The Apollo program was a United States human spaceflight program carried out from 1961 to 1972 by the National Aeronautics and Space Administration (NASA), which landed the first astronauts on the Moon. [1] The program used the Saturn IB and Saturn V launch vehicles to lift the Command/Service Module (CSM) and Lunar Module (LM) spacecraft into space, and the Little Joe II rocket to test a launch escape system which was expected to carry the astronauts to safety in the event of a Saturn failure. [2] Uncrewed test flights beginning in 1966 demonstrated the safety of the launch vehicles and spacecraft to carry astronauts, and four crewed flights beginning in October 1968 demonstrated the ability of the spacecraft to carry out a lunar landing mission.
Apollo achieved the first crewed lunar landing on the Apollo 11 mission, when Neil Armstrong and Buzz Aldrin landed their LM Eagle in the Sea of Tranquility and walked on the lunar surface, while Michael Collins remained in lunar orbit in the CSM Columbia, and all three landed safely on Earth on July 24, 1969. [3] Five subsequent missions landed astronauts on various lunar sites, ending in December 1972 with twelve men having walked on the Moon [4] and 842 pounds (382 kg) of lunar rocks and soil samples returned to Earth, greatly contributing to the understanding of the Moon's composition and geological history. [5]
Two Apollo missions were failures: a 1967 cabin fire killed the entire Apollo 1 crew during a ground test in preparation for what was to be the first crewed flight; [6] and the third landing attempt on Apollo 13 was aborted by an oxygen tank explosion en route to the Moon, which disabled the CSM Odyssey's electrical power and life support systems, and made the propulsion system unsafe to use. The crew circled the Moon and were returned safely to Earth using the LM Aquarius as a "lifeboat" for these functions. [7]
From 1961 through 1967, Saturn launch vehicles and Apollo spacecraft components were tested in uncrewed flights.
The Saturn I launch vehicle was originally planned to carry crewed Command Module flights into low Earth orbit, but its 20,000-pound (9,100 kg) payload capacity limit could not lift even a partially fueled Service Module, which would have required building a lightweight retrorocket module for deorbit. These plans were eventually scrapped, in favor of using the uprated Saturn IB to launch the Command Module with a half-fueled Service Module for crewed Earth orbit tests. This limited Saturn I flights to Saturn launch vehicle development, CSM boilerplate testing, and three micrometeoroid satellite launches in support of Apollo.
Mission | LV | Launch | Pad | Remarks | Refs |
---|---|---|---|---|---|
SA-1 | SA-1 | October 27, 1961, 15:06 | LC-34 | Test of Saturn I first stage S-I; dummy upper stages carried water | [1] [8] [9] |
SA-2 | SA-2 | April 25, 1962, 14:00 | LC-34 | Dummy upper stages released 22,900 U.S. gallons (86,685 L) of water into upper atmosphere, to investigate effects on radio transmission and changes in local weather conditions | [1] [8] [9] |
SA-3 | SA-3 | November 16, 1962, 17:45 | LC-34 | Repeat of SA-2 mission | [1] [8] [9] |
SA-4 | SA-4 | March 28, 1963, 20:11 | LC-34 | Test premature shutdown of a single S-I engine | [1] [8] [9] |
SA-5 | SA-5 | January 29, 1964, 16:25 | LC-37B | First flight of live second stage. First orbital flight. | [1] [8] [9] |
AS-101 | SA-6 | May 28, 1964, 17:07 | LC-37B | Tested first boilerplate Apollo command and service module (CSM) for structural integrity | [1] [9] |
AS-102 | SA-7 | September 18, 1964, 17:22 | LC-37B | Carried first programmable-in-flight computer on the Saturn I vehicle; last launch vehicle development flight | [1] [9] |
AS-103 | SA-9 | February 16, 1965, 14:37 | LC-37B | Carried Pegasus A satellite and boilerplate CSM | [1] [9] |
AS-104 | SA-8 | May 25, 1965, 07:35 | LC-37B | Carried Pegasus B satellite and boilerplate CSM | [1] [9] |
AS-105 | SA-10 | July 30, 1965, 13:00 | LC-37B | Carried Pegasus C satellite and boilerplate CSM | [1] [9] |
There was some incongruity in the numbering and naming of the first three uncrewed Apollo-Saturn (AS), or Apollo flights. This is due to AS-204 being renamed to Apollo 1 posthumously. This crewed flight was to have followed the first three uncrewed flights. After the fire which killed the AS-204 crew on the pad during a test and training exercise, uncrewed Apollo flights resumed to test the Saturn V launch vehicle and the Lunar Module; these were designated Apollo 4, 5 and 6. The first crewed Apollo mission was thus Apollo 7. Simple "Apollo" numbers were never assigned to the first three uncrewed flights, although renaming AS-201, AS-202, and AS-203 as Apollo 1-A, Apollo 2 and Apollo 3, had been briefly considered. [6]
The Saturn I was converted to the Uprated Saturn I, eventually designated Saturn IB, by replacing the S-IV second stage with the S-IVB, which would also be used as the third stage of the Saturn V with the addition of on-orbit restart capability. This increased the payload capacity to 46,000 pounds (21,000 kg), enough to orbit a Command Module with a half-fueled Service Module, and more than enough to orbit a fully fueled Lunar Module.
