Volcanoes from outer space NASA's striking photographs of erupting volcanoes as seen from space. II
Aracar Volcano, Andes Mountains: Aracar volcano is one of
many volcanoes in the Andes Range that is located just east of the
Argentina-Chile border. Well-preserved lava flows are found at its base.
Prior to a report of ash columns from the summit in 1993, the volcano
was not known to be active and very little is known of the volcano's age
and history. Salars, the large whitish features are very common in the
arid Andes. The term salar is used exclusively of the saltwater wetlands
of the Puna (high Andes) and can describe not only salt lakes but also
temporary marshes, shallow lakes and lagoons, or simply salt crust. The
nearby Salar del Hombre Muerto is being put into mineral production. The
endeavor is expected to become one of Argentina's biggest mines,
producing up to 20,000 tons of lithium carbonate and lithium chloride
per year, to be extracted by pumping from the area's lithium-rich
saltbeds. This image was taken from the space shuttle on Feb. 20, 2000.
Image Credit: NASA/JPL/UCSD/JSC
Sarychev Volcano A fortuitous orbit of the International
Space Station allowed the astronauts this striking view of Sarychev
volcano (Russiaâs Kuril Islands, northeast of Japan) in an early stage
of eruption on June 12, 2009. Sarychev Peak is one of the most active
volcanoes in the Kuril Island chain and is located on the northwestern
end of Matua Island. Prior to June 12, the last explosive eruption had
occurred in 1989 with eruptions in 1986, 1976, 1954 and 1946 also
producing lava flows. Commercial airline flights were diverted from the
region to minimize the danger of engine failures from ash intake. This
detailed photograph is exciting to volcanologists because it captures
several phenomena that occur during the earliest stages of an explosive
volcanic eruption. The main column is one of a series of plumes that
rose above Matua Island (48.1 degrees north latitude and 153.2 degrees
east longitude) on June 12. The plume appears to be a combination of
brown ash and white steam. The vigorously rising plume gives the steam a
bubble-like appearance; the surrounding atmosphere has been shoved up
by the shock wave of the eruption. The smooth white cloud on top may be
water condensation that resulted from rapid rising and cooling of the
air mass above the ash column, and is probably a transient feature (the
eruption plume is starting to punch through). The structure also
indicates that little to no shearing winds were present at the time to
disrupt the plume. By contrast, a cloud
Mayon Volcano, The Phillipines: Tens of thousands of people
living within the danger zone of Mayon Volcano in the Philippines were
forced to evacuate to emergency shelters in mid-December 2009 as small
earthquakes, incandescent lava at the summit and minor ash falls
suggested a major eruption was on the way. On the evening of Dec. 14,
the local volcano observatory raised the alert level to Level 3, which
means "magma is close to the crater and hazardous explosive eruption is
imminent." This natural-color image of Mayon was captured on Dec. 15,
2009, by the Advanced Land Imager on NASA's Earth Observing-1 (EO-1)
satellite. A small plume of ash and steam is blowing west from the
summit. Dark-colored lava or debris flows from previous eruptions streak
the flanks of the mountain. A ravine on the southeast slope is occupied
by a particularly prominent lava or debris flow. The Phillipine Star
said on Dec. 22 that "ashfall blanketed at least three towns in Albay,
raising new health fears for thousands already bracing for an eruption
that could come at any time ... Health officials warned the tiny
particles could cause respiratory problems or skin diseases, and could
affect the thousands of people crammed into evacuation centers. Also on
Dec. 22, CNN reported that "tens of thousands of people have already
fled their homes. More than 9,000 families -- a total of 44,394 people
-- are being housed in evacuation camps after authorities raised the
alert status of the country's most active
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