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Yahoo
7 days ago
- 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
CNN
22-07-2025
- Science
- CNN
Earth is spinning faster, leading timekeepers to consider an unprecedented move
Earth is spinning faster this summer, making the days marginally shorter and attracting the attention of scientists and timekeepers. July 10 was the shortest day of the year so far, lasting 1.36 milliseconds less than 24 hours, according to data from the International Earth Rotation and Reference Systems Service and the US Naval Observatory, compiled by More exceptionally short days are coming on July 22 and August 5, currently predicted to be 1.34 and 1.25 milliseconds shorter than 24 hours, respectively. The length of a day is the time it takes for the planet to complete one full rotation on its axis —24 hours or 86,400 seconds on average. But in reality, each rotation is slightly irregular due to a variety of factors, such as the gravitational pull of the moon, seasonal changes in the atmosphere and the influence of Earth's liquid core. As a result, a full rotation usually takes slightly less or slightly more than 86,400 seconds — a discrepancy of just milliseconds that doesn't have any obvious effect on everyday life. However these discrepancies can, in the long run, affect computers, satellites and telecommunications, which is why even the smallest time deviations are tracked using atomic clocks, which were introduced in 1955. Some experts believe this could lead to a scenario similar to the Y2K problem, which threatened to bring modern civilization to a halt. Atomic clocks count the oscillations of atoms held in a vacuum chamber within the clock itself to calculate 24 hours to the utmost degree of precision. We call the resulting time UTC, or Coordinated Universal Time, which is based on around 450 atomic clocks and is the global standard for timekeeping, as well as the time to which all our phones and computers are set. Astronomers also keep track of Earth's rotation — using satellites that check the position of the planet relative to fixed stars, for example — and can detect minute differences between the atomic clocks' time and the amount of time it actually takes Earth to complete a full rotation. Last year, on July 5, 2024, Earth experienced the shortest day ever recorded since the advent of the atomic clock 65 years ago, at 1.66 milliseconds less than 24 hours. 'We've been on a trend toward slightly faster days since 1972,' said Duncan Agnew, a professor emeritus of geophysics at the Scripps Institution of Oceanography and a research geophysicist at the University of California, San Diego. 'But there are fluctuations. It's like watching the stock market, really. There are long-term trends, and then there are peaks and falls.' In 1972, after decades of rotating relatively slowly, Earth's spin had accumulated such a delay relative to atomic time that the International Earth Rotation and Reference Systems Service mandated the addition of a 'leap second' to the UTC. This is similar to the leap year, which adds an extra day to February every four years to account for the discrepancy between the Gregorian calendar and the time it takes Earth to complete one orbit around the sun. Since 1972, a total of 27 leap seconds have been added to the UTC, but the rate of addition has increasingly slowed, due to Earth speeding up; nine leap seconds were added throughout the 1970s while no new leap seconds have been added since 2016. In 2022, the General Conference on Weights and Measures (CGPM) voted to retire the leap second by 2035, meaning we may never see another one added to the clocks. But if Earth keeps spinning faster for several more years, according to Agnew, eventually one second might need to be removed from the UTC. 'There's never been a negative leap second,' he said, 'but the probability of having one between now and 2035 is about 40%.' The shortest-term changes in Earth's rotation, Agnew said, come from the moon and the tides, which make it spin slower when the satellite is over the equator and faster when it's at higher or lower altitudes. This effect compounds with the fact that during the summer Earth naturally spins faster — the result of the atmosphere itself slowing down due to seasonal changes, such as the jet stream moving north or south; the laws of physics dictate that the overall angular momentum of Earth and its atmosphere must remain constant, so the rotation speed lost by the atmosphere is picked up by the planet itself. Similarly, for the past 50 years Earth's liquid core has also been slowing down, with the solid Earth around it speeding up. By looking at the combination of these effects, scientists can predict if an upcoming day could be particularly short. 