NationMaster - Encyclopedia: Ranger program

The Ranger program was a series of unmanned 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 collide with the lunar surface, returning imagery until they were destroyed upon impact. It has been suggested that Space probe be merged into this article or section. ... Apparent magnitude: up to -12. ...

Ranger was originally designed, beginning in 1959, in three distinct phases, called "blocks". Each block had different mission objectives and progressively more advanced system design. The JPL mission designers planned multiple launches in each block, to maximize the engineering experience and scientific value of the mission and to assure at least one successful flight. Total research, development, launch, and support costs for the Ranger series of spacecraft (Rangers 1 through 9) was approximately $170 million. The JPL complex in Pasadena, Ca. ...

The Ranger spacecraft

Each Ranger spacecraft had six cameras on board. The cameras were fundamentally the same with differences in exposure times, fields of view, lenses, and scan rates. The camera system was divided into two channels, P (partial) and F (full). Each channel was self-contained with separate power supplies, timers, and transmitters. The F-channel had two cameras: the wide-angle A-camera and the narrow angle B-camera. The P-channel had four cameras: P1 and P2 (narrow angle) and P3 and P4 (wide angle). The final F-channel image was taken between 2.5 and 5 seconds before impact (altitude about 5 km) and the last P-channel image 0.2 to 0.4 seconds before impact (altitude about 600 m). The images provided better resolution than was available from Earth based views by a factor of 1000.

Mission list

Block 1 missions

Block 1, consisting of two spacecraft launched into Earth orbit in 1961, was intended to test the Atlas/Agena launch vehicle and spacecraft equipment without attempting to reach the Moon. Ranger Block 1 diagram. ... Ranger Block 1 diagram. ... Ranger 1 was a spacecraft in the Ranger program whose primary mission was to test the performance of those functions and parts necessary for carrying out subsequent lunar and planetary missions. ... is the 235th day of the year (236th in leap years) in the Gregorian calendar. ... Year 1961 (MCMLXI) was a common year starting on Sunday (link will display full calendar) of the Gregorian calendar. ... Ranger 2 was a flight test of the Ranger spacecraft system of the Ranger program designed for future lunar and interplanetary missions. ... is the 322nd day of the year (323rd in leap years) in the Gregorian calendar. ... Year 1961 (MCMLXI) was a common year starting on Sunday (link will display full calendar) of the Gregorian calendar. ... Mercury Atlas 9 rocket and capsule on pad The Atlas is a venerable line of space launch vehicles built by Lockheed Martin. ... The Agena was a rocket upper stage developed by Lockheed for the ill-fated WS-117L US reconnaissance satellite program. ...

Most elements of spacecraft technology taken for granted today were untested before Ranger. Perhaps the most important of these was three-axis attitude stabilization, meaning that the spacecraft is fixed in relation to space instead of being stabilized by spinning. This would permit pointing large solar panels at the Sun, a large antenna at Earth, and cameras and other directional scientific sensors at their appropriate targets. Rocket propulsion carried aboard the spacecraft was another critically important new technology, needed for accurate targeting at the Moon or distant planets.

In addition, two-way communication and closed-loop tracking, requiring spacecraft and ground system development, and the use of on-board computing and sequencing combined with commands from the ground, all had to be developed and tried out in flight. Unfortunately, problems with the early version of the launch vehicle left Ranger 1 and Ranger 2 in short-lived, low-Earth orbits in which the spacecraft could not stabilize themselves, collect solar power, or survive for long. In 1962, JPL utilized the Ranger 1 and Ranger 2 design for the failed Mariner 1 and successful Mariner 2 deep-space probes to Venus. Ranger 1 was a spacecraft in the Ranger program whose primary mission was to test the performance of those functions and parts necessary for carrying out subsequent lunar and planetary missions. ... Ranger 2 was a flight test of the Ranger spacecraft system of the Ranger program designed for future lunar and interplanetary missions. ... Year 1962 (MCMLXII) was a common year starting on Monday (the link is to a full 1962 calendar) of the Gregorian calendar. ... Launch of Mariner 1 Mariner 1 was the first spacecraft of the Mariner program. ... -1... (*min temperature refers to cloud tops only) Atmospheric characteristics Atmospheric pressure 9. ...

