What if they have their eyes closed?
#1 They won’t necessarily know when it’s coming
#2 6 million candlepower can be seen through your eyelids.
“In candlepower the sun intrinsic brightness, as seen at sea-level, is equal to the light of 270,000 to 300,000 candles for each square inch of its surface.” http://www.kgbanswers.com/how-bright-is-the-sun-in-candlepower/20327605
Lol, I know somewhere there is a Three Stooges short...yuk, yuk, yuk....