‘Shortest day of 2026’: How this 'milli-seconds shift' is threatening GPS and satellites
Scientists report that Earth's rotation is fluctuating, resulting in the shortest day of 2026 on July 26, a phenomenon linked to climate change and mass distribution shifts. While the millisecond-level change is imperceptible to humans, it poses long-term challenges for GPS, satellite navigation, and global timekeeping systems.
Why it matters
It underscores how climate-driven environmental changes can have subtle but critical impacts on the precision-dependent infrastructure of modern global technology.
This Sunday, July 26, will be the shortest day of 2026. However, the difference is so tiny – just 0.65 milliseconds – that no one will notice. This time is less than the blink of an eye, less than the time it takes a camera flash to fire, and life will carry on entirely undisturbed. But behind that ‘flicker of time’ lies a story that scientists say should concern all of us. The Earth's rotation is altering in ways that are unmatched in at least 3.6 million years, and climate change is the reason.What is actually happening on July 26According to the International Earth Rotation and Reference Systems Service (IERS), the organisation responsible for keeping global time, Sunday's day will measure approximately 0.65 milliseconds shorter than the standard 24 hours, or 86,400 seconds. That makes it the shortest day of the year so far.
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