1001 Space Earth Nature History First Civilisations Ancient Egypt Biblical Times Ancient Greece Ancient Rome Chinese, Japanese Civilisations Indian Civilisation African Civilisation The Early Americas The Rise of Islam The Middle Ages The Renaissance Civil War and Revolution The Industrial Revolution Two World Wars 20th-century Achievements Human World Science and Technology	What is the world's most accurate clock? The world's most accurate time keeper is an atomic clock that was produced in America in 1990. It is about the size of a desktop computer, and is accurate to 1 second in 1.6 million years. An atomic clock   Previous: Back Book: 1001 Section: History Chapter: 20th-century Achievements