ISS063-E-88524

Browse image
Resolutions offered for this image:
5568 x 3712 pixels 720 x 480 pixels 5568 x 3712 pixels 640 x 427 pixels
Cloud masks available for this image:

Spacecraft nadir point: 47.2° S, 68.2° W

Photo center point: 47.4° S, 71.9° W

Nadir to Photo Center: West

Spacecraft Altitude: 229 nautical miles (424km)
Click for Google map
Width Height Annotated Cropped Purpose Links
5568 pixels 3712 pixels Yes No Download Image
720 pixels 480 pixels Yes No Download Image
5568 pixels 3712 pixels No No Download Image
640 pixels 427 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:

An astronaut onboard the International Space Station shot this photograph of Lake Pueyrredón and Lake Posadas in the Patagonia region of southern Argentina. Snow-covered foothills of the Andes Mountains appear along the lower margin. Streaks on the lake surface are produced by the strong winds that are very common in the region. The dark shadow of a cloud falls on the surface of Lake Posadas. Though the permanent population is small, tourism brings many people to Patagonia’s lake region; the small airstrip and lakeside road aid with arrivals.

Rivers from the local hills have dumped sediment on the shores of the lakes to form small deltas. Three are prominent on the shore of Lake Pueyrredón. (To the west in Chile, Lake Pueyrredón is known as Lake Cochrane.) Very strong and persistent winds have generated waves and currents powerful enough to erode sand from the toes of the fan-deltas, creating long, thin sand spits pointing down-current.

The biggest delta is connected to the opposite shore by a sand bar 3.5 kilometers (2.2 miles) long; it actually may be an ancient moraine. This sand bar cut off the eastern end of Lake Pueyrredón to form the smaller Lake Posadas. Posadas is lighter in color because of the light-toned sediment flowing into it from the incoming river.

Land surfaces here have been dynamic in the past one or two million years. Geologists now know that ice sheets that formed along the nearby Andes Mountains have expanded repeatedly, each time covering almost the entire area shown in the photo. Other astronaut photos such as this one show the Northern Patagonian ice sheet that affected Lake Pueyrredón.