According to the data of the US maritime observatory with the international world return and reference systems service, July 10 was the shortest day of the year.
That day, 1.36 milliseconds took shorter. Similarly, on July 22 and August 5, the days are expected to take a shorter time of 1.34 and 1.25 milliseconds, respectively.
One day, the time to complete the full turn of the Earth around its axis is called and this is about 86 thousand 400 seconds, ie 24 hours.
However, in practice, each turn varies very little. This is due to the mass attraction of the Moon, the seasonal changes in the atmosphere and the movements of the Earth’s liquid core.
Therefore, each turn may take less than 24 hours or long with a difference of a few milliseconds. Although this difference is not felt in daily life, it is of great importance for computers, satellites and communication systems.
Atom clocks are used to compensate for these small time differences. These watches, which were first used in 1955, measures the time with extraordinary precision by counting the vibrations of the atoms held in vacuum rooms.
This system is called UTC, ie coordinated universal time and is determined by approximately 450 atomic clocks in the world. Phones, computers and GPS systems operate according to UTC.
The world that is increasingly accelerating leaves time behind
According to CNN International; The return rate of the Earth is also monitored by astronomers thanks to the satellites that measure the location according to fixed stars. These observations reveal microsecure differences between atomic clocks and the real return of the Earth. On July 5, 2024, the shortest day was measured since the invention of the atomic clock: It took less than 24 hours of 1.66 milliseconds.
Geophysicist from the University of California Scripps Occupation Institute. According to Duncan AGNEW, “There has been a trend towards faster days since 1972, but this is followed by a bumpy course. Just like the stock market, there are long -term trends, but sometimes sudden rise and decreases are happening.”
By 1972, the return of the Earth had slowed down compared to the atomic clocks that it had to be added to a plus seconds (Leap Second) to the UTC system.
This system was now aimed at closing the difference between the calendar and astronomical time, similar to the year application.
Since then, a total of 27 seconds have been added to the UTC. However, the number of these additions gradually decreased; While 9 times in the 1970s were added, no new seconds have been added since 2016.
In 2022, the General Conference of International Weights and Measures decided to completely remove the second by 2035. However, if the world accelerates for several years, it may need to be removed this time.
“A negative anymore has never been a second,” said Agnew, “but until 2035, such a possibility is around 40 percent,” he said.
Why is the world accelerating?
According to AGNEW, most of the short -term changes are caused by the moon and tides. When the Moon is on the Ecuador, it slows down the return of the Earth, and accelerates when it is north or south.
In addition, atmospheric conditions in summer accelerate the return of the Earth. The slowdown of the atmosphere with the displacement of jet currents leads to the planet to rotate faster, with the necessity of protecting angular momentum according to the rules of physics. Similarly, while the Earth’s liquid seed slows down, solid outer layers are accelerating.
With the combination of these factors, it can be predicted why some days will be short. “If the world is accelerating one day, the next day it tends to accelerate,” he said. However, this correlation disappears in the long run. Therefore, the international world return service does not predict more than one year.
Negative now why ask for seconds?
According to Levine, a single short day does not cause any problems and if this trend persists, it may be necessary to apply negative to seconds. “When the second system was defined in 1972, no one thought that a negative second might need it,” Levine said that it was only added as a theoretical precautionary measure. “But now this possibility really has emerged.”
Levine states that even seconds still cause systemic problems: “Some systems do the wrong, apply it at the wrong time, or incorrect value.” The negative is much larger because it is no longer tried. Systems such as financial systems, electric networks, telecommunications infrastructure and GPS work dependent on time. For this reason, negative is now compared to the chaos of a second, the famous Y2K problem in 2000.
Melting ice delays this process
Climate change also affects the world’s return speed. However, this effect is surprisingly slowing down. The melting of glaciers in Antarctica and Greenland causes the glacier mass to spread to the seas. This slows down the return of the Earth. Just like the slowing of an ice skater who opens his arms. If these ice had not melted, according to AGNEW, “negative would have become a much closer problem than today.”
According to NASA, the ice melting from Greenland and Antarctica has been responsible for one -third of the sea -level rise since 1993.
According to Benedikt Soja from the Swiss Federal Institute of Technology in Zurich, this melting affects not only the speed of return, but also the Earth’s return axis. SOJA, “until the end of the century, if greenhouse gas emissions are high, the effect of climate change can become more dominant than the effect of the Moon for billions of years,” he said.
SOJA said, şey Now everything can still be within the limits of natural variability, ”he said, the possibility of a long -term slowing down should not be ignored. “But we can never be sure,” he said.
