ALMA's gemelas

An image of ALMA's antennas on snow Chajnantor Plateau in Chile's Atacama Desert. The 66 antennas come in two sizes, 54 with a 12-metre diameter dish and 12 with a smaller 7-metre dish, but they work together as a seamless team to act as one telescope. They can be spread up to 16 kilometres apart, in many arrangements that slightly change the telescope's traits, but their data is always combined, using interferometric techniques and a special computer called the ALMA Correlator, to create a single final result. In this way, all 66 are bound together as almas gemelas—or soulmates, in English.