‘A Kind of Immortality.’ Carl Sagan’s Widow Ann Druyan on Voyager 1’s 40th Anniversary

The greatest conceptual art pieces ever mounted have been on exhibit for nearly 40 years now. The admission is free and the art is first rate, but you're never going to get a chance to enjoy it — not unless you can figure out a way to travel nearly 13 billion miles from Earth.

That's how far away the Voyager 1 spacecraft, launched 40 years ago on Sept. 5, 1977, currently is, but it won't hold that position for long; it's speeding outward all the time at about 38,000 mph, according to NASA.