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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 www2.tvboxnow.com- c. |4 c0 m+ |! K; H* e
eruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are www2.tvboxnow.com# j: U/ h; Z' k$ G
active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.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。+ r9 b# e- j; `2 B  h  ?& j# w
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。7 b, ~) K0 S6 R# d" y8 H* q% _1 P
erupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous 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。* Z9 X1 x1 `% `" H1 R/ r3 [
and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions.
; ~/ F% I  O+ n- K6 a  Vwww2.tvboxnow.comThey tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.9 x- x0 Q; i: h8 y

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5 K7 ~8 |3 v/ J% cMany of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above
- r2 h# |9 W+ q; w/ M; Mtvb now,tvbnow,bttvbof Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas
2 g' M& q. p/ C3 K/ Itaken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash 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。: ~% g. X: ]! O! m% @9 }/ P
plume reached as high as 50,000 feet.
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9 S* R& L0 {4 w. |Augustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra 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。! @1 D- M  J& j+ R, X1 g( M( S
satellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000
/ S0 z2 k7 {) W* v9 ^( V公仔箱論壇years. 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
7 i* |1 h1 h, Eof Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet tvb now,tvbnow,bttvb% ]9 o6 p$ X8 ?  S8 O; t6 g
ocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of www2.tvboxnow.com8 x2 j) Q8 q1 i4 }
the continental crust, creating magma that drives the volcanic eruptions; B* E( e! ^8 D1 N9 @" j/ A
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( K) `! |+ Q; b+ p. ^; _& q+ vtvb now,tvbnow,bttvbAstronauts aboard the International Space Station caught a lucky glimpse of the start of this eruption of Sarychev Volcano
, z* ~0 k6 d, X) r, N* ^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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The smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising
- b, z. n, |; 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 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
. t) q2 X' u6 e( e( @* V" fTVBNOW 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 a pyroclastic flow.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。. Y( h! n* ~: L# L3 K
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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:公仔箱論壇9 N$ _  w+ {6 G8 U+ z1 I! b

; e$ W/ h# I" c  {. [7 {& lTVBNOW 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.
% `% F! h! ~5 D) Dtvb now,tvbnow,bttvb    * A shockwave from the eruption could have blown a hole in the cloud deck.
5 `! k- j# y- e" r. K9 p2 V, rwww2.tvboxnow.com    * 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.
! Y  W: [: F- M1 b7 _; W8 WIt continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 when
/ y$ s, k9 q4 c! ~' {( w) b公仔箱論壇 the ash reached heights of 27,000 feet. The volcano’s alert level is still “advisory,” and the aviation color code is yellow.www2.tvboxnow.com4 N9 A4 N9 n3 K  h9 x
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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.& z' S+ B3 p. r3 b

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9 u7 s3 R& r" L$ utvb now,tvbnow,bttvbMount 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。+ x0 i) e# I7 D
the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one 0 q* e6 V* E0 L, f% l9 W/ C* G
captured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in
* h" I( X+ I$ d* q5 G+ m* bthis picture are from forest fires ignited by lava.  z% I3 |* G: ]- }
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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 maytvb now,tvbnow,bttvb- C- W% b& h- s& [
also be the oldest-known active volcano.www2.tvboxnow.com+ F* j" B/ j% ?/ |. F+ ~8 p& e

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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 公仔箱論壇- D! [: N2 R& h" ]
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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( h) ?  l  D/ k6 B# _( APopoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City.
7 Q8 S. Y" u3 l. |3 z& f: h$ u3 |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
0 T5 l- r2 j, C* L3 P/ ^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 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。; Y/ E7 }7 d3 K3 X: X! m6 M
of frequent activity. The plume reached heights of around 30,000 feet.
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- ]6 X7 \' e1 C' {& o/ W; f; ftvb now,tvbnow,bttvbThis eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the
4 q8 ~  P0 P' _' l9 e" 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。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% L- d9 N$ _6 Y

  ?4 r2 p5 S6 `- s% aChaitén was last active more than 9,000 years ago. The violent 2008 eruption inundated the small coastal town of Chaitén with ash, pyroclastic
1 g  v( l+ h1 H9 n* o# D' ATVBNOW 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。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.
2 W7 d8 w7 o  |: k9 HTVBNOW 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。
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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 www2.tvboxnow.com, E# O! \* n2 U: k
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
5 d4 u# u; I9 l1 h  }& B公仔箱論壇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 公仔箱論壇  D) x) r8 ^. b6 ?4 m4 l
stationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.
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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.
( X3 O4 ?9 X& H- Z) _0 B2 Vwww2.tvboxnow.comA 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
# I2 \  ?$ |' B, a  L& Ntvb 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,
) O; Y3 w! c, B1 W5 _  ecausing avalanches of debris into the crater.

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