Block 2 missions

Block 2 of the Ranger project launched three spacecraft to the Moon in 1962, carrying a TV camera, a radiation detector, and a seismometer in a separate capsule slowed by a rocket motor and packaged to survive its low-speed impact on the Moon’s surface. The three missions together demonstrated good performance of the Atlas/Agena B launch vehicle and the adequacy of the spacecraft design, but unfortunately not all on the same attempt. Ranger 3 was launched into deep space, but an inaccuracy put it off course and it missed the Moon entirely. Ranger 4 had a perfect launch, but the spacecraft was completely disabled. The project team tracked the seismometer capsule to impact just out of sight on the lunar far side, validating the communications and navigation system. Ranger 5 missed the Moon and was disabled. No significant science information was gleaned from these missions. The craft weighed 331 kg. Range 5 spacecraft diagram. ... Range 5 spacecraft diagram. ... Ranger 3 was a spacecraft of the Ranger program that was launched to study the Moon on January 26, 1962. ... is the 26th day of the year in the Gregorian calendar. ... Year 1962 (MCMLXII) was a common year starting on Monday (the link is to a full 1962 calendar) of the Gregorian calendar. ... Ranger 4 was a spacecraft of the Ranger program designed to transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to impacting on the Moon, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight... April 23 is the 113th day of the year (114th in leap years) in the Gregorian calendar. ... Year 1962 (MCMLXII) was a common year starting on Monday (the link is to a full 1962 calendar) of the Gregorian calendar. ... Ranger 5 was a spacecraft of the Ranger program designed to transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to impacting on the Moon, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight... is the 291st day of the year (292nd in leap years) in the Gregorian calendar. ... Year 1962 (MCMLXII) was a common year starting on Monday (the link is to a full 1962 calendar) of the Gregorian calendar. ... Ranger 3 was a spacecraft of the Ranger program that was launched to study the Moon on January 26, 1962. ... Ranger 4 was a spacecraft of the Ranger program designed to transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to impacting on the Moon, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight... Far side of the Moon. ... Ranger 5 was a spacecraft of the Ranger program designed to transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to impacting on the Moon, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight...

Block 3 missions

Ranger's Block 3 embodied four launches in 1964-65. These spacecraft boasted a television instrument designed to observe the lunar surface during the approach; as the spacecraft neared the Moon, they would reveal detail smaller than the best Earth telescopes could show, and finally details down to dishpan size. The first of the new series, Ranger 6, had a flawless flight, except that the television system was disabled by an in-flight accident and could take no pictures. Image File history File links Ranger_6789. ... Image File history File links Ranger_6789. ... Ranger 6 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. ... is the 30th day of the year in the Gregorian calendar. ... 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ... First image of the Moon taken by a US spacecraft. ... is the 209th day of the year (210th in leap years) in the Gregorian calendar. ... 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ... is the 212th day of the year (213th in leap years) in the Gregorian calendar. ... 1964 (MCMLXIV) was a leap year starting on Wednesday (the link is to a full 1964 calendar). ... Mare Cognitum (the sea that has become known) is a lunar mare located in a basin or large crater which sits in the second ring of the Procellarum basin. ... Ranger 8 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. ... February 17 is the 48th day of the year in the Gregorian calendar. ... Year 1965 (MCMLXV) was a common year starting on Friday (link will display full calendar) of the 1965 Gregorian calendar. ... is the 51st day of the year in the Gregorian calendar. ... Year 1965 (MCMLXV) was a common year starting on Friday (link will display full calendar) of the 1965 Gregorian calendar. ... The Sea of Tranquility of the Moon. ... Ranger 9 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. ... March 21 is the 80th day of the year (81st in leap years) in the Gregorian calendar. ... Year 1965 (MCMLXV) was a common year starting on Friday (link will display full calendar) of the 1965 Gregorian calendar. ... is the 83rd day of the year (84th in leap years) in the Gregorian calendar. ... Year 1965 (MCMLXV) was a common year starting on Friday (link will display full calendar) of the 1965 Gregorian calendar. ... Alphonsus is an ancient impact crater on Earths Moon that dates from the immediate post-Nectarian era. ... Ranger 6 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. ...

The next three Rangers, with a redesigned television, were completely successful. Ranger 7 photographed its way down to target in a lunar plain, soon named Mare Cognitum, south of Copernicus crater. It sent more than 4,300 pictures from six cameras to waiting scientists and engineers. The new images revealed that craters caused by impact were the dominant features of the Moon's surface, even in the seemingly smooth and empty plains. Great craters were marked by small ones, and the small with tiny impact pockmarks, as far down in size as could be discerned—about 50 centimeters (16 inches). The light-colored streaks radiating from Copernicus and a few other large craters turned out to be chains and nets of small craters and debris blasted out in the primary impacts. First image of the Moon taken by a US spacecraft. ... Mare Cognitum (the sea that has become known) is a lunar mare located in a basin or large crater which sits in the second ring of the Procellarum basin. ... Copernicus is a prominent lunar impact crater located on the eastern Oceanus Procellarum. ...

In February 1965, Ranger 8 swept an oblique course over the south of Oceanus Procellarum and Mare Nubium, to crash in Mare Tranquillitatis where Apollo 11 would land 4½ years later. It garnered more than 7,000 images, covering a wider area and reinforcing the conclusions from Ranger 7. About a month later, Ranger 9 came down in the 90 km diameter (55 mile) crater Alphonsus. Its 5,800 images, nested concentrically and taking advantage of very low-level sunlight, provided strong confirmation of the crater-on-crater, gently rolling contours of the lunar surface. Ranger 8 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. ... The Ocean of Storms of the Moon. ... The Sea of Clouds of the Moon. ... The Sea of Tranquility of the Moon. ... The Apollo 11 mission was the first manned mission to land on the Moon. ... Ranger 9 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. ... Alphonsus is an ancient impact crater on Earths Moon that dates from the immediate post-Nectarian era. ...

