The Earth is spinning faster and faster: a negative leap second might be the answer

The moon is actually holding back the Earth, rotating a little slower. But researchers now report that 2020 was the shortest day on record – and another 27 days were very fast.

The movements of the celestial bodies in the solar system determine the pace of life at Land Before. at 24 hours Turns th Land Once around – the day lasts 24 hours. 365 days Does it take up Land Once in Sun It has been around – this is a duration of one day. But the system of movements of the celestial bodies and our age is not quite as accurate as it seems: the Earth needs exactly 365 days, five hours, 48 ​​minutes, and 46 seconds to orbit the sun. In order to compensate for this inaccuracy and prevent Calendar Too much, a leap day is added to the calendar roughly every four years.

Earth’s rotation acceleration: 28 days in 2020 was very short

There is something similar to them Length of the day: One Earth’s rotation It does not always take exactly 24 hours (86,400 seconds). The interaction between the moon and the Earth, as well as earthquakes, weather conditions, or movements in the Earth’s core can lengthen or shorten the length of the day slightly. Until 2016 slouch Through these effects a little slower, somewhere through my accident Leap second It was balanced. But since then it wasn’t necessary to make a leap second: The Earth rotates a little faster.

Earth spins faster: Astronomer: Inside measures the length of the day

This is evidenced by the measurements taken by astronomers targeting specific points in the sky and measuring their length Earth’s rotation Endure. these The length of the sidereal day It comes with exactly Atomic clocks Comparison. Experts found that Earth exists 2020 Apparently spun especially quickly. On 28 days in 2020 The length of the day measured Shorter than the previous record on July 5, 2005. At that time, the day was 1.0516 milliseconds shorter than the 86,400 seconds that formed Logo card Official exists.

Faster Earth Rotation: New Record – It was the shortest day in 2020

Well there is one A new recordJul 19, 2020 It was 1.46ms shorter than the 86,400 seconds that today theoretically consists. Another 27 days in 2020 were also very short, according to the International Service of Earth Rotation and Reference Systems (IERS). IERS, which has its central office Frankfurt Falls is responsible for slouch For measurement and calculation. It also announces half a year in advance whether it is a file Leap second It should be included in a file Earth’s rotation fluctuations Balance.

For the next possible date, June 30, 2021, IERS has already announced It does not enter a leap second. Since the introduction of this system in 1972, 27 Positive leap seconds It was entered – but so far there hasn’t been one Negative leap seconds.

Fluctuations in the Earth’s rotation can make negative leap seconds necessary

That could change: the experts at IERS assume the Land It should be a little faster in 2021. It is estimated that in the current year, the average day could be 0.05 milliseconds shorter than 86,400 seconds. Over a year, this adds up to about 19 milliseconds – and it could happen someday Negative leap seconds Make it necessary.

Earth’s rotation fluctuation: 70 million years ago the day was 30 minutes shorter

The Earth’s rotation fluctuations They are minimal and absolutely not identifiable to humans without measurements. But a look at the past shows the effects that could arise over very long periods of time: 70 million years ago – around the time of the dinosaur era – it was turning around. Land Much faster than today. a Logo card Then it comprises of 23 hours, 31 minutes and one Public Consists of 372 days.

This is the main reason why the Earth has rotated slower since then Interaction between Earth and Moon: The moon is slowing you down Earth’s rotation from. This speeds itself up and moves a little further off the ground every year. why is that slouch Something suddenly changes in 2020 accelerated It’s not completely clear yet. There are doubts that this phenomenon could be linked to climate change, among other things. (Tania Banner)