Two suborbital tests of the Apollo Block I Command and Service Module, one S-IVB development test, and one Lunar Module test were conducted. Success of the LM test led to cancellation of a planned second uncrewed flight.
Mission | LV Serial No | Launch | Remarks | Refs |
---|---|---|---|---|
AS-201 | Saturn IB SA-201 | February 26, 1966, 16:12 GMT Launch Complex 34 | First test of Saturn IB and Block I Apollo CSM. Suborbital flight landed the CM in the Atlantic Ocean, demonstrating the heat shield. Propellant pressure loss caused premature SM engine shutdown. | [1] [6] [8] [9] |
AS-203 | Saturn IB SA-203 | July 5, 1966, 14:53 GMT Launch Complex 37B | No Apollo spacecraft; instrumentation and video observed on-orbit behavior of S-IVB liquid hydrogen fuel in support of restart capability design for Saturn V. Deemed a success, despite inadvertent destruction of S-IVB during final overpressure tank rupture test. | [1] [6] [8] [9] |
AS-202 | Saturn IB SA-202 | August 25, 1966, 17:15 GMT Launch Complex 34 | Suborbital flight to Pacific Ocean splashdown. CM heat shield tested to higher speed; successful SM firings. | [1] [6] [8] [9] |
Apollo 5 | Saturn IB SA-204 | January 22, 1968, 22:48 GMT Launch Complex 37B | First flight of LM successfully fired descent engine and ascent engines; demonstrated "fire-in-the-hole" landing abort test. | [1] [8] [9] |
From August 1963 to January 1966, a number of tests were conducted at the White Sands Missile Range for development of the launch escape system (LES). These included simulated "pad aborts", which might occur while the Apollo-Saturn space vehicle was still on the launch pad, and flights on the Little Joe II rocket to simulate Mode I aborts which might occur while the vehicle was in the air. [1]
Mission | Launch vehicle | Launch | Remarks | Refs |
---|---|---|---|---|
QTV | Little Joe II | August 28, 1963, 13:05 GMT Launch Complex 36 | Little Joe II qualification test | [1] [9] |
Pad Abort Test 1 | None | November 7, 1963, 16:00 GMT Launch Complex 36 | Launch escape system (LES) abort test from launch pad | [1] [9] |
A-001 | Little Joe II | May 13, 1964, 13:00 GMT Launch Complex 36 | LES transonic test, success except for parachute failure | [1] [9] |
A-002 | Little Joe II | December 8, 1964, 15:00 GMT Launch Complex 36 | LES maximum altitude, Max-Q abort test | [1] [9] |
A-003 | Little Joe II | May 19, 1965, 13:01 GMT Launch Complex 36 | LES canard maximum altitude abort test | [1] [9] |
Pad Abort Test 2 | None | June 29, 1965, 13:00 GMT Launch Complex 36 | LES pad abort test of near Block-I CM | [1] [9] |
A-004 | Little Joe II | January 20, 1966, 15:17 GMT Launch Complex 36 | LES test of maximum weight, tumbling Block-I CM | [1] [9] |
Prior to George Mueller's tenure as NASA's Associate Administrator for Manned Space Flight starting in 1963, it was assumed that 20 Saturn Vs, with at least 10 unpiloted test flights, would be required to achieve a crewed Moon landing, using the conservative one-stage-at-a-time testing philosophy used for the Saturn I. But Mueller introduced the "all-up" testing philosophy of using three live stages plus the Apollo spacecraft on every test flight. This achieved development of the Saturn V with far fewer uncrewed tests, and facilitated achieving the Moon landing by the 1969 goal. The size of the Saturn V production lot was reduced from 20 to 15 units. [10]
Three uncrewed test flights were planned to human-rate the super heavy-lift Saturn V which would take crewed Apollo flights to the Moon. Success of the first flight and qualified success of the second led to the decision to cancel the third uncrewed test.
