On top of Las Campanas peak, over 2,550 metres (8,500 feet) above sea level in the Atacama Desert, Chile, the next class of terrestrial supertelescope is under construction. The Giant Magellan Telescope (GMT) is being built as part of the US Extremely Large Telescope Program in the same region as a number of other notable telescopes and instruments. Observatories are concentrated in this part of the world because the extremely dry air and low rainfall results in
