" " Nothing is bigger than Elvis, not even a possible signal from space aliens. Big Ear Radio Observatory/Fotos International/Getty Images

A former Ohio State University electrical engineering and astronomy professor named Jerry Ehman, who was working as a volunteer at the university, glanced at computer printouts from the "Big Ear." The latter was a radio telescope that was scanning the cosmos in hopes of picking up communications from an extraterrestrial civilization. Up to that point, it hadn't found anything at all.

But to Ehman's shock, on Aug. 15, 1977, he saw an unusually strong signal. Instead of the typical random numbers, there was a stream of both letters and numbers telegraphing a radio transmission 30 times louder than the background buzz of deep space. Ehman was so amazed he circled the code and wrote the word "wow!" next to the printout.

Scientists searched in vain for the signal, but couldn't pick it up again. Even today, the "wow" code remains unexplained [sources: Kawa, Kiger].

You'd think that a discovery like that would have made the headlines, or at least graced the covers of supermarket tabloids. Unfortunately for space buffs, it occurred the day before the death of music legend Elvis Presley [source: Adams]. No one can compete with Elvis.