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Earth's Day Shortens Again: 1.34 Milliseconds Faster!

7/22/2025

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Summary

Story summary

On July 22, 2025, Earth will spin through one of its briefest days, finishing its rotation 1.34 milliseconds quicker than the usual 24 hours. This phenomenon has been ongoing for five years, with the record shortest day clocking in at 1.66 milliseconds faster on July 5, 2024. Scientists warn we might face a negative leap second by 2029.

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Story summary

On July 22, 2025, Earth will spin through one of its briefest days, finishing its rotation 1.34 milliseconds quicker than the usual 24 hours. This phenomenon has been ongoing for five years, with the record shortest day clocking in at 1.66 milliseconds faster on July 5, 2024. Scientists warn we might face a negative leap second by 2029.