Latest news with #Timeanddate
Yahoo
22-07-2025
- Science
- Yahoo
July 22 will be the second-shortest day of the year, scientists say
Tuesday, July 22 will be the second-shortest day of the year, as Earth completes a full rotation in less time than usual. The planet on Tuesday will experience a shorter rotation than the typical 24 hours, though not by much: 1.34 milliseconds less than usual, according to MORE: Climate change is altering the length of days on Earth, according to new research Typically, we think of the shortest day in the Northern Hemisphere as Dec. 21 or 22, which coincides with the winter solstice – July 21 or 22 in the Southern Hemisphere – which is the point at which the hemisphere is tilted farthest away from the sun. In those instances, however, it's only the number of hours of daylight that are affected, and not the length of time it takes for the Earth to make a full rotation on its axis. The 1.34-millisecond discrepancy in Tuesday's length is explained by differences in the gravitational pull between the Earth and the moon, which causes the Earth to spin more quickly, according to the Lunar and Planetary Institute. In recent years, Earth has broken its own speed records several times, including on July 5, 2024 – the shortest day ever measured, when the planet's full rotation was completed 1.66 milliseconds faster than usual, according to PHOTO: Spinning Globe This year, July 10 was measured as the shortest day of the year, with a full rotation occurring 1.36 milliseconds faster than normal. Aug. 5 is expected to be the third-shortest day of the year, projected to be 1.25 milliseconds shorter than usual. Earth completes one full rotation on its axis in 24 hours, or about 86,400 seconds, plus or minus a millisecond or so, according to Before 2020, Earth's shortest length of day was just 1.05 milliseconds shorter than usual. MORE: What to know about the winter solstice, the shortest day of the year If current trends continue, a full second may need to be subtracted from atomic clocks in the near future to accommodate for a "negative leap second," according to The system of leap seconds was introduced in the 1970s, according to Time and Date. While there have been dozens of positive leap seconds, in which a second was added, there has never been a negative leap second. The International Earth Rotation and Reference Systems Service, which monitor's the Earth's rotation, also determines whether to add or subtract a second. In its early days – about 4.5 billion years ago – Earth was spinning at a much faster rate, according to the Lunar and Planetary Institute. A full rotation only lasted between three and six hours. MORE: Melting polar ice is changing the Earth's rotation and affecting how we measure time: Study During the mid-Proterozoic period – between 2.5 billion years ago and 543 million years ago – the Earth had slowed such that a day lasted about 19 hours, according to a 2023 study published in Nature Geoscience. Since then, the length of an Earth day has slowed to its present 24 hours due to the fact that the moon's gravitational pull "steals" some of energy Earth uses to spin, in addition to causing tidal friction, according to the Institute. Additionally, climate change is causing days on Earth to become longer due to the melting of ice at the poles, according to a study published in the Proceedings of the National Academy of Sciences. As the poles melt, the redistribution of mass from the resulting sea-level rise also is increasing the length of a day, the researchers found.
Yahoo
21-07-2025
- Science
- Yahoo
Earth will spin faster on July 22 to create 2nd-shortest day in history
When you buy through links on our articles, Future and its syndication partners may earn a commission. Earth will complete a full rotation in slightly less time than usual on Tuesday, July 22, making it one of the shortest days ever recorded. The difference will be just 1.34 milliseconds less than the standard 24 hours — not something you'll notice — but it's part of a puzzling trend in Earth's rotational behavior that has been unfolding in recent years. If it continues, a second may need to be subtracted from atomic clocks around 2029 — a so-called negative leap second, which has never been done before. The speed of Earth's rotation isn't fixed. Long ago, a day was much shorter than the 24 hours — or 86,400 seconds — we're now accustomed to. According to a 2023 study, a day on Earth was approximately 19 hours for a significant part of Earth's early history, due to a balance between solar atmospheric tides and lunar ocean tides. However, over deep time, a day on Earth has become consistently longer. The primary culprit has been tidal friction from the moon, which has caused it to gradually move farther away from Earth. As it moves away, the moon saps Earth's rotational energy, causing Earth's rotation to slow and days to lengthen. So why the sudden reverse? From when records began (with the invention of the atomic clock) in 1973 until 2020, the shortest day ever recorded was 1.05 milliseconds less than 24 hours, according to But since 2020, Earth has repeatedly broken its own speed records. The shortest day ever measured occurred on July 5, 2024, when Earth's rotation was completed 1.66 milliseconds faster than usual. Looking ahead to 2025, scientists predicted that July 9, July 22, and Aug. 5 could be the shortest days of the year. However, new data suggests that July 10 took the lead as the shortest day so far in 2025, clocking in at 1.36 milliseconds less than 24 hours. On July 22, Earth is expected to complete its spin 1.34 milliseconds early, making it a close runner-up. If current predictions hold, Aug. 5 will be about 1.25 milliseconds shorter than usual, leaving July 22 as the second-shortest day of the year. There are signs the acceleration may be easing. The rate of decrease in day length appears to be slowing, but the underlying cause of the recent rotational changes remains elusive. One 2024 study suggested that the melting polar ice and rising sea levels may be influencing Earth's spin. However, rather than driving the acceleration, this redistribution of mass might be moderating it. A more likely culprit is deep below our feet — the slowing of Earth's liquid core, which could be redistributing angular momentum in a way that makes the mantle and crust spin slightly faster. "The cause of this acceleration is not explained," Leonid Zotov, a leading authority on Earth rotation at Moscow State University, told "Most scientists believe it is something inside the Earth. Ocean and atmospheric models don't explain this huge acceleration." Zotov predicts Earth's rotation may soon decelerate once again. If he's right, this sudden speeding-up could prove to be just a temporary anomaly in the planet's long-term trend toward slower rotation and longer days.
