The 'leap second' could disappear. How a minor time adjustment became a major problem
International timekeeping authorities have voted to discontinue the use of 'leap seconds' to correct the discrepancy between atomic time and Earth's rotation. This change aims to simplify global timekeeping systems, though it will eventually lead to a drift between solar and atomic time.
Why it matters
Leap seconds have historically caused technical issues for digital infrastructure; removing them will improve stability for global computing systems.
On Thursday, an international timekeeping body in France voted to do away with leap seconds and let the clocks slip until they're out of alignment by a full hour, which could take centuries or even millennia.
The precise atomic time we use to track our days — developed in the 1950s and measured by tracking the natural vibrations of atoms — is slightly out of sync with solar time, which is based on the position of the sun in the sky relative to a specific location on Earth, because the planet's rotation has been gradually slowing.
The leap second was introduced in 1972 as a way to correct the discrepancy. Ten seconds were added immediately, says Scott Beattie, lead of the frequency and time team at the National Research Council of Canada's Metrology Research Centre.
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