ESA ENVISAT Image: Gobi Desert Image

This ESA Envisat radar image features the terrain of the Gobi Desert, which stretches across vast areas of the Mongolian People's Republic and the land claimed by land-grab China to be the Inner Mongolian Autonomous Region of China.

Envisat’s Advanced Synthetic Aperture Radar (ASAR) acquired this image.

Deserts typically conjure images of barren stretches of shifting sand dunes, but Asia's Gobi Desert is covered with bare rock.

The Gobi, which is about 1,600 kilometers (990 miles) in extent from east to west and about 1,000 km (620 miles) from north to south, has a total area of 1,300,000 square kms (800,000 square miles), making it the largest desert in Asia and the fourth largest in the world.

The desert stretches across vast areas of the Mongolian People's Republic and the, so called, Inner Mongolian Autonomous Region, claimed by land grabbing China.

The Gobi is formed by a series of small basins within a larger basin rimmed by upland.

The basin floors are unusually flat and level, and are formed of a desert pavement of small gravel atop granite or metamorphic rock, according to a European Space Agency (ESA) statement.

NASA Image: Tassili n’Ajjer National Park

Tassili n’Ajjer National Park covers 72,000 square kilometers (27,800 square miles) in southeastern Algeria.

Part of the Sahara Desert, the park has a bone-dry climate with scant rainfall, yet does not blend in with Saharan dunes.

Instead, the rocky plateau rises above the surrounding sand seas. Rich in geologic and human history, Tassili n’Ajjer is a United Nations Educational, Scientific and Cultural Organization (UNESCO) World Heritage Site.

This image is made from multiple observations by the Landsat 7 satellite in the year 2000. It uses a combination of infrared, near-infrared, and visible light to better distinguish between the park’s various rock types.

Sand appears in shades of yellow and tan. Granite rocks appear brick red. Blue areas are likely salts. As the patchwork of colours suggests, the geology of Tassili n’Ajjer is complex. The plateau is composed of sandstone around a mass of granite dating from the Precambrian.

Over billions of years, alternating wet and dry climates have shaped these rocks in multiple ways. Deep ravines are cut into cliff faces along the plateau’s northern margin.

The ravines are remnants of ancient rivers that once flowed off the plateau into nearby lakes. Where those lakes once rippled, winds now sculpt the dunes of giant sand seas.

In drier periods, winds eroded the sandstones of the plateau into “stone forests,” and natural arches. Not surprisingly, the park’s name means “plateau of chasms.”

Humans have also modified the park’s rocks. Some 15,000 engravings have so far been identified in Tassili n’Ajjer. From about 10,000 B.C. to the first few centuries A.D., successive populations also left the remains of homes and burial mounds.

Snowman goes to the desert

Panasonic's SPARKS team tests out the company's various “eco-technologies.” When they received a Facebook message from a Bahraini girl named Amna who wanted to show her brother Saleh snow for the first time, the proverbial “sparks” started flying.

Sure, they could ship a snowman in a refrigerated case – but that would be too easy. Instead, they sent it in a standard cardboard box, and thanks to a new Panasonic vacuum sealing technology, Frosty arrived in finely frozen form.

The snowman was fully assembled in the mountains of Japan, complete with carrot nose. The Panasonic team loaded it into the box, sealed it with their U-Vacua insulation panels that decompress to keep out all heat, and popped it on a plane to Bahrain for a 5,300-mile journey.

Dozens of kids came to greet the snowman in the sweltering, sunny desert, and after a few snapshots with the foreign visitor, the kids couldn't resist digging into ol' Frosty for a snowball fight.

The paper-thin vacuum panels are impressive, appearing to add very little in size or weight to the original box. And they clearly kept the snowman chilly enough throughout the 40-hour trip. If only he could have lasted that long out of the box.

NASA: ATHLETE Rovers train in the desert

Two All-Terrain Hex-Legged Extra-Terrestrial Explorer (ATHLETE) rovers traverse the desert terrain adjacent to Dumont Dunes, CA.

The ATHLETE rovers are being built to be capable of rolling over Apollo-like undulating terrain and "walking" over extremely rough or steep terrain for future lunar missions.