Wednesday , February 24 2021

Do we need a ‘second drop’? Decades later the Earth is accelerating, causing anxiety



Do you have a second? Thought to slow down gradually, our planet has been spinning rapidly for 50 years. You need to know why.

Always accustomed to adding a “jump second”, in order to keep their atomic clocks accurate, international timekeepers are now wondering whether to add the “negative jump second” for the first time or the “second fall”.

The reason for this is the fastest rotation since we saw the shortest day last year – since people started counting. In fact, 2020 included the shortest 28 days since 1960.

So what happens? Why Is Is the Earth Rotating Fast? Does it matter?

The answer, as you guessed it, able Be evil – the Earth is spinning faster in space due to the melting of glaciers.

How fast does the earth rotate?

The Earth normally rotates around its axis at regular speeds of 86,400 seconds (1,440 minutes or 24 hours). It is one solar day, and we judge it by the apparent motion of the sun across the sky, which is clearly caused by the rotation of the earth.

However, our planet does not always work like clockwork. Our planet rotates more slowly.

By 2020, the Earth will have stopped slowing down and is now accelerating. Now a day is less than half a millisecond for 24 hours.

so what?

Why was 2020 a slow year for our planet?

According to the blogs of Graham Jones and Constantine Echoes, the record for the shortest rotation since 1973 was 1.0516 milliseconds in less than 24 hours on July 5, 2005. “In 2020, the earth is in a hurryFor TimeandDate.com.

“In mid-2020, the Earth beat that record no less than 28 times,” Jones writes. “The shortest day of all came on July 19, when the Earth’s rotation decreased from 1.4602 milliseconds to 86,400 seconds.”

Why does it matter how fast the earth rotates?

While it may not seem like much, over time it will have big consequences, because the atomic clocks used in GPS satellites do not take into account the changing rotation of the Earth.

If the Earth rotates rapidly, it will reach that point a little earlier. Half a millisecond equals 10 inches or 26 centimeters at the equator. In short, the GPS satellites that already need to be corrected for the effects of Einstein’s general theory of relativity (the curve of space and time) will soon be useless.

There are also confusing consequences for smartphones, computers and communication systems, which synchronize with the Network Time Protocol (NTP) servers. Defined as seconds from UTC 00:00:00 on January 1, 1970, standard Unix time is a “drop per second”, but is not designed to be successful with fast seconds. Like Be less problematic.

How eclipses help

Differences in the Earth’s rotation speed make it more difficult to estimate split-second events, such as eclipses.

In fact, Babylonian, Chinese, Arabic, and Greek astronomers report observations of solar eclipses, one way of finding out how fast the earth must have rotated in the past.

It is possible to predict the exact time of an eclipse in the future, but it is more difficult to predict exactly where it will occur.

Why Is Is the Earth Rotating Fast?

The rotation of the earth has indeed been slowing down for centuries. Now it is an exception.

The rotation of the earth may change slightly due to a number of factors. The pressure, seismic activity, and normal motions of our Earth’s inner core are a large factor, and it may rotate slightly faster than the planet as a whole.

Other seismic activities, such as earthquakes, also have a small effect on the atmosphere, weather, oceans, and the moon. The Earth’s rotation is gradually slowed down by its gravitational pull, causing a tidal wave, and the Earth’s orbit around the Sun is slightly elliptical.

However, according to one theory, it may be our fault that the Earth’s rotation is slow. According to some research, 20th century glacier melting has less weight on the rocks at the poles, causing it to rise higher and orbit the planet. Due to its effect it can rotate more quickly and its alignment can be slightly changed.

Why did the Earth stop in 2020?

So 2020 was an exception and the average day in most years will be a bit longer Another More than 24 hours. The International Earth Rotation and Surveillance Systems Service (IERS), which has been accustomed to a gradual slowdown since 1973, adds an extra jump per second to atomic clocks every two or three years. It last happened on December 31, 2016, June 30, 2015 and June 30, 2012.

(IERS tends to add (or theoretically reduce) fast seconds every June or December and announce its decision a few months in advance.)

So with the final addition of a second, some excess has built up, but in 2020 the Earth stopped. Its average daylight hours were exactly 24 hours. Throughout the year, it orbited the Sun at a speed of 1.28 milliseconds faster than normal.

So the IRS announced that it would not add a second leap next June. A second reduction is likely to be considered in the future and will be the first time for IERS.

Why the Earth is Faster in 2021

This is because the Earth is forecast to accelerate by 2021, with a deficit of 35.40 milliseconds by the end of the year.

The true length of the Earth’s rotation (known as UT1) is currently slightly behind Coordinating Universal Time (UTC), the standard used to keep time around the world (following the International Atomic Time (TAI)).

In 2021 we will have a delay of 19 milliseconds in atomic time, and if the recent rotation of the Earth continues, we will need something new on Earth from time to time. That means a day with 86,399 seconds.

Should atomic clocks add a second in a few years and then subtract UTC to keep them close to mid-sun time?

The rapidly rotating earth has consequences. In our age, the concept of making atomic clocks can be a complete waste of time.

A clear sky and wide eyes wish you well.


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