'These fluctuations have short-period correlations, which means that if Earth is speeding up on one day, it tends to be speeding up the next day, too,' said Judah Levine, a physicist and a fellow of the National Institute of Standards and Technology in the time and frequency division. 'But that correlation disappears as you go to longer and longer intervals. And when you get to a year, the prediction becomes quite uncertain. In fact, the International Earth Rotation and Reference Systems Service doesn't predict further in advance than a year.' While one short day doesn't make any difference, Levine said, the recent trend of shorter days is increasing the possibility of a negative leap second. 'When the leap second system was defined in 1972, nobody ever really thought that the negative second would ever happen,' he noted. 'It was just something that was put into the standard because you had to do it for completeness. Everybody assumed that only positive leap seconds would ever be needed, but now the shortening of the days makes (negative leap seconds) in danger of happening, so to speak.' The prospect of a negative leap second raises concerns because there are still ongoing problems with positive leap seconds after 50 years, explained Levine. 'There are still places that do it wrong or do it at the wrong time, or do it (with) the wrong number, and so on. And that's with a positive leap second, which has been done over and over. There's a much greater concern about the negative leap second, because it's never been tested, never been tried.' Because so many fundamental technologies systems rely on clocks and time to function, such as telecommunications, financial transactions, electric grids and GPS satellites just to name a few, the advent of the negative leap second is, according to Levine, somewhat akin to the Y2K problem — the moment at the turn of the last century when the world thought a kind of doomsday would ensue because computers might have been unable to negotiate the new date format, going from '99' to '00.' Climate change is also a contributing factor to the issue of the leap second, but in a surprising way. While global warming has had considerable negative impacts on Earth, when it comes to our timekeeping, it has served to counteract the forces that are speeding up Earth's spin. A study published last year by Agnew in the journal Nature details how ice melting in Antarctica and Greenland is spreading over the oceans, slowing down Earth's rotation — much like a skater spinning with their arms over their head, but spinning slower if the arms are tucked along the body. 'If that ice had not melted, if we had not had global warming, then we would already be having a leap negative leap second, or we would be very close to having it,' Agnew said. Meltwater from Greenland and Antarctica ice sheets has is responsible for a third of the global sea level rise since 1993, according to NASA. The mass shift of this melting ice is not only causing changes in Earth's rotation speed, but also in its rotation axis, according to research led by Benedikt Soja, an assistant professor at the department of civil, environmental and geomatic engineering of The Swiss Federal Institute of Technology in Zurich, Switzerland. If warming continues, its effect might become dominant. 'By the end of this century, in a pessimistic scenario (in which humans continue to emit more greenhouse gases) the effect of climate change could surpass the effect of the moon, which has been really driving Earth's rotation for the past few billions of years,' Soja said. At the moment, potentially having more time to prepare for action is helpful, given the uncertainty of long-term predictions on Earth's spinning behavior. 'I think the (faster spinning) is still within reasonable boundaries, so it could be natural variability,' Soja said. 'Maybe in a few years, we could see again a different situation, and long term, we could see the planet slowing down again. That would be my intuition, but you never know.'