Mission | LV Serial No | Launch | Remarks | Refs |
---|---|---|---|---|
Apollo 4 | Saturn V SA-501 | November 9, 1967, 12:00 GMT Launch Complex 39A | First flight of Saturn V rocket; successfully demonstrated S-IVB third stage restart and tested CM heat shield at lunar re-entry speeds. | [1] [8] [9] |
Apollo 6 | Saturn V SA-502 | April 4, 1968, 16:12 GMT Launch Complex 39A | Second flight of Saturn V; severe "pogo" vibrations caused two second-stage engines to shut down prematurely, and third stage restart to fail. SM engine used to achieve high-speed re-entry, though less than Apollo 4. NASA identified vibration fixes and declared Saturn V man-rated. | [1] [8] [9] |
The Apollo program required sequential testing of several major mission elements in the runup to a crewed lunar landing. An alphabetical list of major mission types was proposed by Owen Maynard in September 1967. [11] [12] Two "A-type" missions performed uncrewed tests of the CSM and the Saturn V, and one B-type mission performed an uncrewed test of the LM. The C-type mission, the first crewed flight of the CSM in Earth orbit, was performed by Apollo 7.
The list was revised upon George Low's proposal to commit a mission to lunar orbit ahead of schedule, an idea influenced by the status of the CSM as a proven craft and production delays of the LM. [13] Apollo 8 was reclassified from its original assignment as a D-type mission, a test of the complete CSM/LM spacecraft in Earth orbit, to a "C-prime" mission which would fly humans to the Moon. Once complete, it obviated the need for the E-type objective of a medium Earth orbital test. The D-type mission was instead performed by Apollo 9; the F-type mission, Apollo 10, flew the CSM/LM spacecraft to the Moon for final testing, without landing. The G-type mission, Apollo 11, performed the first lunar landing, the central goal of the program.
The initial A–G [11] [14] list was expanded to include later mission types: [1] : 466 H-type missions—Apollo 12, 13 (planned) and 14—would perform precision landings, and J-type missions—Apollo 15, 16 and 17—would perform thorough scientific investigation. The I-type objective, which called for extended lunar orbital surveillance of the Moon, [15] was incorporated into the J-type missions. [1] : 466
Mission type | Missions | Description |
---|---|---|
A | Uncrewed flights of launch vehicles and the CSM, to demonstrate its design and to certify its safety for humans. [14] [a] | |
B | Apollo 5 | Uncrewed flight of the LM, to demonstrate its design and to certify its safety for humans. [14] |
C | Apollo 7 | Crewed flight demonstration of CSM in low Earth orbit. [14] |
C′ | Apollo 8 | Crewed flight demonstration of CSM in lunar orbit. [1] : 466 |
D | Apollo 9 | Crewed flight demonstration of CSM and LM in low Earth orbit, operating the equipment together in space and (insofar as possible in Earth orbit) performing the maneuvers involved in a lunar landing. [14] |
E | — | Crewed flight demonstration of CSM and LM in medium Earth orbit, performing the maneuvers involved in a lunar landing. [14] |
F | Apollo 10 | Crewed flight demonstration of CSM and LM in lunar orbit, performing all G-type mission goals except for the final descent to and landing on the lunar surface. [14] |
G | Apollo 11 | Crewed lunar landing demonstration. [1] : 466 |
H | Precision crewed lunar landing demonstration and systematic lunar exploration. [1] : 466 | |
I | — | Reserved for lunar survey missions. (Not used) [15] |
J | Extended scientific investigation of the Moon on the lunar surface and from lunar orbit. [1] : 466 |
