Five extremely faint “pinprick” bursts of light flickered across the dark face of the Moon on April 6, 2026, while Orion was about 46,000 miles away. Three Artemis II astronauts logged them by eye during the Sun’s 54-minute eclipse behind the Moon. NASA’s preliminary lunar science report calls them rocky fragments striking the surface, with no atmosphere to burn the debris up first.
The agency’s wording is carefully hedged: the crew “likely caught the faintest ever seen with the unaided eye.” Apollo astronauts reported similar flashes from lunar orbit, so the claim concerns how dim these were, not that humans had never seen one.
Five flashes logged on tablets in the eclipse
The observations happened during a planned loss of communications while the spacecraft passed behind the Moon on the crew’s April 1 to April 10 round trip. According to NASA’s preliminary report, NASA astronaut Reid Wiseman logged the most flashes, with NASA astronaut Victor “Ike” Glover and Canadian Space Agency astronaut Jeremy Hansen each recording some. Hansen and Wiseman described one burst as “bloop”-like, and the crew’s reaction was a shouted “Dude! No way!”
NASA’s annotated image shows how the sightings were recorded. Wiseman, Glover and Hansen marked flashes in blue, green and red ink respectively in OneNote on a simulated view of the eclipsed Moon. Wiseman noted that three of the five flashes, numbers 1, 2 and 4, came roughly ten minutes into the eclipse, and flash 4 was seen by all three astronauts. The Lunar Science Team received the news in Mission Control at Johnson Space Center in Houston. The full Artemis II lunar science dataset has since been released to the global science community and the public, so the flash logs can be checked by outside groups.
Ruling out cosmic rays and spacecraft glints
A human watching through a window for faint flashes invites obvious doubts about what the eye is really picking up, and the science team addressed two of them directly. The eclipse itself helped: with the Sun hidden for 54 minutes, the Moon’s night side was dark enough that a pinprick of light could register against it, and the crew could also see planets, galaxies, stars and zodiacal light, the glow of sunlight scattered by interplanetary dust. According to the report, the team ruled out cosmic rays and reflections from the spacecraft before confirming the sightings. Cosmic rays can streak across an eye’s retina or a camera sensor as false flashes, and sunlit hardware can throw glints into a window.
The report estimates that each incoming rock was no more than a couple of inches wide and moving at thousands of miles per hour. NASA’s report does not give a brightness magnitude for the five Artemis II events, so the “faintest” ranking rests on the agency’s assessment and the word “likely” rather than a published photometric comparison.
Marshall’s telescope program as the yardstick
The nearest comparison is NASA’s own telescope program at Marshall Space Flight Center in Huntsville, Alabama. The Meteoroid Environment Office watches the Moon’s dark portion for about ten nights a month using two telescopes at its Automated Lunar and Meteor Observatory. Its program description says low-light cameras record 30 frames per second, and requiring both cameras to see an event filters out cosmic rays, because one cosmic ray can strike only one camera.
That program targets meteoroids larger than tens of grams, up to kilograms, with impact speeds from about 20 to over 72 kilometers per second. A 2014 paper by NASA Marshall’s Robert Suggs and colleagues, accepted by the journal Icarus, analyzed 126 flashes from the program’s more than 300 recorded since 2006. Those flashes came from impactors of roughly 0.4 grams to 3.5 kilograms, depending on the assumed luminous efficiency, with peak magnitudes between about 5.1 and 10.4.
NASA’s report says the observations help estimate how often small impacts occur, which bears on the long-term risk to future lunar habitats and infrastructure.
The same report carries the rest of the crew’s lunar science, including a pulsing solar-corona streamer photographed during the eclipse, the 80-mile-wide crater Carnot in low-angle light at the terminator, and Orientale Basin photographs matched to Lunar Reconnaissance Orbiter data. Surface colors were read as clues to composition, with blues suggesting titanium-rich volcanic rock, browns marking varying iron levels and greens pointing to volcanic glass or glass from impacts. A full-disk nighttime image of Earth showed auroras at both poles, a Saharan dust plume, lightning over the Congo basin and city lights. The impact count stands at five, from one eclipse, observed by three people over 54 minutes. The Marshall comparison also shows the gap in what is known: the program’s own description calls observations of meteoroids in this mass range “embarrassingly few,” so even a handful of crew-logged events adds to a thin record.
This article was produced with the assistance of AI and reviewed by Morning Overview editors prior to publication.
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