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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
4 `( ~" H6 [- y$ P+ i' S7 H. o: {tvb now,tvbnow,bttvberuptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are
6 _  k: `0 b" O" U5.39.217.76active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.公仔箱論壇0 @8 J0 R& W: T$ C; K* T
Some volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens,
4 n( g6 @$ Y- Qerupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous
: j) o1 [( M- ]# W5.39.217.76and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions.
7 i! c# {6 v* q* `; i* l) z5.39.217.76They tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.
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! B* P3 v- h& D1 S/ E( H) 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。
( B: z5 _5 ?3 o5 s+ `9 TTVBNOW 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。Many of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above
5 N" [. v8 R% f) q+ V: @8 K$ }: Ytvb now,tvbnow,bttvbof Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas. \+ O  r: o$ I
taken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash
8 ?& Z4 a+ I' Z$ i/ n7 e6 N5 Dplume reached as high as 50,000 feet.( C! v9 B8 c1 J9 Y" C4 x0 C
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& q3 a* ?3 y9 g- ]4 Ktvb now,tvbnow,bttvbAugustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra 公仔箱論壇; b8 U% ?' x+ ?( x: r
satellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000
9 T( M$ K$ f' vyears. The island’s jagged edges were created by massive avalanches.
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* F! n* T, K8 XAugustine lies in the Cook Inlet at the eastern end of the Aleutian trench which marks the northernmost portion of the Pacific Ring
! y! i' d- p, U$ Z6 m5.39.217.76of Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet
; n$ ~$ A- _( V$ k) C, @; e2 f" [公仔箱論壇ocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of
+ I8 Q; T. P9 E9 Y% N6 \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。the continental crust, creating magma that drives the volcanic eruptions+ x! E9 q8 s9 ?- k

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! v$ I  a9 k; u# m3 B5 {9 @+ B+ nAstronauts 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。, I% L; W) L8 e; e, P* ?
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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/ p4 B/ A) n! r, \% c5.39.217.76The smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising
' v( G) F6 N/ r( xTVBNOW 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 : y; y9 z1 J8 M, @4 S: t2 \
as a pyroclastic flow.2 [: w0 f7 @! Y

/ X) }0 p0 s" J. ?$ h* |+ C# \公仔箱論壇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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$ z1 a$ n0 `( P$ Y, e    * It could have nothing to do with the eruption and simply be caused by the contrast in temperatures between the ocean and the island.
& v! k& d7 C- ~' z( 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。    * A shockwave from the eruption could have blown a hole in the cloud deck.公仔箱論壇# \/ V3 E5 g, X# {+ y; D5 E
    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds.
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- O5 y, Z/ M) h; q公仔箱論壇Alaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet.
, l' M1 L4 N0 s. z' gtvb now,tvbnow,bttvbIt continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 when
) s! |, [7 p! {5.39.217.76 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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! P$ |3 ?* l5 Ktvb 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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Mount Etna is the second tallest volcano in Europe, at almost 11,000 feet. It is one of the most active volcanoes in9 t2 X( r) ?9 ]" _* c2 G$ R$ L
the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one
" J6 l1 v2 }( s6 B$ s5 ?" o% j公仔箱論壇captured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in 公仔箱論壇4 J3 D- b5 j6 l7 d! r
this picture are from forest fires ignited by lava.
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. t- Q2 R6 e3 m& ]" A/ E' f. wTVBNOW 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。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
# i3 z* B- f8 `8 Galso be the oldest-known active volcano.5.39.217.765 n+ h: K: J& P1 h

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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
' w: B3 Q: [1 ]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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* }) b# X6 V" O6 p# f2 J# c4 ^2 v公仔箱論壇Popoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City.
6 h/ b* D; m7 N7 S' g* g! Y5.39.217.76The 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。+ N% f( |( \9 y
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
0 h2 X* L3 R% p0 x3 _tvb now,tvbnow,bttvbof frequent activity. The plume reached heights of around 30,000 feet.
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% p( {6 b2 X6 B( U( [0 rtvb now,tvbnow,bttvb
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& Y3 q; M8 ]& d; y0 d; `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。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。- _# c# B: c' ?# a
west coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.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。  O; v4 q) q; A

' W6 r' r; ~/ w  MChaitén was last active more than 9,000 years ago. The violent 2008 eruption inundated the small coastal town of Chaitén with ash, pyroclastic
- M9 J- z3 p, P8 K' ^0 |5 d' j# Pflows 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.公仔箱論壇5 H, S' m) w  ]

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# A7 G- I% b, E% E5.39.217.76This image of the Sierra Negra volcano in the Galapagos Islands was taken by NASA’s Terra satellite in 2006. Sierra Negra 公仔箱論壇4 N  G( l. z5 ]3 j% b9 r
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5 I- z0 p7 ]/ l- J8 A* i0 S
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 9 Z2 h$ e& T; o0 J
stationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.公仔箱論壇& D# q, N4 C- p( ?4 v

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% t  L( \1 l) t3 N8 p0 D; X. `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. 0 J2 R9 |+ n# ]  J# X% [5 i8 h
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 tvb now,tvbnow,bttvb* G; l1 T+ P# Q: W7 R' W# Z+ \
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,
. q& J$ m5 `' ^9 R% {  ecausing avalanches of debris into the crater.

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