Thermopolis, WyomingOctober 1957

Insufficient Data

Summary

On the night of October 10-11, 1957, a bright fireball streaked across the sky over northeastern Utah and Wyoming, spotted by military pilots, ground observers, and civilians across a wide area. The object appeared as a round ball with a long, flaring tail that glowed white and blue with flashes of red. It moved west-southwest in a straight line with occasional bursts of speed, burning brightly enough to light up the ground below. Witnesses reported the fireball lasted between one and two and a half minutes before it disappeared.

The sighting got attention quickly because it happened just days after the Soviet Union launched its Sputnik satellite, raising fears about what had entered American airspace. Military aircraft at high altitudes saw the object clearly. The U.S. Air Force's 1006th Air Intelligence Service Squadron investigated on the ground in the Utah area, interviewing about twenty witnesses by telephone and in person. A Navy pilot pinpointed where he saw the object strike the ground. Despite this specific location, local sheriffs from Duchesne and Uintah counties conducted both air and ground searches with no results.

The Air Force investigators concluded that the object was definitely a fireball meteor, not wreckage from the Soviet satellite or any other spacecraft. They determined it disintegrated before hitting the ground, which explained why searchers found no pieces of it. The case file notes that the one exception to this conclusion was the Navy pilot, who believed he saw the object strike the earth. The investigators closed the case with no further action planned, unless debris was later discovered in the area.

The full case file, held by the National Archives, is reproduced below in 12 pages.

Reported location

Thermopolis, Wyoming

Date of incident

October 1957

State / country

WY / US

Page count

12 scanned pages

USAF evaluation

unknown

Microfilm

T1206, Roll 29

" 11:12 5 EE HT TETRIS SAN I RENOIR. Ne J Te TT pe + 4 ree og meer jamin 4 PROJECT: 10073 RECORD CARD HB [1 pare : 2. LOCATION 12. CONCLUSIONS : Thermopolis, Wyoming O Wes Bolloon | 10 October 1957 Myton, Utah Western U.S. DO Probebly Bolleon 3. DATE-TIME GROUP 4 TYPE OF OBSERVATION § Petiiwy Buiieen | . O VWos Aircraft Leesl approx 4:15 MST 38 Ground-Vi sual D Ground-Reder 0 Probobly Aireroft | GM OV RIDeR 0 Air Visvel O Air-Intercopt Rodor O Possibly Aircraft 15 ve f » SOUR XTX Was Astronomicol Firebal OVYes O Probably Astronomical 3DXNe Various/military & civilian |D Possibly Astronomical | | 7. LENGTH OP.OBSERVATION 8. NUMBER OF OBJECTS | 9. COURSE ID I, 5 eat ong Date for Evaluation 1 to 45 deconds one W - 8W op 10. BRIEF SUMMARY OF SIGHTING 1). COMMENTS Large brilliant blue-white flaming This sighting resulted in creat- object observed in Myton, Utah & other] ing nation-wide attention to the widely separated areas, Sighted by incident, following on the heels Navy and Air Force pilots also. The of the Satellite launched only a former stating that it narrowly missed few days before by the Soviets, {ll his aircmaft, Obj rptd as having a Obj was a rarely seen form of blue-$lamed tail, meteorite, a fireball, : | . ATIC PORM 329 (REV 26 SEP 82) 3 | | y ; 1 . Fy A pi ji ETE EEN SIERRA ERE AREA SOS shes Le Es a ; |