If the days seem to get shorter as you get older, you can’t imagine it.
On June 29, 2022, Earth made one complete rotation that took 86,400 seconds, or 1.59 milliseconds less than the average day length of 24 hours. While a 1.59 millisecond shortening may not seem like much, it’s part of a larger and weirder trend.
In fact, on July 26, 2022, there was another new record almost Set when Earth ended its day 1.50 milliseconds slower than normal, as reported guardian and time-tracking websites time and date. Time and Date notes that 2020 is the shortest day since scientists began using atomic clocks to take daily measurements in the 1960s. Scientists first began noticing the trend in 2016.
Although the length of an average day may vary little in the short term, the length of the day in the long term has been increasing since the formation of the Earth-Moon system. Because over time, gravity has transferred energy from Earth — via tides — to the Moon, pushing it slightly away from us. Meanwhile, since the two bodies are in tidal lock—meaning the Moon’s rotation and revolution rate are the same that we ever see one side of it—physics dictates that Earth’s days must be longer if the two bodies are in tidal lock. As the moon moves away. Billions of years ago, the moon was much closer and Earth’s days were much shorter.
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While scientists know Earth’s days are getting shorter on a short-term scale, a precise reason why remains unclear — including the implications it may have on how we as humans track time.
“The rotation rate of the Earth is a complicated business. It has to do with the exchange of angular momentum between the Earth and the atmosphere and the influence of the oceans and the influence of the Moon,” said Judah Levin, a physicist in the Department of Time and Frequency. National Institute of Standards and Technology, told Discover magazine. “You’re not able to predict what’s going to happen in the future.”
But Fred Watson, Australia’s astronomer-at-large, told Australia’s ABC News If nothing is done to stop it, “you’re slowly moving the seasons out of step with the calendar.”
“When you start looking at the real nitty gritty, you realize the world isn’t just a solid ball that’s spinning,” Watson said. “It’s got liquid inside, it’s got liquid on the outside, and it’s got an atmosphere and all these things are slowing down a bit.”
Matt King of the University of Tasmania told ABC News Australia the trend was “definitely strange”.
“Clearly something has changed, and changed in a way that we haven’t seen since the beginning of precise radio astronomy in the 1970s,” King said.
Could it be related to extreme weather patterns? As reported by guardianNASA reports that Earth’s rotation can slow down strong winds El Nino years and can Slow down the rotation of the planet. Similarly, melting ice caps cause material to move around the Earth and thus change the rate of rotation.
Although this minor time-suck has little effect on our daily lives, some scientists have called for the introduction of a negative “leap second”, which would subtract one second from a day to keep the world on track for atomic time, if the trend continues. Since 1972, leap seconds have been added every few years. The last one was added in 2016.
“If the Earth’s rotation rate were to increase further, a negative leap second would be required, but it is too early to say whether this could happen,” said Peter Wibberley, a physicist at the UK’s National Physics Laboratory. telegraph. “There is also international discussion about the future of the leap second, and it is possible that the need for a negative leap second could push the decision to end the leap second for good.”