David Randolph Scott is a retired test pilot and NASA astronaut, the seventh person to walk on the Moon. The commander of Apollo 15, Scott was selected as an astronaut as part of the third group in 1963. Scott flew three times in space, is the only living commander of an Apollo mission that landed on the Moon and one of four surviving Moon walkers. Before becoming an astronaut, Scott graduated from the United States Military Academy at West Point and joined the Air Force. After serving as a fighter pilot in Europe, he graduated from the Air Force Experimental Test Pilot School and Aerospace Research Pilot School. Scott retired from the Air Force in 1975 with the rank of colonel, more than 5,600 hours of logged flying time; as an astronaut, Scott made his first flight into space as pilot of the Gemini 8 mission, along with Neil Armstrong, in March 1966, spending just under eleven hours in low Earth orbit. Scott spent ten days in orbit in March 1969 as Command Module Pilot aboard Apollo 9, a mission that extensively tested the Apollo spacecraft, along with Commander James McDivitt and Lunar Module Pilot Rusty Schweickart.
After backing up Apollo 12, Scott made his third and final flight into space as commander of the Apollo 15 mission, the fourth manned lunar landing and the first J mission. Scott and James Irwin remained on the Moon for three days. Following the return to Earth and his crewmates fell from favor with NASA after it was disclosed they had carried 400 unauthorized postal covers to the Moon. After serving as director of NASA's Dryden Flight Research Center in California, Scott retired from the agency in 1977. Since he has worked on a number of space-related projects and served as consultant for several films about the space program, including Apollo 13. Scott was born June 1932, at Randolph Field near San Antonio, Texas, his father was Tom William Scott, a fighter pilot in the United States Army Air Corps who would rise to the rank of brigadier general. Scott lived his earliest years at Randolph Field, where his father was stationed, before moving to an air base in Indiana, in 1936 to Manila in the Philippines under U.
S. rule. Although there were servants to aid the family, the Scotts did not have much money, David remembered his father as a strict disciplinarian; the family returned to the United States in December 1939. By the time of Pearl Harbor in 1941, the family was living in San Antonio again; as it was felt that he needed more discipline than he would receive with his father gone for three years, David was sent to Texas Military Institute, spending his summers at Hermosa Beach in California with his father's college friend, David Shattuck, after whom he had been named. Determined to become a pilot like his father, David built many model airplanes and watched with fascination war films about flying. By the time of Tom Scott's return, David was old enough to be allowed to go up in a military aircraft with him, in David Scott's 2006 autobiography remembered it as "the most exciting thing I had experienced". David Scott was active in the Boy Scouts of America, achieving Life Scout. With Tom Scott assigned to March Air Force Base near Riverside, David attended Riverside Polytechnic High School, where he joined the swim team and set several state and local swim records.
Before he could finish there, Tom Scott was transferred to Washington, D. C. and after some discussion as to whether David should remain in California to graduate, David attended Western High School in Washington, graduating in June 1949. David Scott wanted an appointment to the United States Military Academy at West Point, but lacked connections to secure one, he took a government civil service examination for competitive appointments and accepted a swimming scholarship to the University of Michigan where he was an honor student in the Engineering school. In the spring of 1950, he accepted an invitation to attend West Point. Scott still wanted to fly, wanted to be commissioned in the newly-established Air Force. Since the Air Force had as yet no academy, an interim arrangement had been made whereby a quarter of West Point and United States Naval Academy graduates could volunteer to be commissioned as Air Force officers. Earning a Bachelor of Science degree, Scott graduated 5th in his class of 633, was given his first choice of service, the Air Force.
