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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 1 f! m) q  t/ Y) {$ Y7 s
eruptions. Around 550volcanoes have erupted at least once in historic times, and around 50or 60 are tvb now,tvbnow,bttvb' o$ q+ K0 a; w$ i1 k; a0 }' y7 m+ }- M9 M
active each year. On any given day, as many as 10 volcanoesmay be spewing ash or lava somewhere on Earth.
9 x! @1 n  [- B# T5.39.217.76Some volcanoes, such as Mount Etna in Italy, erupt almost constantlyfor years on end. Others, like Mount St. Helens, $ |% I0 k: H) \6 d
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。2 X, X+ B: m  {- a: @) O
and explosive erupters are stratovolcanoes, whichare made of layers of ash and lava from previous eruptions. tvb now,tvbnow,bttvb. Z* U: f" A' G. l* y% ?. J$ u. E
They tendto be steep-sided cone-shaped volcanoes and often rise strikingly abovethe surrounding landscape.
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Many of the stunning images of eruptions captured from space are ofviolent stratovolcanoes, such as the one above
7 [2 R- [% ^3 P4 b- C* E  u: iof Kliuchevskoi, themost active volcano on Russia’s Kamchatka peninsula. The image abovewas
# J! H2 n  @; y' }2 Ntaken by astronauts on the space shuttle Endeavour in 1994, as an eruption was just getting underway. The ash
) ?" p' J8 Y4 X3 ]0 rTVBNOW 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。plume reached as high as 50,000 feet.
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3 n4 b0 b! F8 F' PAugustine Volcano is a 4,100-foot-tall, 7-mile-wide stratovolcano. This eruption was captured by NASA’s Terra
& M7 u' `" k! {7 w9 t" o3 P- X公仔箱論壇satellite in 2006. Augustine’s dome collapsed in 1883, during its largest historical eruption. It has been erupting for at least 40,000 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/ ^- W  F9 }$ Z
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 K0 D: Y8 C% N$ B, Dof Fire. Volcanic activity here is caused by the subduction of the Pacific plate beneath the North American plate. As the wet
6 O& W) o  b1 I5 O4 Eocean crust descends into the molten mantle below, superheated water is squeezed out and rises up to melt the bottom of - R0 Z& L' c2 l6 k
the continental crust, creating magma that drives the volcanic eruptions7 b2 g; `8 C3 b
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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。$ K6 k) V! w' Z. B& C
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 3 |. v" i2 |; X9 L0 ^
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 公仔箱論壇" t0 l2 v5 t' _# s0 n2 l3 x/ k. k
as a pyroclastic flow.tvb now,tvbnow,bttvb' U( x1 e6 y" w

. f1 s/ b( B# s7 w4 w) i0 U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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# a- T! B% S8 k, a9 w2 K9 K! Htvb 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.
9 a0 Y0 a# o5 N% n  k  w4 X    * A shockwave from the eruption could have blown a hole in the cloud deck.+ u8 W0 X! l9 ]% J1 [
    * As the plume rose, air flowed downward along the sides and became warmer and evaporated the clouds.
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8 C5 ?5 c/ L+ H' x0 ?; dtvb now,tvbnow,bttvbAlaska’s Redoubt Volcano erupted five times in one night this year after almost three decades of relative quiet.
2 J/ Z! ]; h, g) t2 J5 y5.39.217.76It continued erupting on and off for weeks afterward. This image was taken by the commercial satellite GeoEye-1 on March 30 when
2 l. d( K/ y1 t- X6 W' f5.39.217.76 the ash reached heights of 27,000 feet. The volcano’s alert level is still “advisory,” and the aviation color code is yellow.5.39.217.76, W; A" O- R0 K* S9 G+ L* ], n5 b

% u8 N; s# b* ~% t. `) ~5.39.217.76Redoubt is a 10,200-foot tall stratovolcano 100 miles southwest of Anchorage in the Aleutian Range, west of the Cook Inlet.5.39.217.76/ H, I9 Y) @; N

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" ^. n9 P' R; z$ C% d5 o; s8 A' U' F2 Ttvb now,tvbnow,bttvbMount Etna is the second tallest volcano in Europe, at almost 11,000 feet. It is one of the most active volcanoes in
" Y: i' a  I  q8 s0 }  W. ?. p/ i公仔箱論壇 the world and is erupting nearly continuously. It is no surprise that there are many great photos of this volcano erupting, including this one 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# c0 t* K* W5 Y
captured by astronauts on the International Space Station in 2002. The lighter colored plumes of smoke on the slope of the volcano in # R% ]3 d2 Y+ M4 R
this picture are from forest fires ignited by lava.
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2 `9 m  ~% t1 [% F公仔箱論壇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
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% r1 k1 l) U2 \. o) E5.39.217.76A NASA astronaut spotted this eruption of Cleveland Volcano from the International Space Station in 2006. The volcano is 5,700 feet high
7 c0 {- A) n1 r: G# F: Tand claimed the only known eruption-related death in Alaska’s Aleutian Islands in 1944. Its symmetrical, cone shape is typical of stratovolcanoes., L* e) L* W9 r+ b) i, J3 I
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! q2 |/ J  V. S' N4 k, S, W5.39.217.76Popoépetcatl, which means “smoking mountain” in the Aztec language, is a very active volcano just 44 miles outside Mexico City.
) @4 c0 {& A( b7 I( VThe 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
3 s) B5 V0 D8 z: Smultiple 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。0 I  z1 ?& T) h3 n$ _
of frequent activity. The plume reached heights of around 30,000 feet.5.39.217.76, Q0 F7 D3 }6 H

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This eruption of Chaitén caldera in Chile was photographed from the International Space Station in May 2008. Volcanism along the
! C& T: @" Z! i$ V/ A7 h2 X& a5 ?% 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。west coast of South America is the result of subduction of the oceanic Nazca plate beneath the South American plate.! J6 L- X% T% q$ k# O& G5 o( p
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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 公仔箱論壇1 B4 c' @/ R3 K0 q
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
) ~; b! ?) `; W4 iis 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
: D) m! m' d" f& O6 B% Atvb now,tvbnow,bttvbformed 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 tvb now,tvbnow,bttvb& S; j, G; T6 r8 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. 7 e- f* u0 _$ i
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
3 y1 C# N5 L. Q1 j. Athat 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,
3 {( y( B0 q% M# J: b, F0 u# Ttvb now,tvbnow,bttvbcausing avalanches of debris into the crater.

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