Government landings

Six government space agencies, Interkosmos, NASA, CNSA, ISRO, JAXA and ESA, have reached the Moon with uncrewed missions. Three private/commercial missions, Beresheet (hard landing), Hakuto-R (hard landing), and Odysseus (soft landing) have also reached the lunar surface (see #Commercial landings). The Soviet Union (Interkosmos), the United States (NASA), China (CNSA), India (ISRO),^[6] and Japan (JAXA)^[7] are the only five nations to have successfully achieved soft landings.

The Soviet Union performed the first hard Moon landing – "hard" meaning the spacecraft intentionally crashes into the Moon at high speeds – with the Luna 2 spacecraft in 1959, a feat the U.S. duplicated in 1962 with Ranger 4.

Following their initial hard landings on the Moon, sixteen Soviet, U.S., Chinese and Indian spacecraft have used braking rockets (retrorockets) to make soft landings and perform scientific operations on the lunar surface. In 1966 the Soviet Union accomplished the first soft landings and took the first pictures from the lunar surface during the Luna 9 and Luna 13 missions. The U.S. followed with five Surveyor soft landings. China's ongoing "Chang'e" program has landed 3 times since 2013, achieving soil sample return and the first landing on the far side of the Moon.

On 23 August 2023, ISRO successfully landed its Chandrayaan-3 module in the lunar south pole region, making India the fourth nation to successfully complete a soft landing on the Moon.^[8] Chandrayaan-3 saw a successful soft landing of its Vikram lander and Pragyan rover at 6.04 pm IST (1234 GMT), marking the first uncrewed soft landing in the little-explored region.^[9]

On 19 January 2024, JAXA successfully landed its SLIM lander, making Japan the fifth nation to successfully complete a soft landing.^[10]

Commercial landings

Two organizations have attempted but failed to achieve soft landings: Israeli private space agency SpaceIL with their Beresheet spacecraft (2019), and Japanese company ispace's Hakuto-R Mission 1 (2023).

On 22 February 2024, Intuitive Machine's Odysseus successfully landed on the Moon after taking off on a SpaceX Falcon 9 liftoff on 15 February 2024 in a mission between NASA, SpaceX, and Intuitive Machines, marking the United States' first soft unmanned moon landing in over 50 years. This event marked the first successful landing of a privately owned spacecraft on the Moon.^[11][12]

Pioneer missions

Three different designs of Pioneer lunar probes were flown on three different modified ICBMs. Those flown on the Thor booster modified with an Able upper stage carried an infrared image scanning television system with a resolution of 1 milliradian to study the Moon's surface, an ionization chamber to measure radiation in space, a diaphragm/microphone assembly to detect micrometeorites, a magnetometer, and temperature-variable resistors to monitor spacecraft internal thermal conditions.^[27][28][29] The first, a mission managed by the United States Air Force, exploded during launch;^[27] all subsequent Pioneer lunar flights had NASA as the lead management organization. The next two returned to Earth and burned up upon reentry into the atmosphere after achieved maximum altitudes of around 114,000 kilometres (71,000 mi)^[28] and 1,530 kilometres (950 mi)^[29] respectively, far short of the roughly 400,000 kilometres (250,000 mi) required to reach the vicinity of the Moon.

NASA then collaborated with the United States Army's Ballistic Missile Agency to fly two extremely small cone-shaped probes on the Juno ICBM, carrying only photocells which would be triggered by the light of the Moon and a lunar radiation environment experiment using a Geiger-Müller tube detector.^[30][31] The first of these reached an altitude of only around 100,000 kilometres (62,000 mi), gathering data that established the presence of the Van Allen radiation belts before reentering Earth's atmosphere.^[30] The second passed by the Moon at a distance of more than 60,000 kilometres (37,000 mi), twice as far as planned and too far away to trigger either of the on-board scientific instruments, yet still becoming the first U.S. spacecraft to reach a solar orbit.^[31]

The final Pioneer lunar probe design consisted of four "paddlewheel" solar panels extending from a one-meter diameter spherical spin-stabilized spacecraft body equipped to take images of the lunar surface with a television-like system, estimate the Moon's mass and topography of the poles, record the distribution and velocity of micrometeorites, study radiation, measure magnetic fields, detect low frequency electromagnetic waves in space and use a sophisticated integrated propulsion system for maneuvering and orbit insertion as well.^[32] None of the four spacecraft built in this series of probes survived launch on its Atlas ICBM outfitted with an Able upper stage.^[33][34][35]

