This week’s satellite image was acquired over the eastern part of Mexico City.
The area pictured lies within central Mexico’s highlands plateau called the Valley of Mexico. This valley was originally covered by the waters of Lake Texcoco but over the centuries the water has been drained. The area that has not been built up is today used for hydraulic management and is made up of reservoirs and ponds such as the large, dark Nabor Carrillo lake pictured here.
The area receives more than 100,000 migratory birds each year that travel through the Central Migratory Flyway, and is a key resting, feeding and breeding ground for several species of shorebirds.
In contrast to the open space of the former Lake Texcoco, Mexico City is a densely populated metropolitan area (left and bottom).
We can see the runways of the international airport on the far left. South of the airport is the Alameda Oriente recreational park with its somewhat spiral artificial lake. North of the airport, El Bosque de San Juan de Aragón is another park and important green area.
City parks play a large role in the city’s effort to alleviate air pollution. In the early 1990s, pollution was believed to cause hundreds of deaths each year. Air quality has improved in recent decades through a series of government efforts to cut emissions.
This image, acquired by Korea’s Kompsat-2 satellite on 21 December 2012, is also featured on the Earth from Space video program.
Image credit: KARI/ESA
This satellite image was acquired over the edge of a salt marsh near the northeast Caspian Sea in southwestern Kazakhstan.
The Caspian Sea (not pictured) is the largest inland body of water by surface area. With an average depth of about 5 m, the northern part of the Caspian is very shallow, while the central and southern parts of the sea are much deeper. The salinity of the waters also change from north to south, being more saline in the northern, shallow waters and less in the south.
The salt marsh in the upper section of this image was once a gulf of the Caspian Sea, but fluctuating sea levels over the last decades cause it to be cut off occasionally from the main body of water and even dry up. In this image, it appears that the water has evaporated, leaving behind a white salt crust.
Rock formations dominate the central part of the image, while a plateau stretches south and east (not pictured). The visible shapes in combination with the dark color of the rocks may indicate that they are volcanic, with water erosion evident in the finger-like runoff patterns.
The grey rim between the land and salt pan comes from the sedimentary runoff from the land mixing with the saltwater. When the marsh is dry, a greyish color is left behind.
The arid climate in this region makes it easy to acquire optical imagery from satellites, without the obstruction of visibility by clouds.
This image was acquired on 6 November 2012 by the Korea Aerospace Research Institute’s Kompsat-2 satellite and is featured on the Earth from Space video program.
Photo credit: KARI/ESA
This satellite image shows an area of the Himalaya mountain range in northeastern Nepal, about 8 km south of Mount Everest (not pictured).
The Himalayas are the world’s highest mountain range and home to the world’s highest peak, Mt Everest (about 8850 m), as well as dozens of other peaks over 7000 m high. These high peaks are covered permanently with snow.
The range is also home to thousands of glaciers, including the Imja glacier in the upper-central part of this image. Studies have shown an increase in the rate of glacial retreat for Imja and many other glaciers in the region – and in the world.
Glaciers are the largest reservoirs of freshwater on our planet, and their melting or growing is one of the best indicators of climate change. Satellite radar data can help monitor changes in glacier mass and, subsequently, their contribution to rising sea levels.
Glacial runoff from the Himalayas has a direct effect on the nearby rivers such as the Indus and Ganges, and is very important for lower-lying regions where there is a very large human population.
At the foot of the Imja glacier is the Imja lake, pictured in the upper-left. Melt-water makes this one of the fastest growing lakes in the Himalayas, and a threat to downstream communities.
This image, also featured in the Earth from Space video program, was acquired by the Kompsat-2 satellite on 14 January 2013.
Photo credit: KARI/ESA
This false-color satellite image shows the Kumbunbur Creek in Australia’s Northern Territory, about 260 km southwest of the city of Darwin.
The green ‘branches’ of what looks like a tree are the waterways of runoff that flow into the Timor Sea (not pictured).
The false-color makes vegetation appear bright red, and we can clearly see how vegetation grows mainly along the waterways. Vegetation is more evenly dispersed across the plain to the north.
The image was captured by the Kompsat-2 satellite on 20 September 2011, near the end of the dry season. The dry areas with a somewhat dull color in this image become flooded mudflats during the rainy season.
The rainy season occurs during a tropical area’s summer months because of increased heat from the Sun’s more direct impact angle. Higher temperatures lead to an increase in evaporation and rising, warm air masses. This air expands and cools, leading to the formation of cumulus clouds, and almost daily rainfall and thunderstorms.
As seasons change, the location of these rainfalls travels to areas with the highest Sun impact angles, resulting in wet and dry seasons in different zones of the tropics.
The tropics are the region of Earth north and south of the equator. Some areas of northern Australia are part of the tropical climate zone.
This image is featured on the Earth from Space video program.
Image credit: KARI/ESA
The city of Jeddah’s seaport on Saudi Arabia’s western coast is pictured in this image from the Kompsat-2 satellite.
The second largest city in the country, Jeddah has a population of over five million people. The city is a gateway to Islam’s holiest city of Mecca, which lies about 60 km to the east, as well to the holy city of Medina, about 320 km north.
It is also an important commercial hub, with its port located in the middle of an important shipping route between east and west. Zooming in, we can see some large container vessels in the port.