Scott did six months primary pilot training at Marana Air Base in Arizona, beginning there in the late summer of 1954. He completed Undergraduate Pilot Training at Webb Air Force Base, Texas, in 1955 went through gunnery training at Laughlin Air Force Base and Luke Air Force Base, Arizona. From April 1956 to July 1960, Scott flew with the 32d Tactical Fighter Squadron at Soesterberg Air Base, flying F-86 Sabres and F-100 Super Sabres; the weather in Northern Europe was poor, Scott's piloting skills were tested. Once, he had to land his plane on a golf course after a flameout. On another, he made it to a Dutch base on the edge of the North Sea. Scott served in Europe during the Cold War and tensions were high between the U. S. and Soviet Union. During the Hungarian Revolution of 1956, his squadron was placed on highest alert for weeks, but was stood down without going into combat. Scott hoped to advance his career by becoming a test pilot, hoped to be trained at Edwards Air Force Base, home to Chuck Yeager, first man to break the sound barrier.
He was counseled that the best way to get into test pilot school was to gain a graduate degree in aeronautic
The Lunar plaques are stainless steel commemorative plaques measuring 9 by 7 5⁄8 inches attached to the ladders on the descent stages of the United States Apollo Lunar Modules flown on lunar landing missions Apollo 11 through Apollo 17, to be left permanently on the lunar surface. The plaques were suggested and designed by NASA's head of technical services Jack Kinzler, who oversaw their production. All of the plaques bear facsimiles of the participating astronauts' signatures. For this reason, an extra plaque had to be made for Apollo 13 due to the late replacement of one crew member; the first and last plaques bear a facsimile of the signature of Richard Nixon, President of the United States during the landings, along with references to the start and completion of "man's first explorations of the Moon" and expressions of peace "for all mankind". All, except the Apollo 12 plaque, bear pictures of the two hemispheres of Earth. Apollo 17's plaque bears a depiction of the lunar globe in addition to the Earth.
The plaques used on missions 13 through 16 bear the call-sign of each mission's Lunar Module. All the plaques were left on the Moon, except the two for the aborted Apollo 13 mission which did not land on the Moon. Apollo 11 plaque inscription: "Here men from the planet Earth first set foot upon the Moon, July 1969 A. D. We came in peace for all mankind" in capital letters; the statement "We came in peace for all mankind" is derived from the 1958 National Aeronautics and Space Act's declaration of policy and purpose:"The Congress hereby declares that it is the policy of the United States that activities in space should be devoted to peaceful purposes for the benefit of all mankind."Apollo 12 plaque inscription: Apollo 12. November 1969 Apollo 13 plaque inscription: Apollo 13. Aquarius. April 1970 Apollo 14 plaque inscription: Apollo 14. Antares. February 1971 Apollo 15 plaque inscription: Apollo 15. Falcon. July 1971 Apollo 16 plaque inscription: Apollo 16. Orion. April 1972 Apollo 17 plaque inscription: "Here man completed his first explorations of the Moon, December 1972 A.
D. May the spirit of peace in which we came be reflected in the lives of all mankind" in capital letters.. The plaques are curved so as to fit around the landing leg and not hinder the astronauts from using the ladder; the plaques were attached directly to the ladder rungs, between the third and fourth rungs from the bottom. Two plaques were made for Apollo 13, because of the replacement of Command Module Pilot Thomas K. "Ken" Mattingly with John L. "Jack" Swigert two days before launch. Mission Commander James "Jim" Lovell was to have placed the plaque bearing Swigert's name over the original fastened to the LM Aquarius, when he descended the ladder to walk on the Moon; when the landing was aborted, Lovell saved this plaque to keep as a memento, it remains in his possession. The original plaque bearing Mattingly's name was destroyed when Aquarius reentered the Earth's atmosphere; the lunar near-side map, with the six Apollo lunar landing sites marked on it, was added to the Apollo 17 plaque at the suggestion of astronaut Gene Cernan.
