The highest ESO observatory

Footage showing ALMA (Atacama Large Millimeter/submillimeter Array) on Chajnantor Plateau in the Chilean Andes. ALMA is one of the highest observatories on Earth, and focuses on imaging the 'cool' (in temperature) universe–objects like distant galaxies and clouds of gas and dust. These objects are key to understanding our universe, but to observe them well is difficult. Water vapour in Earth's atmosphere interferes with the wavelengths of light ALMA images, so it had to be positioned high under dry skies. Chajnantor is perfect for that, as it's 5000m above sea level under the driest skies outside of Antartica. The ALMA Antennas, as the individual dishes are known, are spread over 16km but positioned to millimetre precision. Together they form one large telescope peering into the mysteries of the universe.