CNN
21-07-2025
- Science
- CNN
Earth is spinning faster, making days shorter — here's why scientists say it could be a problem
Earth is spinning faster this summer, making the days marginally shorter and attracting the attention of scientists and timekeepers. July 10 was the shortest day of the year so far, lasting 1.36 milliseconds less than 24 hours, according to data from the International Earth Rotation and Reference Systems Service and the US Naval Observatory, compiled by More exceptionally short days are coming on July 22 and August 5, currently predicted to be 1.34 and 1.25 milliseconds shorter than 24 hours, respectively. The length of a day is the time it takes for the planet to complete one full rotation on its axis —24 hours or 86,400 seconds on average. But in reality, each rotation is slightly irregular due to a variety of factors, such as the gravitational pull of the moon, seasonal changes in the atmosphere and the influence of Earth's liquid core. As a result, a full rotation usually takes slightly less or slightly more than 86,400 seconds — a discrepancy of just milliseconds that doesn't have any obvious effect on everyday life. However these discrepancies can, in the long run, affect computers, satellites and telecommunications, which is why even the smallest time deviations are tracked using atomic clocks, which were introduced in 1955. Some experts believe this could lead to a scenario similar to the Y2K problem, which threatened to bring modern civilization to a halt. Atomic clocks count the oscillations of atoms held in a vacuum chamber within the clock itself to calculate 24 hours to the utmost degree of precision. We call the resulting time UTC, or Coordinated Universal Time, which is based on around 450 atomic clocks and is the global standard for timekeeping, as well as the time to which all our phones and computers are set. Astronomers also keep track of Earth's rotation — using satellites that check the position of the planet relative to fixed stars, for example — and can detect minute differences between the atomic clocks' time and the amount of time it actually takes Earth to complete a full rotation. Last year, on July 5, 2024, Earth experienced the shortest day ever recorded since the advent of the atomic clock 65 years ago, at 1.66 milliseconds less than 24 hours. 'We've been on a trend toward slightly faster days since 1972,' said Duncan Agnew, a professor emeritus of geophysics at the Scripps Institution of Oceanography and a research geophysicist at the University of California, San Diego. 'But there are fluctuations. It's like watching the stock market, really. There are long-term trends, and then there are peaks and falls.' In 1972, after decades of rotating relatively slowly, Earth's spin had accumulated such a delay relative to atomic time that the International Earth Rotation and Reference Systems Service mandated the addition of a 'leap second' to the UTC. This is similar to the leap year, which adds an extra day to February every four years to account for the discrepancy between the Gregorian calendar and the time it takes Earth to complete one orbit around the sun. Since 1972, a total of 27 leap seconds have been added to the UTC, but the rate of addition has increasingly slowed, due to Earth speeding up; nine leap seconds were added throughout the 1970s while no new leap seconds have been added since 2016. In 2022, the General Conference on Weights and Measures (CGPM) voted to retire the leap second by 2035, meaning we may never see another one added to the clocks. But if Earth keeps spinning faster for several more years, according to Agnew, eventually one second might need to be removed from the UTC. 'There's never been a negative leap second,' he said, 'but the probability of having one between now and 2035 is about 40%.' The shortest-term changes in Earth's rotation, Agnew said, come from the moon and the tides, which make it spin slower when the satellite is over the equator and faster when it's at higher or lower altitudes. This effect compounds with the fact that during the summer Earth naturally spins faster — the result of the atmosphere itself slowing down due to seasonal changes, such as the jet stream moving north or south; the laws of physics dictate that the overall angular momentum of Earth and its atmosphere must remain constant, so the rotation speed lost by the atmosphere is picked up by the planet itself. Similarly, for the past 50 years Earth's liquid core has also been slowing down, with the solid Earth around it speeding up. By looking at the combination of these effects, scientists can predict if an upcoming day could be particularly short. 'These fluctuations have short-period correlations, which means that if Earth is speeding up on one day, it tends to be speeding up the next day, too,' said Judah Levine, a physicist and a fellow of the National Institute of Standards and Technology in the time and frequency division. 'But that correlation disappears as you go to longer and longer intervals. And when you get to a year, the prediction becomes quite uncertain. In fact, the International Earth Rotation and Reference Systems Service doesn't predict further in advance than a year.' While one short day doesn't make any difference, Levine said, the recent trend of shorter days is increasing the possibility of a negative leap second. 