Following the unsuccessful Atlas-Able Pioneer probes, NASA's Jet Propulsion Laboratory embarked upon an uncrewed spacecraft development program whose modular design could be used to support both lunar and interplanetary exploration missions. The interplanetary versions were known as Mariners;^[36] lunar versions were Rangers. JPL envisioned three versions of the Ranger lunar probes: Block I prototypes, which would carry various radiation detectors in test flights to a very high Earth orbit that came nowhere near the Moon;^[37] Block II, which would try to accomplish the first Moon landing by hard landing a seismometer package;^[38] and Block III, which would crash onto the lunar surface without any braking rockets while taking very high resolution wide-area photographs of the Moon during their descent.^[39]

Ranger missions

The Ranger 1 and 2 Block I missions were virtually identical.^[40][41] Spacecraft experiments included a Lyman-alpha telescope, a rubidium-vapor magnetometer, electrostatic analyzers, medium-energy-range particle detectors, two triple coincidence telescopes, a cosmic-ray integrating ionization chamber, cosmic dust detectors, and scintillation counters. The goal was to place these Block I spacecraft in a very high Earth orbit with an apogee of 110,000 kilometres (68,000 mi) and a perigee of 60,000 kilometres (37,000 mi).^[40]

From that vantage point, scientists could make direct measurements of the magnetosphere over a period of many months while engineers perfected new methods to routinely track and communicate with spacecraft over such large distances. Such practice was deemed vital to be assured of capturing high-bandwidth television transmissions from the Moon during a one-shot fifteen-minute time window in subsequent Block II and Block III lunar descents. Both Block I missions suffered failures of the new Agena upper stage and never left low Earth parking orbit after launch; both burned up upon reentry after only a few days.

The first attempts to perform a Moon landing took place in 1962 during the Rangers 3, 4 and 5 missions flown by the United States.^[13][21][23] All three Block II missions basic vehicles were 3.1 m high and consisted of a lunar capsule covered with a balsa wood impact-limiter, 650 mm in diameter, a mono-propellant mid-course motor, a retrorocket with a thrust of 5,050 pounds-force (22.5 kN),^[21] and a gold- and chrome-plated hexagonal base 1.5 m in diameter. This lander (code-named Tonto) was designed to provide impact cushioning using an exterior blanket of crushable balsa wood and an interior filled with incompressible liquid freon. A 42-kilogram (93 lb) 30-centimetre-diameter (0.98 ft) metal payload sphere floated and was free to rotate in a liquid freon reservoir contained in the landing sphere.^[42]

This payload sphere contained six silver-cadmium batteries to power a fifty-milliwatt radio transmitter, a temperature sensitive voltage controlled oscillator to measure lunar surface temperatures, and a seismometer designed with sensitivity high enough to detect the impact of a 2.3 kg (5 lb) meteorite on the opposite side of the Moon. Weight was distributed in the payload sphere so it would rotate in its liquid blanket to place the seismometer into an upright and operational position no matter what the final resting orientation of the external landing sphere. After landing, plugs were to be opened allowing the freon to evaporate and the payload sphere to settle into upright contact with the landing sphere. The batteries were sized to allow up to three months of operation for the payload sphere. Various mission constraints limited the landing site to Oceanus Procellarum on the lunar equator, which the lander ideally would reach 66 hours after launch.

No cameras were carried by the Ranger landers, and no pictures were to be captured from the lunar surface during the mission. Instead, the 3.1 metres (10 ft) Ranger Block II mother ship carried a 200-scan-line television camera to capture images during the free-fall descent to the lunar surface. The camera was designed to transmit a picture every 10 seconds.^[21] Seconds before impact, at 5 and 0.6 kilometres (3.11 and 0.37 mi) above the lunar surface, the Ranger mother ships took pictures (which may be viewed here).

