399 B.C.
Human History: In 399 B.C. the Greek philosopher Socrates was convicted of corrupting the youth of Athens and dishonoring the gods. Rather than compromise his ideals, he commited suicide by drinking the poison hemlock.
Alien History: All of Socrates friends were amazed that a 90 year old man could have such a "buffed out" physique. Most believed it was due to his use of free weights and sticking to the Slim-Fast Plan. Actually, his muscles were a result of steroids, which he got from Mother Vega, a Cthuthian time traveler. Mother Vega roamed through earth-time dispensing chicken soup, vitamin E, lox and bagles, nutritional supplements, and steroids. Unfortunately for Socrates, he asked her for one too many pills and ended up choking to death on his own vomit...which is an unpleasant death, but better than choking to death on someone else's vomit.