STS099-729-86
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South Florida: The city of Miami encroaches the eastern edge
of the Everglades in Florida. The Everglades is an International
Biosphere Reserve World Heritage Site. This subtropical wilderness
encompasses a relatively flat (does not exceed 2.4 m above sea level)
saw-grass marsh region of 10,000 sq km (4,000 sq miles). The only
source of water in the Everglades is from rainfall. The flow of water
is detectable in this image, slowly moving from Lake Okeechobee to
Florida Bay; the light blue, shallow area (less than 3 m) between the
mainland and the Keys; and the southwestern Florida coast.
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STS099-734-12
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Sunset: A shallow atmosphere displays the various layers by
color . The layer that holds the gases we breath are under the
yellow band called the tropopause.
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STS099-735-46
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Mt. Everest, eastern Himalaya, Tibet Autonomous Region of
China: Mt. Everest (29,028 ft/8848 m; center of photo), also
called Qomolangma Feng, is just north of the border between Nepal and
China. The Himalayas and the Tibetan Plateau are products of the
collision of the Indian and Eurasian tectonic plates. With the
continuing northward march of India, the crust of the Earth has
become thicker and the Tibetan Plateau has been uplifted to an
average elevation of about 15,000 feet. At the summit of Mt. Everest
are fossil-bearing limestones that were deposited beneath the sea
around 510 million years ago (Cambrian to Ordovician time).
Glaciers, moraines, and outwash plains are spectacularly displayed.
Glacial meltwaters in this area feed the Arun River, eventually
reaching the Ganges on the plains of India.
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STS099-749-63
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Manicouagan Impact Crater, Quebec, Canada: One of the largest
and most famous craters in Canada is Manicouagan. Lake Manicouagan
and Lake Mushalagan, frozen in this image, surround the central
uplift of the crater. The original crater diameter was 100 kilometers
and the age has been dated at 214 million years. Shattercones,
striated features found in rocks deformed by the passage of shock
waves, and shattered and brecciated rocks found in the central uplift
confirm the crater's impact origin.
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STS099-749-89
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Alaska Peninsula, Alaska, USA: The Alaska Peninsula and
Aleutian Islands form a long arc that intervenes between the Bering
Sea and the northern Pacific Ocean. This view is of the snowy south
coast of the peninsula, from Chignik Bay and Cape Kumliun (on the
triangular peninsula) northeastward to Chiginagak Bay and David
Island. Port Heiden is the darker area of little ice on the north
coast. Within the rim of the Aniakchak volcanic crater (4450 ft at
highest point) the frozen waters of Surprise Lake are visible.
The North American and Pacific tectonic plates are converging in this
region at a rate of about 5 cm/yr. The Pacific plate descends
beneath North America, producing a deep trench along the south coast;
the Aleutian Trench reaches depths greater than 25,000 ft. In such
regions (subduction zones) volcanoes form on the overriding plate --
the North American plate in this instance; Aniakchak is one of the
many young volcanoes in this arc.
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STS099-753-32
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Galapagos Is: This photograph centers on the two westernmost
Galapagos Islands--seahorse- shaped Isla Isabela and the smaller
round Isla Fernandina to its west. All of the 19 islands are
volcanic in origin, and the craters of several of the shield
volcanoes are visible as circular features on each of the islands.
The two islands shown in this picture contain the most active
volcanoes of the Galapagos. Fernandina last erupted in
January-February 1995, with red-hot lava pouring into the sea. After
20 years of inactivity, Cerro Azul on Isla Isabela, last erupted in
September-October 1998. Cerro Azul is southwesternmost volcano is
Isla Isabela. At 82 miles long, Isla Isabela is the largest of the
islands, and comprises half of the land area of the archipelago. The
islands are famous for their unique flora and fauna. Charles
Darwin's observations of these species in 1835 contributed to the
formation of his ideas on natural selection. Some of the most unique
species include flightless cormorants, Galapagos penguins, giant land
tortoises, and Galapagos finches. The range of Galapagos penguins is
restricted to these western islands where upwelling enriches the
ocean productivity, and the adaptation of a typically Antarctic bird
family to the equator is an ecological marvel. Giant land tortoises
are thought to have the oldest lifespans of any animal on Earth, but
have been driven near to extinction; during the most recent eruption
of Cerro Azul, one tortoise was killed and many had to be relocated.
The 13 species of Galapagos finches on the islands, although varied
in form and lifestyle, are the descendants of an ancestor that
happened to colonize this isolated archipelago. The human population
of the entire archipelago is about 10,000.
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STS099-706-90
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St James Bay, Ontario, Shorelines: Numerous shorelines around
Hudson and St. James Bays are distinctive in winter because of snow
cover. The area shown in this Shuttle image is located in Hannah Bay,
in the southern part of St. James Bay. The river is the Harricanaw
River. Shorelines along the bay were created when the overlying
glaciers retreated and the land underneath rebounded causing the
Hudson/St James Bay waters to retreat northward. These ridges are 100
to 200 m in width and heights can reach up to 7 m. The land along St.
James Bay consists mainly of tidal flats and salt marshes.
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STS099-727-45
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Long Island, New York: The entire length of Long Island, New
York is visible in partial sunglint from Lower Bay to Block Island
Sound. The origin and shape of Long Island is due to continental
collision and glaciers that once dominated the landscape. A collision
between North America and Africa about 300 million years ago caused
the Appalachian Mountains to rise. Streams carried sediment from the
eroding Appalachians and also carved a valley that would one day
become Long Island Sound. Retreating ice sheets 22,000 years ago
allowed the land to rebound, the highest points becoming Long Island.
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STS099-715-77
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Sea Ice Vortex: Both topography and bathymetry combine with
wind and sea currents to produce this pattern of sea ice in the
extreme southern Sea of Okhotsk. The rugged shoreline of north
Hokkaido and the Kurile Archipelago have channeled northerly winds
and surface waters into a gyre here, clearly depicted in the pattern
of sea ice.
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STS099-729-45
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Erg Chech Dunes, Algeria: Linear dunes in the Algerian Saharan
sand sea known as the Erg Chech, have been built up over thousands
years into masses elongated roughly parallel with the prevailing
northeast winds. Dune chains in the northern (upper) half of the view
are 5-8 km apart. A slight change in orientation and an increase in
the density of dunes appears across the middle of the view. Such
changes usually relate to changes in sand supply, and also to
topographic scarps over which the dunes pass. Obstacles like
scarps and hills locally cause a leftward deflection (in the northern
hemisphere) in wind direction, an effect which can be seen here in
the dune orientation in the middle of the photo. Dunes in the
lower part of the view are 2-5 km apart. White patches are small dry
lakes at low points in the underlying rock surface. The strong red
color in some dunes near the edge of the dune field (left margin) is
iron staining derived from sand particles blown into the dunes from
the underlying iron-rich soils. A dune free area appears in the lower
left corner.
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