Surveyor 1 was the first lunar soft-lander in the uncrewed Surveyor program of the

National Aeronautics and Space Administration The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding ...

(NASA,

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). This

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-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 Oceanus Procellarum ( la, Ōceanus procellārum, lit=Ocean of Storms) 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 Proc ...

'' was the first by an American

space probe A space probe is an artificial satellite that travels through space to collect scientific data. A space probe may orbit Earth; approach the Moon; travel through interplanetary space; flyby, orbit, or land or fly on other planetary bodies; o ...

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. Surveyor 1 was launched May 30, 1966, from the

Cape Canaveral Air Force Station Cape Canaveral Space Force Station (CCSFS) is an installation of the United States Space Force's Space Launch Delta 45, located on Cape Canaveral in Brevard County, Florida. Headquartered at the nearby Patrick Space Force Base, the statio ...

at Cape Canaveral, Florida, and it landed on the Moon on June 2, 1966. Surveyor 1 transmitted 11,237 still photos of the lunar surface to the Earth by using a television camera and a sophisticated

radio Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a tr ...

telemetry Telemetry is the in situ collection of measurements or other data at remote points and their automatic transmission to receiving equipment (telecommunication) for monitoring. The word is derived from the Greek roots ''tele'', "remote", an ...

system. The Surveyor program was managed by the

Jet Propulsion Laboratory The Jet Propulsion Laboratory (JPL) is a Federally funded research and development centers, federally funded research and development center and NASA field center in the City of La Cañada Flintridge, California, La Cañada Flintridge, California ...

, in

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, and the Surveyor space probe was built by the

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 Hughes Tool Company. The company was known for producing, among other ...

El Segundo, California El Segundo ( , ; ) is a city in Los Angeles County, California, United States. Located on Santa Monica Bay, it was incorporated on January 18, 1917, and is part of the South Bay Cities Council of Governments. The population was 16,731 as of the ...

Mission description

The Surveyor series of

s was designed to carry out the first soft landings on the Moon by any American

spacecraft A spacecraft is a vehicle or machine designed to fly in outer space. A type of artificial satellite, spacecraft are used for a variety of purposes, including communications, Earth observation, meteorology, navigation, space colonization, ...

. No instrumentation was carried specifically for scientific experiments by Surveyor 1, but considerable scientific data were collected by its

television camera A professional video camera (often called a television camera even though its use has spread beyond television) is a high-end device for creating electronic moving images (as opposed to a movie camera, that earlier recorded the images on film). ...

and then returned to Earth via the Deep Space Network from 1966 to 1967. These spacecraft carried two television cameras — one for its approach, which was not used in this case, and one for taking still pictures of the lunar surface. Over 100 engineering sensors were on board each Surveyor. Their television systems transmitted pictures of the spacecraft footpad and surrounding lunar terrain and surface materials. These spacecraft also acquired data on the radar reflectivity of the lunar surface, the load-bearing strength of the

lunar surface The geology of the Moon (sometimes called selenology, although the latter term can refer more generally to " lunar science") is quite different from that of Earth. The Moon lacks a true atmosphere, which eliminates erosion due to weather. It does ...

, and the temperatures for use in the analysis of the lunar surface temperatures. (Later Surveyor space probes, beginning with Surveyor 3, carried scientific instruments to measure the composition and

mechanical properties A materials property is an intensive property of a material, i.e., a physical property that does not depend on the amount of the material. These quantitative properties may be used as a metric by which the benefits of one material versus another ...

of the lunar "soil".) Surveyor 1 was launched May 30, 1966 and sent directly into a trajectory to the Moon without any parking orbit. Its retrorockets were turned off at a height of about 3.4 meters above the lunar surface. Surveyor 1 fell freely to the surface from this height, and it landed on the lunar surface on June 2, 1966, on the ''Oceanus Procellarum''. This location was at . This is within the northeast portion of the large crater called Flamsteed P (or the ''Flamsteed Ring'').

Flamsteed John Flamsteed (19 August 1646 – 31 December 1719) was an English astronomer and the first Astronomer Royal. His main achievements were the preparation of a 3,000-star catalogue, ''Catalogus Britannicus'', and a star atlas called ''Atlas Coe ...

itself lies within Flamsteed P on the south side. The duration of the

spaceflight Spaceflight (or space flight) is an application of astronautics to fly spacecraft into or through outer space, either with or without humans on board. Most spaceflight is uncrewed and conducted mainly with spacecraft such as satellites in ...

of Surveyor 1 was about 63 hours, 30 minutes. Surveyor 1's lunar launch weight was about , and its landing weight (minus expended maneuvering propellant, its solid-fueled retrorocket (which had been jettisoned), and its

radar altimeter A radar altimeter (RA), also called a radio altimeter (RALT), electronic altimeter, reflection altimeter, or low-range radio altimeter (LRRA), measures altitude above the terrain presently beneath an aircraft or spacecraft by timing how long it t ...

system) was about . Surveyor 1 transmitted

video Video is an electronic medium for the recording, copying, playback, broadcasting, and display of moving visual media. Video was first developed for mechanical television systems, which were quickly replaced by cathode-ray tube (CRT) sy ...

data from the Moon beginning shortly after its landing through July 14, 1966, but with a period of no operations during the two-week long lunar night of June 14, 1966 through July 7, 1966. Because the Moon always presents the same face to Earth, "line-of-sight"

radio communication Radio is the technology of signaling and communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and 300 gigahertz (GHz). They are generated by an electronic device called a trans ...

s with Surveyor 1 required only changes in ground stations as the Earth rotated. However, since it was solar-powered, Surveyor 1 had no electricity with which to function during the two weeks of the lunar nights. The return of engineering information (temperatures, etc.) from Surveyor 1 continued through January 7, 1967, with several interruptions during the lunar nights. The landing of Surveyor 1 was carried live on some television networks, and the success of the first Surveyor landing was considered surprising, especially after the failure of a number of the Ranger spacecraft en route to the Moon. Justin Rennilson, formerly of

, stated, "We figured the probability of success at around 10 to 15 percent." Among hundreds of other challenges, an uninterrupted communication link for navigation and control was critical to success.

