Satellite Images of Chaiten Volcano
A collection of NASA images from Earth Observatory documenting Chaiten's 2008-2009 eruption.
On May 2, 2008, Chile’s Chaitén Volcano erupted, sending plumes some 30 kilometers (18.6 miles) skyward, and blanketing some nearby areas in as much as 1.5 meters (5 feet) of volcanic ash. In the week that followed the initial eruption, local authorities established an evacuation zone with a radius of 50 kilometers (31 miles) around the volcano, warning holdouts that they would be evacuated by force, if necessary.
On February 21, 2000, the Enhanced Thematic Mapper on NASA’s Landsat satellite captured the volcano in a state of calm. In this image, the volcano’s caldera appears as a pale brown crater inside an ocean of lush green vegetation that covers the mountainous region. To the southwest is the nearby coastal town with the same name as the volcano. The satellite’s view is obscured only by the occasional cloud.
The tranquility of the volcano apparent in this image has been the norm throughout recorded human history. The May 2008 eruption was a surprise—Chaitén’s first eruption in more than 9,000 years. Even when a volcano has been active in recent history, the surrounding areas often provide good reasons to settle, including fertile soils and milder climates arising from high altitudes (at least in the tropics).
NASA image created by Robert Simmon, using Landsat data provided by the University of Maryland’s Global Land Cover Facility. Caption by Michon Scott.
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After more than 9,000 years of silence, Chaitén Volcano in southern Chile erupted on May 2, 2008. The plume of ash and steam rose 10.7 to 16.8 kilometers (35,000 to 55,000 feet) into the atmosphere, reported the Smithsonian’s Global Volcanism Program. According to news reports issued by the AFP news service, ash blanketed the town of Chaitén, 10 kilometers away, forcing the town’s 4,000 people to evacuate by boat.
On May 3, ash and steam continued to billow from the volcano. The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite captured this photo-like image of a long, cloud-like plume flowing southeast from the volcano’s summit on May 3 at 10:35 a.m. local time (14:35 UTC). The plume rises high over the Andes Mountains, drifts across Argentina, and dissipates over the Atlantic Ocean. Ash closed schools, roads, and an airport in Argentina, hundreds of kilometers away from the volcano, said AFP.
Radiocarbon dating of the last lava flow from Chaitén Volcano suggests that the volcano last erupted in 7420 BC, plus or minus 75 years, says the Global Volcanism Program. The volcano has a history of explosive eruptions with pyroclastic flows associated with dome collapse. During an eruption, some volcanoes build a dome of lava. Eventually, hot blocks of lava break away from the dome, triggering a fast-moving avalanche of hot volcanic ash, gas, and lava, called a pyroclastic flow. As of May 5, ash continued to rise from the volcano, but no pyroclastic flows had been reported.
The large image provided above is at MODIS’ maximum resolution of 250 meters per pixel. The image is available in additional resolutions from the MODIS Rapid Response System.
NASA images courtesy Jeff Schmaltz, MODIS Rapid Response Team at NASA GSFC. Caption by Holli Riebeek.
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Chile’s Chaitén Volcano had been dormant for more than 9,000 years when it erupted in May 2008. In the months that followed, the volcano remained active, releasing plumes of steam and volcanic ash, coating local vegetation, clogging waterways, and inundating the nearby town of the same name. On January 19, 2009, an explosive dome collapse occurred at the volcano, according to a bulletin from the Volcanism Blog. A thick plume of ash and steam blew from the volcano’s summit approximately 70 kilometers (38 nautical miles) to the north-northeast, according to the U.S. Air Force Weather Agency.
On January 19, 2009, the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite captured an image of Chaitén Volcano. Two versions of the image appear here: a close-up view of the caldera (top) and a view of the surrounding area (bottom). These false-color images include visible and infrared light. Vegetation is red, bare (possibly ash-covered) ground is brown, and water is deep blue. The plume from the volcano appears off-white, and it is thick enough to completely hide the land surface below.
South and southeast of the volcano, the land surface varies in color from gray to brown, with only isolated patches of red. Close to the volcano, the darker brown colors probably indicate areas coated with volcanic ash or places where the vegetation was killed by earlier ash falls. Farther to the east and south, however, the light gray-brown color probably indicates naturally bare, alpine areas. Glaciers (light blue patches) are scattered among the valleys at the right side of the wide-area image. The meandering waterway between the volcanic summit and the coastal town of Chaitén is Río Blanco, and this river carried numerous lahars—volcanic mudflows—into the town after the May 2008 eruption. Despite repeated inundations, the town’s grid-like layout remains visible.
NASA image created by Jesse Allen, using data provided courtesy of NASA/GSFC/METI/ERSDAC/JAROS, and U.S./Japan ASTER Science Team. Caption by Michon Scott.
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Perhaps one of nature’s greatest displays of power is an erupting volcano. Towering clouds of ash and steam, intense heat, fast-moving landslides, and flowing lava are a just a few of the many life-threatening hazards of a volcanic eruption. The power and danger are at once frightening and fascinating. Satellites provide a detailed and comprehensive view of an eruption from the safety of hundreds of kilometers away. These images, from the Advanced Land Imager on the EO-1 satellite, show the ongoing eruption of Chile’s Chaitén Volcano.
The top image shows the volcano and its surroundings in photo-like true color. The Chaitén Volcano is a relatively small, tan mound near the top of the image. A white plume, likely composed of steam and possibly ash, rises from the volcano. Gray-tan ash blankets the snow on the peak of the neighboring Minchinmávida Volcano and the land between the two peaks.
The lower image includes both infrared and visible light. Chaitén’s peak glows red from the heat of the eruption. The snow beneath the ash on Minchinmávida is bright blue. Plant-covered land is green, and cooler clouds have a slight blue tint.
The EO-1 satellite captured these images on March 6, 2009. Chaitén began to erupt unexpectedly on May 2, 2008, after some nine thousand years of quiet. The eruption forced the evacuation of the nearby town of Chaitén and covered hundreds of kilometers of farmland in ash. Though the volcano continued to emit clouds of ash, a few of Chaitén’s citizens had returned in early 2009 when the volcano erupted again on February 19. According to the Smithsonian Global Volcanism Program, part of the lava dome collapsed, causing lateral explosions, block-and-ash flows, and pyroclastic flows (a fast-moving avalanche of hot ash, volcanic rocks, and gas). One flow came within five kilometers of the town. The volcano was clearly still active two weeks later when EO-1 observed it.
NASA image created by Jesse Allen, using EO-1 ALI data provided courtesy of the NASA EO-1 Team. Caption by Holli Riebeek.
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