Majestic sands: Desert dunes, view from space

Is it Friday today? Then why not be distracted by a popular science photo article on what occupies one fourth of the land mass of our planet?

Deserts are reputedly deserted and lifeless, but at the same time they are incredibly beautiful, especially when you look at them from above. Different types of sand, topography, wind and climate all together create a tremendous amount of landscapes. Wandering dunes form an infinite number of ever-changing shapes.

The photos in this collection were taken by astronauts and satellites and captured the most beautiful, most memorable, vast desert areas of our planet.
')
Original article at wired.com
Translation of the article into translated.by
Worked on the translation

alco
hellt

Algerian Sand Sea

Look at Yandex. Photos (Photo by NASA)
The sandy sea (erg) Issaouane extends over 39,000 sq. Km. in eastern Algeria. This sandy sea in the middle of the Sahara desert consists of three types of dunes. Mega-dunes, also known as whale backs, formed over hundreds of thousands of years and reach hundreds of kilometers in length. Mesoscale dunes form the top of the mega-dunes, their gradual displacement can be seen only after decades. Smaller dunes form on and around larger dunes. They take different forms under the influence of the winds and are in constant motion.

In the above photograph taken by astronauts of the ISS in 2005, mesoscale dunes took the form of star dunes resembling a starfish and crescent dunes. In the photo below, taken by astronauts of the ISS in 2006, huge rounded shapes are mega-dunes. The dunes of the smallest size look like wrinkles against the background of large dunes.

Look at Yandex. Photos (Photo by NASA)

California Imperial Dunes

Look at Yandex. Photos (Photo by NASA)
Algodonskoe dune field, located on the border between Mexico and Arizona and California, reaches a width of almost 10 km and stretches over 70 km. These dunes are best known as the dunes of the planet Tatooine in the Star Wars universe. In their open spaces is the official National Park of recreation, which is managed by the Land Management Bureau. The only artificial structure among the dunes is the American Canal, which cuts its way through the dunes near their rise near the agricultural land of Mexico. It can be seen on the right of the photo. The photo was taken by astronauts from the ISS in 2005.

White Sands in New Mexico

Look at Yandex. Photos (Photo by NASA)
The sands of the dunes of the “White Sands National Monument” are particles of gypsum, an evaporite mineral that has accumulated as a result of the evaporation of large masses of water. In place of these dunes a few hundred million years ago, the shallow sea dried up. A few thousand years ago a huge lake evaporated here. Such dunes are quite rare, because gypsum is usually easily dissolved in water and spread by rivers. In this place its particles are preserved due to the fact that there is no access to the sea from the pool where they are located. In turn, the water from the rivers flowing into this basin dried out, instead of washing out the gypsum.

Dunes in southern New Mexico cover more than 700 square kilometers. Nearly half of the square is under the protection of the “White Sands National Monument”. This photograph of the terrain was taken using the Advanced Land Imager aboard NASA's Earth Observing-1 satellite on June 27th.

Desert Rub-al-Khali (Empty Quarter) in Saudi Arabia

Look at Yandex. Photos (Photo by NASA / USGS)
This aptly named desert is the world's largest sandy sea, covering an area of more than 580,000 square kilometers. The photo above shows a part of it, located in Saudi Arabia, but this sea also covers parts of Yemen, Oman and the United Arab Emirates.

Look at Yandex. Photos (Photo by NASA / USGS)

The gray and white spots between the pink sands are plain covered with dry salt. The temperature in Rub al-Khali (literally translated as “empty quarter”) reaches 54 ° C. In such a heat can survive only some species of plants, spiders and rodents living here. Sand covers one of the most oil-rich areas in the world.

This photo was taken in 2001. using Enhanced Thematic Mapper Plus (ETM +) on Landsat 7 satellite owned by NASA / USGS. Below you can look at a picture of the dunes near. Learn more about Rub Al Khali from this National Geographic video.

Tifernain Dunes in Algeria

Look at Yandex. Photos (Photo by NASA)
This part of the Sahara Desert, located in the east of Algeria, adjoins the dark gray plateau of Tinrchert. Over the old large dunes, star dunes formed under the action of winds, and sedimentary rocks along with salt gathered in small hollows between the dunes. Today's climate is dry and hot, but the valleys hewn by rivers on the plateau border indicate a more humid climate in the past.

