Haystack Observatory, Massachusetts

The Haystack Observatory is located in a complex of radio antennas in the hills above Westford and Tyngsboro. Inside the facility's dome is a 121-foot-diameter steerable radio dish, which while designed by MIT's Lincoln Lab, was built by the U.S. Air Force. Construction began in 1960, with the radio telescope becoming operational by 1964. In 1970, ownership was transferred from the military to MIT, and the antenna is now used mostly by the Northeast Radio Observatory Corporation (NEROC), a consortium of 12 educational institutions. It is used for astronomical observations by the universities, and for space surveillance and debris tracking by the Air Force.