling the wake of a ship , a familiar phenomenon in this region. False-color imagery captured by NASA’s Aqua satellite indicates that a volcanic track caused by degassing sulfur dioxide was likely present as well. NASA Earth Observatory images by Michala Garrison, using Landsat data from the U.S. Geological Survey . Story by Lindsey Doermann. Downloads August 24, 2026 JPEG (4.27 MB) September 1, 2026 JPEG (1.14 MB) References & Resources Global Volcanism Program (2026) Saunders . Accessed September 4, 2026. Gray, D.M., et al. (2019) Evidence for a lava lake on Mt. Michael volcano, Saunders Island (South Sandwich Islands) from Landsat, Sentinel-2 and ASTER satellite imagery . Journal of Volcanology and Geothermal Research , 379, 60-71. MIROVA (2026) Michael . Accessed September 4, 2026. NASA Earth Observatory (2020, June 23) Volcanic Emissions Can Change Clouds . Accessed September 4, 2026. NASA Earth Observatory (2020, February 28) Sandwiched Wave Clouds . Accessed September 4, 2026. NASA Earth Observatory (2019, July 19) Lava Lake Discovered on Mount Michael . Accessed September 4, 2026. NASA Earthdata (2020, July 28) Sensing Remote Volcanoes . Accessed September 4, 2026. You may also be interested in: Stay up-to-date with the latest content from NASA as we explore the universe and discover more about our home planet. Ever Restless Mount Dukono Erupts 2 min read The volcano on Indonesia’s Halmahera Island routinely ejects ash, volcanic gases, and volcanic bombs. Article A Sea of Spinni