Chajnantor panorama

A view across the Chajnantor plain, high in the Chilean Andes, taken from Cerro Chico and looking towards the south, with the Moon visible in the sky. This 5000 metre high, arid plateau is where ESO and its international partners are currently building the Atacama Large Millimeter/submillimeter Array (ALMA), the largest astronomical project in existence. ALMA is a revolutionary astronomical telescope, comprising an array of 66 giant 12-metre and 7-metre diameter antennas observing at millimetre and submillimetre wavelengths. The positions of the 12-metre antennas will be reconfigurable, with almost 200 possible antenna positions spread over 18 kilometres on the plateau. The centre of the ALMA antenna array will be located close to the centre of this image – not far from the technical building visible in the background. The Atacama Pathfinder Experiment (APEX) 12-m submillimetre telescope is seen to the left of the image, in front of Cerro Chascón. The road to the 2,900-metre-high Operation Support Facility is to the right of the image.

An amazing interactive virtual tour is available here