The Earth recently broke its own record. Our planet completed a single rotation in the shortest span ever recorded on June 29, 2022. The Earth takes just under 24 hours to complete one rotation around its axis, the exact time is 23 hours, 56 minutes and 4.09053 seconds. This is known as a sidereal day.
A solar day is defined as the time taken for the Sun to appear in the same location in the sky. The Earth had its shortest solar day ever recorded on June 29, when it completed its rotation in 1.50 milliseconds less than 24 hours. The record was almost broken again this month when Earth completed its rotation in 1.47 milliseconds less than 24 hours on July 26.
In 2020, scientists made a surprising new discovery – the Earth’s spin was speeding up even though the planet’s rotation is gradually slowing down over the course of centuries and millennia. On July 19, Earth had broken the record of the shortest solar day that clocked in at 1.47 milliseconds under 24 hours and also recorded the shortest month that has ever been measured.
Scientists are unsure of the reason behind this apparent acceleration. When observed over large periods of time, the Earth’s rotation is slowing down by a few milliseconds every century or so. Over millions of years, this translates into a day being a couple of hours longer. The dinosaurs that lived 150 million years ago probably saw a solar day that was 23 hours long.
But the current speed up may have more concerning consequences in the short time. If the solar days get shorter, negative leap seconds may be added to clocks to keep them in line with the duration of the day. But doing so may put our computers, digital devices and IT systems at risk.
“While the leap second might have been an acceptable solution in 1972, when it made both the scientific community and the telecom industry happy, these days UTC is equally bad for both digital applications and scientists…,” wrote Facebook-parent Meta in a recent blog post.
“Introducing new leap seconds is a risky practice that does more harm than good, and we believe it is time to introduce new technologies to replace it,” the company added.
Apart from Meta, major tech giants like Amazon, Google, and Microsoft along with national organisations like the US National Institute of Standards and Technology (NIST) and France’s Bureau International des Poids et Mesures (BIPM) recently cautioned against the addition of leap and negative leap seconds.
The discrepancy in the internal and device clocks due to the addition of negative leap seconds can result in disruptions in software applications as well as hardware. The addition of leap seconds was behind outages like the ones seen by social-aggregator platform Reddit in 2012 and Cloudflare, reported the Independent.
(Edited by : Sudarsanan Mani)