On June 29, the Earth really save your shortest day Since the atomic clock standard was adopted in 1970 — less than 1.59 milliseconds in 24 hours — scientists say it’s a normal fluctuation.
Still, news of the faster rotation led to misleading posts on social media about the importance of measurement, prompting some to voice their concerns about the consequences.
“They’ve reported that the world is spinning faster, this seems like it should be bigger news,” said a tweet that was shared nearly 35,000 times. “At this point we’ve become so insensitive to disaster that it’s like what’s next.”
Some Twitter users responded to these tweets with jokes and skepticism about the magnitude of the measurement. But others have expressed concerns about how it will affect them.
But scientists told the AP that Earth’s rotational speed is constantly fluctuating, and the record-breaking measurement isn’t cause for panic.
“It’s totally normal,” said Stephen Merkowitz, 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 scientists wake up, what’s going on?”
Andrew Ingersoll, professor emeritus of planetary science at the California Institute of Technology, agreed with this assessment.
“Earth’s rotation varies between milliseconds for many reasons,” he wrote to the AP in an email. “None of them are cause for concern.”
Nor does the slight increase in rotational speed mean that the days pass noticeably faster. Merkowitz explained that standardized time was determined by how long it once took the Earth to spin around its axis once—commonly understood as 24 hours. However, as this speed fluctuates slightly, this number may vary in milliseconds.
In the 1960s, scientists began working with atomic clocks to measure time more accurately. Merkowitz said that scientifically speaking, the official length of a day now compares the speed of one full rotation of the Earth to the time it takes atomic clocks. If these measurements get out of sync too much, the International Earth Rotation and Reference Systems Service, an organization that maintains the global time, can correct the discrepancy by adding a leap second.
Some engineers oppose introducing leap seconds because it can cause large-scale and devastating technical problems. Meta engineers Oleg Obleukhov and Ahmad Byagowi wrote a blog post for Meta supporting an industry-wide effort to stop future promotions of leap seconds.
“Negative leap second management has long been supported, and companies like Meta often run simulations of this event,” he told CBS News. “However, it has never been validated on a large scale and will likely lead to unpredictable and devastating disruptions worldwide.”
Despite recent declines in day length over the past few years, days have actually gotten longer for several centuries, according to Judah Levine, a physicist in the Time and Frequency Division of the National Institute of Standards and Technology. He added that the current trend was not predicted, but acknowledged that it was nothing to worry about.
Many variables affect the Earth’s rotation, such as influences from other planets or the moon, and how Earth’s mass redistributes itself. For example, melting ice sheets or weather events that create a denser atmosphere, according to Merkowitz.
However, Merkowitz said that the kind of event that would move enough mass to affect the Earth’s rotation in a way that is perceptible to humans would be something of a dreadful one, such as the planet being hit by a giant meteor.
Caitlin O’Kane contributed to this report.