ISS Astronauts Still See Light Flashes Every Few Minutes as Cosmic Rays Pierce 400-Km Orbit
Updated
Updated · spacedaily.com · Jul 6
ISS Astronauts Still See Light Flashes Every Few Minutes as Cosmic Rays Pierce 400-Km Orbit
3 articles · Updated · spacedaily.com · Jul 6
Summary
ISS astronauts continue to see brief light flashes with their eyes closed—typically once every few minutes—as galactic cosmic rays pass through the station and strike the retina.
ALTEA, an ISS experiment using helmet-mounted silicon detectors, found most reported flashes matched a heavy ion crossing an astronaut’s head; rates rise at higher latitudes and in the South Atlantic Anomaly.
Apollo crews first reported the phenomenon from Apollo 11 onward, describing points, streaks and comet-like shapes before NASA later turned the sightings into formal experiments.
The flashes themselves are harmless, but the particles behind them can leave microscopic tracks of damaged cells, a radiation risk that grows beyond Earth orbit and shapes shielding plans for future Moon and Mars missions.
Space radiation is shown to harm female biology more, so how can missions to Mars be made safe for every astronaut?
If studies show no increased cancer death in past astronauts, are the severe radiation risks for future Mars missions being overestimated?
With cosmic rays linked to declassified UAP files, what other historical space mysteries might this radiation phenomenon finally solve?
Astronauts’ Light Flashes Reveal Deep Space Radiation Risks: Insights from Artemis and ISS Missions
Overview
Astronauts traveling beyond Earth's protective magnetosphere have long reported seeing mysterious light flashes in their eyes, even with their eyes closed. These flashes are caused by high-energy cosmic rays from deep space interacting directly with the retina, highlighting the constant radiation exposure astronauts face. The Artemis program, especially Artemis I with its advanced radiation sensors, has provided new data on this invisible threat, showing that radiation levels in deep space are much higher than in low Earth orbit. These findings emphasize the ongoing challenge of protecting astronaut health during extended missions beyond Earth.