Not sure how it happens, but my grandmother told me about it when I was growing up. Just to be sure, I asked my mom who confirmed that she, too, was told the same growing up. I remember seeing it myself when I was 7 years old, however, I know how kid's minds are, so I'm not sure if I just imagined it. It wasn't like bright daylight. It was like what you'd see at around 6:00 a.m. on the eastern seaboard, but it happens twice like that...once in the middle of the night and again at regular time.