Thus, after a long trouble-plagued start that taught the system engineers a great deal and the scientists very little, Project Ranger finished with three flights that greatly advanced the lunar scientists' knowledge of the surface and whetted their appetites for a closer look.

External links

Both links lead to a whole book on the program. For the HTML one, scroll down to see the table of contents link.

See also

Photograph of Surveyor(3) lunar landing spacecraft taken by Apollo 12 astronauts (descriptions added). ... Lunar orbiter spacecraft (NASA) The Lunar Orbiter program was a series of five unmanned Lunar orbiter missions launched by the United States in 1966 through 1967 with the purpose of mapping the lunar surface before the Apollo landings. ... For other uses, see Apollo (disambiguation). ... The Luna programme (occasionally called Lunik) was a series of unmanned space missions sent to the Moon by the Soviet Union between 1959 and 1976. ...

Categories: Ranger program | Lunar spacecraft Download high resolution version (526x642, 129 KB) Ranger Block III spacecraft (NASA) Downloaded from NASA NIX Website: http://nix. ... Photograph of Surveyor(3) lunar landing spacecraft taken by Apollo 12 astronauts (descriptions added). ... Lunar orbiter spacecraft (NASA) The Lunar Orbiter program was a series of five unmanned Lunar orbiter missions launched by the United States in 1966 through 1967 with the purpose of mapping the lunar surface before the Apollo landings. ... Ranger 1 was a spacecraft in the Ranger program whose primary mission was to test the performance of those functions and parts necessary for carrying out subsequent lunar and planetary missions. ... Ranger 2 was a flight test of the Ranger spacecraft system of the Ranger program designed for future lunar and interplanetary missions. ... Ranger 3 was a spacecraft of the Ranger program that was launched to study the Moon on January 26, 1962. ... Ranger 4 was a spacecraft of the Ranger program designed to transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to impacting on the Moon, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight... Ranger 5 was a spacecraft of the Ranger program designed to transmit pictures of the lunar surface to Earth stations during a period of 10 minutes of flight prior to impacting on the Moon, to rough-land a seismometer capsule on the Moon, to collect gamma-ray data in flight... Ranger 6 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. ... First image of the Moon taken by a US spacecraft. ... Ranger 8 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. ... Ranger 9 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. ... The National Aeronautics and Space Administration (NASA) is an agency of the United States federal government, responsible for the nations public space program. ... The Explorer program was the United Statess first successful attempt to launch an artificial satellite . ... Voyager Project redirects here. ... NASAs New Millennium program is focused on engineering validation of new technologies for space applications. ... NASAs Discovery Program is a series of lower-cost, highly focused scientific space missions. ... NASAs New Frontiers Program is a series of medium-cost (not to exceed 700 million), highly focused scientific space missions. ... Artists Concept of Rover on Mars (credit: Maas Digital LLC) NASAs Mars Exploration Rover (MER) Mission is an ongoing robotic Mars exploration mission, commenced in 2003, that sent two rovers â€” Spirit and Opportunity â€” to explore the Martian surface and geology. ... Nuclear reactors may be used to power ion engines such as this one used on Deep Space 1 Project Prometheus was established in 2003 by NASA to develop nuclear-powered systems for long-duration space missions. ... Project Constellation is NASAs current plan for space exploration. ... The Mars Scout Program is a new NASA program of small, low-cost missions to Mars, selected from innovative proposals by the scientific community. ... The Mars Scout Program is a new NASA program of small, low-cost missions to Mars, selected from innovative proposals by the scientific community. ... The US Pioneer program of unmanned space missions was designed for planetary exploration. ... Launch of Mariner 1 (NASA) The Mariner program was a program conducted by the American space agency NASA that launched a series of robotic interplanetary probes designed to investigate Mars, Venus and Mercury. ... Lunar orbiter spacecraft (NASA) The Lunar Orbiter program was a series of five unmanned Lunar orbiter missions launched by the United States in 1966 through 1967 with the purpose of mapping the lunar surface before the Apollo landings. ... Photograph of Surveyor(3) lunar landing spacecraft taken by Apollo 12 astronauts (descriptions added). ... For other uses, see Apollo (disambiguation). ... Viking mission profile. ... NASAs Planetary Observer series was still birthed, resulting in only one, failed, mission. ... Mariner Mark II was NASAs planned family of unmanned spacecraft for the exploration of the outer solar system that were to be developed and operated by JPL between 1990 thru the year 2010. ... The Mars Surveyor 98 program comprised two spacecraft launched separately, the Mars Climate Orbiter (formerly the Mars Surveyor 98 Orbiter) and the Mars Polar Lander (formerly the Mars Surveyor 98 Lander); on board the Mars Polar Lander spacecraft were two surface-penetrator probes (Deep Space 2). ... For other uses of the term Grand Tour, see Grand Tour (disambiguation) The Planetary Grand Tour was an ambitious plan to send unmanned probes to the outermost planets of the solar system. ... The Voyager program was a planned series of unmanned NASA probes to Mars. ...

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