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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 公仔箱論壇! D/ t% R2 g5 Y! y. Z
eruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are
0 _: {( @* G) g" Q8 g: D" |active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.5.39.217.765 A" t& D0 n. \% ?$ ]- e
Some volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens, 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 Q0 g/ i9 X- _- O: _
erupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous
6 d+ M5 j& ~$ ]0 z, v  o3 S8 N9 L3 yand explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions. ! ]6 n+ ?; C8 U
They tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.公仔箱論壇) ?6 n0 o5 C/ L! L# {9 v! f, _

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Many of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above ) z& b5 X4 [0 G7 S
of Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas5.39.217.76. s) p" x- f8 S4 A
taken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash
, [# s( F9 C  Y: `. G( C* @: Jtvb now,tvbnow,bttvbplume reached as high as 50,000 feet.公仔箱論壇5 ^7 v% `. C% @& n8 Z

3 y2 a( w5 H! g2 RTVBNOW 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。
" m& {' X: A4 B$ J3 g8 }4 y( JTVBNOW 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。
; o( l4 ^$ L, _& b! uTVBNOW 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。Augustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra
. W! n( j5 f, z4 z/ _9 ]! ~5 vTVBNOW 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。satellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000
; i8 l) k8 @# L2 d1 _+ A$ Q! Otvb now,tvbnow,bttvbyears. The island’s jagged edges were created by massive avalanches.
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: W8 v# N' G1 x7 \+ mAugustine lies in the Cook Inlet at the eastern end of the Aleutian trench which marks the northernmost portion of the Pacific Ring 公仔箱論壇4 \8 T* G# C4 O9 k) s+ \% x
of Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet
: \2 `  e7 [9 _- ^3 t7 UTVBNOW 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。ocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of
3 J/ K7 x4 p& V2 eTVBNOW 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。the continental crust, creating magma that drives the volcanic eruptions
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Astronauts aboard the International Space Station caught a lucky glimpse of the start of this eruption of Sarychev Volcano 公仔箱論壇- s' U! C" p( O+ ~3 u
in the Kuril Islands, northeast of Japan, on June 12, 2009. This was the volcano’s first eruption in 30 years.tvb now,tvbnow,bttvb( V, G& m4 K* C
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The smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising
6 [% m$ i# j- \# l9 J% w: P  Ltvb now,tvbnow,bttvband 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 5.39.217.760 \  a! k. C' ?8 i
as a pyroclastic flow.5.39.217.76. a* m# p- t- R' G9 R- M  P& h+ k$ f

7 k# K/ h* q- x& T7 l! @) i- _5.39.217.76This 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.
4 u9 C6 H% A; f! Y2 d; iTVBNOW 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。    * A shockwave from the eruption could have blown a hole in the cloud deck.
5 _. I) X, X" a( A3 I7 q  R9 P5.39.217.76    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds.tvb now,tvbnow,bttvb8 p; N6 g$ @( A# e
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, W% Y5 v% O/ `  w. Y( atvb now,tvbnow,bttvbAlaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet.
8 F2 d, [7 w  D5 R3 V公仔箱論壇It continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 when5 ~  O7 O. }' P
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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Redoubt is a 10,200-foot tall stratovolcano 100 miles southwest of Anchorage in the Aleutian Range, west of the Cook Inlet.公仔箱論壇9 ]% r, h  G/ e1 X( o# q
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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# t1 A9 i: {. z' C
the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one 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。4 l8 G3 ?' H, O- a& Q
captured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in
7 h! ~+ @& n3 {5.39.217.76this picture are from forest fires ignited by lava.5.39.217.765 l" x5 E2 i+ f! s  a6 L0 L& ~
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Etna 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 may
, a3 P- z( Y0 t, @+ {8 L9 E% }also be the oldest-known active volcano.
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( _9 T. G: w6 ~" E  ntvb now,tvbnow,bttvbA NASA astronaut spotted this eruption of Cleveland Volcano from the International Space Station in 2006. The volcano is 5,700 feet high # A( P/ y# N& J
and claimed the only known eruption-related death in Alaska’s Aleutian Islands in 1944. Its symmetrical, cone shape is typical of stratovolcanoes.
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. Q, E* b7 ]# s% f5.39.217.76Popoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City.
' t4 p6 u" U& m1 Y6 P7 ~1 Y/ iThe 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
" d5 R4 y! r# r+ c5.39.217.76multiple 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 9 I! F: A- x/ ~! G! a9 R
of frequent activity. The plume reached heights of around 30,000 feet.* A4 u5 X. q: C+ r4 Q$ {6 A+ [
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8 Z  X/ k  C- ^* A: JTVBNOW 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。This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the 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。- @* j" @, A: M0 C4 p# t
west coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.公仔箱論壇1 S6 b) R2 D: O$ S( X" {. Q

, j8 M& T' l* m  z) F' ctvb now,tvbnow,bttvbChaitén was last active more than 9,000 years ago. The violent 2008 eruption inundated the small coastal town of Chaitén with ash, pyroclastic
! I6 P$ W$ J8 _) \  `" I4 i" ctvb now,tvbnow,bttvbflows 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.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。2 g0 z& l# E; t9 m/ t
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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
9 F# @( [; t+ m! Y; T% I; [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
1 b" g' w; ~0 b; hformed 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 & F8 Q; [. B" }  Y& h- H
stationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.2 P1 Y6 Z& v3 S% U/ \- q

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NASA’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.
* g. r* e7 A% Z4 J( \0 d4 ~tvb 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
* o; T3 \' p/ o- h+ s* y8 |tvb 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, + `2 P7 ~0 t$ B2 D. b
causing avalanches of debris into the crater.

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