Skylab's Three Crews, and the Lights They Couldn't Explain

Skylab flew three crews between 1973 and 1974. In their post-flight technical debriefings - transcribed and preserved on the record, not filed as UFO reports - all three crews described unexplained light phenomena: flashes seen with eyes closed, a bright reddish object tracked for minutes on end, and flashing lights moving independently outside the station. Here is what the astronauts actually said, in their own words.

What this document is

Skylab was the United States' first space station, launched on May 14, 1973, and occupied by three successive three-man crews over the following year: Skylab 2 (Pete Conrad, Paul Weitz, Joseph Kerwin), Skylab 3 (Alan Bean, Owen Garriott, Jack Lousma), and Skylab 4 (Gerald Carr, William Pogue, Edward Gibson). NASA-UAP-D007 is not a single report written about a single event. It is a set of excerpts pulled from all three missions' technical crew debriefings - the standard post-flight interview NASA's Training Office conducted with every crew, covering everything from hardware performance to medical kits to, in these three instances, things the crew saw out the window that nobody could identify.

The debriefings themselves are dated June 30, 1973 (Skylab 1/2, meaning the debriefing following the Skylab 2 mission), October 4, 1973 (Skylab 1/3), and February 22, 1974 (Skylab 1/4). Each carries the header "This document may be exempt from public disclosure under the Freedom of Information Act (5 U.S.C. 552)" - standard boilerplate on NASA internal debriefing transcripts of that era, not a marker of unusual sensitivity. These are working transcripts of crew debriefs, released decades later as part of the PURSUE disclosure.

What makes the document useful is also what limits it: these are transcripts of a group conversation between named crew members and a debriefing officer, not an investigative report. Nobody in the room is trying to identify the lights. The crew describes what they saw, sometimes speculates briefly, and the conversation moves on to the next agenda item - medical kits, heat exchangers, EVA anomalies. The document preserves the observations. It does not resolve them.

Skylab 2: "We saw light flashes"

The debriefing for the first crew - Pete Conrad (commander), Paul Weitz (pilot), and Joseph Kerwin (science pilot) - includes a segment on page 23-20 labeled "Unusual or Unexpected Visual Phenomenon." Kerwin, the science pilot, opens it:

"We saw light flashes. I think all of us saw them. I saw them most often when I was in the sack at night with my eyes closed but awake naturally. They tended to wax and wane in frequency. Someone asked me if that was in conjunction with the South Atlantic anomaly. It may have been. I didn't have the pad with me at that time and I don't know. They were numerous at times - two or three per minute."

This is a description of what would later become a well-studied phenomenon in spaceflight medicine: astronauts perceiving flashes of light with their eyes closed, generally attributed to cosmic ray particles interacting with the retina or optic nerve, often more frequent over the region of Earth's magnetic field called the South Atlantic Anomaly where charged particles dip closer to the atmosphere. Kerwin himself raises that exact hypothesis in the transcript - "Someone asked me if that was in conjunction with the South Atlantic anomaly" - which tells you the crew and ground team already had a working theory in 1973, years before the phenomenon was formally named and studied in later Apollo and Skylab literature.

What follows in the transcript is a genuinely interesting piece of on-the-record cross-talk between all three crew members, comparing notes on the flashes' character:

"Some of them to me were a spot or sunbursts. Some were streaks. The streaks, in my case, were less frequent than the bursts. Most of them were in my peripheral visual field. Very few in the central visual field. I don't know why." - Conrad

"I would say mine were primarily in the left eye for some reason." - Weitz

Kerwin is asked directly whether the flashes could be isolated to one eye. He says he didn't try to check, but adds a line that reads almost as a pre-emptive rebuttal to any suggestion the flashes were imagined: "They're not an hallucination." The crew goes on to distinguish the flashes from an unrelated, mundane phenomenon - a fire sensor light blinking, which Conrad says he sometimes confused with "the fire flash" when half-asleep - and from what Weitz describes as "cosmic particles," entrance and exit streaks crossing the eye "bing-bing... one side of the eyeball, and then the other side."

Read in full, the Skylab 2 segment is best understood as the astronauts and debriefing officer jointly describing and characterizing a subjective visual phenomenon they already suspected was radiation-related, not as an unidentified object sighting. It is included in the PURSUE archive because it is a documented instance of crew-observed light phenomena in the NASA UAP release, and the site includes it on those terms - not because the transcript itself frames it as anomalous.

