Atacama Large Millimetre/Submillimetre Array (ALMA)
From the European Southern Observatory, this video describes ALMA, the largest astronomical project currently being built.
ALMA is a state-of-the-art telescope to study light with wavelengths of about one millimetre, shining from some of the coldest objects in the Universe. It is a cooperation of the European Southern Observatory (ESO), together with its international partners.
The site of ALMA is the 5000m altitude Chajnantor plateau in northern Chile, one of the driest places on Earth.
More videos can be seen on the ESO website.