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A space rendezvous between two spacecraft, often between a spacecraft and a space station, is an orbital maneuver where the two arrive at the same orbit, make their orbital velocities the same, and bring them together (an approach maneuver, taxiing maneuver); it may or may not include docking.
Historic rendezvousOn August 12, 1962 Vostok 3 and Vostok 4 were placed into nearby orbits and passed within several kilometers of each other, but did not have the orbital maneuvering capability to perform a space rendezvous. This was also the case on June 16, 1963 when Vostok 5 and Vostok 6 were launched into nearby orbits. G. Salakhutdinov, in a Russian periodical from 19901, relates the following quote:
The first space rendezvous took place on December 15, 1965, when Gemini 6A maneuvered within 30 cm of the passive Gemini 7. Astronaut Wally Schirra accomplished the task. The spacecraft were not equipped to dock and no physical contact took place. The first space rendezvous with docking took place on March 16, 1966, when Gemini 8, under the command of Neil Armstrong, rendezvoused and docked with the uncrewed Agena 8 target vehicle. The Soviets carried out the first automated (and unmanned) space docking between Cosmos 186 and Cosmos 188 on 1967-10-30.2 Another kind of rendezvous occurred in 1969, when astronauts moonwalked from the lunar module of Apollo 12 to the landing site of Surveyor 3, which had made a soft landing in 1967. Parts of the Surveyor were brought back. The first rendezvous of two spacecraft from different countries took place on June 17, 1975, when an Apollo spacecraft docked with a Soyuz spacecraft as part of the Apollo-Soyuz Test Project. The first rendezvous and docking of three spacecraft took place when both Soyuz 26 and Soyuz 27 were docked to the Salyut 6 space station during January 1978. UsesA frequent use of space rendezvous has been the transportation of crew and supplies to orbiting space stations. The first of these was the rendezvous and docking on 7 June 1971 of the ill-fated Soyuz 11 mission with the Salyut 1 station. In the past, human spaceflight missions have made rendezvous with each of six Salyut stations, with Skylab, with Mir and with the International Space Station (ISS). Currently both Soyuz spacecraft and Space Shuttles are used to bring crew to the ISS. Robotic spacecraft are also used to rendezvous with and resupply space stations. Soyuz and Progress spacecraft have automatically docked with both Mir3 and the ISS using the Kurs docking system, while the Automated Transfer Vehicle has docked with ISS using a laser system. The robotic H-II Transfer Vehicle, however, is planned to fly to a close rendezvous without docking, in order to allow the ISS's Canadarm2 to bring it into dock. Space rendezvous have been used for a variety of other purposes, including recent service missions to the Hubble Space Telescope. Historically, for the missions of Project Apollo that landed astronauts on the Moon, the ascent stage of the Apollo Lunar Module would rendezvous and dock with the Apollo Command/Service Module in lunar orbit rendezvous maneuvers. Also, the STS-49 crew rendezvoused with and attached a rocket motor to the Intelsat VI (F-3) communications satellite to allow it to make an orbital maneuver. Possible future rendezvous may be made by a yet to be developed automated Hubble Robotic Vehicle (HRV), and by the CX-OLEV, which is being developed for rendezvous with a geosynchronous satellite that has run out of fuel. The CX-OLEV would take over orbital stationkeeping and/or finally bring the satellite to a graveyard orbit, after which the CX-OLEV can possibly be reused for another satellite. Gradual transfer from the geostationary transfer orbit to the geosynchronous orbit will take a number of months, using Hall effect thrusters. [1] Alternatively the two spacecraft are already together, and just undock and dock in a different way:
Anti-satellite weapons partly fall under the category of hostile rendezvous. Kinetic projectiles do not use explosives or radiation, but just collide. Methods
The standard technique for rendezvous and docking is to dock an active vehicle with a passive target. This technique has been used successfully for the Gemini, Apollo, Apollo/Soyuz, Salyut, Skylab, Mir, and ISS programs. The active vehicle is first put on an intercept course with the target. The closure rate is then reduced by use of the active vehicle's reaction control system. Docking typically occurs at a rate of 0.1 ft/s (0.030 m/s) to 0.2 ft/s (0.061 m/s).4
STS-104 was the third Space Shuttle mission to conduct a V-bar arrival at the International Space Station.5
Astrotech has proposed meeting ISS cargo needs with a vehicle which would approach the station, "using a traditional nadir R-bar approach."6 References
See alsoExternal links
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