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“This 1967 Navy film explains the highly successful Navy Navigation Satellite System (NAVSAT), which was built during the 1960’s, and operated through 1996. It includes a detailed explanation of the computing equipment used to operate the system in the 1960’s. Source: Naval History and Heritage Command, Photographic Section, UMO-40.”
NEW VERSION with improved video & sound:
Public domain film from the Naval History and Heritage Command, slightly cropped to remove uneven edges, with the aspect ratio corrected, and 1-pass exposure & color correction applied (cannot be ideal in all scenes).
The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).
The TRANSIT system, also known as NAVSAT (for Navy Navigation Satellite System), was the first satellite navigation system to be used operationally. The system was primarily used by the U.S. Navy to provide accurate location information to its Polaris ballistic missile submarines, and it was also used as a navigation system by the Navy’s surface ships, as well as for hydrographic and geodetic surveying. Transit provided continuous navigation satellite service from 1964, initially for Polaris submarines and later for civilian use as well…
The TRANSIT satellite system was developed by the Applied Physics Laboratory (APL) of Johns Hopkins University for the U.S. Navy. Just days after the Soviet launch of Sputnik 1, the first man-made earth-orbiting satellite on October 4, 1957. Two physicists at APL, William Guier and George Weiffenbach, found themselves in discussion about the microwave signals that would likely be emanating from the satellite and were able to determine Sputnik’s orbit by analyzing the Doppler shift of its radio signals during a single pass. Frank McClure, the chairman of APL’s Research Center, suggested that if the satellite’s position were known and predictable, the Doppler shift could be used to locate a receiver on Earth.
Development of the TRANSIT system began in 1958, and a prototype satellite, Transit 1A, was launched in September 1959. That satellite failed to reach orbit. A second satellite, Transit 1B, was successfully launched April 13, 1960, by a Thor-Ablestar rocket. The first successful tests of the system were made in 1960, and the system entered Naval service in 1964.
It is noteworthy that surveyors used Transit to locate remote benchmarks by averaging dozens of Transit fixes, producing sub-meter accuracy. In fact, the elevation of Mount Everest was corrected in the late 1980s by using a Transit receiver to re-survey a nearby benchmark.
Thousands of warships, freighters and private watercraft used Transit from 1967 until 1991. Some Soviet warships were equipped with Motorola NavSat receivers.
The TRANSIT system was made obsolete by the Global Positioning System, and ceased navigation service in 1996. Improvements in electronics allowed the GPS system to effectively take several fixes at once, greatly reducing the complexity of deducing a position. The GPS system uses many more satellites than were used with TRANSIT, allowing the system to be used continuously, while TRANSIT provided a fix only every hour or more.
After 1996, the satellites were kept in use as spaceborne ‘mailboxes’ and for the Navy’s Ionospheric Monitoring System…
A satellite navigation or SAT NAV system is a system of satellites that provide autonomous geo-spatial positioning with global coverage. It allows small electronic receivers to determine their location (longitude, latitude, and altitude) to within a few metres using time signals transmitted along a line-of-sight by radio from satellites. Receivers calculate the precise time as well as position, which can be used as a reference for scientific experiments. A satellite navigation system with global coverage may be termed a global navigation satellite system or GNSS.
As of October 2011, only the United States NAVSTAR Global Positioning System (GPS) and the Russian GLONASS are fully globally operational GNSSs. China is in the process of expanding its regional Beidou navigation system into the global Compass navigation system by 2020. The European Union’s Galileo positioning system is a GNSS in initial deployment phase, scheduled to be fully operational by 2020 at the earliest. Several countries including France, Japan and India. are in the process of developing regional navigation systems.
Global coverage for each system is generally achieved by a satellite constellation of 20–30 medium Earth orbit (MEO) satellites spread between several orbital planes…