Other instruments gathering data before the mother ship crashed onto the Moon were a gamma ray spectrometer to measure overall lunar chemical composition and a radar altimeter. The radar altimeter was to give a signal ejecting the landing capsule and its solid-fueled braking rocket overboard from the Block II mother ship. The braking rocket was to slow and the landing sphere to a dead stop at 330 metres (1,080 ft) above the surface and separate, allowing the landing sphere to free fall once more and hit the surface.^[44]

On Ranger 3, failure of the Atlas guidance system and a software error aboard the Agena upper stage combined to put the spacecraft on a course that would miss the Moon. Attempts to salvage lunar photography during a flyby of the Moon were thwarted by in-flight failure of the onboard flight computer. This was probably because of prior heat sterilization of the spacecraft by keeping it above the boiling point of water for 24 hours on the ground, to protect the Moon from being contaminated by Earth organisms. Ranger 3 later began orbiting the Sun, called heliocentric orbit.^[45] Heat sterilization was also blamed for subsequent in-flight failures of the spacecraft computer on Ranger 4 and the power subsystem on Ranger 5. Only Ranger 4 reached the Moon in an uncontrolled crash impact on the far side of the Moon.^[46]

Block III probes replaced the Block II landing capsule and its retrorocket with a heavier, more capable television system to support landing site selection for upcoming Apollo crewed Moon landing missions. Six cameras were designed to take thousands of high-altitude photographs in the final twenty-minute period before crashing on the lunar surface. Camera resolution was 1,132 scan lines, far higher than the 525 lines found in a typical U.S. 1964 home television. While Ranger 6 suffered a failure of this camera system and returned no photographs despite an otherwise successful flight, the subsequent Ranger 7 mission to Mare Cognitum was a complete success.

Breaking the six-year string of failures in U.S. attempts to photograph the Moon at close range, the Ranger 7 mission was viewed as a national turning point and instrumental in allowing the key 1965 NASA budget appropriation to pass through the United States Congress intact without a reduction in funds for the Apollo crewed Moon landing program. Subsequent successes with Ranger 8 and Ranger 9 further buoyed U.S. hopes.

US strategy

Plans for human Moon exploration began during the Eisenhower administration. In a series of mid-1950s articles in Collier's magazine, Wernher von Braun had popularized the idea of a crewed expedition to establish a lunar base. A human Moon landing posed several daunting technical challenges to the US and USSR. Besides guidance and weight management, atmospheric re-entry without ablative overheating was a major hurdle. After the Soviets launched Sputnik, von Braun promoted a plan for the US Army to establish a military lunar outpost by 1965.

After the early Soviet successes, especially Yuri Gagarin's flight, US President John F. Kennedy looked for a project that would capture the public imagination. He asked Vice President Lyndon Johnson to make recommendations on a scientific endeavor that would prove US world leadership. The proposals included non-space options such as massive irrigation projects to benefit the Third World. The Soviets, at the time, had more powerful rockets than the US, which gave them an advantage in some kinds of space mission.

Advances in US nuclear weapon technology had led to smaller, lighter warheads; the Soviets' were much heavier, and the powerful R-7 rocket was developed to carry them. More modest missions such as flying around the Moon, or a space lab in lunar orbit (both were proposed by Kennedy to von Braun), offered too much advantage to the Soviets; landing, however, would capture the world's imagination.

Johnson had championed the US human spaceflight program ever since Sputnik, sponsoring legislation to create NASA while he was still a senator. When Kennedy asked him in 1961 to research the best achievement to counter the Soviets' lead, Johnson responded that the US had an even chance of beating them to a crewed lunar landing, but not for anything less. Kennedy seized on Apollo as the ideal focus for efforts in space. He ensured continuing funding, shielding space spending from the 1963 tax cut, but diverting money from other NASA scientific projects. These diversions dismayed NASA's leader, James E. Webb, who perceived the need for NASA's support from the scientific community.

The Moon landing required development of the large Saturn V launch vehicle, which achieved a perfect record: zero catastrophic failures or launch vehicle-caused mission failures in thirteen launches.

For the program to succeed, its proponents would have to defeat criticism from politicians both on the left (more money for social programs) and on the right (more money for the military). By emphasizing the scientific payoff and playing on fears of Soviet space dominance, Kennedy and Johnson managed to swing public opinion: by 1965, 58 percent of Americans favored Apollo, up from 33 percent two years earlier. After Johnson became President in 1963, his continuing defense of the program allowed it to succeed in 1969, as Kennedy had planned.

