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Erupting Volcanoes on Earth as Seen From Space

One of the most violent but beautiful reminders that we live on ageologically restless planet are volcanic
' m# L4 C' W9 c- f# seruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are
/ g8 @% ?9 ~5 ?+ i$ a# e2 I6 ^公仔箱論壇active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.
  S. K/ X# g/ ?) S5.39.217.76Some volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens, tvb now,tvbnow,bttvb% s  t% L$ r3 w/ x* Q" y+ B4 J
erupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous 5.39.217.760 s. P3 z7 f' u. g1 R0 e+ g0 ]
and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions.
2 i. t2 `( B! a& D公仔箱論壇They tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.
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Many of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above 5.39.217.76( ]7 S: F: B3 h8 P# O5 p+ H
of Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas, [5 E7 s4 C: W+ _) x6 k1 T5 C) w- x! z
taken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash
7 {2 D$ d/ d" _' R9 Q4 C5 @公仔箱論壇plume reached as high as 50,000 feet.  \+ h+ |1 t/ m+ l; c
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Augustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra
' [! d% @+ a% y/ l; A) g1 O$ h, Htvb now,tvbnow,bttvbsatellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000
. m% J- W* H" O, ?7 R5 o  J* L0 H7 Pyears. The island’s jagged edges were created by massive avalanches.5.39.217.760 ]1 ?( C1 h: O, j! }

: m7 e0 O! w  Stvb now,tvbnow,bttvbAugustine lies in the Cook Inlet at the eastern end of the Aleutian trench which marks the northernmost portion of the Pacific Ring
6 T$ }  b0 t1 zTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。of Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet
( W# U8 R+ R9 S1 g' a+ S- j% L$ `ocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of . s4 f, O3 [) H( s* j2 f
the continental crust, creating magma that drives the volcanic eruptions公仔箱論壇+ ]* C6 Q. n$ S4 o2 u+ g6 X0 a

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Astronauts aboard the International Space Station caught a lucky glimpse of the start of this eruption of Sarychev Volcano 5.39.217.769 Z% ~$ U% a$ P, u# X( Z* Y( ^' @
in the Kuril Islands, northeast of Japan, on June 12, 2009. This was the volcano’s first eruption in 30 years.
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7 n! b" @1 \' n, AThe smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising
0 `; a5 d4 p' u5 P2 B4 U2 j/ ^* L5.39.217.76and cooling of the air above. In contrast, a dark gray cloud of ash near the ground is probably an avalanche of hot ash and rock known 5.39.217.76: w# q7 T! N4 B
as a pyroclastic flow.
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% D2 K8 W# H) t9 ~5 a; E( h( t! V' Z. i公仔箱論壇This photo sparked a debate among scientists about what caused the hole in the clouds above the eruption. Three possible options came up:
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    * It could have nothing to do with the eruption and simply be caused by the contrast in temperatures between the ocean and the island.tvb now,tvbnow,bttvb+ O' h* x4 t# g, _" y* P. Y( x- j
    * A shockwave from the eruption could have blown a hole in the cloud deck.
2 _/ e3 v! [- o. h+ TTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds." r" ?6 F- Z% K7 q7 ]  |7 ?
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2 Z+ Z8 {3 g, d* U公仔箱論壇Alaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet.
/ n7 ~1 v: a8 x# c1 w- l, l5.39.217.76It continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 when
9 F% P; U% g! a$ Jtvb now,tvbnow,bttvb the ash reached heights of 27,000 feet. The volcano’s alert level is still “advisory,” and the aviation color code is yellow.
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2 Q' t% }* n) `& NRedoubt is a 10,200-foot tall stratovolcano 100 miles southwest of Anchorage in the Aleutian Range, west of the Cook Inlet.
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Mount Etna is the second tallest volcano in Europe, at almost 11,000 feet. It is one of the most active volcanoes in
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captured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in
1 Q/ c5 ~" j4 e* {1 ^* X, z6 _公仔箱論壇this picture are from forest fires ignited by lava.
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+ G+ W0 H* A7 @$ V, _5.39.217.76Etna is a stratovolcano located on the island of Sicily. It is one of the most studied volcanoes in the world and. at 500,000 years old, it maytvb now,tvbnow,bttvb& K1 J) }/ t- R3 f$ a; k0 j; h
also be the oldest-known active volcano.5.39.217.763 o' Y1 ^8 Q( k) K6 w
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A NASA astronaut spotted this eruption of Cleveland Volcano from the International Space Station in 2006. The volcano is 5,700 feet high TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。, D% L% e) |2 l8 H' D1 u$ E) Q# i
and claimed the only known eruption-related death in Alaska’s Aleutian Islands in 1944. Its symmetrical, cone shape is typical of stratovolcanoes.TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。6 t% \$ ^: V6 @/ m6 b' A

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; l2 r$ h) \1 s4 x, }2 OTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。Popoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City.
$ V3 L( j6 S( N  R公仔箱論壇The second highest peak in Mexico at 17,800 feet, this glacier-covered stratovolcano has erupted at least 20 times in the last 500 years and has caused TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。: U3 N  n* R% P  D5 a8 w7 R
multiple evacuations of the city. This eruption in 2001 was caught by astronauts on the International Space Station, near the end of a seven-year period
8 P# S+ L5 |8 o9 y+ ]8 J* hof frequent activity. The plume reached heights of around 30,000 feet.tvb now,tvbnow,bttvb: R+ b# e( K4 `" n. m

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" R& \+ F4 F! i, d) O5.39.217.76This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the 公仔箱論壇; D% w2 F* x$ B7 R* i! d5 D. T
west coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.5.39.217.76' l$ Y+ u7 S3 u* @

! s( ]8 l3 n; H' ]5 B! F$ @Chaitén was last active more than 9,000 years ago. The violent 2008 eruption inundated the small coastal town of Chaitén with ash, pyroclastic TVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。- i- Z& L# {' U2 i% @: {' l
flows and volcanic mudflows called lahars. The caldera is relatively small at less than two miles wide, and sits on the flank of the larger Michinmahuida volcano.
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This image of the Sierra Negra volcano in the Galapagos Islands was taken by NASA’s Terra satellite in 2006. Sierra Negra tvb now,tvbnow,bttvb: w5 d; ]6 A2 }$ d
is a shield volcano, which are made mostly of previous lava flows and tend to be broad and gently sloping. The Galapagos are part of an island chain 3 q' p  s2 ?2 h) m
formed by a hot spot where a plume of hot mantle rises up and melts the base of the ocean crust. As the Pacific plate moves over the relatively
! `) ~& N6 V: _) k# Y6 @9 O7 Wstationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.
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, x) M! v0 l1 ^* m5.39.217.76NASA’s Terra satellite snapped this image of Shiveluch volcano erupting on Russia’s Kamchatka peninsula at the edge of the Pacific Ring of Fire in 2004.
6 P( C# D, T6 w: J9 Z+ E0 dtvb now,tvbnow,bttvbA lava dome had been growing in the volcano’s crater, followed by intermittent eruptions that lasted weeks. Shiveluch is a 10,400-foot-high stratovolcano
8 f2 p/ a8 N8 G4 Q, W7 Xtvb now,tvbnow,bttvbthat is at least 60,000 years old and has been erupting fairly often for the past 10 years. Its dome has collapsed multiple times, most recently in 1964,
& s! H0 V- o% A$ E# i8 kcausing avalanches of debris into the crater.

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