A worker prepares a parabolic antenna of the ALMA (Atacama Large Millimetre/Submillimetre Array) project at the El Llano de Chajnantor in the Atacama desert, some 1730 km north of Santiago and 5000 metres above sea level, March 12, 2013. ALMA will be inaugurated on Wednesday and is being constructed by the ESO (European Organisation for Astronomical Research in the Southern Hemisphere) with its partners NAOJ (National Astronomical Observatory of Japan) and NRAO (National Radio Astronomy Observatory). ALMA will have 66 high precision antennas which will work together as a single giant telescope to study the universe, molecular gas, dust of stars, galaxies and planetary systems, ESO said. [Photo/Agencies]