On June 29, Earth actually did record the shortest day Since the adoption of the atomic clock standard in 1970—1.59 milliseconds less than 24 hours—scientists say this is a normal fluctuation.
Still, news of the faster rotation prompted misleading posts on social media about the measurement’s significance, leading some to express concern about its implications.
“They reported that the earth is spinning faster, which should be bigger news,” he said in a tweet that has been shared nearly 35,000 times. “We’ve become so vulnerable to disaster at this point, what’s next.”
Some Twitter users joked about the tweets and questioned the magnitude of the measurement. Others expressed concern about how it would affect them.
But scientists told AP that the Earth’s rotation rate is constantly changing and the record reading is not cause for panic.
“It’s completely normal,” said Steven Merkovitz, a scientist and project manager at NASA’s Goddard Space Flight Center. “There’s nothing magical or special about it. It’s not such an extreme data point that all the scientists are going to wake up and go, what’s going on?”
Andrew Ingersoll, professor emeritus of planetary sciences at the California Institute of Technology, agreed with that assessment.
“Earth’s rotation varies by milliseconds for many reasons,” he wrote in an email to the AP. “None of them is cause for concern.”
A slight increase in rotation speed doesn’t mean that the days are going by noticeably faster either. Merkovitz explained that standard time was once determined by how long it took the Earth to spin once on its axis—broadly understood as 24 hours. However, this number can vary by milliseconds as this speed varies slightly.
In the 1960s, scientists began working with atomic clocks to measure time more accurately. Merkovitz said that the official length of a day, scientifically speaking, now compares one complete rotation of the Earth to the time taken by atomic clocks. If these measurements are too synchronized, the International Geostationary and Reference Systems Service, an organization that keeps global time, can correct the discrepancy by adding a leap second.
Some engineers oppose the use of the leap second because it can cause large-scale and disruptive technological problems. Meta engineers Oleg Obleukhov and Ahmet Byagovi wrote a blog post about it for Meta, which supports an industry-wide effort to end the future implementation of leap seconds.
They told CBS News that “second control with negative bounce has long been supported, and companies like Meta often run simulations of this phenomenon.” “However, this has never been tested on a large scale and is likely to cause unexpected and devastating outages around the world.”
According to Yehuda Levy, a physicist at the Time and Frequency Division of the National Institute of Standards and Technology, despite a recent decrease in the length of a day in the past few years, days are actually getting longer over several centuries. He added that the current trend was not predicted, but agreed that there was nothing to worry about.
Many variables affect Earth’s rotation, such as the effects of other planets or the Moon, as well as how the Earth’s mass distributes itself. For example, according to Merkowitz, the melting of ice sheets or weather events that create a denser atmosphere.
Merkovitz says that an event that would move enough mass to affect Earth’s rotation in a way that humans perceive would be something catastrophic, like a giant meteor hitting the planet.
Caitlin O’Kane contributed to this report.
