The Kamchatka Peninsula is one of the most active volcanic regions along the Pacific Ring of Fire. Over a hundred volcanoes stretch across this land mass, about thirty of which have reupted recently.
Since late April, this region has been very active. Shiveluch, one of Kamchatka’s most active volcanoes, began its latest activity with gas and steam emissions in mid- to late March 2007. This image was taken by astronauts aboard the International Space Station (ISS) around mid-morning on or around March 21, 2007. It shows a steam plume, probably containing minor amounts of ash, blowing westward from the summit of the volcano. There were subsequent eruptions on March 29 and 30. 
The volcano’s southern flank, clearly visible in this northeast-looking view, is dominated by a horseshoe-shaped caldera formed during an eruption in the late Pleistocene Epoch (the last ice age, the geologic time period that ended roughly 10,000 years ago). The caldera was subsequently blanketed by additional ash deposits, and in this image is highlighted by the surrounding snow.
On April 29, the volcano Klyuchevskaya Sopka, which is also located at Kamchatka, has spewed the powerful vapor trail to the height of up to 1.5 kilometres above the peak, and amplitude of the volcanic tremor is reported to be growing. Two lava flows came down from the crater.
Sources: NASA and Vladivostok Times
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