Reproductions of the plaques were given as mementos to foreign governments through various United States embassies after each flight. James C. Humes, a speech writer for President Nixon and four other presidents, is credited for authoring the text on the Apollo 11 lunar plaque. William Safire and Pat Buchanan worked on drafting the plaque. In 1989, William Safire in his capacity as a "word maven" wryly wrote that AD should have been placed before the year, not after: "I had a hand in the first sign to be placed by earthlings on another celestial body, it contains a glaring grammatical error." Pioneer plaque
Apollo 11 was the spaceflight that landed the first two people on the Moon. Commander Neil Armstrong and lunar module pilot Buzz Aldrin, both American, landed the Apollo Lunar Module Eagle on July 20, 1969, at 20:17 UTC. Armstrong became the first person to step onto the lunar surface six hours on July 21 at 02:56:15 UTC, they spent about two and a quarter hours together outside the spacecraft, collected 47.5 pounds of lunar material to bring back to Earth. Command module pilot Michael Collins flew the command module Columbia alone in lunar orbit while they were on the Moon's surface. Armstrong and Aldrin spent 21.5 hours on the lunar surface before rejoining Columbia in lunar orbit. Apollo 11 was launched by a Saturn V rocket from Kennedy Space Center on Merritt Island, Florida, on July 16 at 13:32 UTC, was the fifth crewed mission of NASA's Apollo program; the Apollo spacecraft had three parts: a command module with a cabin for the three astronauts, the only part that returned to Earth. After being sent to the Moon by the Saturn V's third stage, the astronauts separated the spacecraft from it and traveled for three days until they entered lunar orbit.
Armstrong and Aldrin moved into Eagle and landed in the Sea of Tranquillity. The astronauts used Eagle's ascent stage to lift off from the lunar surface and rejoin Collins in the command module, they jettisoned Eagle before they performed the maneuvers that blasted them out of lunar orbit on a trajectory back to Earth. They returned to Earth and splashed down in the Pacific Ocean on July 24 after more than eight days in space. Armstrong's first step onto the lunar surface was broadcast on live TV to a worldwide audience, he described the event as "one small step for man, one giant leap for mankind." Apollo 11 ended the Space Race and fulfilled a national goal proposed in 1961 by President John F. Kennedy: "before this decade is out, of landing a man on the Moon and returning him safely to the Earth." In the late 1950s and early 1960s, the United States was engaged in the Cold War, a geopolitical rivalry with the Soviet Union. On October 4, 1957, the Soviet Union launched the first artificial satellite.
This surprise success fired imaginations around the world. It demonstrated that the Soviet Union had the capability to deliver nuclear weapons over intercontinental distances, challenged American claims of military and technological superiority; this precipitated the Sputnik crisis, triggered the Space Race. President Dwight D. Eisenhower responded to the Sputnik challenge by creating the National Aeronautics and Space Administration, initiating Project Mercury, which aimed to launch a man into Earth orbit, but on April 12, 1961, Soviet cosmonaut Yuri Gagarin became the first person in space, the first to orbit the Earth. It was another body blow to American pride. Nearly a month on May 5, 1961, Alan Shepard became the first American in space, completing a 15-minute suborbital journey. After being recovered from the Atlantic Ocean, he received a congratulatory telephone call from Eisenhower's successor, John F. Kennedy. Kennedy believed that it was in the national interest of the United States to be superior to other nations, that the perception of American power was at least as important as the actuality.
It was therefore intolerable that the Soviet Union was more advanced in the field of space exploration. He was determined that the United States should compete, sought a challenge that maximized its chances of winning. Since the Soviet Union had better booster rockets, he required a challenge, beyond the capacity of the existing generation of rocketry, one where the US and Soviet Union would be starting from a position of equality. Something spectacular if it could not be justified on military, economic or scientific grounds. After consulting with his experts and advisors, he chose such a project. On May 25, 1961, he addressed the United States Congress on "Urgent National Needs" and declared:I believe that this nation should commit itself to achieving the goal, before this decade is out, of landing a man on the moon and returning him safely to the Earth. No single space project in this period will be more impressive to mankind, or more important for the long-range exploration of space. We propose to accelerate the development of the appropriate lunar space craft.
