Our Workdays are Getting Longer?!
We all know about our 24-hour days concept, but did you know they can get longer and shorter as time goes on? Science shows that our days have been getting longer, and that there have been reports of some days in the past being a lot shorter than what we have now! A T-Rex from 70 million years ago would’ve experienced days that were 23 ½ hours long.
There are many theories of why our day’s length may be longer or shorter than 24 hours every day, one of them being the position of the moon. As time goes on, the moon starts drifting further away from its usual path around Earth, known as the elliptical orbit. Since the moon is what controls our tidal currents, the heat created by them reduces when the moon drifts further away, and our planet begins to slow its spinning. According to the New York Times, “The moon’s gravitational tug is responsible for tidal changes on Earth. Tidal currents heat the ocean very slightly, dissipating energy, which slows the rotation of Earth and lets the moon move farther away as time passes.” This proves that as the Earth slows due to the tidal current’s heat, the moon drifts further away every time and repeats the process.
Another reason Earth’s constant spin is slowing down could be because of climate change. As the Earth gets warmer, icebergs begin to melt. This excess water recedes from the poles and heads towards the equator (middle “line” of the earth), causing our planet to become more oblate. According to the New York Times, as the water moves towards the equator, the spinning slows like a spinning ice skater, who spins faster as their arms are pulled close. This shows that extra water on the sides of our planet causes the Earth to slow and our days to become seemingly longer.
For as long as humans could measure it, the length of our days has never been steady for centuries. There have been a lot of slow periods in the 1990s and the 1970s, where the days drag on for 2 seconds past the 24-hour mark. “It’s an extremely difficult problem to untangle the different contributing factors,” said Surendra Adhikari, a geophysicist at NASA’s Jet Propulsion Laboratory. Since there are multiple factors that can contribute to the slowing down and speeding up of our days, it is hard to guarantee when these changes will happen.
To conclude, a day on Earth will usually be around 24 hours, but as the moon drifts further away and other small factors affect the spin of our planet, there is always a chance that 24 hours can go up to 25, or down to 23 someday. The Earth is very large and complex, while the factors measured to determine the day are very small, and we can only study so much about it at a steady pace. However, these changes are often very small and take billions of days to happen, so it’s not likely you will notice them.
