Project Twinkle was an investigation, begun in 1950, into reports, from late 1948 to 1951, of the appearance of green "fireballs" in the general area of Holloman Air Force Base and Vaughn, New Mexico. It was conducted by the Air Materiel Command (AMC) and Air Research and Development Command (ARDC) and headed by Lincoln La Paz, a meteor specialist, who became convinced that the fireballs were not natural phenomena. However, as a memo to the Commanding General of AMC, dated 15 September 1950, points out "It may be considered significant that fire balls have ceased abruptly as soon as a systematic watch was set up."