A global network of millimetre and submillimetre telescopes to study black holes. Its largest and most sensitive member is the Atacama Large Millimeter/submillimeter Array (ALMA). EHT forms an Earth-sized very long baseline interferometer with the resolution to discern details of the event horizon around the supermassive black holes at the centre of our Galaxy and the giant elliptical galaxy M87. EHT’s headquarters are at the Haystack Observatory, Massachusetts.
http://www.eventhorizontelescope.org Project website with full list of collaborating members.