Mission type | Lunar lander |
---|---|
Operator | NASA |
COSPAR ID | 1967-035A |
SATCAT no. | 02756 |
Mission duration | 16 days (launch to last contact) |
Spacecraft properties | |
Manufacturer | Hughes Aircraft |
Launch mass | 2,262 lb (1,026 kg) [1] |
Landing mass | 653 lb (296 kg) |
Start of mission | |
Launch date | April 17, 1967, 07:05:01 UTC [1] |
Rocket | Atlas LV-3C Centaur-D AC-12 |
Launch site | Cape Canaveral, LC‑36B |
End of mission | |
Last contact | May 3, 1967 |
Lunar lander | |
Landing date | April 20, 1967, 00:04:53 UTC |
Landing site | 3°00′58″S23°25′04″W / 3.01612°S 23.41791°W |
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 visited by Apollo 12 astronauts Pete Conrad and Alan Bean in November 1969, and remains the only probe visited by humans on another world. The Apollo 12 astronauts excised several components of Surveyor 3, including the television camera, and returned them to Earth for study.
Launched on April 17, 1967, Surveyor 3 landed on April 20, 1967, at the Mare Cognitum portion of the Oceanus Procellarum (S3° 01' 41.43" W23° 27' 29.55"), in a small crater that was subsequently named Surveyor. It transmitted 6,315 TV images to the Earth, including the first images to show what planet Earth looked like from the Moon's surface. [2]
As Surveyor 3 was landing in the crater [3] [4] highly reflective rocks confused the spacecraft's lunar descent radar. The engines failed to cut off at 14 feet (4.3 meters) in altitude as called for in the mission plans, and this delay caused the lander to bounce on the lunar surface twice. [5] Its first bounce reached the altitude of about 35 feet (11 meters). The second bounce reached a height of about 11 feet (3.4 meters). On the third impact with the surface – from the initial altitude of 10 feet (3 meters), and velocity of zero, which was below the planned altitude of 14 feet (4.3 meters), and very slowly descending – Surveyor 3 settled down to a soft landing as intended.
This Surveyor mission was the first that carried a surface-soil sampling-scoop, which can be seen on its extendable arm in the pictures. This mechanism was mounted on an electric-motor-driven arm and was used to dig four trenches in the lunar soil. These trenches were up to 7 inches (18 cm) deep. Samples of soil from the trenches were placed in front of the Surveyor's television cameras to be photographed and the pictures radioed back to the Earth. When the first lunar nightfall came on May 3, 1967, Surveyor 3 was shut down because its solar panels were no longer producing electricity. At the next lunar dawn (after 14 terrestrial days, or about 336 hours), Surveyor 3 could not be reactivated, because of the extremely cold temperatures that it had experienced. This is in contrast with the Surveyor 1, which was able to be reactivated twice after lunar nights, but then never again. [6]
Surveyor 3 became famous after the crew of Apollo 12 used it as a landing target site. Landing within walking distance on November 19, 1969, the astronauts took several pictures of the probe and removed a scoop from the probe's soil mechanics-surface sampler, a section of unpainted aluminum tube from a strut supporting the Surveyor's radar altimeter and Doppler velocity sensor, another section of aluminum tube that was coated with inorganic white paint and a segment of television cable wrapped in aluminized plastic film and the Surveyor 3's television camera which were returned to Earth. [7] Surveyor 3 is the only probe visited by humans on another world.
The television camera on Surveyor 3 consisted of a vidicon tube, two 25 and 100 millimeter focal length lenses, shutters, clear, red, green and blue optical filters, [8] and an iris mounted along an axis inclined about 16 degrees to the central axis of the spacecraft. The TV camera was mounted under a mirror that could be moved in azimuth (horizontally) and elevation (vertically). The operation of the camera was completely dependent upon the receipt of proper commands from the Earth. Frame-by-frame coverage of the lunar surface was obtained over the complete 360 degrees in azimuth, and from +40 degrees above the plane normal to the camera's Z-axis to −65 degrees below this plane. Both 600-line and 200-line modes of TV camera operation were used. The 200-line mode transmitted over an omnidirectional antenna and scanned one frame every 61.8 seconds. A complete video transmission of each 200-line picture required 20 seconds and used a bandwidth of 1.2 kHz. The 600-line pictures were transmitted over a directional antenna. These pictures were scanned as often as once every 3.6 seconds. Each 600-line picture required a nominal one second to be read from the image vidicon, and its transmission required a 220 kHz bandwidth, using digital picture transmission. The TV photos were displayed back on the Earth on a slow-scan TV monitor that was coated with a long-persistence phosphor. Its persistence had been selected to match the nominal maximum frame rate. One frame of TV identification was received for each incoming TV photo, and the picture was displayed in real-time at a rate compatible with that of the incoming image. These data were recorded on a video magnetic-tape recorder. The camera returned 6315 pictures between April 20 and May 3, 1967, including views of the spacecraft itself, panoramic lunar surveys, views of the mechanical surface digger at work, and of an April 24 eclipse of the Sun by the Earth. [9]
The Apollo 12 Lunar Module landed near Surveyor 3 on November 19, 1969. Astronauts Conrad and Bean examined the spacecraft, and they brought back about 22 pounds (10 kg) of parts of the Surveyor to the Earth, including its TV camera, which is now on permanent display in the National Air and Space Museum in Washington, D.C.
