NASA Mercury Astronaut Observations (1961–1963) – PURSUE Files

On the first American orbital flight in February 1962, John Glenn reported glowing “fireflies” drifting around his capsule. Later Mercury pilots saw similar things: Scott Carpenter described reflective particles that looked “exactly like snowflakes” (Aurora 7, May 1962), Wally Schirra saw “little white objects… like lathe shavings” (Sigma 7, October 1962), and Gordon Cooper saw “John’s fireflies” on Faith 7 in May 1963. PURSUE Release 02 published these audio excerpts, and Release 03 added NASA’s file on scientific interest in the phenomenon and a November 1962 interview in which Walter Cronkite asked Cooper about UFOs.^[1]

The records

NASA-UAP-D015, Astronaut Scientific Debriefings, 1962-1963

Open NASA-UAP-D015 (PDF) on war.gov →

This file contains memoranda, correspondence, reports, and other materials relating to contemporary scientific interest in investigating the nature of luminous phenomena reported by astronauts John Glenn and Walter Schirra during spaceflight. This collection includes transcripts from NASA interviews and debriefings with both astronauts regarding those observations. It also contains details relating to scientific observations of atmospheric phenomena, including brief descriptions of luminous particles, experiences while aboard spacecraft, and circa 1955 theoretical analysis of meteoric particles entering the atmosphere. Pages 34-35, 55-56, 57-63, 64-113, and 122-127 feature content relevant to the PURSUE initiative.

— Official PURSUE description

NASA-UAP-D013, Mercury Atlas 7, May 24, 1962

NASA-UAP-D013, Mercury Atlas 7, May 24, 1962 — official upload on DVIDS (public domain).

During the fourth crewed spaceflight and second orbital flight of Project Mercury, Mercury-Atlas 7 (MA-7), Aurora 7 pilot Scott Carpenter describes white particles in view that appear to move at “random” and “look exactly like snowflakes.” He describes these phenomena as reflective, and that some seemed to move faster than the Aurora 7 spacecraft.

— Official PURSUE description

NASA-UAP-D012, Mercury Atlas 8 Audio Excerpt, October 3, 1962

NASA-UAP-D012, Mercury Atlas 8 Audio Excerpt, October 3, 1962 — official upload on DVIDS (public domain).

During the Mercury Atlas 8 mission, Sigma 7 pilot Walter M. “Wally” Schirra Jr. describes observing “little white objects that tend to come from the capsule itself and drift off.” Schirra later also refers to those objects as “particles” and “lathe shavings.” Schirra also describes seeing a burst of light in the window, whose source he cannot identify. He speculates that his observation corresponds with the moment the sun passes below the horizon during sunset.

— Official PURSUE description

NASA-UAP-D010, Mercury Atlas 9 Audio Excerpt, May 15, 1963

NASA-UAP-D010, Mercury Atlas 9 Audio Excerpt, May 15, 1963 — official upload on DVIDS (public domain).

Approximately one hour and 41 minutes into the final and longest flight of Project Mercury, Mercury-Atlas 9 mission (MA-9) Faith 7 Pilot L. Gordon Cooper Jr. notes that he sees “John’s fireflies,” referring to John Glenn’s term from the Mercury-Atlas 6 mission. NASA later determined that the “fireflies” are attributable to frozen condensation separating from the spacecraft body. The white, green-hued appearance of this phenomenon results from sunlight reflecting off frozen condensation.

— Official PURSUE description

NASA-UAP-D011, Mercury Atlas 9 Audio Excerpt, May 15, 1963

NASA-UAP-D011, Mercury Atlas 9 Audio Excerpt, May 15, 1963 — official upload on DVIDS (public domain).

During the final and longest flight of Project Mercury, Mercury-Atlas 9 mission (MA-9) Faith 7 Pilot L. Gordon Cooper Jr. describes the brilliant blue of sunrise beneath the haze layer of the Earth’s atmosphere. As he approaches sunrise, he describes small, luminous, brilliant white particles drifting away from the spacecraft. Cooper describes observing “fireflies” after deploying beacons, which are spherical mission-related equipment with xenon strobe lights.

— Official PURSUE description

NASA-UAP-D014, Mercury-Redstone 4, July 21, 1961

NASA-UAP-D014, Mercury-Redstone 4, July 21, 1961 — official upload on DVIDS (public domain).

During the recovery of the fourth launch and second crewed spaceflight of Project Mercury, Mercury-Redstone 4 (MR-4) Liberty Bell 7, the recovery team discusses a dye pack in the water that did not activate.

— Official PURSUE description

NASA-UAP-D023, Interview Excerpt with Astronaut Gordon Cooper, 1962

NASA-UAP-D023, Interview Excerpt with Astronaut Gordon Cooper, 1962 — official upload on DVIDS (public domain).

In November 1962, journalist Walter Cronkite interviewed astronaut Gordon Cooper. In this excerpt from that interview, Cronkite asks Cooper about his views regarding the nature of unidentified flying objects, having previously expressed an interest in the subject. Cooper opines that “a large number of exceptionally well-qualified people have seen objects” without a “logical explanation” and speculates on the existence of other planets with “a livable atmosphere” and that maybe there are “some type of human life” out there. Interview was conducted in November 1962.

— Official PURSUE description

Analysis

Explanation. During his own flight Carpenter banged on the capsule wall and released a cloud of the particles, which led NASA to conclude they were frost and ice flakes from the spacecraft’s exterior and thruster exhaust, glowing in sunlight; the official descriptions in this release say the same.^[1] This is one of the best-resolved “UFO” observations in spaceflight history.

The Cooper interview. Cooper told Cronkite that “a large number of exceptionally well-qualified people have seen objects” without a “logical explanation.” Cooper remained interested in UFOs all his life and later said he had seen formations of objects as a fighter pilot in 1951; those claims are not supported by records in this release. The Mercury-Redstone 4 clip (a recovery team discussing a dye pack that failed in 1961) has no UFO content.^[2]

New or previously released? Mercury flight audio and the firefly story have been public for decades. The debriefing file and some excerpts appear newly digitized.

Released files

See also

• Gordon Cooper
• John Glenn
• NASA
• NASA Gemini observations
• PURSUE Release 03 (June 12, 2026) overview
• PURSUE Release 02 (May 22, 2026) overview
• PURSUE

Further reading

• James Oberg (1982). UFOs and Outer Space Mysteries: A Sympathetic Skeptic’s Report (Amazon)
• John Glenn & Nick Taylor (1999). John Glenn: A Memoir (Amazon)

References

1. ^ U.S. Department of War (2026). PURSUE Release 03 (June 12, 2026), Release 02 (May 22, 2026): NASA-UAP-D015, NASA-UAP-D013, NASA-UAP-D012, NASA-UAP-D010, NASA-UAP-D011, NASA-UAP-D014, NASA-UAP-D023, with official descriptions. war.gov/ufo.
2. ^ Cooper, G., & Henderson, B. (2000). Leap of Faith: An Astronaut’s Journey into the Unknown. HarperCollins.