Alma Observatory (IMAGE) KU Leuven Caption ALMA is the world's largest observatory at millimetre wavelengths. It is installed on the high-altitude plateau of Chajnantor in the Atacama desert (Chile). It consists of 66 individual radio antennas used jointly to synthesize a giant virtual telescope of 16 km in diameter. Credit © ALMA (ESO/NAOJ/NRAO) Usage Restrictions To be used with appropriate credit only License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.