Skylab 3: the reddish object that matched their orbit

The second crew's debriefing (Alan Bean, commander; Owen Garriott, science pilot; Jack Lousma, pilot) contains a different kind of observation: not a subjective light-flash phenomenon, but a discrete, tracked, external object. It comes up twice in the transcript, once informally on page 7-4 and again more precisely under a dedicated "20.0 VISUAL SIGHTINGS" section on pages 20-1 and 20-2.

The first mention, from Garriott, on page 7-4:

"For example, we saw that satellite about a week before splashdown. That was one of the most unusual things that we saw and I guess Jack noticed it looking out the window. This bright reddish object was out there and we tracked it for about 5 or 10 minutes. It was obviously a satellite in a very similar orbit to our own. It was rotating and had a period of almost exactly 10 seconds because you could see the brightness vary with that period. We followed it until sunset and it went out of sunlight just about 5 to 7 seconds after we did. It held its position nearly the same, in the wardroom window for that 10-minute interval although we could see it drift in relative positions slightly, maybe 10 to - 20 degrees during the course of that 10-minute interval. It was reddish in color even when we were well above the horizon. As we approached sunset, it turned more reddish, presumably because of the sunlight change. What satellite it was and how it happened to end up in such a similar orbit, no one ever explained to us. And I would like to hear a few words from someone about that satellite."

Bean, the commander, follows with a detail worth noting: they never saw it again, despite expecting a repeat pass. "You bet. We never saw it again. You'd think we would have seen it the next night or it would cycle by another time. Maybe it did and we weren't looking out the window." Lousma adds a specific, testable observational detail: "You might point out that it never did take the shape of an object but it was always brighter than any other star or planet in the night sky. It was much brighter." Bean confirms the crew tried to resolve it further and could not: "We tried monitors and everything on it but we could never make it into anything other than a bright light."

The transcript's dedicated visual-sightings section, later in the same debriefing, returns to the same object with more precision - including an estimate of range derived from the light-travel delay into Earth's shadow. This is Garriott again, on pages 20-1 and 20-2:

"Jack first noticed this rather large red star out the wardroom window. Upon close examination, it was much brighter than Jupiter or any of the other planets. It had a reddish hue to it, even though it was well above the horizon. The light from the Sun was not passing close to the Earth's limb at the time. We observed it for about 10 minutes prior to sunset. It was slowly rotating because it had a variation in brightness with a 10-second period. As I was saying, we observed it for about 10 minutes, until we went into darkness, and it also followed us into darkness about 5-seconds later. From the 5- to 10-second delay in it's disappearance we surmised that it was not more than 30 to 50 nautical miles from our location. From it's original position in the wardroom window, it did not move more than 10 or 20 degrees over the 10 minutes or so that we watched it. It's orbit was very close to that of our own. We never saw it on any - earlier or succeeding orbits and we'd be quite interested in having its identification established."

That is a technically specific account: a rotating object with a consistent ~10-second brightness period, tracked for roughly ten minutes, estimated (by the crew's own light-delay reasoning) to be within 30 to 50 nautical miles, in an orbit close enough to Skylab's own that it stayed in the same window for the entire observation. Lousma, elsewhere in the same section, distinguishes it from routine satellite sightings: "I saw a couple of satellites that appeared like a satellite would on the Earth. I saw one that was not like one you would see on Earth, so why don't you mention it." The crew explicitly asks, on the record, for someone to identify what it was - "we'd be quite interested in having its identification established" - and the transcript does not record an answer.

The most reasonable reading is that this was very likely some form of orbital debris or a companion object from the Skylab or Saturn launch stack, given the near-identical orbit, the brightness, and the rotation-driven periodic flare, all of which are consistent with a tumbling metallic object reflecting sunlight rather than a light source with its own periodicity. But the transcript itself does not supply that identification. The crew asked for one and, on this record, never got it.

