Apollo’s moon mission was one of the most expansive government initiatives in American history. During its peak years, some 34,000 NASA employees and 375,000 outside contractors took part in the program. Budget estimates vary, but in 2008, the Congressional Research Service put Apollo’s inflation-adjusted costs at $98 billion—several times more expensive than the Manhattan Project and the equivalent of almost $500 for every man, woman and child living in the United States in 1969.

Apollo unfolded during the famous “space race” between the United States and the Soviet Union, but in September 1963, President John F. Kennedy shocked the world by suggesting that the two Cold War foes might join forces for a tandem lunar mission. “In a field where the United States and the Soviet Union have a special capacity—in the field of space—there is room for new cooperation, for further joint efforts in the regulation and exploration of space,” he said in a United Nations speech. “I include among these possibilities a joint expedition to the moon.”

The president’s proposal was most likely driven by the soaring costs of the Apollo program and a desire to ease tensions with the Russians. While there is evidence that the Soviets considered the idea, it was abandoned following Kennedy’s November 1963 assassination.

On January 27, 1967, astronauts Gus Grissom, Ed White and Roger Chaffee climbed inside their Apollo 1 spacecraft for a routine prelaunch test. As they sat on the launch pad, a spark from some faulty wiring triggered a massive fire that tore through the cabin’s pure oxygen atmosphere. A complicated latch system on the hatch made it all but impossible for the astronauts to escape, and by the time ground crews finally opened it several minutes later, all three men had died from asphyxiation. The fire marked the first time that American astronauts were killed inside a spacecraft. It grounded Apollo for 18 months, but it also led NASA to make crucial design improvements that increased safety and performance during the lunar missions.

Apollo’s first manned mission began in October 1968, when Apollo 7 entered low-Earth orbit to conduct a shakedown of the command and service module. During the 11-day flight, astronauts Wally Schirra, Donn Eisele and Walter Cunningham made the first live television transmissions from inside a manned spacecraft. Billed as coming “from the lovely Apollo room, high atop everything,” the broadcasts treated viewers to tours of the spacecraft, demonstrations of how meals were prepared in zero gravity, and plenty of wisecracks from the crew. The “Wally, Walt and Donn Show” proved to be a massive hit. After returning home, the astronauts were even given a special Emmy Award by the National Academy of Television Arts and Sciences.

NASA’s Director of Flight Crew Operations Deke Slayton adhered to an impartial rotation system for the Apollo missions. Each three-man team of astronauts served as the backup crew on a flight, and then became prime crew of their own mission three flights later. For the first moon landing, however, Slayton considered handpicking a commander. Gus Grissom was the leading candidate before his death in the Apollo 1 fire, and Slayton later informally offered the job to Apollo 8 commander Frank Borman, who turned it down in favor of retiring. In the end, the historic Apollo 11 mission fell to Neil Armstrong, Buzz Aldrin and Michael Collins—the next crew in the rotation line. “I wasn’t chosen to be first,” Armstrong later said. “I was just chosen to command that flight, which turned out to be the first landing. Circumstances put me in that particular role.”

When Neil Armstrong took his “one small step for man, one giant leap for mankind” in July 1969, he was wearing a spacesuit crafted by Playtex, a company better known for making ladies’ bras and girdles. The International Latex Corporation—the industrial division of Playtex—won a contract to build Apollo spacesuits in 1962, and later sealed the deal after besting two other companies in a design competition. It went on to create the A7L and A7LB, a pair of hand-sewn spacesuits that protected the Apollo astronauts from the elements while also giving them the freedom of movement required to collect moon rocks, conduct scientific experiments and drive the lunar rover. Playtex’s spacesuit division split off from the main company in 1967, and it continues to serve as a NASA contractor under the name ILC Dover.

Apollo’s second lunar landing mission took off on November 14, 1969, during a brief lull in a thunderstorm. All went according to plan at first, but just 36 seconds after liftoff, the spacecraft and its roaring Saturn V rocket suffered a lightning strike. Moments later, a second bolt of lightning tore through the ship and wiped out many of its electrical systems. Inside the cockpit, Apollo 12 astronauts Pete Conrad, Alan Bean and Richard Gordon heard the master alarm and saw their instrument panel glow with warning lights. NASA considered aborting the mission, but a young flight controller remembered a method for switching the spacecraft’s Signal Conditioning Equipment to an auxiliary setting, which allowed the crew to reconnect the ship’s fuel cells and bring its navigation platform back online once in orbit. Despite beginning its mission with a near-disaster, Apollo 12 went on to make a successful moon landing.

During his voyage to the moon and back with Apollo 14, astronaut Edgar Mitchell secretly carried out the space program’s only experiment in extrasensory perception, or ESP. Mitchell had a deep interest in psychological phenomena, and before leaving for the moon, he concocted a test to see if it was possible to transmit his thoughts through space. While his fellow crew members Alan Shepard and Stuart Roosa slept, Mitchell took out a collection of cards and spent a few minutes concentrating on a random series of symbols. Back on Earth, a team of psychics tried to read his thoughts and write down the order of the sequence. The group reportedly guessed the right numbers 51 times out of 200, which Mitchell described as “results far exceeding anything expected.” A few years after returning from his moon mission, Mitchell continued his psychic research by founding the Institute of Noetic Sciences, a nonprofit group devoted to studying human consciousness.

NASA knew very little about the moon before the Apollo missions—including whether it harbored hazardous microbes or “space germs.” With this in mind, the crews of Apollo 11, 12 and 14 were quarantined after they returned home from their lunar landings. The astronauts were required to slip into anti-contamination suits as soon as they were plucked out of the sea, and they were then sealed off for three weeks inside a converted Airstream trailer called the Mobile Quarantine Facility, or MQF. In the case of Apollo 12, the astronauts were even forced to spend Thanksgiving inside the MQF, so a special turkey dinner was prepared for them. Luckily for the crews of Apollo 15, 16 and 17, NASA later concluded there was no risk of moon diseases and scrapped its quarantine measures in 1971.

By the time Apollo 17 ended in 1972, six different lunar expeditions had left the moon’s surface littered with everything from discarded spacecraft parts to scientific experiments and even a photo of astronaut Charlie Duke’s family. Still, the most unusual relic might be “Fallen Astronaut,” an aluminum sculpture designed by Belgian artist Paul van Hoeydonck and secretly left on the moon in August 1971 by Apollo 15 commander David Scott. Scott believed that the minimalist artwork should serve as a memorial to those that had died in the pursuit of space exploration, so he placed it alongside a plaque inscribed with the names of 14 lost American astronauts and Soviet cosmonauts.