We propose to develop alternate liquid and solid fuel boosters, much larger than any now being developed, until certain, superior. We propose additional funds for other engine development and for unmanned explorations-explorations which are important for one purpose which this nation will never overlook: the survival of the man who first makes this daring flight, but in a real sense, it will not be one man going to the Moon-if we make this judgment affirmatively, it will be an entire nation. For all of us must work to put him there; the effort to land a man on the Moon had a name: Project Apollo. An early and crucial decision was choosing lunar orbit rendezvous over both direct ascent and Earth orbit rendezvous. A space rendezvous is an orbital maneuver in which two spacecraft navigate through space and meet up. On July 11, 1962, James Webb announced the decision to use lunar orbit rendezvous; this resulted in a much smaller launch vehicle, in the Apollo spacecraft being composed of three major parts: a command module with a cabin for the three astr
Apollo Lunar Surface Experiments Package
The Apollo Lunar Surface Experiments Package comprised a set of scientific instruments placed by the astronauts at the landing site of each of the five Apollo missions to land on the Moon following Apollo 11. Apollo 11 left a smaller package called the Early Apollo Scientific Experiments Package, or EASEP; the instrumentation and experiments that would comprise ALSEP were decided in February 1966. The experiments, institutions responsible, principal investigators and coinvestigators were: Passive Lunar Seismic Experiment: Massachusetts Institute of Technology, Frank Press. Medium-Energy Solar Wind: Jet Propulsion Laboratory, C. W. Snyder and M. M. Neugebauer. Suprathermal Ion Detection: Rice University, J. W. Freeman, Jr.. Lunar Heat Flow Management: Columbia University, M. Langseth. Low-Energy Solar Wind: Rice University, B. J. O'Brien. Active Lunar Seismic Experiment: Stanford University, R. L. Kovach; the ALSEP was tested by Bendix Aerospace in Ann Arbor, Michigan. The instruments were designed to run autonomously after the astronauts left and to make long-term studies of the lunar environment.
They were arrayed around a Central Station which supplied power generated by a radioisotope thermoelectric generator to run the instruments and communications so data collected by the experiments could be relayed to Earth. Thermal control was achieved by passive elements as well as power dissipation heaters. Data collected from the instruments were transmitted to Earth; the ALSEP was stored in the Lunar Module's Scientific Equipment Bay in two separate subpackages. The base of the first subpackage formed the Central Station while the base of the second subpackage was part of the RTG. A subpallet was attached to the second subpackage which carried one or two of the experiments and the antenna gimbal assembly. On Apollo 12, 13, 14, the second subpackage stored the Lunar Hand Tool Carrier; the exact deployment of experiments differed by mission. The following pictures show a typical procedure from Apollo 12; each ALSEP station had some common elements. Each mission had a different array of experiments.
Because of the risk of an early abort on the Moon, geologists persuaded NASA to permit only experiments that could be set up or completed in 10 minutes. As a result, Apollo 11 did not leave a full ALSEP package, but left a simpler version called the Early Apollo Surface Experiments Package. Since there was only one 2 hour 40 minute EVA planned, the crew would not have enough time to deploy a full ALSEP, which took one to two hours to deploy. Both packages were stored in the LM's SEQ bay. Engineers designed the EASEP to deploy with one squeeze handle, the Laser Ranging Retro Reflector deployed within ten minutes. Despite the simpler design, the seismometer was sensitive enough to detect Neil Armstrong's movements during sleep; the antenna gimbal assembly was stored on the subpallet. The stool for the PSE, the ALSEP tools, HTC was stored on the second subpackage; because of the aborted landing, none of the experiments were deployed. However, the Apollo 13 S-IVB stage was deliberately crashed on the Moon to provide a signal for the Apollo 12 PSE.