The Block I CSM spacecraft did not have capability to fly with the LM, and the three crew positions were designated Command Pilot, Senior Pilot, and Pilot, based on U.S. Air Force pilot ratings. The Block II spacecraft was designed to fly with the Lunar Module, so the corresponding crew positions were designated Commander, Command Module Pilot, and Lunar Module Pilot regardless of whether a Lunar Module was present or not on any mission. [16]
Seven of the missions involved extravehicular activity (EVA), spacewalks or moonwalks outside of the spacecraft. These were of three types: testing the lunar EVA suit in Earth orbit (Apollo 9), exploring the lunar surface, and retrieving film canisters from the Scientific Instrument Module stored in the Service Module. [17]
Mission | Patch | Launch date | Crew | Launch vehicle [b] | CM name | LM name | Duration | Remarks | Refs |
---|---|---|---|---|---|---|---|---|---|
Apollo 1 | February 21, 1967 Launch Complex 34 (planned) | Gus Grissom Ed White Roger B. Chaffee | Saturn IB (SA-204) | — | — | — | Never launched. On January 27, 1967, a fire in the command module during a launch pad test killed the crew and destroyed the module. This flight was originally designated AS-204, and was renamed to Apollo 1 at the request of the crew's families. | [1] [8] [18] [19] [20] | |
Apollo 7 | October 11, 1968, 15:02 GMT Launch Complex 34 | Wally Schirra Donn F. Eisele Walter Cunningham | Saturn IB (AS-205) | — | — | 10 d 20 h 09 m 03 s | Test flight of Block II CSM in Earth orbit; included first live TV broadcast from American spacecraft. | [1] [8] [21] [22] [23] | |
Apollo 8 | December 21, 1968, 12:51 GMT Launch Complex 39A | Frank Borman James Lovell William Anders | Saturn V (SA-503) | — | — | 06 d 03 h 00 m 42 s | First humans to leave Earth orbit and first to arrive at the Moon, first circumlunar flight of CSM, had ten lunar orbits in 20 hours. First crewed flight of Saturn V. | [1] [8] [24] [25] [26] | |
Apollo 9 | March 3, 1969, 16:00 GMT Launch Complex 39A | James McDivitt David Scott Rusty Schweickart | Saturn V (SA-504) | Gumdrop | Spider | 10 d 01 h 00 m 54 s | First crewed flight test of Lunar Module; tested propulsion, rendezvous and docking in Earth orbit. EVA tested the Portable Life Support System (PLSS). | [1] [8] [27] [28] [29] | |
Apollo 10 | May 18, 1969, 16:49 GMT Launch Complex 39B | Thomas P. Stafford John Young Eugene Cernan | Saturn V (SA-505) | Charlie Brown | Snoopy | 08 d 00 h 03 m 23 s | "Dress rehearsal" for lunar landing. The LM descended to 8.4 nautical miles (15.6 km) from lunar surface. | [1] [8] [30] [31] [32] | |
Apollo 11 | July 16, 1969, 13:32 GMT Launch Complex 39A | Neil Armstrong Michael Collins Edwin "Buzz" Aldrin | Saturn V (SA-506) | Columbia | Eagle | 08 d 03 h 18 m 35 s | First crewed landing in Sea of Tranquility (Tranquility Base) including a single surface EVA. | [1] [8] [3] [33] | |
Apollo 12 | November 14, 1969, 16:22 GMT Launch Complex 39A | Charles (Pete) Conrad Richard F. Gordon Jr. Alan Bean | Saturn V (SA-507) | Yankee Clipper | Intrepid | 10 d 04 h 36 m 24 s | First precise Moon landing in Ocean of Storms near Surveyor 3 probe. Two surface EVAs and returned parts of Surveyor to Earth. | [1] [8] [34] [35] | |
Apollo 13 | April 11, 1970, 19:13 GMT Launch Complex 39A | James Lovell Jack Swigert Fred Haise | Saturn V (SA-508) | Odyssey | Aquarius | 05 d 22 h 54 m 41 s | Intended Fra Mauro landing cancelled after SM oxygen tank exploded. LM used as "lifeboat" for safe crew return. First S-IVB stage impact on Moon for active seismic test. | [1] [8] [36] [7] | |
