time. Astronauts who went on other missions reported mainly "elongated shapes". About 40% of those surveyed reported a "stripe" or "stripes" and about 20% reported a "comet" or "comets". 17% of the reports mentioned a "single dot" and only a handful mentioned "several dots", "blobs" and a "supernova". Motion A reporting of motion of the LF was common among astronauts who experienced the flashes. For example, Jerry Linenger reported that during a solar storm, they were directional and that they interfered with sleep since closing his eyes would not help. Linenger tried shielding himself behind the station's lead-filled batteries, but this was only partly effective. The different types of directions that the LF have been reported to move in vary across reports. Some reported that the LF travel across the visual field, moving from the periphery of the visual field to where the person is fixating, while a couple of others reported motion in the opposite direction. Terms that have been used to describe the directions are "sideways", "diagonal", "in-out" and "random". In Fuglesang et al. (2006), it was pointed out that there were no reports of vertical motion. Occurrences and frequencies There appear to be individual differences across astronauts in terms of whether they reported seeing the LF or not. While these LF were reported by many astronauts, not all astronauts have experienced them on their space missions, even if they have gone on multiple missions. For those who did report seeing these LF, how often they saw them varied across reports. On the Apollo 15 mission all three astronauts recorded the same LF, which James Irwin described as "a brilliant streak across the retina". Frequency during missions On Lunar missions, once their eyes became adapted to the dark, Apollo astronauts reported seeing this phenomenon once every 2.9 minutes on average. On other space missions, astronauts reported perceiving the LF once every 6.8 minutes on average. The LF were reported to be seen primarily before the astronauts slept and in some cases disrupted sleep, as in the case of Linenger. Some astronauts pointed out that the LF were seemingly perceived more frequently as long as they were perceived at least once before and attention was directed to the perception of them. One astronaut, on his first flight, only took note of the LF after being told to look out for them. These reports are not surprising considering that the