WHAT’S BEING CLAIMED:
- When the earth’s rotation slows down, international timekeepers add a leap second to keep earth and solar time balanced.
- When it spins faster, a leap second is subtracted.
- In 2020, scientists recorded 28 shortest days, meaning the earth has been spinning fast.
According to International timekeepers, a ‘leap second’ is occasionally added to a year to make-up for the slowing down of the Earth’s rotation. If the Earth spins faster, a leap second would have to be subtracted or a negative leap second.
Adding ‘leap seconds’ is done to keep Earth in time with ‘solar time’ or the average length of day that is based on how long the Earth rotates.
In 2016, scientists added a leap second as the earth slowed down but in 2020, there have been 28 shortest days due to the Earth spinning faster than it has been for 50 years.
TimeandDate.com’s Graham Jones, said: “Before this year began, the shortest day since 1973 was July 5, 2005, when the Earth’s rotation took 1.0516 milliseconds less than 86,400 seconds.
“But in the middle of 2020, the Earth beat that record no less than 28 times. The shortest day of all came on July 19, when the Earth completed its rotation in 1.4602 milliseconds less than 86,400 seconds.”
According to Peter Whibberley of the National Physical Laboratory, due the earth spinning faster now, “It’s quite possible that a negative leap second will be needed if the Earth’s rotation rate increases further, but it’s too early to say if this is likely to happen.
This means that one year would be a second shorter than others.
The adding and subtracting are not noticeable as the atomic clocks which control our clocks on our phones and our pc automatically adjust themselves and go back to normal.
Worldwide, atomic clocks either ‘switch off’ for a second, or go to 23.59.60 before it would show 00.00.00.
Whibberley said that there have been international discussions on the future of leap seconds as the Earth’s rotation slows down and speeds up. Adding or subtracting leap seconds might just be eliminated.