History of Navigation - Modern Times

Modern Times

In 1714, the British Commissioners for the discovery of longitude at sea came into prominence. This group, which existed until 1828, offered grants and rewards for the solution of various navigational problems. Between 1737 and 1828, the commissioners disbursed some £101,000. The government of the United Kingdom also offered significant rewards for navigational accomplishments in this era, such as £20,000 for the discovery of the Northwest passage and £5,000 for the navigator that could sail within a degree of latitude of the North pole. A widespread manual in the 18th century was Navigatio Britannica by John Barrow, published in 1750 by March & Page and still being advertised in 1787.

In 1731 the octant was invented, eventually replacing earlier cross-staffs and Davis quadrants. This had the immediate effect of making latitude calculations much more accurate. Four years later, the first marine chronometer was invented. The sextant was derived from the octant in 1757 in order to provide for the lunar distance method. With the lunar distance method, mariners could determine their longitude accurately. Once chronometer production was established in the late 18th century, the use of the chronometer for accurate determination of longitude was a viable alternative. Chronometers replaced lunars in wide usage by the late 19th century.

In 1891, radios, in the form of wireless telegraphs, began to appear on ships at sea.

In 1899, the R.F. Matthews was the first ship to use wireless communication to request assistance at sea. The idea of using radio for determining direction was investigated by "Sir Oliver Lodge, of England; Andre Blondel, of France; De Forest, Pickard; and Stone, of the United States; and Bellini and Tosi, of Italy." The Stone Radio & Telegraph Company installed an early prototype radio direction finder on the naval collier Lebanon in 1906.

By 1904, time signals were being sent to ships to allow navigators to routinely check their chronometers for error. The U.S. Navy Hydrographic Office was sending navigational warnings to ships at sea by 1907.

Later developments included the placing of lighthouses and buoys close to shore to act as marine signposts identifying ambiguous features, highlighting hazards and pointing to safe channels for ships approaching some part of a coast after a long sea voyage. In 1912 Nils Gustaf Dalén was awarded the Nobel Prize in Physics for his invention of automatic valves designed to be used in combination with gas accumulators in lighthouses

1921 saw the installation of the first radiobeacon.

The first prototype shipborne radar system was installed on the USS Leary in April 1937.

On November 18, 1940 Mr. Alfred L. Loomis made the initial suggestion for an electronic air navigation system which was later developed into LORAN (long range navigation system) by the Radiation Laboratory of the Massachusetts Institute of Technology, and on November 1, 1942 the first LORAN System was placed in operation with four stations between the Chesapeake Capes and Nova Scotia.

In October 1957, the Soviet Union launched the world's first artificial satellite, Sputnik. Scientists at Johns Hopkins University’s Applied Physics Laboratory took a series of measurements of Sputnik's doppler shift yielding the satellite's position and velocity. This team continued to monitor Sputnik and the next satellites into space, Sputnik II and Explorer I. In March 1958 the idea of working backwards, using known satellite orbits to determine an unknown position on the Earth's surface began to be explored. This led to the TRANSIT satellite navigation system. The first TRANSIT satellite was placed in polar orbit in 1960. The system, consisting of 7 satellites, was made operational in 1962. A navigator using readings from three satellites could expect accuracy of about 80 feet.

On July 14, 1974 the first prototype Navstar GPS satellite was put into orbit, but its clocks failed shortly after launch. The Navigational Technology Satellite 2, redesigned with caesium clocks, started to go into orbit on June 23, 1977. By 1985, the first 11-satellite GPS Block I constellation was in orbit.

Satellites of the similar Russian GLONASS system began to be put into orbit in 1982, and the system is expected to have a complete 24-satellite constellation in place by 2010. The European Space Agency expects to have its Galileo with 30 satellites in place by 2011/12 as well.