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Earth from Space – Eruption in the Red Sea

Satellite image of a volcanic eruption in the Zubair Group

NASA Earth Observing-1 (EO-1) satellite image of a volcanic eruption in the Zubair Group of islands in the Red Sea.

AN ERUPTION OCCURRED in the Red Sea in December 2011. According to news reports, fishermen witnessed lava fountains reaching up to 30 metres tall on December 19.

The Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra and Aqua satellites observed plumes on December 20 and December 22. Meanwhile, the Ozone Monitoring Instrument (OMI) on NASA’s Aura satellite detected elevated levels of sulphur dioxide, further indicating an eruption.

The activity in the Red Sea included more than an eruption. By December 23, 2011, what looked like a new island had appeared.

The Advanced Land Imager (ALI) on NASA’s Earth Observing-1 (EO-1) satellite captured these high-resolution, natural-colour images on December 23, 2011 (above), and October 24, 2007 (below).

Satellite image of Zubair Group islands

A satellite image of the same region, taken in 2007, shows no sign of the new volcanic island.

The image from December 2011 shows an apparent island where there had previously been an unbroken water surface. A thick plume rises from the island, dark near the bottom and light near the top, perhaps a mixture of volcanic ash and water vapour.

The volcanic activity occurred along the Zubair Group, a collection of small islands off the west coast of Yemen. Running in a roughly northwest-southeast line, the islands poke above the sea surface, rising from a shield volcano.

This region is part of the Red Sea Rift where the African and Arabian tectonic plates pull apart and new ocean crust regularly forms.

Wider satellite image of a volcanic eruption in the Zubair Group

This wider view shows more of the islands in the Zubair Group.

Close up satellite image of a volcanic eruption in the Zubair Group

And this close up gives a better view of the new island and the huge plume of smoke and steam.

NASA Earth Observatory image created by Jesse Allen, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Text adapted from information issued by Michon Scott.

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Russian volcano seen from space

Kuril Island volcanoes seen from space

Kuril Island volcanoes seen from space.

IN THIS IMAGE TAKEN by an astronaut aboard the International Space station, snow cover highlights the calderas and volcanic cones that form the northern and southern ends of Onekotan Island, part of the Russian Federation in the western Pacific Ocean.

Calderas are depressions formed when a volcano empties its magma chamber in an explosive eruption and then the overlaying material collapses into the evacuated space.

The northern end of the island (image right) is dominated by the Nemo Peak volcano, which began forming within an older caldera approximately 9,500 years ago. The last recorded eruption at Nemo Peak occurred in the early 18th century.

The southern end of the island was formed by the 7.5-kilometre-wide Tao-Rusyr Caldera. The caldera is filled by Kal’tsevoe Lake and Krenitzyn Peak, a volcano that has only erupted once in recorded history (in 1952).

Extending between northeastern Japan and the Kamchatka Peninsula of Russian, the Kurils are an island arc located along the Pacific “Ring of Fire.” Island arcs form along an active boundary between two tectonic plates, where one plate is being driven beneath the other (subduction). Magma generated by the subduction process feeds volcanoes—which eventually form volcanic islands over the subduction boundary.

See the full-size image (1MB) here.

Adapted from information issued by William L. Stefanov, NASA-JSC. Image by ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Centre.

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Searching for stinky planets

Artist's conception of a volcanic moon

Artist's conception of an extremely volcanic moon orbiting a gas giant planet in another star system.

  • Exoplanet atmospheres can now be analysed
  • Super-volcanoes could emit copious sulphur gases
  • Could be detected by next generation space telescope

Astronomers think they’ve found a way to detect the presence of sulphur-spewing volcanoes on planets orbiting stars beyond our Solar System.

Volcanoes display the awesome power of Nature like few other events. Earlier this year, ash from an Icelandic volcano disrupted air travel throughout much of northern Europe. Yet this recent eruption pales next to the fury of Jupiter’s moon Io, the most volcanic body in our Solar System.

And now that astronomers are finding rocky worlds orbiting distant stars, they’re asking the next logical questions: Do any of those worlds have volcanoes? And if so, could we detect them?

Work by theorists at the Harvard-Smithsonian Centre for Astrophysics suggests that the answer to the latter is a qualified “Yes.”

“You would need something truly earthshaking, an eruption that dumped a lot of gases into the [planet’s] atmosphere,” said Smithsonian astronomer Lisa Kaltenegger.

“Using the James Webb Space Telescope, we could spot an eruption 10 to 100 times the size of Pinatubo for the closest stars,” she added.

Jupiter's moon Io

Jupiter's moon Io is the most volcanically active body in the Solar System.