Apollo 14 | January 31, 1971, 21:03 GMT Launch Complex 39A | Alan Shepard Stuart Roosa Edgar Mitchell | Saturn V (SA-509) | Kitty Hawk | Antares | 09 d 00 h 01 m 58 s | Successful Fra Mauro landing. Broadcast first color TV images from lunar surface (other than a few moments at the start of the Apollo 12 moonwalk.) Conducted first materials science experiments in space. Conducted two surface EVAs. | [1] [8] [37] [38] | |
Apollo 15 | July 26, 1971, 13:34 GMT Launch Complex 39A | David Scott Alfred Worden James Irwin | Saturn V (SA-510) | Endeavour | Falcon | 12 d 07 h 11 m 53 s | Landing at Hadley–Apennine. First extended LM, three-day lunar stay. First use of Lunar Roving Vehicle. Conducted three lunar surface EVAs and one deep space EVA on return to retrieve orbital camera film from SM. | [1] [8] [39] [40] | |
Apollo 16 | April 16, 1972, 17:54 GMT Launch Complex 39A | John Young Ken Mattingly Charles Duke | Saturn V (SA-511) | Casper | Orion | 11 d 01 h 51 m 05 s | Landing in Descartes Highlands. Conducted three lunar EVAs and one deep space EVA. | [1] [8] [41] [42] | |
Apollo 17 | December 7, 1972, 05:33 GMT Launch Complex 39A | Eugene Cernan Ronald Evans Harrison Schmitt | Saturn V (SA-512) | America | Challenger | 12d 13 h 51 m 59 s | Landing at Taurus–Littrow. First professional geologist on the Moon. First night launch. Conducted three lunar EVAs and one deep space EVA. | [1] [8] [9] [43] |
Several planned missions of the Apollo program were canceled for a variety of reasons, including changes in technical direction, the Apollo 1 fire, hardware delays, and budget limitations.
As planned | As flown | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Mission | Type | Date | Landing site | CDR | CMP | LMP | Mission | Launch date | Landing site | CDR | CMP | LMP |
Apollo 12 [c] | H | November 1969 | Ocean of Storms | Pete Conrad | Richard F. Gordon Jr. | Alan Bean | Apollo 12 | November 14, 1969 | Ocean of Storms | Pete Conrad | Richard F. Gordon Jr. | Alan Bean |
Apollo 13 | H | March 1970 | Fra Mauro highlands | Alan Shepard | Stuart Roosa | Edgar Mitchell | Apollo 13 | April 11, 1970 | Failed | Jim Lovell | Jack Swigert | Fred Haise |
Apollo 14 | H | July 1970 | Censorinus crater | Jim Lovell | Ken Mattingly | Fred Haise | Apollo 14 | January 31, 1971 | Fra Mauro highlands | Alan Shepard | Stuart Roosa | Edgar Mitchell |
Apollo 15 | H | November 1970 | Littrow crater | David Scott | Alfred Worden | James Irwin | Apollo 15 | July 26, 1971 | Hadley Rille | David Scott | Alfred Worden | James Irwin |
Apollo 16 | J | April 1971 | Tycho crater | John Young | Jack Swigert | Charles Duke | Apollo 16 | April 16, 1972 | Descartes Highlands | John Young | Ken Mattingly | Charles Duke |
Apollo 17 | J | September 1971 | Marius Hills | Gene Cernan | Ronald Evans | Joe Engle | Apollo 17 | December 7, 1972 | Taurus-Littrow | Gene Cernan | Ronald Evans | Harrison Schmitt |
Apollo 18 | J | February 1972 | Schroter's Valley | Richard F. Gordon Jr. | Vance Brand | Harrison Schmitt | CANCELED September 1970 | |||||
Apollo 19 | J | July 1972 | Hyginus Rille | Fred Haise | William Pogue | Gerald Carr | CANCELED September 1970 | |||||
Apollo 20 | J | December 1972 | Copernicus crater | Stuart Roosa | Don L. Lind | Jack Lousma | CANCELED January 4, 1970 |
There were two NASA post-Apollo crewed spaceflight programs that used Apollo hardware: [48]
Apollo 8 was the first crewed spacecraft to leave Earth's gravitational sphere of influence, and the first human spaceflight to reach the Moon. The crew orbited the Moon ten times without landing and then returned to Earth. The three astronauts—Frank Borman, James Lovell, and William Anders—were the first humans to see and photograph the far side of the Moon and an Earthrise.
