In July 1969, Michael Collins orbited alone on the far side of the Moon while Armstrong and Aldrin walked below, and for 48 minutes of every 2-hour loop he was cut off from radio contact — the most physically isolated human in history, and by his own account not lonely but quietly content in the dark.

For 48 minutes of every 2-hour orbit, Michael Collins flew alone behind the Moon, cut off from Earth and his crewmates by 2,000 miles of rock — the most physically isolated human being in history, and by his own account not lonely but quietly content. The pos…