Skylab 4: flashing lights with "a definite motion relative to ours"

The third and final crew's debriefing (Gerald P. Carr, commander; William Pogue, pilot; Edward Gibson, science pilot) includes a shorter observation, on page 7-8, offered by Carr in a segment about "unusual events" reported on the mission's data dump tapes:

"One other area of unusual events that we reported on the dump tapes was that on occasion we saw some lights flashing outside with very a definite motion relative to ours. We presumed that they were other pieces of Skylab, or possibly other satellites. We reported our two or three sightings of that kind as soon as they occurred. We have no special comments concerning them, but we did find it very interesting to be able to see other objects up there with us. The fact that one or two of them appeared to be tumbling was apparently due to the oscillation of the light flashes that we were getting from them."

This is the most self-resolving of the three accounts. Carr offers the crew's own working explanation in the same breath as the observation: debris from Skylab itself, or other satellites, tumbling and producing an oscillating flash pattern as reflective surfaces caught and lost sunlight. He states plainly that the crew had "no special comments concerning them" beyond finding it interesting to see other objects nearby. Of the three debriefings excerpted in this file, this is the one where the crew volunteers a specific, physically ordinary mechanism (tumbling debris catching sunlight) and treats the matter as closed.

What ties the three accounts together, and what doesn't

It would overstate the document to treat these as three versions of the same event. They are not. The Skylab 2 flashes are a subjective, eyes-closed visual phenomenon the crew themselves suspected was radiation-related. The Skylab 3 object is an external, tracked, unexplained point of light with specific orbital characteristics the crew wanted identified and apparently never had confirmed on the record. The Skylab 4 lights are external flashes the crew explained to their own satisfaction as tumbling debris. Lumping all three together as "Skylab UFOs" would be the kind of loose, unverifiable framing this site avoids.

What does tie them together is more modest and, in a way, more useful: all three of Skylab's crews, independently, across missions eight months apart, used their post-flight technical debriefings to put unusual light observations on the permanent NASA record, even when (as with Skylab 4) they had a ready explanation, and even when (as with Skylab 3) they didn't. That is a pattern of institutional candor worth noting on its own terms - three separate crews, in the normal course of routine debriefing, chose to describe things they saw and, in the Skylab 3 case, explicitly said they wanted an answer they didn't get.

Why 59/100

The Anomalousness Index scores NASA-UAP-D007 at 59/100. The witness-credibility component is scored highest (astronaut, professionally trained observers under debriefing conditions where inflating a claim carries career risk, not reward). The corroboration component reflects that these are largely single-witness-instrument observations - the human eye, without instrumented backup - though multiple crew members on Skylab 2 independently described the same flash phenomenon, and both Garriott and Lousma discussed the same Skylab 3 object. The sensor-quality component is capped low because none of the three observations includes photographic, radar, or instrumented data; everything here is descriptive testimony. The kinematic-anomaly component is flagged "no kinematic data" because, aside from the crew's own rough range estimate on the Skylab 3 object, there is no independently verified speed, altitude, or maneuver data. The mundane-explanation-available component is scored as a "weak mundane candidate": cosmic-ray retinal flashes are a well-documented, physiologically explained phenomenon for the Skylab 2 segment, and tumbling debris is a plausible, crew-offered explanation for Skylab 4 - but the Skylab 3 object, as transcribed, was never identified in this document, which is why the mundane candidate is scored weak rather than strong across the file as a whole.

How to verify everything on this page

1. Every quoted line above is transcribed verbatim from the OCR-extracted text of NASA-UAP-D007, linked above, and is attributed to the specific crew member the transcript names (Kerwin, Conrad, Weitz on Skylab 2; Garriott, Lousma, Bean on Skylab 3; Carr on Skylab 4).
2. Kerwin's "light flashes" quote is on page 23-20 of the Skylab 1/2 debriefing (document page 2 of the combined PDF).
3. Garriott's first "reddish object" account is on page 7-4 of the Skylab 1/3 debriefing (document page 5); the more detailed tracking account with Garriott and Lousma is on pages 20-1 and 20-2 (document pages 7-8).
4. Carr's "flashing... relative to ours" quote is on page 7-8 of the Skylab 1/4 debriefing (document page 10).
5. The South Atlantic Anomaly and cosmic-ray retinal-flash phenomenon referenced by Kerwin is a documented spaceflight-medicine subject independently discussed in later NASA and Apollo literature; this page does not assert NASA confirmed the cause in 1973, only that Kerwin raised the hypothesis in the transcript itself.
6. The 59/100 score and component breakdown are reproducible from this site's open rubric.