Latest news with #shortestDay
Yahoo
05-08-2025
- Science
- Yahoo
Aug. 5 might be one of the shortest days of the year: Here's why
Scientists predict Aug. 5 just might be one of the shortest days of 2025. On Tuesday, Earth may rotate up to 1.25 milliseconds faster, according to an updated prediction shared on Multiple factors can contribute to changes in Earth's rotation rates, including atmospheric wind currents, the position of Earth's seas, and the position of the moon. Jason Nordhaus, an associate professor of physics at Rochester Institute of Technology in New York, says scientists have been tracking and collecting precise data since the 1960s and 70s that show the length of days has fluctuated over the decades. "It used to be that the Earth is actually spinning much slower, maybe like, three milliseconds slower per day," Nordhaus told ABC News. "Then, it's been steadily heading in the opposite direction, and then in the last maybe five years, it's really spun up. It's going faster, and so you're getting these shorter days." July 22 will be the second-shortest day of the year, scientists say Earth's rotational changes are imperceptible to the human eye, said Nordhaus. "This is nothing anyone would notice," the professor said. "If you wake up in the morning and you look out, you don't know what a millisecond is like." But the tiny changes can be picked up by the atomic clock, a precise tool scientists use for space navigation and for GPS systems, and the changes are more noticeable over time. "If you get it wrong and you're off by a millisecond or two milliseconds, I think that works out to be something like, you get your positions off by maybe 50 centimeters to maybe 100 centimeters. And so, then if you accumulate that over the course of a year, you might be off by half a kilometer in your GPS system," Nordhaus explained. Why July 9 was the shortest day on record Scientists use the idea of leap seconds to take the changes into consideration, similar to the concept of a leap year. "If you look back through the '70s to today, there's been something around … 25 or 30 leap seconds have been added to counter all this over time," said Nordhaus. This summer, there have been three other days – July 9, July 10 and July 22 – where Earth has appeared to rotate more quickly than usual. On July 9, Earth appeared to rotate 1.23 milliseconds faster, 1.36 milliseconds faster the following day and then about 1.34 milliseconds faster on July 22, according to Solve the daily Crossword
Yahoo
05-08-2025
- Science
- Yahoo
Earth's rotation is speeding up today for the 3rd and final time this summer
Aug. 5 will be one of the shortest days of the year — by 1.25 milliseconds. Planet Earth is spinning a little faster today — resulting in one of the shortest days of the year. But the change will be so minuscule you won't even notice. We're talking even less time than the blink of an eye. In fact, several milliseconds will be shaved off the 24 hours it takes for Earth to complete a full rotation on July 9, July 22 and Aug. 5 due to changes in the speed of the Earth's rotation. Why is Earth's rotation speed changing? Planet Earth is our timekeeper, but it's not perfect. It takes our planet 24 hours — one day — to complete one full rotation on its axis, which breaks down to 86,400 seconds. But Earth's rotation could change by a millisecond (.001 seconds) or two every day. The orbit of the moon can have an effect on how fast the Earth spins around. 'Our planet spins quicker when the moon's position is far to the north or south of Earth's equator,' according to 'Earthquakes, volcanoes, tidal forces, subterranean geology, and many other mechanisms can cause the planet's rotation to slow down or speed up, and those micro-adjustments can trend over time,' Popular Mechanics reported. The 8.9 magnitude earthquake that struck Japan in 2011 accelerated Earth's rotation, shortening the length of the standard 24-hour day by 1.8 microseconds (0.0018 milliseconds). These tiny day-to-day fluctuations in the Earth's spin speed began to be measured in the 1950s with atomic clocks. Any number above or below the standard 86,400 seconds is called the length of day (LOD). The shortest day recorded was on July 5, 2024, when Earth completed its full rotation 1.66 milliseconds faster than the standard 86,400 seconds. When will this happen? There are a total of three days this summer — July 9, July 22 and Aug. 5 — when the moon will be around its furthest distance from Earth's equator, resulting in a minuscule increase in the Earth's spin speed. According to here are the lengths of those days: July 9: Day shortened by 1.23 milliseconds July 22: Day shortened by 1.36 milliseconds Aug. 5: Day is shortened by 1.25 milliseconds Wait — isn't there another day that's considered the shortest of the year? What feels like the shortest day of the year in the Northern Hemisphere is known as the winter solstice, when Earth is tilted away from the sun at its maximum. This results in the fewest amount of daylight hours all year and occurs in mid-December. Will Earth always have 24 hours in a day? There weren't always 24 hours in a day. Researchers believe that in the Jurassic Period, it took Earth just 23 hours to make a complete rotation around its axis. Scientists have found that the length of a day on Earth is increasing each century by about 1.7 milliseconds. Over time, that adds up. Experts think that 200 million years from now, there will be 25 hours in a full day. Solve the daily Crossword
Yahoo
05-08-2025
- Science
- Yahoo
Why could Aug. 5 be shorter than 24 hours?