Astronomers are decades away from being able to take images of the surface of alien worlds, or “exoplanets”. However, in a few cases they’ve been able to detect the atmospheres of “gas giant” planets known as “hot Jupiters.”

A volcanic eruption would emit fumes and various gases, so volcanic activity on a rocky exoplanet might leave a telltale chemical signature in the planet’s atmosphere.

Sniffing out volcanoes on other world

To work out which volcanic gases might be detectable, Kaltenegger and her Harvard colleagues, Wade Henning and Dimitar Sasselov, developed a computer model for eruptions on an Earth-like exoplanet based on the present-day Earth.

They found that sulphur dioxide from a very large, explosive eruption is potentially measurable because a lot is produced and it is slow to wash out of the air.

Sulphur dioxide has a sharp, acrid smell, sometimes described as similar to the smell of a just lit match.

To look for volcanic sulphur dioxide, astronomers would rely on a technique known as a secondary eclipse, when the exoplanet goes behind its star as seen from Earth.

By collecting light from the star and planet, then subtracting the light from the star alone (while the planet is hidden in the eclipse), astronomers are left with the light spectrum from just the planet. They can examine that spectrum for signs of particular chemical molecules.

Artist's concept of an exoplanet orbiting a star

Artist's concept of an exoplanet orbiting a star. By measuring the light both when the planet is in front of and behind (eclipse) by the star, astronomers can isolate the planet's light and gain information about it's atmospheric gases.

“Our first sniffs of volcanoes from an alien Earth might be pretty rank!” Kaltenegger said. “Seeing a volcanic eruption on an exoplanet will show us similarities or differences among rocky worlds.”

Catching one in the act

The 1991 eruption of Mount Pinatubo in the Philippines spewed about 17 million tonnes of sulphur dioxide into the stratosphere—a layer of air 10 to 45 miles above Earth’s surface. The largest volcanic eruption in recorded history, the 1815 Tambora event, was about 10 times more powerful.

Such gigantic eruptions are infrequent, so astronomers would have to monitor many rocky, Earth-sized exoplanets for years to catch one in the act. However, if alien worlds are more volcanically active than Earth, success might be more likely.

“A Tambora-sized eruption doesn’t happen often here, but could be more common on a younger planet, or a strongly tidally active planet—analogous to Io,” said Henning. “Once you detected one eruption, you could keep watch for further ones, to learn if frequent eruptions are common on other planets.”

Due to its proximity, a hypothetical Earth or super-Earth orbiting the nearby star Alpha Centauri would offer a best-case scenario for a sun-like star.

But any Earth-like planet less than 30 light-years away could show faint signs of volcanism when studied with the James Webb Space Telescope, the next generation optical telescope due to be launched in the middle of this decade.

Adapted from information issued by CfA / Wade Henning / NASA.

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Space spin-offs

This video shows how NASA technology designed to check for toxic gases on the launch pad, is now being pressed into service to help monitor dangerous volcanoes around the world.

Adapted from information issued by NASA / Sandra Joseph and Kevin O’Connell.

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Island of volcanoes

Satellite image of volcanoes on Paramushir Island.

A collection of volcanoes on Paramushir Island in the Kuril Island chain.

The Kuril Island chain is built from a line of volcanoes, an “island arc”, which extends from Russia’s Kamchatka Peninsula to northern Japan.

Island arcs form along an active boundary between two tectonic plates, with one being driven beneath the other (subduction). Magma generated by subduction feeds volcanoes—and eventually volcanic islands—over the subduction boundary.

Paramushir Island in the northern Kurils is an example of a large island built by several volcanoes over geologic time. This astronaut photograph shows the southern end of Paramushir Island after a snowfall. The western slopes of the mountains are brightly illuminated, while the eastern slopes are in shadow.

Four major volcanic centres create this part of the island. Fuss Peak (image centre left) is an isolated stratovolcano connected to the main island via an isthmus. Fuss Peak last erupted in 1854.

The southern tip of the island is occupied by the Karpinsky Group of three volcanic centres. A minor eruption of ash following an earthquake occurred on this part of the island in 1952.

The Lomonosov Group to the northeast (image centre) includes four cinder cones and a lava dome that produced several lava flows in the past, but there have been no eruptions from the Lomonosov Group in recorded history.

The most recent volcanic activity on Paramushir Island occurred in 2008 at the Chikurachki cone located along the northern coastline of the island at image top centre. The summit of this volcano (1,816 metres, or 5,958 feet, above sea level) is the highest on Paramushir Island.

