The Earth is now spinning faster than it was 50 years ago.. Scientists reveal!

Amman Today

publish date 2021-12-23 09:52:25

The Earth is spinning faster than it did half a century ago, and if it continues to accelerate, scientists say they may have to remove one second from the atomic clock.

The speed of our planet’s rotation on its axis has varied throughout history. In fact, the Earth rotated 420 times a year millions of years ago, but now it does so 365 times.

However, sometimes the speed of rotation varies slightly, which affects the global timekeeper – the atomic clock – which requires the addition of leap seconds when the world is moving a little faster.

Now, British National Physical Laboratory scientist Peter Webberley has warned that if the rate of rotation increases further, a negative leap second may be needed.

Each day on Earth contains 86,400 seconds, but the rotation is not uniform, which means that over the course of a year, each day contains a fraction of a second more or less.

This occurs due to the movement of the Earth’s core, its oceans and atmosphere, as well as the clouds of the Moon. The atomic clock is extremely accurate, and measures time by the movement of electrons in atoms that have been cooled to absolute zero. So, to keep the atomic clock in line with the number of seconds in the Earth’s rotation, leap seconds have been added every 18 months or so since 1972.

There was no negative leap second—the removal of one second from the atomic clock—and the system designed to do the work had not been tested.

The idea arose last year, when the rotation began to accelerate, but that has slowed again since then, with the average day in 2021 being 0.39ms lower than in 2020.

Judah Levine, of the National Institute of Standards and Technology, told Discover magazine: “With time, there is a gradual difference between the time of atomic clocks and the time measured by astronomy. In order to prevent this difference from becoming too large, in 1972, a decision was made to add the seconds. leap periodically into atomic clocks.

The International Earth Rotation and Reference Systems Service, which is responsible for tracking the speed of the Earth’s rotation, does this by sending laser beams to satellites and using them to measure their movement.

And when that doesn’t align with atomic clocks, scientists coordinate to stop their clocks for one second to get them back on line.

The rate of Earth’s rotation is a complex business. It’s about the exchange of angular momentum between Earth and the atmosphere, ocean effects, and the moon’s influence, Levine explained.

No leap second has been added to the atomic clock since 2016, and as the Earth was accelerating again, it began decelerating again in 2021.

“This decrease in the need for leap seconds was unexpected,” Levine said. He added that the Earth was supposed to continue to slow down, “so this effect is very surprising.”

How long it will take to slow down may require scientists to take more action, but it’s still not clear what that might be.

“There is a concern right now that if the Earth’s rotation rate increases further, we may need a so-called negative leap second,” Webberley said.

In other words, instead of introducing an extra second to allow the Earth to catch up, we have to take a second off the atomic timescale to bring it back to its state with Earth.

And while they know how to make it work, scientists aren’t clear if their systems will actually work, or what effect they will have.

The Internet relies on a continuous flow of time, which is measured by atomic clocks, and different web companies use different processes to determine leap seconds.

For example, Google uses a system that allocates extra time throughout the year, to every other second of the year.

“The basic backbone of the Internet is that time goes on,” Levin explained. He added that when there is no fixed time, the continuous feed of information breaks down.

Levine says the leap seconds – added or removed – may not be worth the trouble, as they would add up to only about one minute over 100 years.

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