Volcanoes from outer space NASA's striking photographs of erupting volcanoes as seen from space.
The Cotopaxi Volcano: On
February 19, 2000, Space Shuttle Endeavour passed over the highly active
and dangerous volcanic zone of the Andes in Ecuador. Endeavour mapped
elevations on most of the Earthâs land surface during the Shuttle Radar
Topography Mission (SRTM). There have been more than 50 eruptions of Mt.
Cotopaxi alone since 1738. The digital elevation model acquired by
SRTM, with its resolution of 25 m x 25 m, is so rich in detail that you
can even make out an inner crater with a diameter of 120 m by 250 m
inside the outer crater (800 m x 650 m). Blue and green correspond to
the lowest elevations in the image, while beige, orange, red, and white
represent increasing elevations. Image Credit: NASA Earth Observatory
Santa Ana Volcano, El Salvador: On October 1, 2005, El
Salvadorâs Santa Ana Volcano, also known as the Ilamatepec Volcano,
erupted for the first time since 1904. The eruption reportedly shot out
car-sized lava rocks and a flood of boiling mud and water. This
false-color image was made from data collected by the Advanced
Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on NASAâs
Terra satellite on February 3, 2001, well before the 2005 eruption. The
Santa Ana volcano rises on the left side of the image, forming a large
flat-topped mound and sports several crescent-like craters at its summit
and a 20-kilometer-long system of fissures. A tiny blue spot in the
center of the inner-most crater is a crater lake, the likely source of
the boiling water flood. Behind Santa Ana is a large caldera lake inside
the Coatepeque Caldera, created when a series of volcanoes collapsed in
explosive eruptions between 57,000 and 72,000 years ago. In the
foreground is El Salvadorâs newest volcano, Izalco, which sprang up in
1770 and erupted frequently until 1966. The young volcano isnât covered
in vegetation (red in this image), but remains black with recent lava
flows. Santa Ana is the highest point in El Salvador. The volcano is
2,381 meters (7,812 feet) above sea level and is 65 kilometers (40
miles) west of the countryâs capital, San Salvador. Image Credit:
NASA/GSFC/METI/ERSDAC/JAROS/U.S./Japan ASTER Science Team/ Robert Simmon
Cleveland Volcano, Aleutian Islands: At 3:00 p.m. Alaska
Daylight Time on May 23, 2006, Flight Engineer Jeff Williams from
International Space Station (ISS) Expedition 13 contacted the Alaska
Volcano Observatory (AVO) to report that the Cleveland Volcano had
produced a plume of ash. Shortly after the activity began, he took this
photograph. This picture shows the ash plume moving west-southwest from
the volcano’s summit. A bank of fog (upper right) is a common feature
around the Aleutian Islands. The event proved to be short-lived; two
hours later, the plume had completely detached from the volcano. The AVO
reported that the ash cloud height could have been as high as 6,000
meters (20,000 feet) above sea level.
Cleveland Volcano, situated
on the western half of Chuginadak Island, is one of the most active of
the volcanoes in the Aleutian Islands, which extend west-southwest from
the Alaska mainland. It is a stratovolcano, composed of alternating
layers of hardened lava, compacted volcanic ash, and volcanic rocks.
Shiveluch Volcano: On March 29, 2007, the Shiveluch Volcano
on the Russian Federation's Kamchatka Peninsula erupted, sending an ash
cloud skyward roughly 9,750 meters (32,000 feet). Satellites often
capture images of volcanic ash plumes, but usually as the plumes are
blowing away. This image, however, is different. It shows the gray-brown
ash cloud suspended directly over the summit. At the time the Aqua
satellite passed overhead, the local air was still enough to let the ash
cloud hover. In this image, the bulbous cloud casts its shadow
northward over the icy landscape. Volcanic ash eruptions inject
particles into Earth's atmosphere; substantial eruptions of
light-reflecting particles can reduce temperatures and even affect
atmospheric circulation. Large eruptions may impact climate patterns for
years. A massive eruption of the Tambora Volcano in Indonesia in 1815,
for instance, earned 1816 the nickname "the year without a summer."
Shiveluch is a stratovolcano -- steep-sloped volcano composed of
alternating layers of solidified ash, hardened lava and volcanic rocks.
One of Kamchatka's largest volcanoes, it sports a summit reaching 3,283
meters (10,771 feet). Shiveluch is also one of the peninsula's most
active volcanoes, with an estimated 60 substantial eruptions in the past
10,000 years. Image credit: NASA/GSFC/MODIS Rapid Response Team
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