Much of the Sea of Okhotsk visible in the image is covered with low clouds that often form around the islands in the Kuril chain. The clouds are generated by moisture-laden air passing over the cool sea/ocean water, and they typically wrap around the volcanic islands.

See the full-size image here (1MB, will open in a new window).

Astronaut photograph provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Centre. Text adapted from information issued by William L. Stefanov, NASA-JSC.

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Volcano at the end of the world

Volcán Villarrica

Volcán Villarrica, an active volcano near the southern tip of South America.

Near the southern tip of South America, a trio of volcanoes lines up perpendicular to the Andes Mountains. The most active is the westernmost, Volcán Villarrica, pictured in this photo-like image from the Advanced Land Imager on NASA’s Earth Observing-1 (EO-1) satellite on May 15, 2010.

The 2,582-metre-high (9,357-foot) stratovolcano is mantled by a 30-square-kilometre (10-square-mile) glacier field, most of it amassed south and east of the summit in a basin made by a caldera depression. To the east and northeast, the glacier is covered by ash and other volcanic debris, giving it a rumpled, brown look.

The western slopes are streaked with innumerable grey-brown gullies, the paths of lava and mudflows (lahars). Beyond the reach of ash and debris deposits, the volcano is surrounded by forests; the area is a national park.

See the full-size image here (4MB, new window).

The biggest recent eruption was in the early 1970s; lava flows melted glaciers and generated lahars that spread at speeds of 30–40 kilometres per hour (20-30 mph) toward Lago Villarrica (visible to the northwest in large image) and southwest toward Lago Calafquéen (lower left).

NASA Earth Observatory image by Jesse Allen and Robert Simmon, using EO-1 ALI data provided courtesy of the NASA EO-1 team. Text adapted from information issued by Rebecca Lindsey.

Colombia’s ice-covered volcano

The Nevado del Ruiz volcano in Colombia

The Nevado del Ruiz volcano in Colombia, erupted in 1985, killing at least 23,000 people.

The large Nevado del Ruiz volcano in Colombia is featured in this image photographed by an Expedition 23 crewmember on the International Space Station. Nevado del Ruiz is located approximately 140 kilometres to the northwest of the capital city of Bogota and covers an area of over 200 square kilometres.

Nevado del Ruiz is a stratovolcano — a type of volcano built from successive layers of lava, ash, and pyroclastic flow deposits — formed by magma generated above the boundary between the subducting Nazca and overriding South American tectonic plates.

The historical record of eruptions extends back to 1570, but the most damaging eruption in recent times took place in 1985. On November 13, 1985, an explosive eruption at the Arenas Crater (centre) melted ice and snow at the summit of the volcano. This lead to the formation of mudflows (or lahars) that swept tens of kilometres down river valleys along the volcano’s flanks, resulting in the deaths of at least 23,000 people. Most of the fatalities occurred in the town of Armero, which was completely inundated by lahars.

Eruptive activity at Nevado del Ruiz may also have occurred in 1994, but this is not confirmed.

The volcano’s summit and upper flanks are covered by several glaciers that appear as a white mass surrounding the one-kilometre-wide Arenas Crater; melt water from these glaciers has incised the grey to tan ash and pyroclastic flow deposits mantling the lower slopes. A well-defined lava flow is visible at lower right.

This photograph was taken at approximately 7:45a.m. local time when the Sun was still fairly low above the horizon, leading to shadowing to the west of topographic high points.

Adapted from information issued by NASA.

Volcano Alley

This astronaut photograph shows four stratovolcanoes in El Salvador.

This astronaut photograph shows four stratovolcanoes in El Salvador.

A line of active and quiescent volcanoes known to geologists as the Central American Volcanic Arc marks the Pacific coastline of much of Central America.

The volcanoes result from the upward movement of magma generated along the subduction zone between the Cocos and Caribbean tectonic plates. Frequent earthquakes also occur along the plate boundary.

This astronaut photograph includes four stratovolcanoes—a type of volcano common in active subduction zones—in El Salvador, near the midpoint of the Central American Volcanic Arc.

While all of the volcanoes shown here have been active during the Holocene Epoch (from about 10,000 years ago to the present), only the 2,130-metre- (6,990-foot-) high San Miguel (also known as Chaparrastique) has been active during historical times. The most recent activity of San Miguel was a minor gas and ash emission in 2002. The stratovolcano’s steep cone shape and well-developed summit crater are evident, along with dark lava flows.

Immediately to the northwest, the truncated summit of Chinameca Volcano (also known as El Pacayal) is marked by a two-kilometre-wide caldera. The caldera formed when a powerful eruption emptied the volcano’s magma chamber, causing the chamber’s roof to collapse. Like its neighbour San Miguel, Chinameca’s slopes host coffee plantations.

