The Michigan 'swamp gas' sightings: mass reports from Dexter and Hillsdale attributed to marsh gas by the Air Force (1966)
A farmhouse family, sheriff's deputies and about 60 people reported a hovering object over marshland near Dexter, Michigan, on the night of 20 March 1966, with a second mass sighting at Hillsdale next day. Air Force investigator J. Allen Hynek attributed both to marsh gas — a verdict widely derided.
- Case number
- TU-1966-900001
- Date
- 21 March 1966
- Location
- Dexter, Washtenaw County, Michigan, USA
- Coordinates
- 42.336° N, 83.886° W
- Shape
- other
- Colour
- Unknown
- Witnesses
- 60
- Status
- explained
Case summary
On the night of 20 March 1966, amid a flap of UFO reports across southern Michigan, farmer Frank Mannor, his wife and son reported a light descending towards marshland near Dexter, Washtenaw County. Mannor telephoned law enforcement and deputies walked into the swamp to investigate. The Mannors said they approached within about 500 yards of a football-shaped object with a 'waffled' texture, blinking lights and antennae, which disappeared, reappeared elsewhere, then departed with a sound compared to a ricocheting rifle bullet. Some twelve law-enforcement officers reported seeing the object, and about 60 people were recorded as witnesses overall.
The following night around 9 p.m., some 87 residents of a Hillsdale College residence hall reported flashing lights above the campus arboretum; county civil defence director William Van Horn watched through binoculars for about three hours, and two Hillsdale police officers also reported observations.
Air Force consultant J. Allen Hynek visited Dexter and, at a Detroit press conference on 25 March, credited marsh gas for the Dexter and Hillsdale landings. The explanation met near-universal hostility; congressman Gerald Ford called for a congressional investigation, and on 6 April Hynek testified to the House Armed Services Committee, breaking with the Air Force line by suggesting some reports merited study. Hynek later said he had used the swamp gas label for only two landing reports within a wider flap.
Nearby strategic sites
- Cape Cod Space Force Station — 1103 km away