The 24-hour day is not fixed but slowly stretching, and in the dinosaurs' time it was shorter: the Moon's pull is gently braking Earth's spin, so a day back then ran about 23.5 hours, and far shorter
Earth's rotation is gradually slowing down due to the Moon's gravitational pull, causing days to lengthen by approximately 1.8 milliseconds per century. This long-term process is influenced by tidal friction and geological shifts, meaning the length of a day is not a fixed constant.
Why it matters
Understanding the mechanics of Earth's rotation is essential for precise timekeeping and geological history, highlighting how planetary interactions shape our fundamental perception of time.
The Moon is slowly stealing Earth's rotational energy, making each day microscopically longer—a process that has been stretching time since the planet's formation and will continue long after humans are gone.
The day you are living through right now is longer than any day a dinosaur ever saw. Not by much, and not in a way you could feel, but the number is real and it keeps climbing.
Nearly 3,000 years of eclipse and astronomical records show that Earth’s average length of day has increased by about 1.8 milliseconds per century. The tides that the Moon and Sun raise in our oceans are slowing us down.
Tiny over a lifetime. Enormous across the age of the planet.
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