Sitting in the middle of the Iranian plateau, the Dasht-e Kavir, or Great Salt Desert, is the planet’s 24th largest desert. From the ground, the desolate sand dues and bordering mountain range are imposing and beautiful. From above, you get an entirely different perspective. The US Geological Survey-operated Landsat 7 satellite captured a stunning image of the Dasht-e Kavir from above (seen below) way back in 2000. The Landsat 7 satellite operated from 1999-2024.
The Dasht-e Kavir, or Great Salt Desert, is the largest desert in Iran. It is primarily uninhabited wasteland, composed of mud and salt marshes covered with crusts of salt that protect the meager moisture from completely evaporating. This image was taken by the Landsat 7 satellite on October 24, 2000. It is a false-color composite image made using infrared, green and red wavelengths. The image has also been sharpened using the sensor’s panchromatic band.Credit: NASA/USGS Landsat 7; NASA Earth Observatory
The Landsat 7 satellite isn’t the only craft capturing beautiful images of our planet from above. Other satellites and crew members on the International Space Station have also documented Earth, taking shots of everywhere from Georgia, USA to the islands of New Caledonia in the South Pacific.
In a dense swampland in Georgia, just north of the Florida border, you find the headwaters of the Suwannee River (upper right). The Suwannee is known as a “blackwater river” because of its dark-brown waters laden with organic material. This river system has been called one of the most pristine in the United States, but some environmental pressures are putting that distinction in jeopardy.
Unlike other blackwater rivers, the Suwannee maintains its inky color along its entire 400-kilometer (250-mile) journey to the sea. When the river finally meets the Gulf of Mexico along Florida’s Big Bend—that portion of coast where the state’s panhandle curves to meet its peninsula—its dark waters act like a tracer, revealing where the river water mixes with the sea.
That mixing was on display on February 20, 2015, when the Operational Land Imager on NASA’s Landsat 8 satellite captured this view.Credit: NASA Earth Observatory image by Dr. Alice Alonso, using Landsat satellite data from the U.S. Geological Survey. Caption adapted from Laura Rocchio, NASA Landsat Science Outreach.
Like distant galaxies amid clouds of interstellar dust, chunks of sea ice drift through graceful swirls of grease ice in the frigid waters of Foxe Basin near Baffin Island in the Canadian Arctic. Sea ice often begins as grease ice, a soupy slick of tiny ice crystals on the ocean’s surface. As the temperature drops, grease ice thickens and coalesces into slabs of more solid ice.
This image was acquired on August 4, 2002, by the Landsat 7 satellite. Credit: USGS/NASA/Landsat 7
This image, showing tidal flats and channels on Long Island, in the Bahamas, was taken by an Expedition 26 crew member onboard the International Space Station. The islands of the Bahamas in the Caribbean Sea are situated on large platforms made mainly from carbonate sediments ringed by fringing reefs — the islands themselves are only the parts of the platform currently exposed above sea level. The sediments are formed mostly from the skeletal remains of organisms settling to the sea floor; over geologic time, these sediments will consolidate to form carbonate sedimentary rocks such as limestone. Darker blue shows deeper water, while light blue-green shows shallow water on the tidal flat. The continually exposed parts of the island are seen in brown, a result of soil formation and vegetation growth (left).Credit: Expedition 26 crew member onboard the International Space Station, courtesy of NASA
Every summer, phytoplankton spread across the northern basins of the North Atlantic and Arctic Oceans, with blooms spanning hundreds and sometimes thousands of miles. Nutrient-rich, cooler waters tend to promote more growth among marine plants and phytoplankton than is found in tropical waters. Blooms in summer 2018 off Scandinavia seem to be particularly intense.
On July 18, 2018, the Operational Land Imager (OLI) on Landsat 8 acquired a natural-color image of a swirling green phytoplankton bloom in the Gulf of Finland, a section of the Baltic Sea. Note how the phytoplankton trace the edges of a vortex; it is possible that this ocean eddy is pumping up nutrients from the depths.Credit: NASA Earth Observatory images by Joshua Stevens and Lauren Dauphin, using Landsat data from the U.S. Geological Survey and MODIS data from LANCE/EOSDIS Rapid Response
From NASA’s Operation IceBridge campaign in Alaska: A high altitude view of Icy Bay, in the Wrangell-Saint Elias Wilderness. Just a century ago, this body of water was covered in ice.Credit: NASA
Perhaps the most impressive of cloud formations, cumulonimbus (from the Latin for “pile” and “rain cloud”) clouds form due to vigorous convection (rising and overturning) of warm, moist and unstable air. Surface air is warmed by the sun-heated ground surface and rises; if sufficient atmospheric moisture is present, water droplets will condense as the air mass encounters cooler air at higher altitudes. The air mass itself also expands and cools as it rises due to decreasing atmospheric pressure, a process known as adiabatic cooling. This type of convection is common in tropical latitudes year-round and during the summer season at higher latitudes.
The image, taken while the International Space Station was located over western Africa near the Senegal-Mali border, shows a fully formed anvil cloud with numerous smaller cumulonimbus towers rising near it. Credit: NASA
The Mackenzie River in Canada plays a major role in Arctic climate as warmer fresh water mixes with cold seawater. This image was taken by the Operational Land Imager on the Landsat 8 satellite on July 18, 2017.Credit: Source: NASA/USGS Landsat 8; Norman Kuring, GSFC
This beautiful image, taken on 11 January 2001, shows a geological formation in the Maur Adrar Desert in Mauritania, Africa. Known as the “Richat Structure,” this snail-shell-like formation was created when a volcanic dome hardened and gradually eroded, exposing onion-like layers of rock.Credit: NASA/U.S. Geological Survey/Landsat-7/Goddard Space Flight Center
Dagze Co (Lake) is one of many inland lakes in Tibet. In glacial times, the region was considerably wetter, and lakes were correspondingly much larger. This is evident by the numerous fossil shorelines that circle the lake, and attest to the presence of a larger, deeper lake. Changes in climate have resulted in greater aridity of the Tibetan Plateau, and drying up of the lakes. Image taken by the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) on October 8, 2001.Credit: NASA/GSFC/METI/ERSDAC/JAROS and the U.S./Japan ASTER Science Team
Guinea-Bissau is a small country in West Africa. Complex patterns can be seen in the shallow waters along its coastline, where silt carried by the Geba and other rivers washes out into the Atlantic Ocean. Image taken by Landsat 7 on December 1, 2000. Credit: USGS/NASA/Landsat 7
In the style of Van Gogh’s painting ‘Starry Night,’ massive congregations of greenish phytoplankton swirl in the dark water around Gotland, a Swedish island in the Baltic Sea. Phytoplankton are microscopic marine plants that form the first link in nearly all ocean food chains. Population explosions, or blooms, of phytoplankton, like the one shown here, occur when deep currents bring nutrients up to sunlit surface waters, fueling the growth and reproduction of these tiny plants. Image taken by Landsat 7 on July 13, 2005.Credit: USGS/NASA/Landsat 7
This photo, taken on January 22, 2001 by the Landsat-7 satellite, shows Akpatok Island, which lies in Ungava Bay in Canada. Accessible only by air, Akpatok Island rises out of the water as sheer cliffs that soar 500 to 800 feet (150 to 243 meters) above the sea surface. The island is an important sanctuary for cliff-nesting seabirds. Numerous ice floes around the island attract walruses and whales, making Akpatok a traditional hunting ground for native Inuit people.Credit: NASA/USGS Landsat 7 satellite; NASA Earth Observatory
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