A Gap in the Andes

From 700 kilometers (435 miles) over the Pacific Ocean, an astronaut aboard the International Space Station captured this oblique image of a part of the Andes Mountains. The mountain range crosses the entire image and forms the border between Chile and Argentina’s wine country.

This view is notable because it reveals the canyons and valleys followed by the Pan-American Highway. The spacecraft and Sun were in just the right positions for the Sun’s reflection to illuminate the thin rivers that run through the same deep valley that contains the highway. This pass through the Andes is the main route between Chile’s capital, Santiago, whose outskirts appear in the lower right of the image, and Mendoza, the heart of Argentina’s wine making industry.

The highway route over the Andes starts just north of Chile’s capital city Santiago at the small town of Los Andes and snakes its way up the forested Juncal River valley, where it passes close to Aconcagua, the highest mountain in the Western Hemisphere. Near Aconcagua the highway crosses the international boundary into the Mendoza River valley and passes through a high, treeless desert valley. Then the highway bends southeast and descends to the Mendoza basin, marked here by a blanket of haze. Haze, a variable mix of smoke, dust, and fog, is a typical winter phenomenon on windless days, as seen also in the basins in Chile where Santiago and Los Andes are located.

The Pan-American Highway is an almost continuous road, 30,000 kilometers (19,000 miles) long, that joins seventeen countries in the Americas, from southernmost South America up through North America to the Arctic Ocean.

Astronaut photograph ISS043-E-83229 was acquired on April 2, 2015 with a Nikon D4 digital camera using a 290 millimeter lens, and is provided by the ISS Crew Earth Observations Facility and the Earth Science and Remote Sensing Unit, Johnson Space Center. The image was taken by the Expedition 43 crew. The image in this article has been enhanced to improve contrast. The International Space Station Program supports the laboratory as part of the ISS National Lab to help astronauts take pictures of Earth that will be of the greatest value to scientists and the public, and to make those images freely available on the Internet. Additional images taken by astronauts and cosmonauts can be viewed at the NASA/JSC Gateway to Astronaut Photography of Earth. Caption by M. Justin Wilkinson, Texas State U., Jacobs Contract at NASA-JSC.