Surveyor 2 was to be the second lunar lander in the uncrewed

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, p ...

Surveyor program The Surveyor program was a NASA program that, from June 1966 through January 1968, sent seven robotic spacecraft to the surface of the Moon. Its primary goal was to demonstrate the feasibility of Soft landing (rocketry), soft landings on the Moo ...

to explore the

Moon The Moon is Earth's only natural satellite. It Orbit of the Moon, orbits around Earth at Lunar distance, an average distance of (; about 30 times Earth diameter, Earth's diameter). The Moon rotation, rotates, with a rotation period (lunar ...

. After launch on September 20, 1966, a mid-course correction failure resulted in the spacecraft losing control. Contact was lost with the spacecraft at 9:35 UTC, September 22.

Background

On February 3, 1966, the

Luna 9 Luna 9 (Луна-9), internal designation Ye-6 No.13, was an uncrewed space mission of the Soviet Union's Luna programme. On 3 February 1966, the Luna 9 spacecraft became the first spacecraft to achieve a soft landing on the Moon and return ima ...

spacecraft was the first spacecraft to achieve a

lunar Lunar most commonly means "of or relating to the Moon". Lunar may also refer to: Arts and entertainment * ''Lunar'' (series), a series of video games * "Lunar" (song), by David Guetta * "Lunar", a song by Priestess from the 2009 album ''Prior t ...

soft landing A soft landing is any type of aircraft, rocket or spacecraft landing that does not result in significant damage to or destruction of the vehicle or its payload, as opposed to a hard landing. The average vertical speed in a soft landing should b ...

and to transmit photographic data to

Earth Earth is the third planet from the Sun and the only astronomical object known to Planetary habitability, harbor life. This is enabled by Earth being an ocean world, the only one in the Solar System sustaining liquid surface water. Almost all ...

. On May 30,

Surveyor 1 Surveyor 1 was the first lunar soft-lander in the uncrewed Surveyor program of the National Aeronautics and Space Administration (NASA, United States). This lunar soft-lander gathered data about the lunar surface that would be needed for the c ...

launched, landing on

Oceanus Procellarum Oceanus Procellarum ( ; from ) is a vast lunar mare on the western edge of the near side of the Moon. It is the only one of the lunar maria to be called an "Oceanus" (ocean), due to its size: Oceanus Procellarum is the largest of the maria ("s ...

on June 2. This craft also transmitted photographic data back to Earth. This spacecraft was the second of a series designed to achieve a soft landing on the Moon and to return lunar surface photography for determining characteristics of the lunar terrain for

Apollo program The Apollo program, also known as Project Apollo, was the United States human spaceflight program led by NASA, which Moon landing, landed the first humans on the Moon in 1969. Apollo followed Project Mercury that put the first Americans in sp ...

lunar landing missions. Besides transmitting photos, Surveyor 2 was planned to perform a 'bounce', to photograph underneath its own landing site. It was also equipped to return data on radar reflectivity of the lunar surface, bearing strength of the lunar surface, and spacecraft temperatures for use in the analysis of lunar surface temperatures.

Launch

The launch took place from Space Launch Complex 36A at Cape Kennedy, Florida aboard an

Atlas-Centaur The Atlas-Centaur was a United States expendable launch vehicle derived from the SM-65 Atlas D missile. The vehicle featured a Centaur (rocket stage), Centaur upper stage, the first such stage to use high-performance liquid hydrogen as fuel. La ...

rocket. Liftoff was at 12:32 UTC on 20 September 1966.

Failure

The target area proposed was within

Sinus Medii Sinus Medii (Latin ''sinus mediī'' "Middle Bay") is a small lunar mare. It takes its name from its location at the intersection of the Moon's equator and prime meridian; as seen from the Earth, this feature is located in the central part of the ...

