Latest news with #milliseconds
Yahoo
6 days ago
- 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
CNET
6 days ago
- Science
- CNET
Earth Is Spinning Weirdly Faster, Making This Tuesday One of the Shortest Days Ever
Earth's rotation is randomly speeding up, and nobody is quite sure why. These speedups, which have occurred several times over the last few years, haven't had any effect on daily life, but they also haven't gone unnoticed by science. Tuesday, Aug. 5 is the next date when Earth's rotation is expected to speed up, shortening the day by between 1.25 and 1.51 milliseconds. According to Time and Date, the current prediction is set by the International Earth Rotation and Reference Systems Service and the US Naval Observatory. The original prediction was 1.51 milliseconds, but it's since been updated to 1.25 milliseconds. This is also the third time Earth's rotation has sped up for a day this summer. The other two instances occurred on July 10 and July 22. Should the first prediction be accurate, Aug. 5, 2025, will be the third shortest day on record behind June 30, 2022, when the Earth spun 1.59 milliseconds faster, and July 5, 2024, when it completed its rotation 1.66 milliseconds faster. If the prediction is off, then it may succeed those two as the shortest day Earth has seen in recorded history. For reference, Earth generally takes approximately 86,400 seconds to make one full rotation. One millisecond is 0.001 seconds. So, this won't be noticeable to humans and will not affect anything. What's causing Earth to spin faster? There are numerous reasons why Earth could be spinning faster. The prevailing opinion is that it's due to the moon's current position over Earth. When the moon is further north or south than Earth's equator, it can impact how fast the planet spins. On Aug. 5, 2025, the moon will be quite a bit further south than the equator, which is likely causing the slightly faster spin. This is expected to have a short-term impact on Earth's orbit. Science can't explain it Scientists are puzzling over why Earth is speeding up at all. Approximately 245 million years ago, the dinosaurs roamed, and days were an hour and a half shorter than they are today. Earth's rotation has been slowing ever since, mostly due to the moon's impact on Earth's oceans. Science has measured Earth's rotation subtly slowing down since official records began in 1973. However, a recent trend shows that Earth's rotation is speeding up, and since these faster days are mostly explained by the moon's orbit, science has yet to fully explain why. A research paper posted in Nature in 2023 suggests that Earth's core may have started slowing down as recently as 2010, which would explain Earth's faster rotation. However, confirmation doesn't yet exist.
