Houston ? Johnson Space Center staff and retirees Tuesday marked the 35th anniversary of the first manned lunar landing with MoonPies, a vintage car parade and proud reflections of a deed that dazzled the world.

The celebration was a far cry from the 1969 bash that some remembered as a “drunken orgy” to mark the safe return of the Apollo 11 crew of Neil Armstrong, Buzz Aldrin and Michael Collins.

“The cigars came out,” retiree Norman Chaffee, 67, said Tuesday. “The flags came out. Boy, you put away your slide rule. For about 24 hours, there were people stumbling out there on the road. That was just a tremendous party.”

It was also a time of less technology — and less bureaucracy, veterans recalled.

“I stared up at the moon and couldn’t believe what we had just done,” JSC’s chief engineer, Jay Greene, said as celebrants browsed mock-ups of the moon’s surface, a personal hygiene kit that traveled with the astronauts, newspaper articles from 1969 and pictures of the crew that flew the famed mission.

“We went to the moon with slide rules,” noted Chaffee, who worked on the spacecraft propulsion system. “I didn’t even have my first full-function calculator until 1972. There was much less bureaucratic oversight at that time. People generally felt like if it made sense, go ahead and do it.

“We were much less risk-averse. Now with the Challenger accident and the Columbia accident and some of the other things, we have become so risk-averse that we don’t dare do things,” he said, adding: “The key is to take responsible risks.”

Randy Stone, deputy director of the Johnson Space Center, said many things made the Apollo era easier than today for space projects. “We were in the Cold War,” he said. “We were in a technological race that most people believed we could not afford to lose.

“The naysayers didn’t have as much influence,” Stone said. “It was still hard to get money, but it wasn’t near as hard as it is today.”

Apollo 11 astronaut Buzz Aldrin speaks to reporters in front of the Saturn 5 Aft End, the F-1 rocket engines of the first stage of the Apollo 11/Saturn 5 launch vehicle, in Washington. The 35th anniversary of the first moon landing was celebrated Tuesday. Aldrin and astronauts Neil Armstrong and Michael Collins were the crew of Apollo 11.

Stone said accomplishing something great, however, is difficult regardless of the era: “Technical things and things where you are putting people’s lives at risk are tough at any time.”

The challenges of the Apollo 11 mission were so all-consuming that Cecil Gibson, who also worked on the rocket’s propulsion system, said he didn’t even know his first child had been born until three days later.

“By the time it kind of settled down and I got a chance to go home, I had a 3-day-old daughter,” Gibson recalled Tuesday. “We called her the moon baby.”

Milt Heflin, chief of JSC’s Flight Director Office, said taking a man to the moon was the “gutsiest thing that we have ever, ever done.

“At that time, you could feel it. Man, we were on a roll,” he said.