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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
+ h# f) _9 T3 T4 k4 Y" e( n. ?, Feruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are
' Q5 L; C9 k- h0 aactive each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.
1 v4 w+ V) c- \9 T2 g: n$ q, [) dSome volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens,
( }& ]4 Z% i% D# c) Bwww2.tvboxnow.comerupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous . u3 v0 ?6 V0 P# V
and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions.
( k* Y. R% B3 G: I% f% @9 `$ hThey tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.4 R9 q2 Q9 b4 G- [* c

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Many of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above tvb now,tvbnow,bttvb; ?( N1 |$ n. A/ z5 F  n9 ^
of Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas
- V/ Z& {, U* twww2.tvboxnow.comtaken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash
: r6 c# M5 X* f; u# u0 E$ ?* b公仔箱論壇plume reached as high as 50,000 feet.www2.tvboxnow.com9 _4 T  p2 l" M5 E' u, F" o! r# T

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, Q; `3 _& P' D% r. ?0 z" g2 q, I# IAugustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra
5 n+ o# N! G0 D# G7 V) c4 N  S+ esatellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000
, y' y0 K* W  u' w' y4 A) x+ A: Otvb now,tvbnow,bttvbyears. 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
* f6 q, O4 [! ]* Hwww2.tvboxnow.comof Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet 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。* l- c4 k+ Z  e5 z0 d* \6 S$ d
ocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of
3 D* G/ d, r8 i  d$ \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 www2.tvboxnow.com  ?: r( O; `* j" t
in the Kuril Islands, northeast of Japan, on June 12, 2009. This was the volcano’s first eruption in 30 years.3 a. ^" j4 r" R% H' F5 X* }* f

1 a5 P3 G% L4 b! n" T* V2 A3 Y6 A6 wThe smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising
- I/ ~' P2 i, g; g/ `; ]tvb 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
) T1 I9 p! g& J3 K9 j6 }  ^' Das a pyroclastic flow.6 r) G! B9 ^  K" v2 F' T# C: i

8 W+ {9 L% F, NThis 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0 T+ ]/ N; M4 A5 C
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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.
' }( N, Z- x$ R" i5 x9 Q/ A! R$ _    * A shockwave from the eruption could have blown a hole in the cloud deck.
1 Q7 T, K. b5 m9 k' ptvb now,tvbnow,bttvb    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds.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。' v$ |4 p9 G3 F3 K6 j+ \! L

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Alaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet.
4 X( K1 r- W. T4 h  a* K* J) Lwww2.tvboxnow.comIt continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 whenTVBNOW 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。# V* W. ^% }7 T9 _$ t6 B5 P
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.com% [# o* X( f& h7 K# r) e- u

+ {2 T; o1 O! O& P! p1 k公仔箱論壇Redoubt is a 10,200-foot tall stratovolcano 100 miles southwest of Anchorage in the Aleutian Range, west of the Cook Inlet.www2.tvboxnow.com/ C: ]# e: v; s- Q- J: n- @

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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
" ~) R5 ~1 f0 a0 o. ltvb now,tvbnow,bttvb the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one
$ j5 C. C% K# G: K, I/ Ccaptured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in 8 }+ q5 o! a; X5 ]  J$ Z% Y3 q6 x
this picture are from forest fires ignited by lava.
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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
, r5 q  A% b. E' b& z6 m1 itvb now,tvbnow,bttvbalso be the oldest-known active volcano.
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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
- T  G0 b, ?) T: l0 ~8 b/ g* H0 xwww2.tvboxnow.comand 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。3 _1 |8 y3 y8 j6 T

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0 d& n. y2 q0 `$ hPopoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City. # j/ V  a$ N! O, B5 Z9 B
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 " Q7 q# p- u% _7 d9 c/ G, 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
+ M( o2 O' G# `3 w8 Y) v! f9 QTVBNOW 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.* ?& x5 ~6 M. D) P8 ~, T# ]& D

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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。9 n/ E. p8 g/ K1 a7 G; ^

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; w3 I* K) W8 @) L, 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。This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the 5 s: k# d! m; B' O
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# Q7 f- m- F5 W2 Y
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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
% K5 {% c8 l6 X) ^2 d3 Dflows 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 www2.tvboxnow.com* ^; W1 B" J3 j4 V5 z9 B0 R, w
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 公仔箱論壇! k* u" F1 F; i/ h9 n, D
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 N& K1 P9 C" ^! u. Bstationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.tvb now,tvbnow,bttvb1 W+ X% {+ u& }' p* ^2 X
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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. & I) m/ G8 M) K/ a0 K
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 公仔箱論壇2 L! B2 |* U' ]! c; e- v2 p9 a
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, 公仔箱論壇. C: a, S0 U. p5 ]6 T6 Y- n
causing avalanches of debris into the crater.

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