The antenna gimbal assembly was stored on the first subpackage. The stool for the PSE, the ALSEP tools and the Lunar drill was stored on the subpallet; the HTC was stored on the second subpackage. The antenna gimbal assembly was stored on the subpallet; the stool for the PSE, the ALSEP tools, HTC was stored on the second subpackage. The antenna gimbal assembly was stored on the subpallet; the ALSEP tools and stool for the PSE was stored on the second subpackage. The ALSEP system and instruments were controlled by commands from Earth; the stations ran from deployment until they were turned off on 30 September 1977 due to budgetary considerations. Additionally, by 1977 the power packs could not run both the transmitter and any other instrument, the ALSEP control room was needed for the attempt to reactivate Skylab. ALSEP systems are visible in several images taken by the Lunar Reconnaissance Orbiter during its orbits over Apollo landing sites. Apollo program Lunar laser ranging experiment Hexanitrostilbene, a vacuum stable explosive used in the ALSEP.
Lunar Roving Vehicle ^ Encyclopedia Astronautica website, 14 February 1966 entry. Brzostowski, M. A. and Brzostowski, A. C. Archiving the Apollo active seismic data, The Leading Edge, Society of Exploration Geophysicists, April, 2009. Astronautix Site ALSEP Page @ myspacemuseum.com NSSDC Apollo Page Apollo Scientific Experiments Data Handbook ALSEP Termination Report Catalog of Apollo Experiment Operations Apollo Lunar Surface Experiments Package, Design Certification Review Archive of ALSEP documents, from the Lunar and Planetary Institute
The kilogram or kilogramme is the base unit of mass in the International System of Units. Until 20 May 2019, it remains defined by a platinum alloy cylinder, the International Prototype Kilogram, manufactured in 1889, stored in Saint-Cloud, a suburb of Paris. After 20 May, it will be defined in terms of fundamental physical constants; the kilogram was defined as the mass of a litre of water. That was an inconvenient quantity to replicate, so in 1799 a platinum artefact was fashioned to define the kilogram; that artefact, the IPK, have been the standard of the unit of mass for the metric system since. In spite of best efforts to maintain it, the IPK has diverged from its replicas by 50 micrograms since their manufacture late in the 19th century; this led to efforts to develop measurement technology precise enough to allow replacing the kilogram artifact with a definition based directly on physical phenomena, now scheduled to take place in 2019. The new definition is based on invariant constants of nature, in particular the Planck constant, which will change to being defined rather than measured, thereby fixing the value of the kilogram in terms of the second and the metre, eliminating the need for the IPK.
The new definition was approved by the General Conference on Weights and Measures on 16 November 2018. The Planck constant relates a light particle's energy, hence mass, to its frequency; the new definition only became possible when instruments were devised to measure the Planck constant with sufficient accuracy based on the IPK definition of the kilogram. The gram, 1/1000 of a kilogram, was provisionally defined in 1795 as the mass of one cubic centimetre of water at the melting point of ice; the final kilogram, manufactured as a prototype in 1799 and from which the International Prototype Kilogram was derived in 1875, had a mass equal to the mass of 1 dm3 of water under atmospheric pressure and at the temperature of its maximum density, 4 °C. The kilogram is the only named SI unit with an SI prefix as part of its name; until the 2019 redefinition of SI base units, it was the last SI unit, still directly defined by an artefact rather than a fundamental physical property that could be independently reproduced in different laboratories.
Three other base units and 17 derived units in the SI system are defined in relation to the kilogram, thus its stability is important. The definitions of only eight other named SI units do not depend on the kilogram: those of temperature and frequency, angle; the IPK is used or handled. Copies of the IPK kept by national metrology laboratories around the world were compared with the IPK in 1889, 1948, 1989 to provide traceability of measurements of mass anywhere in the world back to the IPK; the International Prototype Kilogram was commissioned by the General Conference on Weights and Measures under the authority of the Metre Convention, in the custody of the International Bureau of Weights and Measures who hold it on behalf of the CGPM. After the International Prototype Kilogram had been found to vary in mass over time relative to its reproductions, the International Committee for Weights and Measures recommended in 2005 that the kilogram be redefined in terms of a fundamental constant of nature.
