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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
! j8 g1 v/ e. d0 l+ s( k3 H& `公仔箱論壇eruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are 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。; s. J  `$ q# y7 e% ~4 x# x1 ~
active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.
8 _, w0 j/ C8 v0 P; ?' @" \5.39.217.76Some volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens, tvb now,tvbnow,bttvb: b8 m) E- H3 |. m8 _( m) i
erupt rarely andsometimes extremely destructively. Like Etna and Mount St. Helens, manyof the most dangerous
. O3 p0 k2 |: M/ d! {and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions. , s5 S$ a- l5 G9 t! ]: T
They tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.公仔箱論壇* m* n6 C0 |& V- V
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Many of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above 公仔箱論壇1 ^4 q/ s+ |4 W3 m- @
of Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewastvb now,tvbnow,bttvb% {- a" J. G1 Y
taken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash * J+ F! s' [: _) G- m: O+ x/ [
plume reached as high as 50,000 feet.5.39.217.76& z+ y9 A- l8 [  ^
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Augustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra
, W1 a: O9 [  Z) `5.39.217.76satellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000
7 L9 Z- Y1 H0 j; ?  v5.39.217.76years. 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 : ]; S8 h# @- M' o
of Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet
! \: l0 y2 j- I+ j9 |* x+ L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
) n) z: f8 m% N5 p" n4 l公仔箱論壇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 tvb now,tvbnow,bttvb' g6 I; T' k7 b% b4 @0 t8 l) p2 a
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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% U; J4 m& r; ~& EThe smooth white cloud, known as a pileus cloud, topping the eruption column may be made of water condensation caused by rising
3 Q5 ?; O' Z  t* h+ A! ^3 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。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
. v1 \0 H  J6 c: J' Q4 J. p5.39.217.76as a pyroclastic flow.
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' f1 @, q8 f/ D0 I' oThis 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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* v- ~' S. n) W9 ^/ W6 q% F' Etvb now,tvbnow,bttvb    * It could have nothing to do with the eruption and simply be caused by the contrast in temperatures between the ocean and the island.5 p( D* R0 _+ `* A9 s
    * A shockwave from the eruption could have blown a hole in the cloud deck.$ Y" P, j% G# ?  S' `) Y# F
    * 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.
/ N4 ?: @* X& 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。It continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 whentvb now,tvbnow,bttvb1 ?, F! q' o3 ]. ]& J
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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/ K2 s% S& `% }' @" y& iRedoubt 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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5 B- j! ?/ {# p6 bMount Etna is the second tallest volcano in Europe, at almost 11,000 feet. It is one of the most active volcanoes in" C7 a/ Z' J! i( e$ {6 }. I
the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one
; S7 O( i$ v2 a, E& D/ X/ |5.39.217.76captured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in
" G9 R$ a" ?7 ~$ `this picture are from forest fires ignited by lava.
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. a( N3 Q6 y* v- H/ TEtna 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+ [) j' z2 Q9 m' `- ~9 w6 z- \$ i
also 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 5.39.217.76( b  {  }6 a  h: I6 N
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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& g* T/ ]$ `4 o& |, q8 Ftvb now,tvbnow,bttvbPopoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City. 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。$ U* `1 E* R" n+ T
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
- Q- E4 _, J+ F& k0 o) M4 f9 Emultiple 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
7 S( k+ T7 {$ T1 T, S1 n7 Dtvb now,tvbnow,bttvbof frequent activity. The plume reached heights of around 30,000 feet.tvb now,tvbnow,bttvb9 X$ R$ ^( t! P$ ?$ D

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This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the
7 G  m' M/ K2 ~! H/ u! F# f: F5.39.217.76west coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.
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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 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) q1 ]; _/ R4 P1 l# Q4 @# z5 `: z
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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This image of the Sierra Negra volcano in the Galapagos Islands was taken by NASA’s Terra satellite in 2006. Sierra Negra
& G1 s0 L+ N8 k6 K$ c6 ?. r公仔箱論壇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 tvb now,tvbnow,bttvb! v/ o. U( y  C( t/ J! i3 _
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
: o; C1 q2 B$ m4 G% 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。stationary hot spot, volcanoes are formed. The Hawaiian Islands were formed — and continue forming — the same way.1 f: G# Q" o' z9 M4 m

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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. , m- Q) E+ h; j8 p/ u; ?
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 8 V8 K% f6 k9 q
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,
1 J  ?5 E: ~9 R* x: F, F' Pcausing avalanches of debris into the crater.

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