Time standard
The Leap Second
The extra second occasionally inserted into Coordinated Universal Time to keep it within 0.9 seconds of UT1, so that civil clocks stay in step with the turning of the Earth. As atomic time and Earth rotation drift apart, leap seconds bridge the gap — a practice now being reconsidered.
Highlights
- ›Keeping the clock in step with the spinning Earth
Bodies, frames & concepts
Knowledge connections
- Associated withCoordinated Universal Time (UTC)
- Associated withUniversal Time (UT1)
- Associated withInternational Earth Rotation and Reference Systems Service (IERS)
Sources
The primary and reference sources this topic draws on.
- US Naval ObservatoryUnited States Naval Observatory
Precise time, almanac data, Sun/Moon rise-set, and phases.