If you seem not to be able to get through the to-do list on Aug. 5, you'll at least have an excuse. Tuesday is predicted to be one of the shortest days in the year, marking the latest time the Earth could see a day shortened by more than a millisecond. Scientists predict that Aug. 5 will be 1.34 milliseconds shorter, according to the International Earth Rotation and Reference System Service and the U.S. Naval Observatory, published by TimeandDate. The millisecond mark has been broken a handful of times this year, with the most recent being July 11, according to the data published by TimeandDate. The predictions do not always come to pass, as July 22 had been predicted to be over a millisecond short, but the data revealed that only 0.87 milliseconds were shaved off, according to the Observatory's data. Earth takes 24 hours to complete a full rotation in a standard day, equal to exactly 86,400 seconds. Until 2020, the shortest day ever recorded by atomic clocks was 1.05 milliseconds short, meaning that Earth completed one daily rotation in 1.05 milliseconds less than the expected 86,400 seconds. "Since then, however, Earth has managed to shatter this old record every year by around half a millisecond," astrophysicist Graham Jones wrote for TimeAndDate. The shortest day recorded so far occurred July 5, 2024, when it came in 1.66 milliseconds short. The shortest day recorded this year was July 10, which came in 1.37 milliseconds short. Why is this happening? The Earth's rotation is influenced by the core and the atmosphere, according to Scientific American. The science magazine says that the core's spin has been slowing, though for unknown reasons, meaning that the rest of the planet must speed up to compensate. "The core is what changes how fast the Earth rotates on periods of 10 years to hundreds of years," Duncan Agnew, a geophysicist at the Scripps Institution of Oceanography, told the magazine. "The core has been slowing down for the last 50 years, and as a result, the Earth has been speeding up." Atmospheric forces cause the rotation rate of the Earth to speed up in the summer of the Northern Hemisphere, according to Scientific American. Forces caused by the moon also affect the rate the Earth spins. The magazine notes that on the geologic timescale, the Earth has been slowing, with the rotation taking half an hour less 70 million years ago. Will the sped-up day be noticeable? Of course, you're unlikely to notice such a minuscule difference in your standard 24-hour day. But scientists who track and operate atomic clocks may be facing a bit of a predicament. First introduced in the 1950s, atomic clocks replaced how scientists previously measured the length of a day by tracking the Earth's rotation and the position of the sun. The clocks are also capable of measuring in billionths of a second, or nanoseconds, which are synchronized globally to Coordinated Universal Time (UTC). If the clocks are thrown off even a tiny amount, it could also throw off computers, servers, GPS signals, and other networks that rely on accurate times, David Gozzard, an experimental physicist at the University of Western Australia, told the Guardian. This article originally appeared on USA TODAY: Aug. 5 might be a short day, see how much time could be trimmed off Solve the daily Crossword
Daily Mail
10-07-2025
- Science
- Daily Mail
Exact date when the world's next shortest day will occur as Earth's rotation expected to speed up AGAIN
If it feels like the summer is slipping away faster than ever, you're not alone. On July 9, the world experienced one of the shortest days in recorded history, at 1.3 milliseconds shorter than the average day. Now, scientists have revealed exactly when the next shortest days will occur as Earth's rotation speeds up once again. Scientists predict that July 22 and August 5 will be even shorter than July 9, at 1.38 and 1.51 milliseconds shorter than average. This is because the moon will be at its furthest point from Earth, reducing how much the tides hold back the planet's rotation. Since an average blink lasts about 100 milliseconds, you won't be able to notice this difference. However, Earth's rotation has been unexpectedly speeding up over the last few years, with atomic clocks picking up the change in 2020 and 2022. While scientists have suggested multiple theories from changes in the atmosphere to the weakening magnetic field, the exact reason for the acceleration remains a mystery. Normally, the Earth takes 24 hours, or 86,400 seconds, to rotate fully on its axis in a 'solar day'. While this constant might be something we often take for granted, the Earth's rotation isn't actually stable. On average, the Earth is actually slowing down by about two milliseconds per century. This means that a T Rex in the Mesozoic era, about 250 million years ago, lived through days that were 23 hours long. Even as early as the Bronze Age, the average day was about 0.47 seconds shorter, and in 200 million years' time, the