Who ferries souls across the River Styx in the underworld?

Charon

Who prayed fervently for rain after years of drought, resulting in a cloud appearing over the sea? Who portrayed astronaut Mark Watney in "The Martian"? Who was king when the Union of the Crowns unified Scotland and England in 1603? Which 1857 Supreme Court decision ruled African Americans were not U.S. citizens? Who developed the zeta function critical to number theory?