Ann Arbor / Dexter-Hillsdale Wave — USAF Swamp Gas Controversy

On the nights of March 20–21, 1966, a wave of UAP sightings swept Michigan. On March 20, Frank Mannor and his son observed a craft low over a swamp near Dexter; Washtenaw County Sheriff's deputies responding to the call also observed luminous objects in the area. The following night, 87 students at Hillsdale College and the college's civil defense director William Van Horn observed a glowing object over a swampy field adjacent to the campus for nearly four hours. The object was described as flat and oval with a bright center, which wobbled and then glided away when police arrived. Across both nights, state police and sheriff's deputies filed formal reports. USAF Project Blue Book dispatched Dr. J. Allen Hynek — its scientific consultant — to investigate. Hynek interviewed witnesses and examined the site. His official explanation, offered at a press conference, attributed the sightings to 'marsh gas' (swamp gas) from decomposing organic matter in the wetlands. The explanation was immediately ridiculed by witnesses and press. Congressman Gerald Ford of Michigan formally demanded a congressional investigation. The backlash led to the formation of the Condon Committee at the University of Colorado (1966–1968), funded by the USAF to provide an independent scientific review of UAP evidence. Hynek himself later publicly expressed regret over the swamp gas explanation and became one of the most prominent scientific advocates for systematic UAP research.