(23 May 2006) --- Eruption of Cleveland Volcano, Aleutian Islands, Alaska is featured in this image photographed by an Expedition 13 crewmember on the International Space Station. This image, acquired shortly after the beginning of the eruption, captures the ash plume moving west-southwest from the summit vent. The eruption was short-lived; the plume had completely detached from the volcano summit two hours later.
Photo credit: NASA
(27 July 2003) --- Photographed by an Expedition 7 crewmember onboard the International Space Station (ISS), this image shows the limb of the Earth at the bottom transitioning into the orange-colored troposphere, the lowest and most dense portion of the Earth's atmosphere. The troposphere ends abruptly at the tropopause, which appears in the image as the sharp boundary between the orange- and blue- colored atmosphere. The silvery-blue noctilucent clouds extend far above the Earth's troposphere. The sliver of the setting moon is visible at upper right.
Photo credit: NASA
(10 March 2003) --- This nighttime view of Los Angeles, California was captured by one of the Expedition Six crewmembers on board the International Space Station (ISS). In the north, Hollywood is nestled against the south side of the Santa Monica Mountains. On the coast, Los Angeles International Airport (LAX) and the port facilities at Long Beach Naval Shipyards are also bright spots. The bright lights of Disneyland in Anaheim are also a standout feature.
Photo credit: NASA
(31 August 2005) --- Aurora Borealis and lights in Finland, Russia, Estonia and Latvia are featured in this digital still picture taken by the Expedition 11 crew aboard the International Space Station. If it were daylight parts of the Eastern Baltic Sea would be visible. The cluster of stars to the lower right of the thin crescent Moon is the Praesepe or Beehive Cluster in Cancer. Just to the right of that is the planet Saturn.
Photo credit: NASA
(8 Aug. 2001) --- This image, recorded with a digital still camera by one of the Expedition Two crew members onboard the International Space Station, is a glimpse of the barren moon through the Earth’s limb. With no atmosphere, and therefore no limb of its own, the edge of the moon arcs crisply against the backdrop of space. Some of the most breathtaking views of Earth taken from space are those that capture our planet’s limb. When viewed from the side, the Earth looks like a flat circle, and the atmosphere appears like a halo around it. This glowing halo is known as the limb. Viewed from satellites, space shuttles, and even the moon, the image of this luminous envelope of gases shielding the life on our planet from the dark, cold space beyond rarely fails to fascinate us.
Photo credit: NASA
(28 January 2004) --- This image featuring Mt. Everest and Makalu was taken by an Expedition 8 crew member on the International Space Station (ISS). Crew members on board the Station have a unique view of the world because of their position in a low orbit (200 nautical miles, 360 kilometers) relative to satellites and their ability to look at any angle out the windows of the spacecraft. ISS crew members recently took advantage of their vantage point to photograph this oblique view of the Himalayas looking south from over the Tibetan Plateau. At first glance, one might think that the image looks like a picture taken from an airplane; until you remember that the summits of Makalu [left (8,462 meters: 27,765 feet)] and Everest [right (8,850 meters; 29,035 feet)] are at the heights typically flown by commercial aircraft, and could never be seen this way from an airplane.
Photo credit: NASA
(16 Feb. 2003) --- Green aurora dancing over the night side of the Earth just after sunset on February 16, 2003. The reds and blues of sunset light up the air layer to the west. The image was recorded with a 58 mm lens on a digital still camera. Because auroras follow Earth's magnetic field, they are observed at Earth's poles when the oxygen and nitrogen atoms start to glow when bombarded by charged particles coming from the sun. In a sense, auroras are the "neon lights" of the poles.
