by The moon forms earthly days of loan – Getty Images
IF They are the type of person who is done a lot, they are grateful for each of the 86,400 seconds that make up one day. On July 9th and on July 22nd and August 5th, they will not receive their full addition of seconds. These days, the earth can be measured – and has so far inexplicably accelerate its rotation and shaved from 1.3 to 1.5 milliseconds from the usual 24 hours when the typical day gets.
A millisecond or a thousandth of a second is admittedly not much – an Eyeblink takes about 100 milliseconds. But with atomic clocks that pursue the rotation speed of the earth so precisely, the international grounding and reference system service (yes, there is something like this) has to jump to the year to increase the speed of the planet, every millisecond. So what is behind the sudden speed and what effects could it have?
The shortest day in history
All over the world, 450 atomic clocks are in operation and follow the time with an accuracy in which they only lose about 1 second or only lose about 1 second every 100 million years. The clocks exist more than just proper time accounting. Everything from weather satellites to GPS satellites to telecommunications to nuclear missiles and other war weapons depend on precise timing to properly operate. So if both astronomers and the operators of the watches notice that the atomic ticks do not fall in step with the rotation of the earth, people absorb.
The shortest day that was ever recorded since the nuclear clocks were put into operation in the 1950s on July 5 in the 1950s after date and time when the earth shaved 1.66 milliseconds. Three years earlier, on June 30, 2022, things moved as quickly when the day came under the 24-hour wire in 1.59 milliseconds. But with three short days that were predicted by astronomers and watch observers in the next few weeks, this summer is even less common.
What makes the earth turn faster?
There are a number of reasons why the earth can change its speed in this way. But it is not yet clear which explanation is responsible this time.
The most likely cause is the position of the moon. Moon removal is an ever changing thing, with the moon pursuing an elliptical orbit around the earth. With its closest approach – or Perigee – the moon is only 224,000 miles away. The farthest – or on the Apogee – widens the gap to 251,655 miles. On the three fast days this summer, the moon will be on or near Apogee – a puzzle, since the moon is gravity so that the earth tends to slow down, not accelerated if the moon is further removed.
However, the orbit of the moon is not only elliptical, but also carved, angles between 18 ° and 28 ° compared to the earth equator. The sharper angle is the faster the earth’s railways, in this case the moon accelerates gravity and counteracts the braking effect that normally concerns. On the three days in question this summer, the moon is close to its 28 ° peak.
The moon is not the only thing that can shorten earthly days. Earthquakes can also redistribute the underground mass and accelerate the planet or slow down how a figure skater can change the speed of its rotation if it contests or expands. In 2005, an earthquake in Indonesia changed the polar mass of the earth about one inch to the east and reduced the length of 2.68 microseconds one day – or a millionth of a second. Lately, however, no significant earthquake has recently occurred, and the conditions for the current speed are excluded.
Does climate change affect the rotation of the earth?
Climate change – and apparently always – may also play a role. Last year, two studies financed by NASA found that Schmelz glaciers have been moving the center of its spin-at around 30 feet and changing the speed since 2000. In this case, the catch is the change to slow down and not accelerate the planet – by 1.33 milliseconds per century. If the heating continues at its current pace, it is expected to be increased by 2.62 milliseconds by 2.62 milliseconds by the end of the century.
Other factors, including increasing sea levels and warming – and thus the swelling – the atmosphere can also make a difference and slightly increasingly the scope of planet. Even the spring flowers of trees can play a role. “In the northern summer, the trees get leaves,” geophysicist Richard Holme from the University of Liverpool told Live Science. “This means that the mass is moved from the ground to the ground – far away from the spin axle of the earth.” In all of these cases, however, the effect is to slow down the earth and not to accelerate.
This brings scientists back into the moongraph force as the cause of the current acceleration – and this is a reason not to be annoyed by the somewhat shorter days. The earth and the moon have been dancing its dance for 4.5 billion years, and it has always been stable. Here is a bet that you still have a few billion years in the course of your run.
Write Jeffrey Kluger at jeffrey.kluger@time.com.
