Eyes on the Skies

Pictured here are several of the radio telescopes comprising the Atacama Large Millimeter/submillimeter Array (ALMA). ALMA studies the Universe in wavelengths invisible to the human eye. Above the antennas, intricate dust clouds weave through the Milky Way. The prominent diamond shape of the Southern Cross (Crux) shines above the middle antenna, bordered on the left by a dark, dusty patch that blocks out the stars behind it. This is the Coalsack Nebula, also known as the head of the Emu in the Sky, an ancient constellation known to Aboriginal Australians. In front of this nebulous region are two bright stars: Alpha and Beta Centauri, both triple star systems where three stars are bound together by gravity.