Humanism in the age of Henry VIII. London ; Dover, N.H. : Croom Helm, 1986 (OCoLC)795302915: Named Person: Henry, King of England; Henry, King of England; Henry, King of England: Document Type: Book: All Authors / Contributors: Maria Dowling
Prior to 1972, this time was called Greenwich Mean Time (GMT) but is now referred to as Coordinated Universal Time or Universal Time Coordinated (UTC). It is a coordinated time scale, maintained by the Bureau International des Poids et Mesures (BIPM). It is also known as Z time or Zulu Time.
Although many time zones have descriptive names used by people in them, they are least ambiguously identified by their relationship to UTC (Universal Time, Co-ordinated). UTC used to be called GMT (Greenwich Mean Time), after the Royal Observatory located in the Greenwich area of London. UTC is also sometimes called Z or Zulu time. A time may be written as e.g. 21:45Z with the Z indicating UTC. The Z is for zero, and Zulu is the two-way radio pronunciation of Z. It comes from the nautical system in which each time zone was assigned a letter.