This year marks the 50th anniversary of humans landing on the Moon. Now NASA is headed to the Moon once again, using it as a proving ground for a future human mission to Mars. Use this opportunity to get students excited about Earth’s natural satellite, the amazing feats accomplished 50 years ago and plans for future exploration.
When NASA was founded in 1958, scientists were unsure whether the human body could even survive orbiting Earth. Space is a demanding environment. Depending on where in space you are, it can lack adequate air for breathing, be very cold or hot, and have dangerous levels of radiation. Additionally, the physics of space travel make everything inside a space capsule feel weightless even while it’s hurtling through space. Floating around inside a protective spacecraft may sound fun, and it is, but it also can have detrimental effects on the human body. Plus, it can be dangerous with the hostile environment of space lurking on the other side of a thin metal shell.
In 1959, NASA’s Jet Propulsion Laboratory began the Ranger project, a mission designed to impact the Moon – in other words, make a planned crash landing. During its descent, the spacecraft would take pictures that could be sent back to Earth and studied in detail. These days, aiming to merely impact a large solar system body sounds rudimentary. But back then, engineering capabilities and course-of-travel, or trajectory, mathematics were being developed for the first time. A successful impact would be a major scientific and mathematical accomplishment. In fact, it took until July 1964 to achieve the monumental task, with Ranger 7 becoming the first U.S. spacecraft to impact the near side of the Moon, capturing and returning images during its descent.
After the successful Ranger 7 mission, two more Ranger missions were sent to the Moon. Then, it was time to land softly. For this task, JPL partnered with Hughes Aircraft Corporation to design and operate the Surveyor missions between 1966 and 1968. Each of the seven Surveyor landers were equipped with a television camera – with later landers carried scientific instruments, too – aimed at obtaining up-close lunar surface data to assess the Moon’s suitability for a human landing. The Surveyors also demonstrated in-flight maneuvers and in-flight and surface-communications capabilities.
In 1958, at the same time JPL was developing the technological capabilities to get to the Moon, NASA began the Mercury program to see if it was possible for humans to function in space. The success of the single-passenger Mercury missions, with six successful flights that placed two astronauts into suborbital flight and four astronauts into Earth orbit, kicked off the era of U.S. human spaceflight.
In 1963, NASA’s Gemini program proved that a larger capsule containing two humans could orbit Earth, allowing astronauts to work together to accomplish science in orbit for long-duration missions (up to two weeks in space) and laying the groundwork for a human mission to the Moon. With the Gemini program, scientists and engineers learned how spacecraft could rendezvous and dock while in orbit around Earth. They were also able to perfect re-entry and landing methods and began to better understand the effects of longer space flights on astronauts. After the successful Gemini missions, it was time to send humans to the Moon.
The Apollo program officially began in 1963 after President John F. Kennedy directed NASA in September of 1962 to place humans on the Moon by the end of the decade. This was a formidable task as no hardware existed at the time that would accomplish the feat. NASA needed to build a giant rocket, a crew capsule and a lunar lander. And each component needed to function flawlessly.
Rapid progress was made, involving numerous NASA and contractor facilities and hundreds of thousands of workers. A crew capsule was designed, built and tested for spaceflight and landing in water by the NASA contractor North American Aviation, which eventually became part of Boeing. A lunar lander was developed by the Grumman Corporation. Though much of the astronaut training took place at or near the Manned Spacecraft Center, now known as NASA’s Johnson Space Center, in Texas, astronauts practiced lunar landings here on Earth using simulators at NASA’s Dryden (now Armstrong) Flight Research Center in California and at NASA’s Langley Research Center in Virginia. The enormous Saturn V rocket was a marvel of complexity. Its first stage was developed by NASA’s Marshall Space Flight Center in Alabama. The upper-stage development was managed by the Lewis Flight Propulsion Center, now known as NASA’s Glenn Research Center, in Ohio in partnership with North American Aviation and Douglas Aircraft Corporation, while Boeing integrated the whole vehicle. The engines were tested at what is now NASA’s Stennis Space Center in Mississippi, and the rocket was transported in pieces by water for assembly at Cape Kennedy, now NASA’s Kennedy Space Center, in Florida. As the Saturn V was being developed and tested, NASA also developed a smaller, interim vehicle known as the Saturn I and started using it to test Apollo hardware. A Saturn I first flew the Apollo command module design in 1964.
Unfortunately, one crewed test of the Apollo command module turned tragic in February 1967, when a fire erupted in the capsule and killed all three astronauts who had been designated as the prime crew for what became known as Apollo 1. The command module design was altered in response, delaying the first crewed Apollo launch by 21 months. In the meantime, NASA flew several uncrewed Apollo missions to test the Saturn V. The first crewed Apollo launch became Apollo 7, flown on a Saturn IB, and proved that the redesigned command module would support its crew while remaining in Earth orbit. Next, Earth-Moon trajectories were calculated for this large capsule, and the Saturn V powered Apollo 8 set off for the Moon, proving that the calculations were accurate, orbiting the Moon was feasible and a safe return to Earth was possible. Apollo 8 also provided the first TV broadcast from lunar orbit. The next few Apollo missions further proved the technology and allowed humans to practice procedures that would be needed for an eventual Moon landing.
On July 16, 1969, a Saturn V rocket launched three astronauts to the Moon on Apollo 11 from Cape Kennedy. The Apollo 11 spacecraft had three parts: a command module, called “Columbia,” with a cabin for the three astronauts; a service module that provided propulsion, electricity, oxygen and water; and a lunar module, “Eagle,” that provided descent to the lunar surface and ascent back to the command and service modules.
