Earth is spinning slightly faster since 2020, shortening days by milliseconds. Scientists say we may need to subtract a leap second from clocks by 2029 — a first. The cause remains unclear, though internal Earth changes are suspected. Scientists reassure there’s no danger.

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• Earth spinning faster since 2020; shortening day length by fractions of a second
• Days getting shorter — may need to remove 1 leap second from timekeeping by 2029
• Would be 1st time a leap second is removed, not added
• Earth’s full spin usually takes ~86,400 seconds, but minor changes occur naturally
• Spin speed influenced by tides, earthquakes, volcanic shifts, internal Earth changes
• Recent changes too fast for models to fully explain
• Shortest days in 2025 expected on July 9, July 22, August 5
• August 5 may be 1.51 milliseconds shorter than a 24-hour day
• Scientists suspect Earth’s core changes; surface or atmospheric shifts too weak
• No impact on daily life; long-term slowing trend still intact