Science instruments

Television

The TV camera consisted of a

vidicon Video camera tubes were devices based on the cathode ray tube that were used in television cameras to capture television images, prior to the introduction of charge-coupled device (CCD) image sensors in the 1980s. Several different types of tubes ...

tube, a zoom lens operated at either end of its range resulting in 25 millimeter and 100 millimeter focal-lengths, resulting in optical fields of view of 25.3 or 6.43 degrees, a shutter, several optical filters, and iris-system mounted along an axis inclined approximately 16 degrees from the central axis of Surveyor 1. The camera was mounted under a mirror that could be moved in azimuth and elevation. The rotation of the mirror in the azimuth direction, while providing azimuth coverage capability results in an image rotation proportional to the angular azimuth position of the mirror. This is because the image plane and scanning raster of the vidicon are stationary with respect to the mirror azimuth axis. The mirror drive mechanism consisting of stepper motors provided a step size of 2.48° ±0.1° in elevation and 3.0° ±0.1° in azimuth. This calibrated stepping reference allowed the creation of large composite mosaics of the lunar surface and using the data read-back from the iris and focus positioning of the lens permitted some photogrammetric measurements of various lunar features.Montgomery, Wolf ''The Surveyor lunar landing television system''. IEEE Spectrum, August 1966, p. 55-56 The TV camera's operation was dependent on the receipt of the proper radio commands from the Earth. Frame-by-frame coverage of the lunar surface was obtained over 360 degrees in azimuth and from +40 degrees above the plane normal to the camera's axis to -65 degrees below this plane. Both 600-line and 200-line modes of operation were used. The 200-line mode transmitted over an omnidirectional antenna for the first 14 photos and scanned one frame every 61.8 seconds. The remaining transmissions were of 600-line pictures over a directional antenna, and each frame was scanned every 3.6 seconds. Each 200-line picture required 20 seconds for a complete video transmission and it used a radio bandwidth of about 1.2

kilohertz The hertz (symbol: Hz) is the unit of frequency in the International System of Units (SI), equivalent to one event (or cycle) per second. The hertz is an SI derived unit whose expression in terms of SI base units is s−1, meaning that on ...

. Each 600-line picture required about one second to be read from the vidicon tube, and they required a radio bandwidth of about 220 kilohertz. The data transmissions were converted into a standard TV signal for both

closed-circuit TV Closed-circuit television (CCTV), also known as video surveillance, is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors. It differs from broadcast television in that the signal is not openly tr ...

and

broadcast TV Broadcast television systems (or terrestrial television systems outside the US and Canada) are the encoding or formatting systems for the transmission and reception of terrestrial television signals. Analog television systems were standardized by ...

. The television images were displayed on Earth on a slow-scan monitor coated with a long persistency phosphor. The persistency was selected to optimally match the nominal maximum frame rate. One frame of TV identification was received for each incoming TV frame, and it was displayed in real time at a rate compatible with the incoming image. These data were recorded on a video magnetic tape recorder. Over 10,000 pictures were taken by Surveyor 1's TV camera before the lunar sunset of June 14, 1966. Included in these pictures were wide-angle and narrow-angle panoramas, focus ranging surveys, photometric surveys, special area surveys, and celestial photography. Surveyor 1 responded to commands to activate the camera on July 7, and by July 14, 1966, it had returned nearly 1000 more pictures. File:Surveyor 1 shadow lunarsurface.jpg, Surveyor 1's shadow against the lunar surface (upside-down image) File:Surveyor 1 Fig 7-41a1.jpg, The mare surface File:Surveyor 1 Fig 7-41a2.jpg, Another view of the mare surface File:Surveyor 1 Fig 3-36a.jpg, Irregularly shaped crater at the landing site File:Surveyor 1 Fig 3-56.jpg, Mottled rock about 50 cm long near Surveyor 1

Strain gauge

Strain gauges were mounted on each leg shock absorber to record the peak axial forces at landing impact of the spacecraft. They were designed to accept a force of approximately 800 kgf (7.8 kN).

Legacy and Status

On January 6, 1967, Surveyor 1 was reactivated for 12 hours. The spacecraft returned data on the motion of the Moon, which would be used to refine the map of its orbital path around the Earth as well as better determine the distance between the two worlds.

References

External links

Surveyor 1 digitized panorama with color photometric target
from Surveyor Digitization Project *
Panoramas of the Surveyor 1 landing site
from The International Atlas of Lunar Exploration by Philip J. Stooke
Surveyor Program Results (PDF) 1969

Surveyor I – A Preliminary Report – June 1, 1966 (PDF)

Surveyor I mission report. Part II – Scientific data and results – Sep 1966 (PDF)

Details of Surveyor 1 launch, and also more on the Surveyor program

Surveyor I images
at Lunar and Planetary Institute
Surveyor Site 1 Lunar Map
at Lunar and Planetary Institute
Surveyor Site 1 Lunar PhotoMap
at Lunar and Planetary Institute
Lunar Orbiter 1 photo 192
showing the northeastern part of Flamsteed P crater, where Surveyor 1 landed {{Use American English, date=January 2014 1 Spacecraft launched in 1966 Missions to the Moon Spacecraft launched by Atlas-Centaur rockets Soft landings on the Moon Derelict landers (spacecraft) 1966 on the Moon