Analysis of the camera found that it withstood 947 days in the vacuum of space, including 32 two-week lunar nights with temperatures dropping below −200 °F (−130 °C), in good condition. Most major components were functional and undamaged. Some changes were caused by temperature extremes, micrometeorite strikes, and manufacturing errors. [10]
The soil mechanics surface sampler was designed to dig, scrape, and trench the lunar surface and to transport lunar surface material while being photographed so that the properties of the lunar surface could be determined. The sampler was mounted below the television camera and consisted primarily of a scoop approximately 4.7 inches (120 mm) long and 2.0 inches (50 mm) wide. The scoop consisted of a container, a sharpened blade, and an electric motor to open and close the container. A small footpad was attached to the scoop door to present a flat surface to the lunar surface. The scoop was capable of holding a maximum quantity of approximately 1.3 inches (32 mm) diameter of solid lunar material and a maximum of 6.1 cubic inches (100 cm3) of granular material. The scoop was mounted on a pantograph arm that could be extended about 5 feet (1.5 m) or retracted close to the spacecraft motor drive. The arm could also be moved from an azimuth of +40 to -72 degrees or be elevated 5.1 inches (130 mm) by motor drives. It could also be dropped onto the lunar surface under force provided by gravity and a spring. The surface sampler performed seven bearing tests, four trench tests, and thirteen impact tests. The total operating time was 18 hours, 22 minutes on ten separate occasions. Measurements of motor currents and forces applied to the surface were not obtained due to the state of the spacecraft telemetry following landing on the lunar surface. However, estimations were possible. The small spring constant of the torque spring precluded the determination of density from the impact tests. Penetrations of 1.5 to 2.0 in (38 to 50 mm) were obtained from the bearing tests, and a 6.9 in (175 mm) depth was reached during trenching operations. The design of the mechanism and its electronic auxiliary was more than adequate for the lunar surface operations.[ citation needed ] The scoop was also returned to Earth by the Apollo 12 astronauts and is currently on display at JPL.
The Surveyor 3 landing site was later selected also as the landing target for the Lunar Module of the Apollo 12 crewed lunar mission in 1969. Several components of the Surveyor 3 lander were collected and returned to the Earth for study of the long-term exposure effects of the harsh lunar environment on human-made objects and materials. Although space probes have returned to Earth in the decades since Apollo 12, this remains the only occasion on which humans have visited a probe that had been sent off-world. [11]
It is widely claimed that a common type of bacterium, Streptococcus mitis , accidentally contaminated the Surveyor's camera prior to launch, and that the bacteria survived dormant in the harsh lunar environment for two and a half years, supposedly then to be detected when Apollo 12 brought the Surveyor's camera back to the Earth. [12] This claim has been cited by some as providing credence to the idea of interplanetary panspermia, but more importantly, it led NASA to adopt strict abiotic procedures for space probes to prevent contamination of the planet Mars and other astronomical bodies that are suspected of having conditions possibly suitable for life. Most dramatically, the Galileo space probe was deliberately destroyed at the end of its mission by crashing it into Jupiter, to avoid the possibility of contaminating the Jovian moon Europa with bacteria from Earth. The Cassini probe also impacted Saturn at the end of its mission in 2017.
However, independent investigators have challenged the claim of surviving bacteria on Surveyor 3 on the Moon. There is a possibility the contamination was caused by using a non-airtight container, [13] or when the samples were being taken in the clean room after Apollo 12. [13] [14]
In 2009, the Lunar Reconnaissance Orbiter (LRO) photographed the Surveyor 3 landing site in some detail, in which surrounding astronaut foot tracks could also be seen. [15] In 2011, the LRO returned to the landing site at a lower altitude to take higher resolution photographs. [16]
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 in 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 14 was the eighth crewed mission in the United States Apollo program, the third to land on the Moon, and the first to land in the lunar highlands. It was the last of the "H missions", landings at specific sites of scientific interest on the Moon for two-day stays with two lunar extravehicular activities.