Soviet strategy

Soviet leader Nikita Khrushchev said in October 1963 the USSR was "not at present planning flight by cosmonauts to the Moon," while insisting that the Soviets had not dropped out of the race. Only after another year did the USSR fully commit itself to a Moon-landing attempt, which ultimately failed.

At the same time, Kennedy had suggested various joint programs, including a possible Moon landing by Soviet and U.S. astronauts and the development of better weather-monitoring satellites, eventually resulting in the Apollo-Soyuz mission. Khrushchev, sensing an attempt by Kennedy to steal Russian space technology, rejected the idea at first: if the USSR went to the Moon, it would go alone. Though Khrushchev was eventually warming up to the idea, the realization of a joint Moon landing was choked by Kennedy's assassination.^[50]

Sergey Korolev, the Soviet space program's chief designer, had started promoting his Soyuz craft and the N1 launcher rocket that would have the capability of carrying out a human Moon landing. Khrushchev directed Korolev's design bureau to arrange further space firsts by modifying the existing Vostok technology, while a second team started building a completely new launcher and craft, the Proton booster and the Zond, for a human cislunar flight in 1966. In 1964 the new Soviet leadership gave Korolev the backing for a Moon landing effort and brought all crewed projects under his direction.

With Korolev's death and the failure of the first Soyuz flight in 1967, coordination of the Soviet Moon landing program quickly unraveled. The Soviets built a landing craft and selected cosmonauts for a mission that would have placed Alexei Leonov on the Moon's surface, but with the successive launch failures of the N1 booster in 1969, plans for a crewed landing suffered first delay and then cancellation.

A program of automated return vehicles was begun, in the hope of being the first to return lunar rocks. This had several failures. It eventually succeeded with Luna 16 in 1970.^[51] But this had little impact, because the Apollo 11 and Apollo 12 lunar landings and rock returns had already taken place by then.

Apollo missions

In total, twenty-four U.S. astronauts have traveled to the Moon. Three have made the trip twice, and twelve have walked on its surface. Apollo 8 was a lunar-orbit-only mission, Apollo 10 included undocking and Descent Orbit Insertion (DOI), followed by LM staging to CSM redocking, while Apollo 13, originally scheduled as a landing, ended up as a lunar fly-by, by means of free return trajectory; thus, none of these missions made landings. Apollo 7 and Apollo 9 were Earth-orbit-only missions. Apart from the inherent dangers of crewed Moon expeditions as seen with Apollo 13, one reason for their cessation according to astronaut Alan Bean is the cost it imposes in government subsidies.^[52]

Human Moon landings

Other aspects of the successful Apollo landings

President Richard Nixon had speechwriter William Safire prepare a condolence speech for delivery in case Armstrong and Aldrin became marooned on the Moon's surface and could not be rescued.^[53]

In 1951, science fiction writer Arthur C. Clarke forecast that a man would reach the Moon by 1978.^[54]

On 16 August 2006, the Associated Press reported that NASA is missing the original Slow-scan television tapes (which were made before the scan conversion for conventional TV) of the Apollo 11 Moon walk. Some news outlets have mistakenly reported the SSTV tapes found in Western Australia, but those tapes were only recordings of data from the Apollo 11 Early Apollo Surface Experiments Package.^[55] The tapes were found in 2008 and sold at auction in 2019 for the 50th anniversary of the landing.^[56]

Scientists believe the six American flags planted by astronauts have been bleached white because of more than 40 years of exposure to solar radiation.^[57] Using LROC images, it has been determined that five of the six American flags are still standing and casting shadows at all of the sites, except Apollo 11.^[58] Astronaut Buzz Aldrin reported that the flag was blown over by the exhaust from the ascent engine during liftoff of Apollo 11.^[58]

Hiten (Japan)

Launched on 24 January 1990, 11:46 UTC. At the end of its mission, the Japanese lunar orbiter Hiten was commanded to crash into the lunar surface and did so on 10 April 1993 at 18:03:25.7 UT (11 April 03:03:25.7 JST).^[59]

Lunar Prospector (U.S.)

