Famed Mercury astronaut John Glenn has an open seat at his lunch table, provided you're willing to foot the bill. Glenn, the first American to orbit the Earth, is offering an afternoon lunch as part of a charity auction for the Astronaut Scholarship Foundation, which is raising college scholarship funds for aspiring engineers and scientists. It was 50 years ago today that NASA unveiled Glenn and the six other Mercury astronauts - the country's first spaceflyers - to the world in a frenzied press conference that made the seven men instant national heroes. On that April 9 in 1959, Glenn...