The Apollo program, also known as Project Apollo, was the United States human spaceflight program carried out by the National Aeronautics and Space Administration (NASA), which succeeded in preparing and landing the first men on the Moon in 1969. It was first conceived in 1960 during President Dwight D. Eisenhower's administration as a three-person spacecraft to follow the one-person Project Mercury, which put the first Americans in space. Apollo was later dedicated to President John F. Kennedy's national goal for the 1960s of "landing a man on the Moon and returning him safely to the Earth" in an address to Congress on May 25, 1961. It was the third US human spaceflight program to fly, preceded by the two-person Project Gemini conceived in 1961 to extend spaceflight capability in support of Apollo.
Apollo 13 was the seventh crewed mission in the Apollo space program and would have been the third Moon landing. The craft was launched from Kennedy Space Center on April 11, 1970, but the landing was aborted after an oxygen tank in the service module (SM) exploded two days into the mission, disabling its electrical and life-support system. The crew, supported by backup systems on the lunar module (LM), instead looped around the Moon in a circumlunar trajectory and returned safely to Earth on April 17. The mission was commanded by Jim Lovell, with Jack Swigert as command module (CM) pilot and Fred Haise as lunar module (LM) pilot. Swigert was a late replacement for Ken Mattingly, who was grounded after exposure to rubella.
Apollo 7 was the first crewed flight in NASA's Apollo program, and saw the resumption of human spaceflight by the agency after the fire that had killed the three Apollo 1 astronauts during a launch rehearsal test on January 27, 1967. The Apollo 7 crew was commanded by Walter M. Schirra, with command module pilot Donn F. Eisele and Lunar Module pilot R. Walter Cunningham.
Apollo 9 was the third human spaceflight in NASA's Apollo program. Flown in low Earth orbit, it was the second crewed Apollo mission that the United States launched via a Saturn V rocket, and was the first flight of the full Apollo spacecraft: the command and service module (CSM) with the Lunar Module (LM). The mission was flown to qualify the LM for lunar orbit operations in preparation for the first Moon landing by demonstrating its descent and ascent propulsion systems, showing that its crew could fly it independently, then rendezvous and dock with the CSM again, as would be required for the first crewed lunar landing. Other objectives of the flight included firing the LM descent engine to propel the spacecraft stack as a backup mode, and use of the portable life support system backpack outside the LM cabin.
Apollo 10 was the fourth human spaceflight in the United States' Apollo program and the second to orbit the Moon. NASA, the mission's operator, described it as a "dress rehearsal" for the first Moon landing. It was designated an "F" mission, intended to test all spacecraft components and procedures short of actual descent and landing.
Apollo 12 was the sixth crewed flight in the United States Apollo program and the second to land on the Moon. It was launched on November 14, 1969, by NASA from the Kennedy Space Center, Florida. Commander Charles "Pete" Conrad and Lunar Module Pilot Alan L. Bean completed just over one day and seven hours of lunar surface activity while Command Module Pilot Richard F. Gordon remained in lunar orbit.
Apollo 15 was the ninth crewed mission in the Apollo program and the fourth Moon landing. It was the first J mission, with a longer stay on the Moon and a greater focus on science than earlier landings. Apollo 15 saw the first use of the Lunar Roving Vehicle.
Apollo 16 was the tenth crewed mission in the United States Apollo space program, administered by NASA, and the fifth and penultimate to land on the Moon. It was the second of Apollo's "J missions", with an extended stay on the lunar surface, a focus on science, and the use of the Lunar Roving Vehicle (LRV). The landing and exploration were in the Descartes Highlands, a site chosen because some scientists expected it to be an area formed by volcanic action, though this proved not to be the case.
Apollo 17 was the eleventh and final mission of NASA's Apollo program, the sixth and most recent time humans have set foot on the Moon or traveled beyond low Earth orbit. Commander Gene Cernan and Lunar Module Pilot Harrison Schmitt walked on the Moon, while Command Module Pilot Ronald Evans orbited above. Schmitt was the only professional geologist to land on the Moon; he was selected in place of Joe Engle, as NASA had been under pressure to send a scientist to the Moon. The mission's heavy emphasis on science meant the inclusion of a number of new experiments, including a biological experiment containing five mice that was carried in the command module.
The Apollo Lunar Module, originally designated the Lunar Excursion Module (LEM), was the lunar lander spacecraft that was flown between lunar orbit and the Moon's surface during the United States' Apollo program. It was the first crewed spacecraft to operate exclusively in the airless vacuum of space, and remains the only crewed vehicle to land anywhere beyond Earth.
