Length of the semimajor axis of Earth's orbit around the Sun, 92,955,808 mi (149,597,870 km), often defined simply as the average distance from Earth to the Sun. Direct measurement through the parallax method cannot be used for accurate determinations, because the Sun's glare blots out the light of the background stars necessary to make the measurement. The most precise values have been obtained by measuring the distance from Earth to other objects orbiting the Sun. This indirect method requires an accurate proportional mathematical model of the solar system; once the distance to one planet or other object is determined, then the distance to the Sun can be calculated.

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City (metro. area pop., 1997: 1,556,000), seaport, and capital of Haiti, West Indies, on the southeastern shore of the Golfe de la Gonâve. Founded by the French in 1749, it was destroyed by earthquakes in 1751 and 1770 and has frequently suffered from fires and civil strife. In 1807 the port was opened to foreign commerce. It is the country's principal port and commercial centre, producing sugar, flour, cottonseed oil, and textiles.

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Monetary system in which the standard unit of currency is a fixed quantity of gold or is freely convertible into gold at a fixed price. The gold standard was first adopted in Britain in 1821. Germany, France, and the U.S. instituted it in the 1870s, prompted by North American gold strikes that increased the supply of gold. The gold standard ended with the outbreak of World War I in 1914; it was reestablished in 1928, but because of the relative scarcity of gold, most nations adopted a gold-exchange standard, supplementing their gold reserves with currencies (U.S. dollars and British pounds) convertible into gold at a stable rate of exchange. Though the gold-exchange standard collapsed during the Great Depression, the U.S. set a minimum dollar price for gold, an action that allowed for the restoration of an international gold standard after World War II. In 1971 dwindling gold reserves and an unfavourable balance of payments led the U.S. to suspend the free convertibility of dollars into gold, and the gold standard was abandoned. Seealso bimetallism; exchange rate; silver standard.

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Rapid influx of fortune seekers to the site of newly discovered gold deposits. In North America, the first major gold strike occurred in California in 1848, when John Marshall, a carpenter building a sawmill for John Sutter, found gold. Within a year about 80,000 “forty-niners” (as the fortune seekers of 1849 were called) had flocked to the California gold fields, and 250,000 had arrived by 1853. Some mining camps grew into permanent settlements, and the demand for food, housing, and supplies propelled the new state's economy. As gold became more difficult to extract, companies and mechanical mining methods replaced individual prospectors. Smaller gold rushes occurred throughout the second half of the 19th century in Colorado, Nevada, Idaho, Montana, South Dakota, Arizona, and Alaska, resulting in the rapid settlement of many areas; where gold veins proved small, the settlements later became ghost towns. Major gold rushes also occurred in Australia (1851), South Africa (1886), and Canada (1896). Seealso Klondike gold rush.

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Fund of gold bullion or coin held by a government or bank. In the past, banks accumulated gold reserves to fulfill their promise to pay their depositors in gold. Commercial banks received deposits subject to repayment in gold on demand and issued notes redeemable in gold on demand. Most gold reserves eventually shifted to central banks, which took over the function of issuing paper money. Gold reserves were moved again in the 1930s, when many governments required their central banks to turn over to the national treasuries all or most of their gold holdings. In the U.S., the Gold Reserve Act of 1934 required Federal Reserve banks to turn over all gold bullion or coin to the U.S. Treasury, which placed most of the reserves at Fort Knox.

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Metallic chemical element, one of the transition elements, chemical symbol Au, atomic number 79. It is a dense, lustrous, yellow, malleable precious metal, so durable that it is virtually indestructible, often found uncombined in nature. Jewelry and other decorative objects have been crafted from gold for thousands of years. It has been used for coins, to back paper currencies, and as a reserve asset. Gold is widely distributed in all igneous rocks, usually pure but in low concentrations; its recovery from ores and deposits has been a major preoccupation since ancient times (see cyanide process). The world's gold supply has seen three great leaps, with Christopher Columbus's arrival in the Americas in 1492, with discoveries in California (see gold rush) and Australia (1850–75), and discoveries in Alaska, Yukon (see Klondike), and South Africa (1890–1915). Pure gold is too soft for prolonged handling; it is usually used in alloys with silver, copper, and other metals. In addition to being used in jewelry and as currency, gold is used in electrical contacts and circuits, as a reflective layer in space applications and on building windows, and in filling and replacing teeth. Dental alloys are about 75percnt gold, 10percnt silver. In jewelry, its purity is expressed in 24ths, or karats: 24-karat is pure, 12-karat is 50percnt gold, etc. Its compounds, in which it has valence 1 or 3, are used mainly in plating and other decorative processes; a soluble chloride compound has been used to treat rheumatoid arthritis.

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(born March 6, 1885, Niles, Mich., U.S.—died Sept. 25, 1933, East Hampton, N.Y.) U.S. writer. He worked as a newspaper reporter, sportswriter, and columnist before he began publishing fiction. He won popular success with comic stories about a baseball player, some collected in You Know Me, Al (1916). Later collections, noted for their satire, narrative skill, and convincing vernacular language, include How to Write Short Stories (1924) and The Love Nest (1926). His son, the screenwriter Ring Lardner, Jr., was one of the Hollywood Ten and later wrote such hit movies as M*A*S*H (1970).

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Section of the coast of the Gulf of Guinea, western Africa. Extending approximately from Axim, Ghana, in the west to the Volta River in the east, it was so called because it was an important source of gold. It was an area of intense colonial rivalry from the 17th century. Acquired as a colony by the British in the 19th century and named the Gold Coast, the area achieved independence as the Republic of Ghana in 1957.

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African intergovernmental organization. It is the successor to the Organization of African Unity (OAU). The AU was established in 2002 to promote unity and solidarity among African states, spur economic development, and promote international cooperation. The OAU was established in 1963 with similar goals, and during its tenure the group mediated several border disputes on the African continent. More economic in nature and with a stronger mandate to intervene in conflicts, the AU replaced the OAU in 2002. In 2004 the AU's Pan-African Parliament was inaugurated, and the organization agreed to create a peacekeeping force. The AU's headquarters are in Addis Ababa, Eth.

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