Leap seconds have helped keep clocks synchronized with Earth’s rotation, but their time may be over - here’s why
International timekeeping organizations are considering ending the use of leap seconds to synchronize clocks with Earth's rotation. This shift reflects the move toward more precise, atomic-based timekeeping systems that no longer rely on the planet's irregular rotation.
Why it matters
Leap seconds are critical for global digital infrastructure, and their removal could have significant implications for software systems and scientific research that rely on precise time synchronization.
Humans haven’t always counted time down to the second. mrs/Moment via Getty Images Leap seconds have helped keep clocks synchronized with Earth’s rotation, but their time may be over – here’s why Published: October 8, 2026 1.11pm BST https://theconversation.com/leap-seconds-have-helped-keep-clocks-synchronized-with-earths-rotation-but-their-time-may-be-over-heres-why-291017 https://theconversation.com/leap-seconds-have-helped-keep-clocks-synchronized-with-earths-rotation-but-their-time-may-be-over-heres-why-291017 Link copied Share article Share article
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You’re probably used to the month of February having an extra day every four years, during the leap year . Timekeepers added that extra leap day because Earth completes one orbit around the Sun in about 365 and one-quarter days. If we didn’t add leap days, the equinoxes and solstices that mark the beginning of seasons would occur later, slowly shifting the days on which each season began.
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