Why Astronauts See Flashes with Eyes Closed

Hinzugefügt: 2026-05-28

[00:00:00]When you've left Earth, there's no atmosphere to provide such protection for you. We would [music] learn among the Apollo astronauts, who were the first astronauts to leave Earth for a destination.

[00:00:14]They would see flashes of light. They would just see it with their eyes open and with their eyes closed. Evidence that something's getting triggered on their retina, just like what was happening in my CCD photos at the telescope on mountaintops. So, it's evidence that something's happening internal to the eye.

[00:00:33]But, you still want to know what's causing it.

[00:00:36]So, they decided, "Let's create a helmet for you that has detectors on it for cosmic rays. And if a cosmic ray triggers your helmet at the same time you see a flash, there's hard evidence that you're seeing the interaction of cosmic rays with your retina and not some mysterious cosmic alien force trying to get inside your head." Sure enough, that's exactly what was observed.