I was reading about Neil Armstrong recently and I got to wondering why they used him instead of one of the surviving Mercury 7 as the first man on the moon. Were they getting too old for the program?
Several of the previous Mercury Astronauts died when the capsule caught fire on the launch pad. They never had the opportunity to fly moon missions.
Glenn - retired before Gemini got rolling, wanted to get into politics.
Carpenter - Performed poorly on his Mercury flight, retired, got into the Sealab (the real Sealab) program.
Grissom - Killed on the launch pad in 1967. Almost certainly would have been on a lunar landing mission.
Shepard - Apollo 14, only because he had experimental surgery to fix an inner ear problem that had grounded him since his Mercury flight.
Schirra - Apollo 7, crew performed poorly on their flight and were not assigned to other Apollo missions.
Cooper - Was up for a Apollo moon mission, but had a fallout with management and retired.
Slayton - Heart murmur grounded him until the Apollo-Soyuz mission.
One of the Mercury astronauts, Shepard, wound up going to the moon. And, as aceplace57 mentioned, Grissom died in Apollo 1.
When the Apollo and Gemini programs began to ramp up, NASA slightly changed what they were looking for in an astronaut. The Mercury astronauts were primarily picked because of their experience as pilots. However, when selecting the next group of astronauts, NASA placed more emphasis on candidates who had a strong engineering background – presumably because someone like that would be in a better position to respond to handle the technical challenges of running a complicated piece of machinery when there was no opportunity of help from earth.
Armstrong was picked to command Apollo 11 because he’d done a great job in prior flights with Gemini and Apollo. The first landing was too important to give to someone just for sentimental reasons.
Just looking at Grissom’s Wikipedia entry, it includes this quote from Deke Slayton “Had Gus been alive, as a Mercury astronaut he would have taken the step [first step on the Moon] … My first choice would have been Gus, which both Chris Kraft and Bob Gilruth seconded.”
The quote is cited, so I presume it’s true. 
What constituted poor performance?
Having read Glenn’s autobiography, ISTR that there’s more to it than that. If memory serves, he wanted to continue as an astronaut, but, as the US’s first man to orbit the Earth, he had a position of peculiar prominence (and was seen as a hero by many). As such, he found himself under pressure to leave the astronaut program – NASA and the government didn’t want to suffer the embarrassment of losing the space program’s biggest hero in an accident.
He always longed to get back to space, which was why, when NASA offered to send him up on the Shuttle in '98, he jumped at the chance.
Wha? I had not heard this. I was always under the impression that Wally Schirra was the true engineer. Apollo 7 was a low Earth orbit test of the CM.
How did the crew perform poorly?
Wikipedia has plenty of details, including transcripts.
Schirra feuded with mission control during the flight, clearly irritable with their instructions. He and his crew mates complained about the food and about tasks they were asked to do. They were slated to do the first live TV broadcast from space, which Schirra didn’t want to do.
Schirra decided they should go through re-entry and landing with their helmets off, over strenuous objections from the folks on the ground.
As far as I know, Carpenter nearly ran out his fuel on Aurora 7 from over-corrections. He almost didn’t have enough for re-entry. Schirra’s next mission, Sigma 7 went up with the same amount of fuel, did more maneuvers, and returned with over half his reserves. After that, Scott Carpenter’s name was Mudd at NASA.
IIRC, the Apollo Seven crew also had head colds during the flight. My understanding was that in zero G, your sinuses don’t drain fluid so much as squeeze their way out. They were miserable (from what I remember reading from 45 years ago).
the Mercury astronauts were all test pilots in the military used to being in control of the aircraft and left to their own devices, this worked well for the needs of Project Mercury.
When Project Gemini started these guys would argue who got to be the pilot. They knew the Apollo program was coming and they were fighting over who would be the pilot and who would ride shotgun. this didn’t work out well.
Wally Schirra was the best behaved.
Carpenter nearly ran out of fuel to maneuver and overshot his landing by about 200 miles. In his defense, the new maneuvering system for his mission was not at all refined, and it consumed fuel at a high rate. That said, he was preoccupied with experiments which NASA opposed for technical reasons. When he re-entered the atmosphere they initially thought he had burned up or skipped off and that it was a terrible disaster. Chris Kraft was livid and said that Carpenter would never go up again.
Schirra, as stated earlier, argued with Ground Control. Again, there was a reason: he had a head cold and was very uncomfortable. However, the guys on the ground were, and remain, the final word, and by defying them publicly (anybody could listen on the radio) he wrecked his chances of going back up again.
