Standing watch over the antennas of the Atacama Large Millimeter/submillimeter Array (ALMA), Orion, the Hunter, shines high in the Chilean night sky.
With its distinctive hourglass shape and the three bright stars of Orion’s Belt in the centre, the constellation is easily recognisable. Taken from the southern hemisphere, this image shows Orion’s sword above the Belt. The sword is home to one of the most stunning features of the sky — the Orion Nebula — which appears as the middle “star” in the sword, its fuzzy nebulosity visible to the naked eye under good conditions.
The three ALMA antennas visible in the image represent only a small part of the complete ALMA array, which has a total of 66 antennas. ALMA combines the signals from its antennas, separated over distances of up to 16 kilometres, to form a single giant telescope, using a technique called interferometry.