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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 tvb now,tvbnow,bttvb# E) u% i* F& N$ q* U9 X- c" V) k* ^
eruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are
& F8 z1 c4 Y, S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.
/ v$ C/ C" s' otvb now,tvbnow,bttvbSome volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens,
; V% G" Q6 A( A5 C6 \# L4 V* V公仔箱論壇erupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous
/ G, i7 F2 B( c# G* bTVBNOW 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。and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions.
! ~8 s: ]- K, mTVBNOW 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。They tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.公仔箱論壇9 e& v( [2 }- a- ]+ @) ?, }9 M

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) Q5 x6 t# V: Fos.tvboxnow.comMany of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above
* P9 C4 o' u5 m- W! c9 Eof Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas
' `5 a: o+ ]. H" X! C公仔箱論壇taken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash
$ i- N# q) R! M' z) i( 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。plume reached as high as 50,000 feet.7 `2 K1 ~/ o- M3 U$ p5 }, G

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Augustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra 0 S# U/ M% G- i. f7 k' u
satellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000
, I# ?- C# y4 u8 i- S: Q. ~' u( b* uyears. The island’s jagged edges were created by massive avalanches.
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Augustine 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+ b4 t. ?0 H; o' o* J, F8 S
of Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet
. m/ R: i- u) S$ _# L7 Z, H9 oocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of : E: q3 t' C5 d% p% U0 f6 z
the continental crust, creating magma that drives the volcanic eruptionstvb now,tvbnow,bttvb, o( [8 k! m: l" j! y

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) B" ]# ?9 R9 v, ^3 Etvb now,tvbnow,bttvbAstronauts aboard the International Space Station caught a lucky glimpse of the start of this eruption of Sarychev Volcano tvb now,tvbnow,bttvb  ?1 D2 c( b3 r, f
in the Kuril Islands, northeast of Japan, on June 12, 2009. This was the volcano’s first eruption in 30 years.6 P5 l) t  ]% F4 R! s! W; S

  k* P' f3 U+ X7 q% r6 pThe smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising & b2 l9 c4 ~3 |, t" j
and 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 os.tvboxnow.com; t% Z( y2 i; a% e
as a pyroclastic flow.
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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.
6 {4 q% |4 D4 W% k) ~公仔箱論壇    * A shockwave from the eruption could have blown a hole in the cloud deck.os.tvboxnow.com$ ^* A& u% u0 o! i. T: v
    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds.
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: m2 w9 v3 Z5 Y4 z4 d+ `公仔箱論壇Alaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet. / ]2 d8 M; v% |; z5 h, J( e
It continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 whenos.tvboxnow.com& t5 @' G1 D# j& U0 @
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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3 u2 o! j; }/ n7 |$ c5 i8 Atvb now,tvbnow,bttvbRedoubt 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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4 J! n# M  z" Y% C4 C! [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。Mount Etna is the second tallest volcano in Europe, at almost 11,000 feet. It is one of the most active volcanoes in* k: L9 O) N+ \1 H6 Q
the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one
! @6 M4 |% i1 D7 U& {' acaptured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in 5 v0 Y( N' [2 G3 Y: [
this picture are from forest fires ignited by lava.tvb now,tvbnow,bttvb: A$ r$ d0 }* D- x
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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 may9 {+ J. v1 c% U9 x
also be the oldest-known active 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。7 e6 x' M: j8 Q, a$ `$ {8 d

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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
0 z- ?' q! z$ A: ]5 P, L% E, n2 T* P  ]and claimed the only known eruption-related death in Alaska’s Aleutian Islands in 1944. Its symmetrical, cone shape is typical of stratovolcanoes.os.tvboxnow.com6 I. @, c' R+ D: L! |; r' s

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Popoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City.
( B6 p! l+ g; |tvb now,tvbnow,bttvbThe 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。2 Q# J# z7 q/ y6 U7 A& v
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
6 a8 m4 u/ B" N5 ?of frequent activity. The plume reached heights of around 30,000 feet.5 }( W2 r( e0 u  D! ~3 P: [
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This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the tvb now,tvbnow,bttvb) w$ C% F2 \  p  q2 H) r
west coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.tvb now,tvbnow,bttvb, O$ Q0 D9 ~+ s& u, [" d
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Chaitén was last active more than 9,000 years ago. The violent 2008 eruption inundated the small coastal town of Chaitén with ash, pyroclastic
; x; U2 \  c8 K! F3 ^6 X% G公仔箱論壇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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6 o8 r' I* M+ nThis image of the Sierra Negra volcano in the Galapagos Islands was taken by NASA’s Terra satellite in 2006. Sierra Negra
3 U* F" P; t( W' r( p) J$ e, ]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 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。7 D# r. t) I+ ^
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
! _1 m. ?3 ]9 N! Hstationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.os.tvboxnow.com# t$ Z3 c7 g, |4 f8 a/ ?

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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.
4 q$ O" [8 k7 g6 A6 d+ bA 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
* F) ]5 ~+ G0 S公仔箱論壇that 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,
: k8 h) \7 _/ G+ D' R6 C  gos.tvboxnow.comcausing avalanches of debris into the crater.

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