When the whole thing started NASA was adamantly against having pilots, they thought that the people that went up would be test subjects and that pilots were big egomaniacs. Eisenhower insisted on pilots, and the Mercury Seven proved the engineers absolutely correct in their assessment. Gordon Cooper vindicated them, though, when he saved his mission after an almost total failure. He brought it down himself, something the engineers initially thought would be totally unnecessary.
Ultimately, the Mercury Seven were a product of their times. The men that came later had more varied backgrounds and had more than the ability to survive harsh conditions. The Mercury Seven weren’t even particularly notable pilots except for Glenn, none had done anything really special. Once it was established that being in space wasn’t a physical hardship the program opened up to people with other skills and more dramatic accomplishments that far overshadowed those of the Mercury Seven astronauts. NASA was glad for it, too, because while the first seven were a public relations boon they really were a pain in NASA’s ass. The ones who came later weren’t nearly as public, and as such didn’t make demands or give orders, they followed them.
Glenn’s Wikipedia page mentions the “Glenn was too important a figure to fly again” story but seems to suggest that it is only conjecture. Haven’t read his autobio though.
Yuri Gagarin was grounded officially, but only after the Soyuz 1 accident, which Gagarin was the backup pilot for. He strenuously objected to its launch fearing the capsule was not ready for flight, and was proven correct.
I wish to question this assertion.
I read a book co-written by Eugene Cernan The Last Man on the Moon last year.
He reports that on his Gemini 9A flight link, he went EVA and had a very tough time dealing with his suit. (It ballooned up in vacuum and became much more difficult to bend at the knees and elbows.) His job (among other things) was to see if a spacewalking astronaut could use his flexible [life support] umbilical as an orientation/manuevering aide. He worked on it for 30 - 45 minutes. His temp skyrocketed, his heart rate was high, and he reported that trying to do things in the suit was like lifting weights the entire time. (He also said the umbilical was like wrestling with a pissed off charged fire hose.) He was as fit as he could be, but utterly exhausted after his spacewalk. (He also had trouble getting back into the capsule due to the inflexibility of his suit.)
Some of this (like the suit flexibility and cooling issues) was corrected for Apollo, but it sure wasn’t established that space wasn’t a physical hardship… they were learning news things (and procedures to compensate) all the time. 
The tests they ran at the Lovelace clinic to determine the first astronauts had nothing to do with adaptability, procedures, or the like. They were tests meant to determine their physical endurance, pain threshold, psychological strength, etc. Once it was determined that none of these things, however desirable they might be, were necessary, it opened things up for guys like Pete Conrad, rejected in the first round with a note that he was not suitable for long-duration flight.
They had no idea what it would take, so they took the 7 most steely-eyed people they could find. That was their gift, more than anything else, a willingness to put up with incredible abuse and a tolerance that others lacked. That’s what I mean by “physical hardship”. Naturally, being cooped up in a tiny capsule for an extended period of time is a hardship, but that was well-known by the time they got to Gemini and Apollo.
We’ll probably end up agreeing, but I need more caffeine, because I don’t see what you mean by stating that “Once it was established that being in space wasn’t a physical hardship”, but then in this next post saying that there was indeed a hardship.
Do you mean that they finally quantified the level of hardship (after sending guys up to see), as opposed to just taking a WAG?
IMO, what they wanted was guys who could think and act under pressure (and, of course, choosing the correct action to take). They didn’t send up Lou Ferrigno’s, after all, so physical strength was “nice to have”. In their guess, military background helps with the training they get for working under stress.
Part of the reason they went to getting more scientists on the flights (and I think Cernan may have touched on this in his book) was that the earthbound scientists didn’t trust the “jocks” to do the space experiments correctly. Sometimes, when unexpected results/readings came back, the ground based scientists suspected the jocks of fouling up the experiments somehow. 
EDIT: I apologise for my opinions and speculations in GQ.
Nitpick: That’s mud, the phrase has nothing at all to do with Dr Samuel Mudd and predates him. Earliest cite in OED is 1823, 10 years before the birth of Dr Mudd.
Small point I know but this is the Dope.
[continuing hijack]You know, I thought it was ‘mud’, but then decided I was wrong. Thanks for the correction.
IIRC, Right Stuff that he was portrayed as remaining the coolest under stress of of all the Mercury Seven. There was a passage in a book where Cooper is flying a single engine plane in the Everglades, and someone who is riding shotgun is feeling sick from terror because he can hear the whomp, whomp of the prop hitting the marsh grass as Cooper skimming along the surface. Made me blanch when I read it. :eek: