Example image of eyePlorer eyePlorer map for 'Royal Observatory, Greenwich': 1675 August 10 Charles II of England Cornerstone Greenwich Greenwich Park London River Thames Palace of Placentia Jonas Moore Christopher Wren Robert Hooke HM Nautical Almanac Office Time Thomas Tompion George Biddell Airy Longitude Meridian circle Prime Meridian 1999 December 16 Laser Datum (geodesy) Geoid Oblate spheroid Sea level International Terrestrial Reference System World Geodetic System Minute of arc Coordinated Universal Time Polar motion Universal Time John Pond Time ball British Summer Time Anarchism Joseph Conrad The Secret Agent John Harrison Marine chronometer National Maritime Museum Howard Grubb Refracting telescope Shepherd gate clock Planetarium 2007 May 25 Peter Harrison Planetarium Abinger Magnetism