'When the leap second system was defined in 1972, nobody ever really thought that the negative second would ever happen,' he noted. 'It was just something that was put into the standard because you had to do it for completeness. Everybody assumed that only positive leap seconds would ever be needed, but now the shortening of the days makes (negative leap seconds) in danger of happening, so to speak.' The prospect of a negative leap second raises concerns because there are still ongoing problems with positive leap seconds after 50 years, explained Levine. 'There are still places that do it wrong or do it at the wrong time, or do it (with) the wrong number, and so on. And that's with a positive leap second, which has been done over and over. There's a much greater concern about the negative leap second, because it's never been tested, never been tried.' Because so many fundamental technologies systems rely on clocks and time to function, such as telecommunications, financial transactions, electric grids and GPS satellites just to name a few, the advent of the negative leap second is, according to Levine, somewhat akin to the Y2K problem — the moment at the turn of the last century when the world thought a kind of doomsday would ensue because computers might have been unable to negotiate the new date format, going from '99' to '00.' Climate change is also a contributing factor to the issue of the leap second, but in a surprising way. While global warming has had considerable negative impacts on Earth, when it comes to our timekeeping, it has served to counteract the forces that are speeding up Earth's spin. A study published last year by Agnew in the journal Nature details how ice melting in Antarctica and Greenland is spreading over the oceans, slowing down Earth's rotation — much like a skater spinning with their arms over their head, but spinning slower if the arms are tucked along the body. 'If that ice had not melted, if we had not had global warming, then we would already be having a leap negative leap second, or we would be very close to having it,' Agnew said. Meltwater from Greenland and Antarctica ice sheets has is responsible for a third of the global sea level rise since 1993, according to NASA. The mass shift of this melting ice is not only causing changes in Earth's rotation speed, but also in its rotation axis, according to research led by Benedikt Soja, an assistant professor at the department of civil, environmental and geomatic engineering of The Swiss Federal Institute of Technology in Zurich, Switzerland. If warming continues, its effect might become dominant. 'By the end of this century, in a pessimistic scenario (in which humans continue to emit more greenhouse gases) the effect of climate change could surpass the effect of the moon, which has been really driving Earth's rotation for the past few billions of years,' Soja said. At the moment, potentially having more time to prepare for action is helpful, given the uncertainty of long-term predictions on Earth's spinning behavior. 'I think the (faster spinning) is still within reasonable boundaries, so it could be natural variability,' Soja said. 'Maybe in a few years, we could see again a different situation, and long term, we could see the planet slowing down again. That would be my intuition, but you never know.'
Miami Herald
27-06-2025
- Politics
- Miami Herald
Usha Vance Addresses Her First Lady Chances
Second Lady Usha Vance has opened up about the prospect of husband Vice President JD Vance ascending to the presidency in 2028, and the chances of becoming the next First Lady. In a candid interview with Meghan McCain, recorded at the Vice-Presidential residence at One Observatory Circle in Washington, D.C, she said: "I'm not plotting out next steps," adding that she would be happy to be "along for the ride" if her husband became president. Newsweek contacted the White House via online form on Friday for comment. Usha Vance has passed the historic milestone of being the first South Asian and Hindu Second Lady, but she is steering clear of stating any political ambition, whether in the short term or as potential First Lady. As Vice President, husband JD is widely regarded as the leading contender for the Republican presidential nomination in 2028, though he has yet to formally declare his candidacy. Usha Vance addressed the subject on Wednesday's episode of the podcast Citizen McCain with Meghan McCain, with her host describing it as a "very exciting possibility." "There is not a small chance you could be our first lady in a few years," said former View co-host McCain. "I wanted to know is that stressful for you, is it exciting, is that something you think about, is this something everyone is asking you everywhere you go?" Usha offered a measured response, emphasizing that her current priority lies squarely in the present moment: "Well, people do ask about it," the attorney said, adding, "three years ago, or maybe it was four years ago at this point, I had absolutely no intention of leading any sort of life in politics, it really is that rapid. "And then when we moved our kids to school