Earlier today, in recommending Randall Munroe's "What If?" book, I mentioned that there was only one question I was able to figure out: "What is the farthest one human being has ever been from every other living person?" Munroe's answer:
The most likely suspects are the six Apollo command module pilots who stayed in lunar orbit during a Moon landing: Mike Collins, Dick Gordon, Stu Roosa, Al Worden, Ken Mattingly, and Ron Evans. Each of these astronauts stayed alone in the command module while two other astronauts landed on the Moon. At the highest point in their orbit, they were about 3,585 kilometers [2,228 miles] from their fellow astronauts.
And about 230,000 miles from the rest of us on Earth.