The duration of an Earth’s day is 24h (give or take a couple of minutes), right?
Or is it?
Well, not no more. If scientific predictions are to be believed, a 25h-long day will become a reality in about 200 million years.
This is because Earth’s orbit around the Sun slows down over time. It’s a very gradual process that takes millions of years. On average, the duration of one day on Earth increases by about two milliseconds every hundred years.
So if the Earth still exists in 2,000,000 centuries, well, contemporary folks will have an extra hour to play with, and clock makers will have to figure out ways to cram in another digit somehow.