This photo was taken by astronauts from the ISS in August 2009.

Unyanga Lakes, Chad

Look at Yandex. Photos (Photo by NASA)
These finger-shaped lakes are echoes of a single large lake, which began to decrease about 5.5 thousand years ago. The sand was blown in by the wind, partially filling the lake basin and breaking water into several separate lakes. Nine out of ten lakes are fresh, they draw water from the aquifer under the ground. Ancient pollen found among sedimentary rocks in lakes showed that the area they occupied used to have a moderately tropical climate.

This photo was taken by astronauts of the ISS on November 14th.

Highest oldest dunes in the world

Look at Yandex. Photos
In the Namib desert you can find dunes with a height of about three hundred meters. They were carved by the winds blowing along the Atlantic coast of Namibia. Namib Naukluft National Park, pictured here, is one of the largest game parks in Africa. Hyenas, jackals, geckos and other rare animals found shelter in it. In addition, this desert is considered one of the oldest in the world - the climate here was dry 55 million years ago. Today, its area receives an average of only 6 cm of rain per year.

The picture above was taken in 2000 by the Landsat-7 satellite, which was operated by NASA and the USGS (US Geological Survey). The topographic image below was created by combining a photograph taken in 2002 with topological data obtained by ASTER equipment from the Terra satellite. In 2009, he celebrated his tenth anniversary.

Look at Yandex. Photos

Colorado Great Sand Dunes

Look at Yandex. Photos
This collection of dunes perched near the Sangre de Cristo Mountains in southern Colorado was granted the status of a national monument in 1932 and a national park in 2004. Every year it is visited by 300 thousand visitors. Despite the fact that these dunes cover an area of slightly less than 80 square kilometers, they reach 230 m in height and are the highest dunes in the United States.

The slightly colored sand of the dunes was formed from sedimentary rock, which gradually eroded from the surrounding mountains and settled in the lake. The lake periodically dried up, and the wind blew the rock from its bottom.

A photograph of the Great Sand Dunes National Park (above) was taken by the Ikonos sensor onboard the GeoEye satellite in 2005. Below is a photograph taken by astronauts of the ISS in 2007.

Look at Yandex. Photos

Saktoria: Ciliates who lose their cilia

Look at Yandex. Photos
Smooth, almost flatless, flat-bottomed bowls, bordered by huge dunes, which in turn are covered with small toothed dunes, give the honeycomb look to the central part of the Sahara desert.
The sandy Murzuk sea in Libya contains numerous rows of such large dunes, called “draa”. The smaller dunes, which can be seen in the photo below, consist of many star dunes, linear longitudinal dunes and curved transverse dunes. The weathered side of smaller dunes is smoother and flatter than the opposite side. This photo was taken by astronauts of the ISS in December 2008.

Look at Yandex. Photos

Lake Eyre in Australia

Look at Yandex. Photos
Heavy rains in early 2009 began to fill this huge bottom of a dry lake in this part of the Simpson Desert in Queensland. In the photo above you can see the water flowing into the lake. It was made on May 9 by Landsat-5. Plants and thousands of birds appear along with the water. The photograph below, which was made by satellite on February 18, shows how dry this area remains most of the time in the year.

Look at Yandex. Photos

Nude rocks in the Sahara

Look at Yandex. Photos
Sandy rivers, sheltered by dunes, bend around nude rock in this very arid and barren section of the Sahara in Libya. This photo was taken by satellite Terra in 2002.

Scars of australia

Look at Yandex. Photos
This part of the Simpson Desert in the Northern Territory of Australia is covered with desert shrubs, which gives it a greenish tint and does not allow the winds to dislodge the dunes. However, the fire that occurred here a year before this photo was taken in 2002 burned part of the vegetation, exposing the sands under it.

The strange pattern in the sand must have been caused by a 90 degree rotation of the wind direction during a fire. This photo was taken by ISS astronauts.
Sandy rivers, sheltered by dunes, bend around nude rock in this very arid and barren section of the Sahara in Libya. This photo was taken by satellite Terra in 2002.