Due to the speeding up of the planet, a negative second may soon be needed so atomic clocks can align correctly with the turning world.
The planet is completing its rotation in 1.4602 milliseconds less than the usual 86,400 seconds. The complex motion of the earth’s molten interior, ocean, atmosphere, and celestial bodies—like the Moon—have an effect on the earth’s rotation. The friction of the tides and the change in distance between the Earth and the Moon also lead to daily variation of the speed of the planet’s axial rotation.
July 19th, 2020 was recorded as the shortest day since recording started in the 1960s owing to the development of atomic clocks. The previous shortest day in 2005, was beaten 28 times in 2020. 2021 is expected to be the fastest ever by 0.5 milliseconds.
“It is certainly correct that the Earth is spinning faster now than at any time in the last 50 years,” Peter Whibberley, a senior research scientist with National Physical Laboratory’s time and frequency group, told The Telegraph, adding that “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.”
“There are also international discussions taking place about the future of leap seconds, and it’s also possible that the need for a negative leap second might push the decision towards ending leap seconds for good.”
It would take hundreds of years for the difference to become obvious to most people; however, modern satellite communication and systems rely on time being consistent with the conventional positions of the Sun, Moon, and stars.
It is the responsibility of scientists and officials at the International Earth Rotation Service in Paris, to monitor the planet’s rotation and inform countries when leap seconds must be added or taken away six months in advance.
ARTICLE: EJAZ SHAIKH
PHOTO CREDITS: THE SCOTSMAN