At its 2011 meeting, the CGPM agreed in principle that the kilogram should be redefined in terms of the Planck constant, h. The decision was deferred until 2014. CIPM has proposed revised definitions of the SI base units, for consideration at the 26th CGPM; the formal vote, which took place on 16 November 2018, approved the change, with the new definitions coming into force on 20 May 2019. The accepted redefinition defines the Planck constant as 6.62607015×10−34 kg⋅m2⋅s−1, thereby defining the kilogram in terms of the second and the metre. Since the second and metre are defined in terms of physical constants, the kilogram is defined in terms of physical constants only; the avoirdupois pound, used in both the imperial and US customary systems, is now defined in terms of the kilogram. Other traditional units of weight and mass around the world are now defined in terms of the kilogram, making the kilogram the primary standard for all units of mass on Earth; the word kilogramme or kilogram is derived from the French kilogramme, which itself was a learned coinage, prefixing the Greek stem of χίλιοι khilioi "a thousand" to gramma, a Late Latin term for "a small weight", itself from Greek γράμμα.
The word kilogramme was written into French law in 1795, in the Decree of 18 Germinal, which revised the older system of units introduced by the French National Convention in 1793, where the gravet had been defined as weight of a cubic centimetre of water, equal to 1/1000 of a grave. In the decree of 1795, the term gramme thus replaced gravet, kilogramme replaced grave; the French spelling was adopted in Great Britain when the word was used for the first time in English in 1795, with the spelling kilogram being adopted in the United States. In the United Kingdom both spellings are used, with "kilogram" having become by far the more common. UK law regulating the units to be used when trading by weight or measure does not prevent the use of either spelling. In the 19th century the French word kilo, a shortening of kilogramme, was imported into the English language where it has been used to mean both kilogram and kilometre. While kilo is acceptable in many generalist texts
Lunokhod 2 was the second of two unmanned lunar rovers landed on the Moon by the Soviet Union as part of the Lunokhod programme. The Luna 21 spacecraft landed on the Moon and deployed the second Soviet lunar rover, Lunokhod 2, in January 1973; 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, study the soil mechanics of the lunar surface material. The rover had a mass of 840 kg, it was about 170 centimetres long and 160 centimetres wide and had eight wheels each with an independent suspension, electric motor and brake. The rover had about 1 and 2 km/h. Lunokhod 2 was equipped with three television cameras, one mounted high on the rover for navigation, which could return high resolution images at different frame rates—3.2, 5.7, 10.9 or 21.1 seconds per frame. These images were used by a five-man team of controllers on Earth who sent driving commands to the rover in real time.
Power was supplied by a solar panel on the inside of a round hinged lid which covered the instrument bay, which would charge the batteries when opened. A polonium-210 radioisotope heater unit was used to keep the rover warm during the long lunar nights. There were four panoramic cameras mounted on the rover. Scientific instruments included a soil mechanics tester, solar X-ray experiment, an astrophotometer to measure visible and ultraviolet light levels, a magnetometer deployed in front of the rover on the end of a 2.5 m boom, a radiometer, a photodetector for laser detection experiments, a French-supplied laser corner reflector. The lander carried the State Emblem of the Soviet Union; the lander and rover together massed 1814 kg. The Proton-K/D launcher put the spacecraft into Earth parking orbit followed by translunar injection. On January 12, 1973 Luna 21 was braked into a 90 by 100 km lunar orbit. On January 13 and 14, the perilune was lowered to 16 km altitude. On January 15 after 40 orbits, the braking rocket was fired at 16 km altitude, the craft began to de-orbit.