Near the bottom of the image, the large circles are the tanks of an oil refinery. The oil industry comprises about 45% of Saudi Arabia’s gross domestic product, and 90% of export earnings. Saudi Arabia is the world’s number-one oil exporter, and therefore plays a major role in the global energy industry. Its policies on the production and export of oil, natural gas and petroleum products have a major impact on the energy market, as well as the global economy.
The Red Sea’s coral reefs are visible off the coast. In fact, this is one of the few places along this coastline with a gap in the reef, enabling large vessels to approach the coast.
This image, also featured in the Earth from Space video program, was acquired on 17 March 2013 by the Korea Aerospace Research Institute’s Kompsat-2 satellite.
Photo credit: KARI/ESA
The snow-covered southern Polish city of Kraków is pictured in this image from the Kompsat-2 satellite.
The Vistula River snakes across the top of the image. The part of the river pictured flows from west to east as it winds northwards and empties into the Baltic Sea (not visible).
Kraków sits in a valley at the foot of the Carpathian Mountains and has a number of important nature reserves of great ecological value. Dubbed the European Capital of Culture in 2000, the city has an extensive cultural heritage across the epochs of Gothic, Renaissance and Baroque architecture, and is home to one of the oldest universities in the world: Jagellonian University.
Just north of the river at the center-left portion of the image is the medieval Old Town or historic central district. The area is home to Europe’s largest market square, along with numerous historic houses, palaces and churches.
Listed as a UNESCO World Heritage Site since 1978, the Old Town was the center of Poland’s political life until King Sigismund III Vasa moved his court to Warsaw in the late 1500s.
This image was acquired on 5 February 2010 by the Korea Aerospace Research Institute’s Kompsat-2 satellite.
Image credit: KARI/ESA
This false-color composite image from the Kompsat-2 satellite shows part of the Qarhan Salt Lake on the Tibetan Plateau in China.
There are multiple salt lakes across this region, but Qarhan’s 5850 sq km make it the largest. It holds an estimated 60 billion tonnes of salt, and is also a major production base for potassium and magnesium.
In this image, we can see division of the salt evaporation ponds. While the false color makes them appear blue, salt ponds naturally range in color depending on their algal concentration and salinity.
The nearest city, Golmud, sits about 50 km to the southwest (not pictured).
This image was acquired on 4 December 2008 by the Korea Aerospace Research Institute’s Kompsat-2.
ESA supports Kompsat as a Third Party Mission, meaning it uses its ground infrastructure and expertise to acquire, process and distribute data to users.
Photo credit: KARI/ESA
This Kompsat-2 image, acquired on 6 July 2012, shows the Amazon River in the heart of northern Brazil’s rainforest. The false color makes land vegetation appear pink, while water appears green and dark blue. In the upper-right corner, we can see some sparse clouds. The shades of pink vary – the bolder color representing thick vegetation with lighter pink showing where trees were possibly cut down. In fact, in the upper-left portion of the image, there’s a clear line between the two shades, showing where vegetation was cut. The white dots show man-made structures. With their unique view from space, Earth observation satellites have been instrumental in highlighting the vulnerability of the rainforests by documenting the scale of deforestation.
This image is featured on the Earth from Space video program.
Image credit: KARI/ESA
Uluru/Ayers Rock in the Australian outback is featured in this image from the Kompsat-2 satellite. The rock formation is anInselberg– German for ‘island mountain’ – a prominent geological structure that rises from the surrounding plain.
Hundreds of millions of years ago, this part of Australia was a shallow sea. Layers of sandstone settled on the ocean floor and were compressed. These hardened, horizontal layers were uplifted and tilted almost 90º upwards to their present position. The rock eroded slower than the surrounding softer deposits until the monolith stood high above an otherwise flat surface. From this perpendicular angle of the satellite acquisition, we can see those layers that were once horizontal and now appear to cut across the top of the formation.
The Korea Aerospace Research Institute’s Kompsat-2 satellite acquired this image on 15 September 2011. ESA supports Kompsat as a Third Party Mission, meaning it uses its ground infrastructure and expertise to acquire, process and distribute data to users.
This image is featured on the Earth from Space video program.
Photo credit: KARI/ESA
The foothills of the Andes mountains near the southern coast of Peru were captured by the Kompsat-2 satellite on 4 May 2011. The Andes stretch about 7000 km from Venezuela down South America’s west coast to the top of Argentina. The mountain range is the result of the Nazca and Antarctic tectonic plates moving under the South American plate – a geological process called ‘subduction’. This process is also responsible for the Andes range’s volcanic activity.
Photo credit: KARI/ESA
Korea’s Kompsat-2 satellite captured this image over the sand seas of the Namib Desert on 7 January 2012. The blue and white area is the dry river bed of the Tsauchab. Black dots of vegetation are concentrated close to the river’s main route, while salt deposits appear bright white. Running through the river valley, a road connects Sossusvlei to the Sesriem settlement. At the road’s 45th kilometer, seen at the lower-central part of the image, a white path shoots off and ends at a circular parking area at the base of a dune. This is Dune 45, a popular tourist stop on the way to and from Sossusvlei. In this image, there appears to be some shadow on the western side. From this we can deduce that the image was acquired during the late morning.
ESA supports Kompsat as a Third Party Mission, meaning it uses its ground infrastructure and expertise to acquire, process and distribute data to users.
This image is featured on the Earth from Space video program.
Photo credit: KARI/ESA
