It might not sound like much, considering how one day in Venus is equivalent to a whopping 243 Earth days. However, a new study suggests that an unusual weather event could cause the length of a day on our planet’s closest neighbor to change by a maximum of two minutes.
The original discovery was made by the team behind the Japanese Aerospace Exploration Agency’s Akatsuki spacecraft, which had recently spotted a “bow-like structure” in Venus’ clouds that appears stationary even as strong, fast winds blow underneath it. According to Gizmodo, the Akatsuki team believes that the structure was created when Venus’ winds blew against its mountains, much like river water can flow over large rocks.
The data was then analyzed by a multinational team of researchers that included scientists from UCLA and the University of Paris-Saclay in France, as they took Akatsuki’s findings and used computer modeling to figure out the nature of the stationary peculiarity spotted by the Japanese spacecraft. The simulation suggested that the odd atmospheric anomaly might have been a “gravity wave” that formed when Venus’ powerful winds interacted with its mountains, just as the Akatsuki team theorized. More interestingly, the model used by the researchers hinted that the waves, in concert with Venus’ dense atmosphere, could result in a day on the planet becoming shorter or longer by up to two Earth minutes.
According to Cosmos, the phenomenon observed by the researchers is similar to what we see when winds crash against our planet’s mountains, thereby changing Earth’s spin. However, that doesn’t change the length of our days that much, as this figure typically fluctuates by just a few milliseconds.
“It’s not something we can feel, but something we can measure,” said study author Thomas Navarro, a planetary scientist at UCLA.
Although two minutes is a very small change in the grand scheme of things, the researchers explained that the finding was noteworthy beyond that, as studying the gravity waves could be key in helping scientists figure out the intricacies of the Venusian atmosphere, while also providing a greater understanding of weather events on Earth.
With all that in mind, Gizmodo stressed that the researchers did not actually confirm a change in the length of a Venusian day, but rather ran a simulation that hints at that possibility. Furthermore, the researchers acknowledged that the model they used has some limits, and the only way to confirm their theory would be to directly observe what goes down in Venus once the weather phenomenon takes place.
For future studies, Navarro told Cosmos that he hopes to find out why Venus’ atmosphere “super-rotates,” or rotates faster than the planet actually does, thus resulting in conditions favorable to the creation of the aforementioned gravity waves. As noted by Cosmos, this particular phenomenon of super-rotation isn’t exactly unique, as it appears to be common in objects that rotate slowly, with Saturn’s moon Titan being another example.