Distant view of Chajnantor

Sunset over the majestic mountains in the area of San Pedro de Atacama. The grazing sunlight intensifies the red colour of the volcanic rock which characterises the landscape at the intermediate altitude range. From left to right, partially covered by clouds, are the Licancabur and Jurique volcanoes, followed by the “Cerro Toco” and the Chajnantor plateau, hidden behind the high peaks. Due to its elevation (5000 metres above sea level) and its dryness, the Chajnantor plateau is one of the best sites on Earth for millimetre and submillimetre astronomy. It is the home of ALMA, the Atacama Large Millimeter/submillimeter Array, the most powerful radio observatory in the world operating at these wavelengths. Chajnantor is also the home of another submillimetre telescope, APEX, the Atacama Pathfinder Experiment, which has operated there since 2005.