One of the first ALMA antennas on Chajnantor

One of the first ALMA antennas at the Array Operations Site (AOS) in June 2010. The AOS is located at 5000 metres altitude on the Chajnantor plateau, about 50 km away from San Pedro de Atacama, in the II Region of Chile. ALMA will be a single telescope of revolutionary design, composed initially of 66 high-precision antennas. The main array will be composed of fifty 12-metre antennas and the compact array will be composed of four 12-metre antennas plus twelve 7-metre antennas. ALMA, the Atacama Large Millimeter/submillimeter Array, is the largest astronomical project in existence and is a truly global partnership between the scientific communities of East Asia, Europe and North America with Chile. ESO is the European partner in ALMA.