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 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 landings on the Moon. The Surveyor craft were the first American spacecraft to achieve soft landing on an extraterrestrial body. The missions called for the craft to travel directly to the Moon on an impact trajectory, a journey that lasted 63 to 65 hours, and ended with a deceleration of just over three minutes to a soft landing.
Surveyor 7 was sent to the Moon in 1968 on a scientific and photographic mission as the seventh and last lunar lander of the American uncrewed Surveyor program. With two previous unsuccessful missions in the Surveyor series, and with Surveyor 7's landing success, Surveyor 7 became the fifth and final spacecraft in the series to achieve a lunar soft landing. A total of 21,091 pictures were transmitted from Surveyor 7 back to Earth.
Surveyor 1 was the first lunar soft-lander in the uncrewed Surveyor program of the National Aeronautics and Space Administration. This lunar soft-lander gathered data about the lunar surface that would be needed for the crewed Apollo Moon landings that began in 1969. The successful soft landing of Surveyor 1 on the Ocean of Storms was the first by an American space probe on any extraterrestrial body, occurring on the first attempt and just four months after the first soft Moon landing by the Soviet Union's Luna 9 probe.
Luna 21 was an uncrewed space mission, and its spacecraft, of the Luna program, also called Lunik 21, in 1973. The spacecraft landed on the Moon and deployed the second Soviet lunar rover, Lunokhod 2. The primary objectives of the mission were to collect images of the lunar surface, examine ambient light levels to determine the feasibility of astronomical observations from the Moon, perform laser ranging experiments from Earth, observe solar X-rays, measure local magnetic fields, and study mechanical properties of the lunar surface material.
Surveyor 5 is the fifth lunar lander of the American uncrewed Surveyor program sent to explore the surface of the Moon. Surveyor 5 landed on Mare Tranquillitatis in 1967. A total of 19,118 images were transmitted to Earth.
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.
A lander is a spacecraft that descends towards, then comes to rest on the surface of an astronomical body other than Earth. In contrast to an impact probe, which makes a hard landing that damages or destroys the probe upon reaching the surface, a lander makes a soft landing after which the probe remains functional.
Mare Tranquillitatis is a lunar mare that sits within the Tranquillitatis basin on the Moon. It contains Tranquility Base, the first location on another celestial body to be visited by humans.
A Moon landing or lunar landing is the arrival of a spacecraft on the surface of the Moon, including both crewed and robotic missions. The first human-made object to touch the Moon was Luna 2 in 1959.
Apollo 15 lunar surface operations were conducted from July 30 to August 2, 1971, by Apollo 15 Commander David Scott and Apollo Lunar Module Pilot James Irwin, who used the first Lunar Roving Vehicle to make three exploratory trips away from their landing site at the base of the Apennine Mountains, near Hadley Rille.
A lunar lander or Moon lander is a spacecraft designed to land on the surface of the Moon. As of 2024, the Apollo Lunar Module is the only lunar lander to have ever been used in human spaceflight, completing six lunar landings from 1969 to 1972 during the United States' Apollo Program. Several robotic landers have reached the surface, and some have returned samples to Earth.
The physical exploration of the Moon began when Luna 2, a space probe launched by the Soviet Union, made a deliberate impact on the surface of the Moon on September 14, 1959. Prior to that the only available means of lunar exploration had been observations from Earth. The invention of the optical telescope brought about the first leap in the quality of lunar observations. Galileo Galilei is generally credited as the first person to use a telescope for astronomical purposes, having made his own telescope in 1609, the mountains and craters on the lunar surface were among his first observations using it.
Third-party evidence for Apollo Moon landings is evidence, or analysis of evidence, about the Moon landings that does not come from either NASA or the U.S. government, or the Apollo Moon landing hoax theorists. This evidence provides independent confirmation of NASA's account of the six Apollo program Moon missions flown between 1969 and 1972.
The Lunar Reconnaissance Orbiter (LRO) is a NASA robotic spacecraft currently orbiting the Moon in an eccentric polar mapping orbit. Data collected by LRO have been described as essential for planning NASA's future human and robotic missions to the Moon. Its detailed mapping program is identifying safe landing sites, locating potential resources on the Moon, characterizing the radiation environment, and demonstrating new technologies.