List of Apollo missions

The Apollo program was a United States human spaceflight program that took place from 1961 to 1972. It was led by the National Aeronautics and Space Administration (NASA) and aimed to send people to the Moon. The program used special rockets called Saturn IB and Saturn V to launch spacecraft into space.

The most famous moment happened during the Apollo 11 mission. Two astronauts, Neil Armstrong and Buzz Aldrin, landed on the Moon and walked on its surface. Another astronaut, Michael Collins, stayed in orbit around the Moon. All three returned safely to Earth on July 24, 1969.

Over the years, Apollo missions brought back many samples of Moon rocks and soil. These samples helped scientists learn more about the Moon. In total, twelve astronauts walked on the Moon during the Apollo program.

Unfortunately, not all missions went as planned. During a test before the first flight, a fire happened and the crew of Apollo 1 could not be saved. Another mission, Apollo 13, faced a problem with an oxygen tank. The crew could not land on the Moon, but they safely returned to Earth using their spacecraft in a clever way.

Uncrewed test flights

From 1961 through 1967, Saturn launch vehicles and Apollo spacecraft parts were tested without astronauts.

The Saturn I rocket was first planned to carry astronauts, but it could not hold enough weight. So, it was used only for testing the rocket and spacecraft parts, along with three small science satellites called Pegasus.

The Saturn IB rocket could carry more weight and was used to test the spacecraft and a moon lander. Several tests were done to make sure everything worked well.

Tests were also done to check a safety system that could quickly get astronauts away from a problem during launch. These tests were done at White Sands Missile Range using a smaller rocket called Little Joe II.

Before 1963, many Saturn V rockets and tests were planned. But a new way of testing was used, which let engineers finish the Saturn V with fewer tests. Three uncrewed test flights were planned for the Saturn V, but after the first two went well, the third was not needed.

Alphabetical mission types

The Apollo program needed to test many parts before sending astronauts to the Moon. In September 1967, Owen Maynard suggested an alphabetical list of mission types. The first two "A-type" missions tested the spacecraft without astronauts. The "C-type" mission, Apollo 7, was the first with astronauts aboard.

Later, the plan changed. Apollo 8, originally a D-type mission, was reclassified to a "C-prime" mission and became the first to send humans to the Moon. Apollo 9 took over the D-type mission, and Apollo 10 was the F-type mission, testing the spacecraft near the Moon but not landing. Apollo 11, the G-type mission, achieved the program's main goal—the first Moon landing.

The list grew to include H-type missions like Apollo 12, 13 (planned), and 14 for precise Moon landings, and J-type missions—Apollo 15, 16, and 17—for detailed scientific study of the Moon from the surface. The I-type mission, planned for extended lunar orbit research, was combined into the J-type missions.

Crewed missions

The Block I spacecraft did not have the ability to fly with the Lunar Module, so the crew positions were called Command Pilot, Senior Pilot, and Pilot, based on U.S. Air Force pilot ratings. The Block II spacecraft was made to fly with the Lunar Module, so the crew positions were called Commander, Command Module Pilot, and Lunar Module Pilot, no matter if a Lunar Module was on the mission or not.

Seven of the missions included times when astronauts went outside the spacecraft, called extravehicular activity (EVA). These were of three types: testing the moonwalking suit in Earth orbit (Apollo 9), exploring the moon’s surface, and getting film canisters from the Scientific Instrument Module stored in the Service Module.

Canceled missions

Main article: Canceled Apollo missions

Several planned Apollo missions were canceled for different reasons, such as changes in how the program would be done, the Apollo 1 fire, delays in making hardware, and limited money.

Before the Apollo 1 fire, two crewed Block I missions were planned, but the second one was canceled because it would not give new information about how the spacecraft worked and could not include activities like spacewalks.

The plan to land on the Moon was successful by the sixth flight, but because people were less interested and money was limited, some missions were canceled. First, Apollo 20 was canceled to free up a rocket to launch the Skylab space station. Later, Apollo 18 and 19 were also canceled to save money and because of worries about more problems with many Moon flights.