Judy Woodruff:

Fifty years ago this week, the world watched as the Apollo 11 crew lifted off, and then landed on the moon a few days later.

Much of the attention, and especially during milestone anniversaries, has focused on Neil Armstrong and Buzz Aldrin, the astronauts who first set foot on the moon, but the work and efforts of their command module pilot and crew member, Michael Collins, was crucial, too.

As Miles O'Brien tells us, Collins had a perspective and concerns of his own that were distinct to the mission.

His profile is the focus of tonight's Leading Edge segment.