Moving to the west, the eroded cone of El Tigre Volcano is visible. El Tigre formed during the Pleistocene Epoch (1.8 million to about 10,000 years ago), and it is likely the oldest of the stratovolcanoes in the image.

Usulután Volcano is directly southwest of El Tigre. While the flanks of Usulután have been dissected by streams, the mountain still retains a summit crater that is breached on the eastern side. Several urban areas—recognisable as light grey to white regions contrasting with green vegetation and tan fallow agricultural fields—are located in the vicinity of these volcanoes, including the town of Usulután (lower left) and Santiago de Mara (upper left).

Astronaut photograph provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Centre. Text adapted from information issued by William L. Stefanov, NASA-JSC.

World’s highest volcano

Satellite image of Llullaillaco Volcano.

South America’s Llullaillaco Volcano is the world's highest historically active volcano.

The summit of South America’s Llullaillaco Volcano has an elevation of 6,739 metres (22,110 feet) above sea level, making it the highest historically active volcano in the world.

The current stratovolcano—a cone-shaped volcano built from successive layers of thick lava flows and eruption products like ash and rock fragments—is built on top of an older stratovolcano.

The last explosive eruption of the volcano, based on historical records, occurred in 1877.

This detailed astronaut photograph of Llullaillaco illustrates an interesting volcanic feature known as a coulée (image top right). Coulées are formed from highly viscous, thick lavas that flow onto a steep surface.

As they flow slowly downwards, the top of the flow cools and forms a series of parallel ridges orientated at 90 degrees to the direction of flow (somewhat similar in appearance to the pleats of an accordion).

The sides of the flow can also cool faster than the centre, leading to the formation of wall-like structures known as flow levees (image centre).

Llullaillaco is also a well-known archaeological site—the mummified remains of three Inca children, ritually sacrificed 500 years ago, were discovered on the summit in 1999.

Image provided by the ISS Crew Earth Observations experiment and Image Science & Analysis Laboratory, Johnson Space Centre. Text adapted from information issued by William L. Stefanov.

Russia’s twin volcanoes

Klyuchevskaya and Bezymianny volcanoes on Russia's Kamchatka Peninsula.

A satellite image of the Klyuchevskaya and Bezymianny volcanoes erupting on Russia's Kamchatka Peninsula.

Neighbouring volcanoes on Russia’s Kamchatka Peninsula acted up at the same time in mid-February 2010. Klyuchevskaya Volcano in the north and Bezymianny Volcano in the south both sent plumes skyward over a snowy landscape. The Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASA’s Terra satellite captured this false-colour image on February 13, 2010.

Low-angled sunlight illuminates the southern slopes of Kamchatka’s rugged landscape, as well as the southern sides of both volcanic plumes. The plumes’ light colour suggests that, of the visible material in each plume, steam predominates over volcanic ash. Both plumes cast shadows toward the northwest.

Reaching a height of 4,835 metres (15,860 feet), Klyuchevskaya (also Kliuchevskoi) Volcano is both the tallest and most active volcano on Kamchatka. It is a stratovolcano—a steep-sloped, conical structure composed of alternating layers of solidified ash, hardened lava, and rock fragments ejected by earlier eruptions.

On February 11, 2010, the Kamchatka Volcanic Eruption Response Team (KVERT) reported above-background seismic activity at Klyuchevskaya Volcano, including gas and/or steam plumes reaching 6 kilometres (20,000 feet) above sea level, lava flows, and Strombolian eruptions—intermittent explosions or fountains of rock—roughly 300 metres (1,000 feet) above the volcano’s summit.

Dwarfed by its neighbour, Bezymianny reaches 2,882 metres (9,455 feet) above sea level. Compared to the volcano immediately to the north, it releases a smaller, thinner plume. Like Klyuchevskaya, Bezymianny is also a stratovolcano.

On February 11, KVERT reported that Bezymianny was releasing plumes that could affect low-flying aircraft, and it might have experienced a moderate explosive event on February 5-6, 2010. More significant seismic activity at Klyuchevskaya, however, obscured data from Bezymianny.

Kamchatka lies along the Pacific Ring of Fire—a seismically active area encircling the Pacific Ocean. Both Klyuchevskaya and Bezymianny were intermittently active in late 2009 and early 2010.

NASA Earth Observatory image created by Jesse Allen, using data provided courtesy of NASA / GSFC / METI / ERSDAC / JAROS, and the US / Japan ASTER Science Team. Text adapted from information issued by Michon Scott.