The Captain of the United Airlines Boeing 737 that diverted to Salt Lake City on Thursday says his plane was hit by space debris. JonNYC was first to report this theory, along with photos of damage to the cockpit’s windshield and photos of the captain’s arm that sustained an injury.
I was initially skeptical of space debris as the explanation for damage to Flight 1093 from Denver to Los Angeles with 140 passengers on board only because of how low probability an event that would be. Individual passenger casualty risk from space debris has been deemed less than a trillion‑to‑one event by the FAA. Photos made clear that it was impact of some kind, rather than thermal stress of the windshield.
Here are more photos, showing the full windshield as well as debris in the cockpit:
HOLY CRAP!!! A MAX8 hit a falling object at FL360 yesterday!!! pic.twitter.com/OBx8eUiq4w
— Oeingo Boeing-Go (@oeingoboeing) October 18, 2025
The captain reportedly stated that the impact appeared to be from space debris. Space debris refers to defunct human-made objects in Earth’s orbit—such as inactive satellites, spent rocket stages, and fragments from collisions or explosions—that no longer serve a purpose and may remain in orbit or eventually fall back into Earth’s atmosphere.
These can be like loose pebbles hitting your windshield on the highway, and they pose significant risk to spacecraft and satellites.
It was posted the CA stated he saw it coming at the last moment and that it appeared to him to be “space debris.”
— Oeingo Boeing-Go (@oeingoboeing) October 18, 2025
While damage appears consistent with space debris, perhaps, it still seems so rare (no such incident has ever been recorded) and the report that he ‘saw it coming’ suggests to me that it was something other than space debris.
Space debris would be tiny and dark by the time it reached the plane’s altitude, and wouldn’t reflect much light, likely blending into the sky. It would be moving incredibly fast. By the time it’s close enough to see, it would already hit — we’d be talking a fraction of a second between being visible and impact at most. And cockpit windows only show a small slice of sky. The captain would have to have been staring at exactly the right spot at exactly the right time to see it.
The odds of space debris are low. The odds of seeing the space debris if that’s what it was are low. So while it may have been ‘something like’ space debris, and I am fascinated to continue following this story, I remain skeptical of that particular explanation. Luckily, the plane diverted safely and passengers were ferried on to L.A. on another aircraft.
How would glass enter the cockpit if only the outer layer shattered?
Send Elon Musk the bill.
But getting hit by space debris will definitely get him more social media hits.
Sure it wasn’t one of those Chinese spy balloons? High tech!
Like that woman in Australia who claimed she was injured by a piece of Skylab?
The models on how much debris would survive atmospheric entry and make it to the ground (which 36k feet is “the ground” for the purposes of this discussion) have been proven incorrect repeatedly over the last couple of years or so. SpaceX has put up enough material that we’re starting to see where it lands when it makes an uncontrolled reentry even after it was determined that it would burn up.
Significant (as in, could def easily have killed someone) chunks landing in NC woods:
https://www.space.com/nasa-confirms-debris-spacex-crew-dragon
Small but potentially lethal chunk that landed in a FL home, while a child was there (not SpaceX this time):
https://www.space.com/space-debris-florida-family-nasa-lawsuit
Car damage reported in Turks and Caicos after SpaceX Starship failure:
https://www.usanewsindependent.com/stories/regulators-are-investigating-reports-of-property-damage-from-spacex-starships-explosion-2664/
Anyway, I wouldn’t trust a 1T:1 odds as being correct. Doesn’t make it space debris, just don’t trust those numbers.
Space debris at cruising altitude doesn’t travel particularly fast. Think of a bullet that’s been fired at a shallow angle into a swimming pool. The water is the atmosphere. The bullet is the debris. The plane is flying a few inches above the bottom of the pool. By the time the bullet gets there, its initial velocity has been violently stopped by the ‘impact’ with the water, and it’s actually gently sinking vertically at terminal velocity. So it makes sense that that a piece of debris would hit the front of the aircraft (the speed of the impact is actually the plane’s forward speed) and that the pilot might have time (albeit barely) to see that they’re flying straight at something, a bit like flying into a goose.
How can you measure the odds of something if it has never happened before?
@Mike — It’s kinda like the show ‘Who’s Line Is It Anyway?’ where the points don’t matter and nobody cares… guess-timate!
@AnAerospaceEngineer’s explanation is helpful (and sorry, I trust his expertise more in this case than GL’s- so it sounds like space debris is plausible) but I also saw coverage saying it may have been hail. The pictures do look like a chunk of something that could be a huge chunk of hail if not debris- but then again I would assume if it was hail it would more likely have been part of a detectable storm he was flying through. Not sure whether there were storms in the area and what the chances are of a “rogue hailstone”.
You are unlikely to see a piece of falling space debris on a trajectory that doesn’t intersect your position. But if it’s coming right at you, then it hold relatively still in your field of view, growing larger until impact. While highly unlikely, the incident as described fits the space debris explanation. What else could be falling at that altitude? Not a lot of options.
Hail seems much more likely. Will be interesting to see weather radar images from the region at the time and if there were any other dings on the radome, fuselage, or wings. Space debris seems like a long shot, although something reentered the atmosphere “fairly close” to our aircraft, and through our altitude, on a daytime return trip from Hawaii along a published track just a couple years ago. It was probably 40 miles away, but definitely caught our attention. We reported it through safety channels, but never heard back.
The windshield and the captain’s skin abrasions look very similar to a bird strike I had years ago during a military low level flight. The impact was centered in the window a few feet in front of me. The inner windshield pane exploded like a shotgun blast of rock salt, and the outer pane remained intact, although shattered into tiny pieces and bowed into the cockpit. The volume of glass completely covered the center console so that I had to dig to get to the radio controls. I received similar abrasions, mainly from the force of the flying glass, with a few bruises on my chest. My helmet visor and metal parachute harness were severely pitted by the flying glass. Airspeed was 350 mph.
So, the photos and results of the recent Delta incident are entirely believable to me. Hopefully, more information will be available about the object in the coming weeks.
Almost certainly not hail.
WindBorneWX weather balloon is the most likely culprit. Right altitude and uses sand as ballast.
https://x.com/djsnm/status/1980433951551533203?s=46&t=3_r1gt-xiHSIYDCbpY59OA
@Giuseppe B. – indeed, they are taking responsibility and I have written this post!
Fellas, well, well, well… woncha lookie here…
1990 says:
October 18, 2025 at 4:12 pm
“Sure it wasn’t one of those Chinese spy balloons? High tech!”
Turns out, per Gary’s separate later post today, 10/21/25, on this topic, it was indeed a balloon… a weather balloon… and, you know, who’s to say it wasn’t funded (covertly) by the CCP… hmm.
*Roll Safe (the Guy Tapping His Head) meme*