It has long been known that many people in space experience sudden phosphenes, or light flashes. Although it is clear that they are related to
high-energy particles in the space radiation environ- ment, many details about them are still unknown. In an effort to gain more knowledge about the
light flashes, a study was initiated to collect information from people who have recently flown in space. Method: A survey conducted by anonymous
questionnaire was performed among astronauts regarding their experience of sudden light flashes in space. In all, 98 surveys were distributed to
current NASA and ESA astronauts. Results: Among the 59 respondents, 47 noticed them sometime during spaceflight. Most often they were noted before
sleep, and several people even thought the light flashes disturbed their sleep. The light flashes predominantly appear white, have elongated shapes,
and most interest- ingly, often come with a sense of motion. The motion is described as sideways, diagonal, or in-out, but never in the vertical
direction. Dis- cussion: Comparisons with earlier studies of light flashes in space and several ground-based studies during the 1970s are made. One
interest- ing observation from this is that it seems that a small fraction of the light flashes is caused by Cherenkov radiation, while the majority
is probably caused by some kind of direct interaction with elements in the retina. |
). by reading the comparable ranges or sensitivities, it is most certain i got a
slightly better PMT; however 