Yahoo
09-07-2025
- Science
- Yahoo
The Earth's Rotation Is About to Spin Up So Much That Tomorrow Will Be Much Shorter Than Today
The Earth's rotation is about to accelerate significantly. According to scientists, July 9, July 22, and August 5 of this year will be some of the shortest days in recent memory as a result, slicing well over a millisecond off the usual 24 hours, reports. That's despite the Earth's full rotation taking almost exactly 86,400 milliseconds, the equivalent of 24 hours. The short upcoming days buck a decades-long trend. Since 1972, scientists have sliced a "leap second" from the clock a whopping 27 times thanks to a steady deceleration. Our planet's sudden — and significant — acceleration caught scientists by surprise. "Nobody expected this," Moscow State University astronomer Leonid Zotov told "The cause of this acceleration is not explained." "Most scientists believe it is something inside the Earth," he added. "Ocean and atmospheric models don't explain this huge acceleration." Scientists have long found that numerous factors can influence the speed of the Earth's rotation, from changing sea levels to the Moon steadily increasing its orbit away from our planet. Using atomic clocks, we've been able to keep extremely close tabs on how these influences are affecting how we measure time on Earth. While its rotation had been steadily declining, the Earth reversed the trend in 2020, beating 60-year-old records for the shortest days 28 times. One possible explanation is that the Moon could be at its furthest point from the Earth's equator, as IFLScience explains. Another culprit could be powerful earthquakes knocking the Earth off its already tilted axis. In 2011, scientists found that a 9.0 earthquake in Japan may have been ferocious enough to shorten days on Earth by offsetting its axis by roughly 6.5 inches. But whether the Earth will continue its surprising trend of spinning faster and faster remains a subject of debate. "There is a general consensus the Earth will slow down again (deceleration will win), but there is a risk that acceleration may be effective for a few decades," Geoscience Australia scientist Oleg Titov told The Guardian. More on Earth's rotation: Scientists Build Device to Generate Electricity Using the Earth's Rotation
Yahoo
02-07-2025
- Yahoo
Summer 2025 will be shorter than usual. Here's why
Summer in the Northern Hemisphere will be shorter this year than last year by about 15 minutes, according to An event known as aphelion is happening on July 3. This means the Earth will be at its farthest point from the sun, a factor that does not cause the seasons, but does affect their length. Because Earth moves in an elliptical orbit around the sun, being further away means it travels slower along its orbit. This increases the time it takes to get from the solstice, the beginning of summer, to the equinox, the end of summer, usually making the season longer in the Northern Hemisphere, according to This year, however, is an exception. Due to the gravitational pull of the moon, Jupiter and other bodies in the solar system, Earth's orbit around the sun experiences subtle changes in its trajectory, which this year results in a slightly shorter summer, according to Summer in 2026 will be 3 minutes longer than this year, the website also notes. Despite a shorter summer this year, the effects of aphelion mean that summer in the Northern Hemisphere will continue to get longer. projects that in 1,000 years, summer will likely be six hours longer than it is now. Mattapan man hurt in stabbing charged in connection with woman's death U.S. warns travelers to avoid these Middle Eastern countries In Trump/Musk feud, social media users in China side with Musk Holland man indicted for murder in slaying of Austin Schepper earlier this year Suspect in fatal shooting in Springfield to be arraigned Thursday Read the original article on MassLive.
Forbes
24-06-2025
- Science
- Forbes
Summer 2025 Will Be 15 Minutes Shorter Than Last Year — Here's Why
Summer 2025 will be 15 minutes shorter than summer 2024. Summer this year in the Northern Hemisphere summer will be shorter — by exactly 15 minutes — than it was in 2024 because, according to of the ever-changing shape of Earth's orbit around the sun. Earth currently orbits the sun along a slightly elliptical path, which makes summers in the Northern Hemisphere longer than those in the Southern Hemisphere — and they're getting longer each year. However, that pattern is interrupted this year. Here's everything you need to know about why. Earth's Elliptical Orbit At 15:54 EDT on Thursday, July 3, Earth will reach its farthest point from the sun for the entire year. Astronomers call this aphelion. On that date, Earth receives less radiation from the sun, which is at its smallest in the sky. Earth next reaches its perihelion — its closest point to the sun — at 12:15 p.m. EDT on Jan. 3, 2026. Earth will get maximum radiation from the sun, which will be at its largest in the sky on that day. Crucially, none of this has anything to do with seasons on Earth, which is a result of the Earth's tilted axis. When the Northern Hemisphere is tilted toward the sun, it's summer, which is defined as between the solstice in June and the equinox in September. Why Summer Lasts Longer North Of The Equator Although it may not define the seasons, Earth's elliptical orbit around the sun does affect the duration of the seasons. At aphelion, Earth is farthest from the sun, so it takes a slightly longer path than when it's at perihelion when it moves slightly faster. Since aphelion occurs a couple of weeks after summer has begun in the Northern Hemisphere, aphelion makes summer last slightly longer than the Southern Hemisphere's summer (which occurs between the December solstice and the March equinox). As it stands, summer in the Northern Hemisphere is about four days longer than summer in the Southern Hemisphere, according to However, the gravitational influence of the sun, the moon and even Jupiter causes minute fluctuations in the shape and speed of Earth's orbit from year to year. In 2025, this will result in a slightly shorter summer than in 2024 — 93 days, 15 hours, and 37 minutes, down from 93 days, 15 hours, and 52 minutes. In 2026, summer will be three minutes longer than in 2025. Wishing you clear skies and wide eyes.