At an altitude of 750 m the main thrusters began firing, slowing the fall until a height of 22 m was reached. At this point the main thrusters shut down and the secondary thrusters ignited, slowing the fall until the lander was 1.5 m above the surface, where the engine was switched off. Landing occurred at 23:35 UT in Le Monnier crater at 25.85 degrees N, 30.45 degrees E. After landing, the Lunokhod 2 took TV images of the surrounding area rolled down a ramp to the surface at 01:14 UT on January 16 and took pictures of the Luna 21 lander and landing site, driving for 30 metres. After a period of charging up its batteries, it took more pictures of the site and the lander, set off to explore the moon; the rover would run during the lunar day, stopping to recharge its batteries with the solar panels. At night the rover hibernated until the next sunrise, heated by the radioactive source. January 18, 1973 to January 24, 1973: The rover drives 1,260 metres February 8 to 23: The rover drives 9,086 metres further March 11 to 23: The rover drives 16,533 metres further April 9 to 22: The rover drives 8,600 metres further May 8 to June 3: The rover drives 880 metres further On June 4, 1973 it was announced that the program was completed, leading to speculation that the vehicle failed in mid-May or could not be revived after the lunar night of May–June.
More Alexander Basilevsky related an account in which on May 9, the rover's open lid touched a crater wall and became covered with dust. When the lid was closed, this dust was dumped on to the radiators; the following day, May 10, controllers saw the internal temperature of Lunokhod 2 climb as it was unable to cool itself rendering the rover inoperable. On May 11, signal from the rover was lost. Lunokhod 2 operated for about four months, the original estimate was that it covered 37 km of terrain, including hilly upland areas and rilles, sent back 86 panoramic images and over 80,000 TV pictures. Many mechanical tests of the surface, laser ranging measurements, other experiments were completed during this time. Lunokhod 2 was thought to have covered 37 km based on wheel rotations but Russian scientists at the Moscow State University of Geodesy and Cartography revised that to an estimated distance of about 42.1–42.2 km based on Lunar Reconnaissance Orbiter images of the lunar surface. Subsequent discussions with their American counterparts ended with an agreed-upon final distance of 39 km.
The Lunokhod rover held the record for off-Earth roving distance until July 27, 2014, when NASA's Mars Opportunity rover exceeded it after having traveled over 40 km. Lunokhod 2 continues to be detected by lunar laser ranging experiments and its position is known to sub-meter accuracy. On March 17, 2010 Phil Stooke at the University of Western Ontario announced that he had located Lunokhod 2 in NASA Lunar Reconnaissance Orbiter images, but images showed the initial identification was incorrect, the LRO LROC team identified the correct location of the rover in March 2012. Excellent Luno
The equirectangular projection is a simple map projection attributed to Marinus of Tyre, who Ptolemy claims invented the projection about AD 100. The projection maps meridians to vertical straight lines of constant spacing, circles of latitude to horizontal straight lines of constant spacing; the projection is neither equal area nor conformal. Because of the distortions introduced by this projection, it has little use in navigation or cadastral mapping and finds its main use in thematic mapping. In particular, the plate carrée has become a standard for global raster datasets, such as Celestia and NASA World Wind, because of the simple relationship between the position of an image pixel on the map and its corresponding geographic location on Earth; the forward projection transforms. The reverse projection transforms from the plane back onto the sphere; the formulae presume a spherical model and use these definitions: λ is the longitude of the location to project. X = cos φ 1 y = The plate carrée, is the special case.
This projection maps x to be the value of the longitude and y to be the value of the latitude, therefore is sometimes called the latitude/longitude or lat/lon projection or is said to be “unprojected”. While a projection with spaced parallels is possible for an ellipsoidal model, it would no longer be equidistant because the distance between parallels on an ellipsoid is not constant. More complex formulae can be used to create an equidistant map whose parallels reflect the true spacing. Λ = x cos φ 1 + λ 0 φ = y + φ 1 List of map projections Cartography Cassini projection Gall–Peters projection with resolution regarding the use of rectangular world maps Mercator projection Spherical image projection Global MODIS based satellite map The blue marble: land surface, ocean color and sea ice. Table of examples and properties of all common projections, from radicalcartography.net. Panoramic Equirectangular Projection, PanoTools wiki. Equidistant Cylindrical in proj4