Earth is going to spin a little faster today, an estimated one-point-34 milliseconds quicker than the typical 24 hours. It'll create the second-fastest day in recorded history. But to be fair, records have only been kept since 1973. The shortest day was July 5th, 2024. The Earth's rotation experiences fluctuations due to a number of factors, including the moon's gravity, atmospheric changes and the behavior of the planet's liquid core. The former Director of Time at the United States Naval Observatory is amused by the attention this is getting. He notes "We've known about the rotation of the Earth being variable for about a hundred years. This is just one of those little variations that comes along."