Photo credit: NASA
(5 Sept. 2006) --- Bernese Alps, Switzerland is featured in this image photographed by an Expedition 13 crewmember onboard the International Space Station. The formidable mountain system of the Alps stretches across much of central Europe, with seven countries claiming portions of the mountains within their borders (Germany, France, Switzerland, Italy, Liechtenstein, Austria, and Slovenia). The glacial landscape of the Bernese Alps, located in southwestern Switzerland, is well illustrated by this view. The image was taken by a crewmember looking north-northwest while the station was located over the Mediterranean Sea between Corsica and Italy -- this oblique viewing angle imparts a sense of perspective to the image. This type of viewing angle complements more nadir (downward)--viewing imagery of the region. Three of the higher peaks of the central Alps are visible--Jungfrau (4,158 meters), Moench (4,089 meters), and Eiger (3,970 meters). To the east and south of the Jungfrau is the Aletsch Glacier, clearly marked by dark medial moraines extending along the glacier's length parallel to the valley axis. The moraines are formed from rock and soil debris collected along the sides of three mountain glaciers located near the Jungfrau and Moench peaks -- as these flowing ice masses merge to form the Aletsch Glacier, the debris accumulates in the middle of the glacier and is carried along the flow direction. According to geologists, Lake Brienz to the northwest was formed by the actions of both glacial ice and the flowing waters of the Aare and Lutschine rivers, and has a maximum depth of 261 meters. The lake has a particularly fragile ecosystem, as demonstrated by the almost total collapse of the whitefish population in 1999. Possible causes for the collapse, according to the scientists, include increased water turbidity associated with upstream hydropower plant operations, and reduction of phosphorus (a key nutrient for lake algae, a basic element of the local food web) due to water quality concerns. Photo credit: NASA
(31 May 2006) --- Nukuoro Atoll, Federated States of Micronesia. Located just north of the equator (3.85 degrees N, 154.9 degrees E), this classically-shaped atoll is part of the Caroline Island chain, which stretches northeast of Papua New Guinea in the western Pacific (roughly north of Guadalcanal, and southeast of Guam and Truk Islands). Nukuoro is one of 607 islands that make up the Federated States of Micronesia, a United Nations Trust Territory under US administration. About 900 people live on the atoll whose lagoon is 6 kilometers in diameter. The image shows the sandy atoll with 42 distinct patches of vegetation. These patches are located on the northeast and east portions of the atoll that face the dominant Easterly winds. The image shows the larger fields and settlement on the inland side of the largest forest patch protected from the wind. The land surface is probably slightly higher above sea level here because dunes build up preferentially on wind-facing slopes where beach sand is mobilized by wind. Swells driven by these winds can be seen approaching from the east-southeast (right) and wrapping around the atoll to produce an interference pattern on the downwind side. Water in the lagoon is notably calm in comparison. Coral heads appear in the lagoon, one dead center of the image. Photo credit: NASA
(31 March 2008) --- Harrat Khaybar, Saudi Arabia is featured in this image photographed by an Expedition 16 crewmember on the International Space Station. The western half of the Arabian peninsula contains not only large expanses of sand and gravel, but extensive lava fields known as haraat (harrat for a named field). One such field is the 14,000-square kilometer Harrat Khaybar, located approximately 137 kilometers to the northeast of the city of Al Madinah (Medina). According to scientists, the volcanic field was formed by eruptions along a 100-kilometer long north-south linear vent system over the past 5 million years; the most recent recorded eruption took place between 600 - 700 A.D. Harrat Khaybar contains a wide range of volcanic rock types and spectacular landforms, several of which are represented in this view. Jabal al Quidr is built from several generations of dark, fluid basalt lava flows; the flows surround the 322--meter high stratovolcano (Jabal is translated as "mountain" in Arabic). Jabal Abyad, in the center of the image, was formed from a more viscous, silica-rich lava classified as a rhyolite. While Jabal al Quidr exhibits the textbook cone shape of a stratovolcano, Jabal Abyad is a lava dome -- a rounded mass of thicker, more solidified lava flows. To the west (top center) is the impressive Jabal Bayda'. This symmetric structure is a tuff cone, formed by eruption of lava in the presence of water. This leads to the production of wet, sticky pyroclastic deposits that can build a steep cone structure, particularly if the deposits consolidate quickly. White deposits visible in the crater of Jabal Bayda' (and two other locations to the south) are formed from sand and silt that accumulate in shallow, protected depressions. The presence of tuff cones -- together with other volcanic features indicative of water -- in the Harrat Khaybar suggest that the local climate was much wetter during some periods of volcanic activity. Today, however, the regional climate is hyperarid -- little to no yearly precipitation -- leading to an almost total lack of vegetation. Photo credit: NASA
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