Earth’s Unusual Rapid Spin Could Prompt First-Ever ‘Negative Leap Second’
The Earth has been spinning unusually fast recently. Last year on July 4, our planet set a record by completing a full spin 1.66 milliseconds (0.00166 seconds) faster than usual, according to timeanddate.com. One year later, on July 10, 2025, Earth completed a daily rotation that scientists estimate was 1.36 milliseconds faster than usual, giving us another particularly short day. Other shorter (but ever-so-slightly longer) days occurred on July 9 and July 22, although the exact margins have yet