NASA:

NASA's Curiosity rover has beamed back its first color photo from the ancient crater where it landed on Mars and a video showing the last 2 1/2 minutes of its white-knuckle dive through the Martian atmosphere, a sneak peek of a spacecraft landing on another world.

If some fantastic machine were to send me back to the year 1012, I would find nothing in that world, which is by no means a distant world, to show that in just a 1000 years humans will be sky-craning robots on another planet.

Absolutely, utterly nothing. Knowing this to be as true as the airplane that's noisily flying over Beacon Hill at this very moment, I should shut up about what the future holds for space travel and other forms of transportation.