Lunar Prospector was launched on 7 January 1998. The mission ended on 31 July 1999, when the orbiter was deliberately crashed into a crater near the lunar south pole after the presence of water ice was successfully detected.^[60]

SMART-1 (ESA)

Launched 27 September 2003, 23:14 UTC from the Guiana Space Centre in Kourou, French Guiana. At the end of its mission, the ESA lunar orbiter SMART-1 performed a controlled crash into the Moon, at about 2 km/s (7,200 km/h; 4,500 mph). The time of the crash was 3 September 2006, at 5:42 UTC.^[61]

Chandrayaan-1 (India)

The Indian Space Research Organisation (ISRO) performed a controlled hard landing with its Moon Impact Probe (MIP). The MIP was ejected from the Chandrayaan-1 lunar orbiter and performed remote sensing experiments during its descent to the lunar surface. It impacted near Shackleton crater at the south pole of the lunar surface at 14 November 2008, 20:31 IST.

Chandrayaan-1 was launched on 22 October 2008, 00:52 UTC.^[62]

Chang'e 1 (China)

The Chinese lunar orbiter Chang'e 1, executed a controlled crash onto the surface of the Moon on 1 March 2009, 20:44 GMT, after a 16-month mission. Chang'e 1 was launched on 24 October 2007, 10:05 UTC.^[63]

SELENE (Japan)

SELENE or Kaguya after successfully orbiting the Moon for a year and eight months, the main orbiter was instructed to impact on the lunar surface near the crater Gill at 18:25 UTC on 10 June 2009.^[64] SELENE or Kaguya was launched on 14 September 2007.

LCROSS (U.S.)

The LCROSS data collecting shepherding spacecraft was launched together with the Lunar Reconnaissance Orbiter (LRO) on 18 June 2009 on board an Atlas V rocket with a Centaur upper stage. On 9 October 2009, at 11:31 UTC, the Centaur upper stage impacted the lunar surface, releasing the kinetic energy equivalent of detonating approximately 2 tons of TNT (8.86 GJ).^[65] Six minutes later at 11:37 UTC, the LCROSS shepherding spacecraft also impacted the surface.^[66]

GRAIL (U.S.)

The GRAIL mission consisted of two small spacecraft: GRAIL A (Ebb), and GRAIL B (Flow). They were launched on 10 September 2011 on board a Delta II rocket. GRAIL A separated from the rocket about nine minutes after launch, and GRAIL B followed about eight minutes later.^[67][68] The first probe entered orbit on 31 December 2011 and the second followed on 1 January 2012.^[69] The two spacecraft impacted the Lunar surface on 17 December 2012.^[70]

LADEE (U.S.)

LADEE was launched on 7 September 2013.^[71] The mission ended on 18 April 2014, when the spacecraft's controllers intentionally crashed LADEE into the far side of the Moon,^[72][73] which, later, was determined to be near the eastern rim of Sundman V crater.^[74][75]

Manfred Memorial Moon Mission (Luxemburg)

The Manfred Memorial Moon Mission was launched on 23 October 2014. It conducted a lunar flyby and operated for 19 days which was four times longer than expected. The Manfred Memorial Moon Mission remained attached to the upper stage of its launch vehicle (CZ-3C/E). The spacecraft along with its upper stage impacted the Moon on 4 March 2022.^[76][77][78]

Chang'e 3 (China)

On 14 December 2013 at 13:12 UTC,^[79] Chang'e 3 soft-landed a rover on the Moon. This was China's first soft landing on another celestial body and world's first lunar soft landing since Luna 24 on 22 August 1976.^[80] The mission was launched on 1 December 2013. After successful landing, the lander release the Yutu rover, which moved 114 meters before being immobilized due to system malfunction. But the rover was still operational until July 2016.^[81]

Chang'e 4 (China)

On 3 January 2019 at 2:26 UTC, Chang'e 4 became the first spacecraft to land on the far side of the Moon.^[82] Chang'e 4 was originally designed as the backup of Chang'e 3. It was later adjusted as a mission to the far side of the Moon after the success of Chang'e 3.^[83] After making a successful landing within Von Kármán crater, the Chang'e 4 lander deployed the 140-kilogram (310 lb) Yutu-2 rover and began human's very first close exploration of the far side of the Moon. Because the Moon blocks the communications between far side and Earth, a relay satellite, Queqiao, was launched to the Earth–Moon L2 Lagrangian point a few months prior to the landing to enable communications.