Apollo 4, also known as SA-501, was the uncrewed first test flight of the Saturn V launch vehicle, the rocket that eventually took astronauts to the Moon. The space vehicle was assembled in the Vehicle Assembly Building, and was the first to be launched from Kennedy Space Center (KSC) in Florida, ascending from Launch Complex 39, where facilities built specially for the Saturn V had been constructed.
Apollo 5, also known as AS-204, was the uncrewed first flight of the Apollo Lunar Module (LM) that would later carry astronauts to the surface of the Moon. The Saturn IB rocket bearing the LM lifted off from Cape Kennedy on January 22, 1968. The mission was successful, though due to programming problems an alternate mission to that originally planned was executed.
Apollo 6, also known as AS-502, was the third and final uncrewed flight in the United States' Apollo Program and the second test of the Saturn V launch vehicle. It qualified the Saturn V for use on crewed missions, and it was used beginning with Apollo 8 in December 1968.
The Apollo spacecraft was composed of three parts designed to accomplish the American Apollo program's goal of landing astronauts on the Moon by the end of the 1960s and returning them safely to Earth. The expendable (single-use) spacecraft consisted of a combined command and service module (CSM) and an Apollo Lunar Module (LM). Two additional components complemented the spacecraft stack for space vehicle assembly: a spacecraft–LM adapter (SLA) designed to shield the LM from the aerodynamic stress of launch and to connect the CSM to the Saturn launch vehicle and a launch escape system (LES) to carry the crew in the command module safely away from the launch vehicle in the event of a launch emergency.
The Saturn IB was an American launch vehicle commissioned by the National Aeronautics and Space Administration (NASA) for the Apollo program. It uprated the Saturn I by replacing the S-IV second stage, with the S-IVB. The S-IB first stage also increased the S-I baseline's thrust from 1,500,000 pounds-force (6,700,000 N) to 1,600,000 pounds-force (7,100,000 N) and propellant load by 3.1%. This increased the Saturn I's low Earth orbit payload capability from 20,000 pounds (9,100 kg) to 46,000 pounds (21,000 kg), enough for early flight tests of a half-fueled Apollo command and service module (CSM) or a fully fueled Apollo Lunar Module (LM), before the larger Saturn V needed for lunar flight was ready.
The Apollo command and service module (CSM) was one of two principal components of the United States Apollo spacecraft, used for the Apollo program, which landed astronauts on the Moon between 1969 and 1972. The CSM functioned as a mother ship, which carried a crew of three astronauts and the second Apollo spacecraft, the Apollo Lunar Module, to lunar orbit, and brought the astronauts back to Earth. It consisted of two parts: the conical command module, a cabin that housed the crew and carried equipment needed for atmospheric reentry and splashdown; and the cylindrical service module which provided propulsion, electrical power and storage for various consumables required during a mission. An umbilical connection transferred power and consumables between the two modules. Just before reentry of the command module on the return home, the umbilical connection was severed and the service module was cast off and allowed to burn up in the atmosphere.
The Apollo Applications Program (AAP) was created as early as 1966 by NASA headquarters to develop science-based human spaceflight missions using hardware developed for the Apollo program. AAP was the ultimate development of a number of official and unofficial Apollo follow-on projects studied at various NASA labs. However, the AAP's ambitious initial plans became an early casualty when the Johnson Administration declined to support it adequately, partly in order to implement its Great Society set of domestic programs while remaining within a $100 billion budget. Thus, Fiscal Year 1967 ultimately allocated $80 million to the AAP, compared to NASA's preliminary estimates of $450 million necessary to fund a full-scale AAP program for that year, with over $1 billion being required for FY 1968. The AAP eventually led to Skylab, which absorbed much of what had been developed under Apollo Applications.
Several planned missions of the Apollo crewed Moon landing program of the 1960s and 1970s were canceled, for reasons which included changes in technical direction, the Apollo 1 fire, the Apollo 13 incident, hardware delays, and budget limitations. After the landing by Apollo 12, Apollo 20, which would have been the final crewed mission to the Moon, was canceled to allow Skylab to launch as a "dry workshop". The next two missions, Apollos 18 and 19, were later canceled after the Apollo 13 incident and further budget cuts. Two Skylab missions also ended up being canceled. Two complete Saturn V rockets remained unused and were put on display in the United States.