Apollo 8 was the first human spaceflight to leave Earth orbit; the first to be captured by and escape from the gravitational field of another celestial body; and the first crewed voyage to return to planet Earth from another celestial body-Earth's Moon. After launching on December 21, 1968, Apollo 8 took three days to travel to the Moon. It orbited ten times over the course of 20 hours, during which the crew made a Christmas Eve television broadcast in which they read the first 10 verses from the Book of Genesis. At the time, the broadcast was the most watched TV program ever. Apollo 8's successful mission paved the way for Apollo 11 to fulfill U.S. President John F. Kennedy's goal of landing a man on the Moon before the end of the decade.
It's a shame they canceled the Constellation Program. Would have been incredible to see man landing on Mars.