Yutu-2, the second lunar rover from China, was equipped with panoramic camera, lunar penetrating radar, visible and near-infrared Imaging spectrometer and advanced small analyzer for neutrals. As of July 2022, it has survived more than 1000 days on the lunar surface and is still driving with cumulative travel distance of over 1200 meters.^[84][85]

Beresheet (Israel/SpaceIL)

On 22 February 2019, Israeli private space agency SpaceIL launched their spacecraft Beresheet on a Falcon 9 from Cape Canaveral, Florida with the intention of achieving a soft landing. SpaceIL lost contact with the spacecraft during final descent on 11 April 2019, and it crashed as a result of a main engine failure.

The mission was the first Israeli, and the first privately funded, lunar landing attempt.^[86] Despite the failure, the mission represents the closest a private entity has come to a soft lunar landing.^[87]

SpaceIL was originally conceived in 2011 as a venture to pursue the Google Lunar X Prize. The Beresheet lunar lander's target landing destination was within Mare Serenitatis, a vast volcanic basin on the Moon's northern near side.

Chandrayaan-2 (India)

ISRO, the Indian National Space agency, launched Chandrayaan-2 on 22 July 2019.^[88][89] It had three major modules: orbiter, lander and rover. Each of these modules had scientific instruments from scientific research institutes in India and the US.^[90] On 7 September 2019 contact was lost with the Vikram lander at an altitude of 2.1 km (1.3 mi) after a rough braking phase.^[91] Vikram was later confirmed to have crashed and been destroyed.

Chang'e 5 (China)

On 6 December 2020 at 21:42 UTC, Chang'e 5 landed and collected the first lunar soil samples in over 40 years, and then returned the samples to Earth. The 8.2t stack consisting of lander, ascender, orbiter and returner was launched to lunar orbit by a Long March 5 rocket on 24 November. The lander-ascender combination was separated with the orbiter and returner before landing near Mons Rümker in Oceanus Procellarum. The ascender was later launched back to lunar orbit, carrying samples collected by the lander, and completed the first-ever robotic rendezvous and docking in lunar orbit.^[92][93] The sample container was then transferred to the returner, which successfully landed on Inner Mongolia on 16 December 2020, completing China's first extraterrestrial sample return mission.^[94]

Luna 25 (Russia)

In Russia's first attempt to reach the Moon since 1976, and since the dissolution of the Soviet Union, the Luna 25 spacecraft failed during "pre-landing" maneuvers, and crashed into the lunar surface on 19 August 2023.^[95]

Chandrayaan-3 (India)

India's national space agency ISRO launched Chandrayaan-3 on 14 July 2023. Chandrayaan-3 consists of an Indigenous Lander Module (LM), Propulsion module (PM) and the Pragyan rover. The lander with the rover successfully landed near the lunar south pole at 18:04 IST on 23 August 2023.^[96][97]

Smart Lander for Investigating Moon (Japan)

JAXA launched the Smart Lander for Investigating Moon (SLIM) mission on 6 September 2023 at 23:42 UTC (7 September 08:42 Japan Standard Time). It landed on 19 January 2024 at 15:20 UTC, making Japan the fifth country to soft-land on the Moon.^[98] Solar panel orientation issues and possible landing damage complicated the spacecraft's operation.^{[99][100][101]} The mission also deployed two rovers which operated successfully and independently communicated with Earth.^[100]

Intuitive Machines-1 Odysseus lander (U.S.)

On 22 February 2024, Intuitive Machine's Odysseus successfully landed on the Moon after taking off on a SpaceX Falcon 9 liftoff on 15 February 2024 in a mission between NASA, SpaceX, and Intuitive Machines, marking the United States' first soft unmanned Moon landing in over 50 years. This mission also marks the first privately owned spacecraft to land on the Moon and the first landing with cryogenic propellants.^[102][103] Though it landed successfully, one of the lander's legs broke upon landing and it tilted up on the other side, 18°, due to landing on a slope, but the lander survived and payloads are functioning as expected.^[104] EagleCam was not ejected prior to landing. It was later ejected on 28 February but was partially a failure as it returned all types of data except post-IM-1 landing images that were the main aim of its mission.^[105]