NASA announced the Apollo 11 crew today: Neil Armstrong commanding, Buzz Aldrin as lunar module pilot, and Mike Collins as command module pilot.

These are the men who will attempt the first lunar landing. If Apollo 10 goes well in May — and it needs to go well — Armstrong and Aldrin will be the first humans to walk on the Moon.

I’ve been watching Armstrong since Gemini 8, when he diagnosed and recovered from a spacecraft spin that could have killed him and his crewmate. He’s deliberate and precise and not given to public displays of ego. He came from the research pilot world at Edwards Air Force Base, where you test aircraft at the edge of what’s physically possible and you write up the results in careful technical language. He’s a scientist-pilot in the tradition the program has been developing. He’ll be the first man down the ladder, if everything goes right.

Aldrin I’ve been watching since Gemini 12, where he solved the spacewalk efficiency problem that had frustrated earlier astronauts. He has a doctorate from MIT in orbital mechanics. He understands the physics of what he’s doing at a level that gives him analytical reserves most pilots don’t have. He can improvise from first principles if the procedures don’t cover a situation.

Collins flew Gemini 10 and did an EVA to retrieve equipment from a target vehicle — a complex, successful mission. He’ll be the most isolated human being in history: orbiting the Moon alone in the command module for the hours the others are on the surface, out of radio contact on the far side on every orbit. He does not seem troubled by this in the accounts I’ve read of his interviews.

There are people asking why it’s Armstrong and not someone else. The short answer is that the crew assignment process rotates through the training groups, and Armstrong’s backup slot on Apollo 8 put him in line for Apollo 11 by the standard rotation. He also has the kind of unflappable professional record that makes him exactly the right person for a mission that will have problems we can’t anticipate.

If Grissom were alive, I think it would have been him. But Armstrong is the right choice for what this mission is.

May: Apollo 10. June or July: the attempt.

I’m going to try to enjoy the dress rehearsal.