[Skip to content]
ISS010-E-13539
Browse image
Resolutions offered for this image:
1000 x 661 pixels 540 x 357 pixels 1000 x 661 pixels 540 x 334 pixels 540 x 357 pixels 3032 x 2064 pixels 639 x 435 pixels

MAP LOCATION
latitude/longitude of image
Spacecraft nadir point: 36.7° N, 19.4° E

Photo center point: 26.8° N, 7.3° E

Nadir to Photo Center: Southwest

Spacecraft Altitude: 188 nautical miles (348km)
Click for Google map
IMAGE DETAILS
features and other details
CAMERA INFORMATION
information about camera used
ALL DOWNLOAD OPTIONS
additional formats
Width Height Annotated Cropped Purpose Links
1000 pixels 661 pixels No Yes Earth From Space collection Download Image
540 pixels 357 pixels Yes Yes Earth From Space collection Download Image
1000 pixels 661 pixels No Yes NASA's Earth Observatory web site Download Image
540 pixels 334 pixels Yes Yes NASA's Earth Observatory web site Download Image
540 pixels 357 pixels Yes Yes NASA's Earth Observatory web site Download Image
3032 pixels 2064 pixels No No Download Image
639 pixels 435 pixels No No Download Image
Other options available:
Download Packaged File
Download a Google Earth KML for this Image
View photo footprint information
Image Caption: Issaouane Erg, Algeria

The Issaouane Erg (sand sea) is located in eastern Algeria between the Tinrhert Plateau to the north and the Fadnoun Plateau to the south. Ergs are vast areas of moving sand with little to no vegetation cover. Considered to be part of the Sahara Desert, the Issaouane Erg covers an area of approximately 38,000 km2. These complex dunes form the active southwestern border of the sand sea.

The most common landforms in the image are star dunes and barchan (or crescent) dunes. Small linear dunes appear at top left. Star dunes are formed when sand is transported from variable wind directions, whereas barchan dunes form in a single dominant wind regime. The superimposition of two dune types suggests that wind regimes have changed through time. The active nature of this portion of the Erg is well illustrated by this image--smaller dunes form and migrate along the flanks of the larger dunes and sand ridges. Occasional precipitation fills basins formed by the dunes; as the water evaporates, salt deposits are left behind which appear as bluish-white areas.