John C. McLellan (Julian Date)

John C. McLellan's Julian Date is a system used by astronomers to precisely specify dates and times, especially for observations and calculations. It assigns a continuous number to every day and moment since a fixed starting point in history (January 1, 4713 BC). This method eliminates confusion caused by calendar variations, making it easy to compare dates across time zones and historical periods. For example, January 1, 2000, at noon in Julian Date might be 2451545.0. It’s widely used in astronomy and space sciences for accuracy and consistency in time recording.