. The Atlas-Centaur had placed Surveyor 2 on a path to the Moon that was only 130 km from its aim point. During the midcourse correction maneuver one

vernier thruster A vernier thruster is a rocket engine used on a spacecraft or launch vehicle for fine adjustments to the attitude or velocity. Depending on the design of a craft's maneuvering and stability systems, it may simply be a smaller thruster complement ...

failed to ignite, resulting in unbalanced thrust that caused the spacecraft to tumble for its remaining 54 hours. Attempts to salvage the mission failed. Contact was lost with the spacecraft at 9:35 UTC, September 22. The spacecraft was targeted at Sinus Medii, but crashed near Copernicus crater. The spacecraft was calculated to have impacted the lunar surface at 03:18 UTC, September 23, 1966. Its weight on impact was 644 lb (292 kg), and speed was about 6000 miles an hour (2.6 km/s = 5840 mph), slightly over lunar escape velocity (2.4 km/s) and similar to the impact velocities of the

Ranger program The Ranger program was a series of uncrewed space missions by the United States in the 1960s whose objective was to obtain the first close-up images of the surface of the Moon. The Ranger spacecraft were designed to take images of the lunar su ...

spacecraft.

Aftermath

Lunar exploration continued to be challenging. The next Soviet mission, Cosmos 111, was launched on March 1, 1966, but failed to reach a proper lunar trajectory, re-entering Earth's atmosphere two days later.

Surveyor 3 Surveyor 3 is the third lander of the American uncrewed Surveyor program sent to explore the surface of the Moon in 1967 and the second to successfully land. It was the first mission to carry a surface-soil sampling-scoop. Surveyor 3 was vis ...

soft-landed on April 20, 1967, at the

Mare Cognitum Mare Cognitum (Latin ''cognitum'', the "Sea that has Become Known") is a lunar mare located in a basin or large Impact crater, crater which sits in the second ring of Oceanus Procellarum. To the northwest of the mare is the Montes Riphaeus mounta ...

portion of the Oceanus Procellarum. It transmitted a total of 6,315 television images to the Earth. There were seven Surveyor missions; five were successful. Surveyors 2 and 4 failed. Each consisted of a single uncrewed spacecraft designed and built by

Hughes Aircraft Company The Hughes Aircraft Company was a major American aerospace and defense contractor founded on February 14, 1934 by Howard Hughes in Glendale, California, as a division of the Hughes Tool Company. The company produced the Hughes H-4 Hercules air ...

. The precise location of the Surveyor 2 crash site is unknown.

Centaur upper stage

The

Centaur A centaur ( ; ; ), occasionally hippocentaur, also called Ixionidae (), is a creature from Greek mythology with the upper body of a human and the lower body and legs of a horse that was said to live in the mountains of Thessaly. In one version o ...

upper stage of the rocket used to launch Surveyor continued on its original trajectory past the Moon, placing it into a solar orbit similar to that of the Earth. The Centaur was untracked from that point forward. In August 2020, NASA announced the sighting of an object in a solar orbit which could shortly make a close pass with the Earth. On September 23, 2020, NASA announced that this was likely the lost Centaur booster, and likely to be re-captured into Earth orbit. This would be the second time that a rocket upper stage has done so, after the upper stage of a Saturn V rocket from the

Apollo 12 Apollo 12 (November 14–24, 1969) 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 in Florida. Commander Charles ...

launch re-entered Earth orbit in 2002. In December 2020, NASA confirmed that it was the lost Centaur stage.

References

External links

*Labeled

Lunar Orbiter 4 Lunar Orbiter 4 was a robotic U.S. spacecraft, part of the Lunar Orbiter program, Lunar Orbiter Program, designed to orbit the Moon, after the three previous orbiters had completed the required needs for Project Apollo, Apollo mapping and site s ...

photograph showing the Surveyor 2 crash site
IV-114-H1

Surveyor 2 flight performance Final report - Jan 1967 (PDF)Surveyor Program Results (PDF) 1969
{{Use American English, date=January 2014 2 Spacecraft launched in 1966 Missions to the Moon Spacecraft launched by Atlas-Centaur rockets Spacecraft that impacted the Moon 1966 on the Moon