A mysterious structure has appeared on Venus
A bow-shaped structure which spanned almost 10,000 kilometres across Venus appeared for several days after a Japanese probe arrived at Earth’s nearest neighbour in 2015 and then vanished almost as soon as it came about.
The scientists behind the Japanese probe Akatsuki believe that the large structure could be evidence of the biggest gravity wave – not to be confused with the recently discovered gravitational waves – ever seen in the solar system.
However, what is confusing the experts is that they believe that gravity waves – which was found 65 kilometres above the surface – could not form so high up in the atmosphere of a planet.
Over the course of a four day period, the structure, which stretched all the way from the north to the south pole of the planet, maintained its position despite being bombarded by 359 kilometre per hour winds.
The huge structure
As such, the team say that the evidence is pointing towards gravity waves.
Gravity waves occur on planets, even Earth. The phenomenon happens when there is a disturbance in the planet’s atmosphere.
Nasa demonstrating how a gravity wave might occur on Venus
If, for example, it is a gravity wave on Venus, then the experts suspect that it happened when the zooming wind was pushed up into the sky after it hit mountain ranges, which is then countered by the gravity which is trying to push it down again.
Gravitational waves, which were discovered last year, on the other hand are ripples in spacetime.
Venus is the nearest planet to Earth
The team wrote in their paper published in Nature Geoscience: "The present study shows direct evidence of the existence of stationary gravity waves, and it further shows that such stationary gravity waves can have a very large scale - perhaps the greatest ever observed in the Solar System.”
One of the researchers, Makoto Taguchi from Rikkyo University, told Wired: "We suppose that highlands are a key to generating the stationary gravity waves, because most of the bows - and we have found more than 15 bows so far - have appeared above the highlands at their centres.”