A prime meridian is a meridian, i.e. a line of longitude, at which longitude is defined to be 0°. A prime meridian and its opposite in a 360°-system, the 180th meridian (at 180° longitude), form a great circle.

This great circle divides the sphere, e.g. the Earth, into two hemispheres. If one uses directions of East and West from a defined prime meridian, then they can be called Eastern Hemisphere and Western Hemisphere.

An international conference in 1884 decided the Prime Meridian passes through the Royal Observatory, Greenwich in southeast London, United Kingdom, known as the International Meridian or Greenwich meridian.

As of 2012 the most used prime meridian for the Earth is the IERS Reference Meridian (IRM). It passes 5.31 arcseconds east of Airy's transit circle or 102.5 metres (336.3 feet) at the latitude of the Royal Observatory, Greenwich, London. A current convention on the earth uses the opposite of the IRM as the basis for the International Date Line.

The modern Greenwich meridian, based at the Royal Observatory, Greenwich, was established by Sir George Airy in 1851. By 1884, over two-thirds of all ships and tonnage used it as the reference meridian on their maps. In October of that year, at the behest of U.S. President Chester A. Arthur, 41 delegates from 25 nations met in Washington, D.C., for the International Meridian Conference. This conference selected the Greenwich meridian as the official Prime meridian due to its popularity. However, France abstained from the vote and French maps continued to use the Paris meridian for several decades.

Charlie Hunter (born May 23, 1967) is an American guitarist, composer and bandleader.

First coming to prominence in the early 1990s, Hunter has recorded 17 albums. Hunter plays custom-made seven and eight-string guitars, on which he simultaneously plays basslines, rhythm guitar, and solos. Critic Sean Westergaard describes Hunter's guitar technique as "mind-boggling ... he's an agile improviser with an ear for great tone, and always has excellent players alongside him in order to make great music, not to show off."

Hunter was born in Rhode Island. When he was four his mom packed him and his younger sister in an old yellow school bus and headed west. After several years living on a commune in Mendocino County they settled in Berkeley, California. Hunter graduated from Berkeley High School and took lessons from famed guitar teacher Joe Satriani. At eighteen he moved to Paris. Returning to the Bay area, Hunter played a seven-string guitar and organ in Michael Franti's political rap group, The Disposable Heroes of Hiphoprisy. In 1992, they were one of the opening acts for U2's Zoo TV Tour.

Robert "Bobby" Previte (born July 16, 1951, Niagara Falls, New York) is a drummer, composer and bandleader. Previte earned a B.A. in Economics at the University at Buffalo, where he also studied percussion. He moved to New York City in 1979, and became active in the city's thriving jazz and experimental music scenes. He began professional relationships with John Zorn, Wayne Horvitz, Elliott Sharp and others that have continued, intermittently, to the present.

While Previte is a talented drummer he has also received critical acclaim for his "exceptional abilities as a composer and orchestrator." A review of his 1988 album Claude's Late Morning reports that "Perhaps most striking is Previte's skill in composing music that fully integrates these disparate instruments — including drums and drum machine, electric guitar and keyboards, trombone, harp, accordion, banjo, pedal steel guitar, tuba, and harmonica — while emphasizing each instrument's unique, individual sound." Another critic notes Previte's "driving and propulsive compositions, featuring both fiery jazz expressionism and layered counterpoint that suggested elements of contemporary minimalism.