days will be 25 hours long. This slowing is largely due to the pull of the moon in a process called tidal braking. When the moon's gravity pulls on Earth, it causes the oceans to bulge out slightly. In addition to creating the tides, this tug actually pulls Earth backwards and slows its rotation. However, when the moon is at its furthest point from Earth, known as the apogee, this pull is weaker and the planet can spin faster than normal. That is why July 22 and August 5 will be so much faster than other days this year. But these exceptionally short days are only possible because the Earth is currently in an unusual phase of acceleration. This change has been so sudden that some experts think we will need to subtract a leap second for the first time ever in 2029. Prior to 2020, there had never been a day much more than a millisecond shorter than average according to the US Naval Observatory and international Earth rotation services. Now, scientists have recorded a string of days more than 1.3 milliseconds shorter than normal. The shortest day ever recorded occurred on July 5 last year, which was a full 1.66 milliseconds shorter. Dr Leonid Zotov, a leading authority on Earth rotation at Moscow State University, told Time and Date: 'Nobody expected this. The cause of this acceleration is not explained.' Overall, scientists expected the planet's rotation to slow. This is partly due to the slowing rotation of the inner core, which affects Earth's rotation in space Most scientists believe that this is due to something changing deep within Earth's core, which is affecting the planet's momentum. In the future, Dr Zotov and other scientists expect that the trend will return to gradual slowing. 'I think we have reached the minimum. Sooner or later, Earth will decelerate,' says Dr Zotov. This is because there are a number of factors which are jointly working to slow the planet down. In addition to tidal braking, scientists also found that the planet's inner core began to slow around 2010 and is now moving backwards, subtly affecting the Earth's rotation in space. This is expected to slightly slow the planet down over the coming years. Likewise, recent research shows that melting ice and moving groundwater, linked to climate change, have increased the length of our days by 1.33 milliseconds per century between 2000 and 2018.
Yahoo
10-07-2025
- Science
- Yahoo
Why July 9 May Be the Shortest Day in Recorded History
Originally appeared on E! Online The summer months may bring longer daylight hours, but the days themselves are actually getting shorter. In fact, July 9 could end up being the shortest day ever recorded by the International Earth Rotation and Reference Systems Service (IERS), which tracks the length of each day down to the millisecond. It's expected to clock in at roughly 1.3 milliseconds shorter than the typical 86,400 seconds in a 24-hour span, according to the BBC. The phenomenon may even occur more than once, as July 22 and Aug. 5 are also predicted to be slightly shorter than normal. On these dates, the moon will be furthest from the equator, which experts have tied to the momentum of the Earth's rotation, per the outlet. Indeed, experts have observed a steady acceleration in the Earth's rotation since 2020. Currently, the shortest day ever was logged on July 5, 2024, which was 1.66 milliseconds shorter than usual, according to Time and Date. For some of the most out-of-this-world celebrity quotes, keep reading. More from E! Online Kanye "Ye" West's Wife Bianca Censori Looks So Different With Bold New Hairstyle Kate Middleton's Personal Assistant of 15 Years Exits Palace Camp Mystic Survivor, 13, Details "Hysterical" Scene During Texas Flood But the moon's placement alone doesn't account for the years-long trend of Earth's rotation speeding up. 'The cause of this acceleration is not explained,' Moscow State University researcher Leonid Zotov told Time and Date in an interview published June 16. 'Most scientists believe it is something inside the Earth. Ocean and atmospheric models don't explain this huge acceleration.' While most people are unlikely to notice the effects of the occurrences, the IERS has periodically added a leap second to the year—most recently in 2016—to ensure high-precision clocks are unaffected. But the recent string of condensed days could have a subtle effect in the future, resulting in a leap second being taken off the clock for the first time in 2029. Fortunately, though, Zotov predicted that the Earth's momentum would eventually subside. 'I think we have reached the minimum,' he said. 'Sooner or later, Earth will decelerate.' For some of the most out-of-this-world celebrity quotes, keep reading. Gayle KingKaty PerryWilliam ShatnerLance BassMichael StrahanKim KardashianElon MuskLeonardo DiCaprioJustin BieberTom HanksAshton KutcherPrince WilliamCameron DiazMichael FassbenderCharlize TheronParis Hilton For the latest breaking news updates, click here to download the E! News App
