what is the 180 degree line of longitude called
180th meridian or antimeridian 180th meridian antimeridian
title: 180th meridian text: 180th meridian The 180th meridian or antimeridian is the meridian 180° both east and west of the Prime Meridian, with which it forms a great circle dividing the earth into the Western and Eastern Hemispheres. It is common to both east longitude and west longitude. It mostly passes through the open waters of the Pacific Ocean, but passes across land in Russia, Fiji and Antarctica. This meridian is used as the basis for the International Date Line, but the latter deviates from it to maintain date consistency within the territories of Russia, USA, Kiribati, Fiji and New Zealand. Starting at title: Longitude text: Longitude Longitude (, ), is a geographic coordinate that specifies the east–west position of a point on the Earth's surface. It is an angular measurement, usually expressed in degrees and denoted by the Greek letter lambda (λ). Meridians (lines running from pole to pole) connect points with the same longitude. By convention, one of these, the Prime Meridian, which passes through the Royal Observatory, Greenwich, England, was allocated the position of 0° longitude. The longitude of other places is measured as the angle east or west from the Prime Meridian, ranging from 0° at the Prime Meridian to +180° eastward title: 90th meridian east text: 90th meridian east The meridian 90° east of Greenwich is a line of longitude that extends from the North Pole across the Arctic Ocean, Asia, the Indian Ocean, the Southern Ocean, and Antarctica to the South Pole. It is the border between two tropical cyclone basins: the Australian region, and the Southwest Indian Ocean basin. The Ninety East Ridge is named after the meridian. The 90th meridian east forms a great circle with the 90th meridian west. This meridian is halfway between the Prime meridian and the 180th meridian and the center of the Eastern Hemisphere is on this meridian. title: Meridian (geography) text: side of the earth from Greenwich, the antimeridian, forms the other half of a circle with the one through Greenwich, and is at 180° longitude near the International Date Line (with land mass and island deviations for boundary reasons). The meridians from West of Greenwich (0°) to the antimeridian (180°) define the Western Hemisphere and the meridians from East of Greenwich (0°) to the antimeridian (180°) define the Eastern Hemisphere. Most maps show the lines of longitude. The position of the prime meridian has changed a few times throughout history, mainly due to the transit observatory being built next door title: ISO 6709 text: Longitude is a number preceded by a sign character. A plus sign (codice_2) denotes east longitude or the prime meridian, and a minus sign (codice_3) denotes west longitude or 180° meridian (opposite of the prime meridian). Rules about the number of digits are the same as for latitude. The CRS identifier begins with "CRS". There are three styles: The example of original Annex H always use "CRSWGS_84". ISO 6709 ISO 6709 "Standard representation of geographic point location by coordinates" is the international standard for representation of latitude, longitude and altitude for geographic point locations. The first edition (ISO 6709:1983) was