On July 20, while astronaut and command module pilot Michael Collins orbited the Moon, Neil Armstrong and Buzz Aldrin landed Eagle on the Moon and set foot on the surface, accomplishing a first for humankind. They collected regolith (surface “dirt”) and rock samples, set up experiments, planted an American flag and left behind medallions honoring the Apollo 1 crew and a plaque that read, “We came in peace for all mankind.”
After 21.5 hours on the lunar surface, Armstrong and Aldrin rejoined Collins in the Columbia command module and, on July 21, headed back to Earth. On July 24, after jettisoning the service module, Columbia entered Earth’s atmosphere. With its heat shield facing forward to protect the astronauts from the extreme friction heating outside the capsule, the craft slowed and a series of parachutes deployed. The module splashed down in the South Pacific Ocean, 380 kilometers (210 nautical miles) south of Johnston Atoll. Because scientists were uncertain about contamination from the Moon, the astronauts donned biological-isolation garments delivered by divers from the recovery ship, the aircraft carrier the USS Hornet. The astronauts boarded a life raft and then the USS Hornet, where the outside of their biological-isolation suits were washed down with disinfectant. To be sure no contamination was brought back to Earth from the Moon, the astronauts were quarantined until Aug. 10, at which point scientists determined the risk was low that biological contaminants or microbes had returned with the astronauts. Columbia was also disinfected and is now part of the National Air and Space Museum in Washington, D.C.
The Apollo program continued with six more missions to the Moon over the next three years. Astronauts placed seismometers to measure “moonquakes” and other science instruments on the lunar surface, performed science experiments, drove a carlike moon buggy on the surface, planted additional flags and returned more lunar samples to Earth for study.
Why It’s Important
Apollo started out as a demonstration of America’s technological, economic and political prowess, which it accomplished with the first Moon landing. But the Apollo missions accomplished even more in the realm of science and engineering.
Some of the earliest beneficiaries of Apollo research were Earth scientists. The Apollo 7 and 9 missions, which stayed in Earth orbit, took photographs of Earth in different wavelengths of light, highlighting things that might not be seen on the ground, like diseased trees and crops. This research led directly to the joint NASA-U.S. Geological Survey Landsat program, which has been studying Earth’s resources from space for more than 45 years.
Samples returned from the Moon continue to be studied by scientists around the world. As new tools and techniques are developed, scientists can learn even more about our Moon, discovering clues to our planet’s origins and the formation of the solar system. Additionally, educators can be certified to borrow lunar samples for use in their classrooms.
Perhaps the most important scientific finding came from comparing similarities in the composition of lunar and terrestrial rocks and then noting differences in the amount of specific substances. This suggested a new theory of the Moon’s formation: that it accreted from debris ejected from Earth by a collision with a Mars-size object early in our planet’s 4.5-billion-year history.
The 12 astronauts who walked on the Moon are the best-known faces of the Apollo program, but in numbers, they were also the smallest part of the program. About 400,000 men and women worked on Apollo, building the vehicles, calculating trajectories, even making and packing food for the crews. Many of them worked on solving a deceptively simple question: “How do we guide astronauts to the Moon and back safely?” Some built the spacecraft to carry humans to the Moon, enable surface operations and safely return astronauts to Earth. Others built the rockets that would launch these advanced spacecraft. In doing all this, NASA engineers and scientists helped lead the computing revolution from transistors to integrated circuits, the forebears to the microchip. An integrated circuit – a miniaturized electronic circuit that is used in nearly all electronic equipment today – is lighter weight, smaller and able to function on less power than the older transistors and capacitors. To suit the needs of the space capsule, NASA developed integrated circuits for use in the capsule’s onboard computers. Additionally, computing advancements provided NASA with software that worked exactly as it was supposed to every time. That software lead to the development of the systems used today in retail credit-card swipe devices.
Some lesser-known benefits of the Apollo program include the technologies that commercial industries would then further advance to benefit humans right here on Earth. These “spinoffs” include technology that improved kidney dialysis, modernized athletic shoes, improved home insulation, advanced commercial and residential water filtration, and developed the freeze-drying technique for preserving foods.
Apollo was succeeded by missions that have continued to build a human presence in space and advance technologies on Earth. Hardware developed for Apollo was used to build America’s first Earth-orbiting space station, Skylab. After Skylab, during the Apollo-Soyuz test project, American and Soviet spacecraft docked together, laying the groundwork for international cooperation in human spaceflight. American astronauts and Soviet cosmonauts worked together aboard the Soviet space station Mir, performing science experiments and learning about long-term space travel’s effects on the human body. Eventually, the U.S. and Russia, along with 13 other nations, partnered to build and operate the International Space Station, a world-class science laboratory orbiting 400 kilometers (250 miles) above Earth, making a complete orbit every 90 minutes.
And the innovations continue today. NASA is planning the Artemis mission to put humans on the Moon again in 2024 with innovative new technologies and the intent of establishing a permanent human presence. Working in tandem with commercial and international partners, NASA will develop the Space Launch System launch vehicle, Orion crew capsule, a new lunar lander and other operations hardware. The lunar Gateway – a small spaceship that will orbit the Moon and include living quarters for astronauts, a lab for science, and research and ports for visiting spacecraft – will provide access to more of the lunar surface than ever before. While at the Moon, astronauts will research ways to use lunar resources for survival and further technological development. The lessons and discoveries from Artemis will eventually pave a path for a future human mission to Mars.
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