in this area it was with no intention whatsoever of JD running for a new office and so my attitude is that this is a four-year period where I have a set of responsibilities to my family, to myself, to obviously the country, and that's really what I'm focused on." "I'm not plotting out next steps or really trying for anything after this," she noted. "And in a dream world, eventually I'll be able to live in my home and kind of continue my career and all those sorts of things. "And if that happens in four years, I understand, if that happens at some other point in the future, I understand, I'm just sort of along for the ride and enjoying it while I can." Usha also announced during the interview that the couple are expecting their third child. She also revealed that it's been "really hard" for JD to quit driving since assuming office. The Second Lady discussed living at the Naval Observatory in Washington, D.C, and how much she appreciates the staff there. However, the couple maintains close ties to Ohio and considers it their true home. Meghan McCain on her podcast to Vance: "I really just am such a fan of yours, I think you're so cool, I really hope you are a first lady someday, and I don't mind saying that, you don't have to say, it I will." McCain also praised Usha's humility and perspective on motherhood and public life. Usha talked about looking forward to bringing projects to light that she is interested in and working on things she is excited about. She recently launched a children's reading initiative, her first public-facing project since her husband became Vice President. Related Articles Usha Vance Opens Up About Family Life in Rare InterviewTrump Doesn't Rule Out Military Force to Take GreenlandPutin Issues Arctic 'Conflicts' Warning Over Trump's Greenland PlansGreenland Solves Political Crisis Hours Before JD Vance Visit 2025 NEWSWEEK DIGITAL LLC.
Fox News
25-06-2025
- Politics
- Fox News
Second Lady Usha Vance opens up about interfaith parenting with Vice President JD Vance
Second Lady Usha Vance opened up in a new interview about how she and husband JD Vance raise their three children in an interfaith household, as Usha is Hindu and the vice president is Catholic. Usha Vance spoke to Meghan McCain on her podcast, "Citizen McCain," about raising her three children, Ewan, Vivek and Mirabel, at the Naval Observatory, as well as the transition into becoming the second couple. "At the time when I met JD, he wasn't Catholic, and he converted later and when he converted, we had a lot of conversations about that because it was actually after we had our first child, maybe it was after Vivek was born too," she said. "When you convert to Catholicism it comes with several important obligations, like to raise your child in the faith and all that." "We had to have a lot of real conversations about how do you do that, when I'm not Catholic, and I'm not intending to convert or anything like that," Usha continued. The second lady said it was helpful because she felt she had a say over the directions of their lives. "So what we've ended up doing is we send our kids to Catholic school, and we have given them each the choice, right? They can choose whether they want to be baptized Catholic and then go through the whole step-by-step process with their classes in school," she said. Vance said their oldest child has done that, and added that they make going to church a "family experience." "The kids know that I'm not Catholic, and they have plenty of access to the Hindu tradition from books that we give them, to things that we show them, to the recent trip to India, and some of the religious elements of that visit," Vance continued. Usha Vance was also the subject of a New York Times profile published Wednesday, which described some friends as "bewildered" by her going from once being a Democrat to the spouse of a Republican vice president. Others said, however, that she naturally soured on the left over time, and she was reportedly outraged at Democratic attacks on future Supreme Court Justice Brett Kavanaugh during his wrenching confirmation process in 2018; she clerked for Kavanaugh when he sat on the U.S. Court of Appeals for the D.C. Circuit. "People close to the vice president, who went from being a vocal critic of now-President Trump to his running mate, argue that Ms. Vance went on a similar but less public journey that soured her on the left," the Times reported. Usha Vance spoke to Fox News in August while her husband was on the campaign trail and told host Ainsley Earhardt how she deals with negative press coverage of her husband. "Sometimes I don't see it all, and sometimes I do see it and I look at and think, well, this is not the JD I know, this is not accurate," she said at the time. "And other times it might span discussions or thoughts about what we should do next or how we should live. But I think we've been doing this now for a little while, and I've gotten kind of accustomed to it and grown a bit of a thick skin to it." Usha Vance met JD Vance at Yale University, and the couple married in 2014. Vice President Vance, 40, is the third-youngest vice president in history and first millennial to hold the office, and Usha Vance is the first Indian-American second lady.
