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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 5.39.217.77:8898; x: ?6 q% r7 q3 ]( W
eruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are
, z* T& g5 a3 V. O8 \active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.  G& |  V" |+ {" X6 s& i6 ^0 F
Some volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens,
9 H2 N1 J- K: Ftvb now,tvbnow,bttvberupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous " T5 [0 M9 {1 n1 |- M9 [: q- h7 d3 s
and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions.
; b& J1 _- t$ C0 j* A公仔箱論壇They tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.
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& c% h# [. r8 I  ]1 L; T/ `Many of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above 公仔箱論壇9 j  r0 o. f! J1 h
of Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas
" p( W& ]8 _7 v0 I$ ^公仔箱論壇taken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash
: i3 `: U; a+ X5.39.217.77:8898plume reached as high as 50,000 feet.
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9 O# |- |6 }5 O2 G5 [$ W1 QAugustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra
( X$ f, N5 N& @" L5.39.217.77:8898satellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000 5.39.217.77:88987 u0 _* r" i0 R! v9 K
years. The island’s jagged edges were created by massive avalanches.
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8 ?  T0 L+ J3 Y5.39.217.77:8898Augustine lies in the Cook Inlet at the eastern end of the Aleutian trench which marks the northernmost portion of the Pacific Ring tvb now,tvbnow,bttvb6 X) w  m8 u3 n& F
of Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet
6 j8 T; x* W* a+ u: j# u/ K6 K6 Eocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of tvb now,tvbnow,bttvb; d) d- v1 e# l# H* D
the continental crust, creating magma that drives the volcanic eruptionsTVBNOW 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。8 H' B, i! H6 x+ r0 v3 l

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Astronauts aboard the International Space Station caught a lucky glimpse of the start of this eruption of Sarychev 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。; j, H& s$ d5 T- Y- u2 E
in the Kuril Islands, northeast of Japan, on June 12, 2009. This was the volcano’s first eruption in 30 years.- n5 N* `/ R4 o- {8 e

; M! L; ~* m2 Z% v! u9 jThe smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising 公仔箱論壇+ _- g3 V& D- [
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
) E- ]) a" B8 t' [5 U8 f# Y, etvb now,tvbnow,bttvbas 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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' |) ]7 y3 K: R& n0 i8 yTVBNOW 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。    * It could have nothing to do with the eruption and simply be caused by the contrast in temperatures between the ocean and the island.
7 q9 t  r4 ?* b/ O' R0 D    * A shockwave from the eruption could have blown a hole in the cloud deck.3 i. Y) u/ V. ^
    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds.
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Alaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet.
; f0 P! F8 z0 e  n0 |' ]7 n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 when
" l( I7 o. B9 M$ d8 Ltvb 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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Redoubt is a 10,200-foot tall stratovolcano 100 miles southwest of Anchorage in the Aleutian Range, west of the Cook Inlet., B- P0 Z0 Z% {- ]+ y# z
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$ o# ]  M9 w. y( D5 cTVBNOW 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 inTVBNOW 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. _6 q$ t4 C  M; W% a2 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 ; @/ ~5 {$ P+ f6 G" W) V! Z9 w
captured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in
/ h; B+ E" Z9 v- F9 x5.39.217.77:8898this picture are from forest fires ignited by lava.5.39.217.77:8898* e1 D9 n( k6 F2 \
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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 may5.39.217.77:8898: A/ ?0 o' V/ P- R2 g
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。" n( X- [) Z% P1 q- A: a3 A

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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
! a0 g2 P$ N$ l5 p7 ^4 c. kTVBNOW 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 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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Popoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City. 公仔箱論壇1 ~, H4 ?7 \7 m/ ?7 l  o) k" _
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
/ m- B7 r; q4 J+ y2 A- N" qmultiple 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
( S! _9 n% F; p& 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。of frequent activity. The plume reached heights of around 30,000 feet.5.39.217.77:8898! A0 l, Q3 D- O- W

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This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the
5 s' z2 F1 K' e# q. p7 kTVBNOW 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。west coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.4 k% W( P" V) t  L$ S. n; J
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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 5.39.217.77:88988 q; ?0 W1 W! w) _* H; e& `
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.5.39.217.77:88987 p- A( t9 [+ A9 N4 Y
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( P1 U6 J$ L, q) o& m3 RThis image of the Sierra Negra volcano in the Galapagos Islands was taken by NASA’s Terra satellite in 2006. Sierra Negra 5.39.217.77:8898+ r' k9 Z& R/ [  R3 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
; D1 R4 u( j% g9 {5 i% B! bformed 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
' k6 C- W/ \6 Y2 ?0 |5.39.217.77:8898stationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.6 L) H5 M& H# I9 U6 a8 Y
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+ _; D2 {) Y, s: u( z& 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。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. 公仔箱論壇3 U  G6 }5 Z# I+ {$ o
A 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 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。, K$ e& G, L# H1 {" N, Y) C
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, 5.39.217.77:8898: p$ _( S+ K9 e" ^( T9 M
causing avalanches of debris into the crater.

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