Retroreflector
A retroreflector (sometimes called a retroflector or cataphote) is a device or surface that reflection (physics), reflects radiation (usually light) back to its source with minimum scattering. This works at a wide range of angle of incidence (opt ...
s are devices which reflect light back to its source. Five were left at five sites on the
Moon
The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...
by three crews of the
Apollo program and two remote landers of the
Lunokhod program
Lunokhod ( rus, Луноход, p=lʊnɐˈxot, "Moonwalker") was a series of Soviet robotic lunar rovers designed to land on the Moon between 1969 and 1977. Lunokhod 1 was the first roving remote-controlled robot to land on an extraterrestrial ...
.
[Lunar Retroreflectors](_blank)
/ref> Lunar reflectors have enabled precise measurement of the Earth–Moon distance since 1969 using lunar laser ranging.[Slava G. Turyshev: ]
From Quantum to Cosmos: Fundamental Physics Research in Space
' (2009) - Page 300
Successfully placed reflectors
Attempted and planned reflectors
Gallery
Image:Apollo 11 Lunar Laser Ranging Experiment.jpg, Apollo 11
Apollo 11 (July 16–24, 1969) was the American spaceflight that first landed humans on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin landed the Apollo Lunar Module ''Eagle'' on July 20, 1969, at 20:17 UTC, ...
Lunar Laser Ranging Retroreflector
Image:ALSEP AS14-67-9386.jpg, Apollo 14 retroreflector
Image:ALSEP_AS15-85-11468.jpg, Close-up of Apollo 15 retroreflector
Image:Lunokhod-2 model.jpg, Model of Lunokhod 2
''Lunokhod 2'' (russian: Луноход-2 ("Moonwalker 2"), also known as Аппарат 8ЕЛ № 204 ("Device 8EL No. 204")) was the second of two unmanned lunar rovers that landed on the Moon by the Soviet Union as part of the Lunokhod pro ...
retroreflector (hexagon in front)
See also
* Lunar laser ranging
* List of artificial objects on the Moon
This is a partial list of artificial materials left on the Moon, many during the missions of the Apollo program. The table below does not include lesser Apollo mission artificial objects, such as a hammer and other tools, List of retroreflectors o ...
* List of missions to the Moon
As part of human exploration of the Moon, numerous space missions have been undertaken to study Earth's natural satellite. Of the Moon landings, Luna 2 of the Soviet Union was the first spacecraft to reach its surface successfully, intentionall ...
References
{{DEFAULTSORT:Retroreflectors on the Moon
Lunar science
Space lists