Why did Jupiter change colours? Mystery of its famous stripes solved
Jupiter is known for its mysterious colours, raging storms and sheer size which make it a giant among the planets in our Solar System. For decades scientists have been wondering about another aspect of this planet — its changing stripes.
Astronomers have observed and pondered over bands of colours that are often seen to move and change. They had not known what drove this change until now.
A team of researchers have now revealed that this could be due to churning on the planet that makes its magnetic field go crazy.
The stripes are seen around the equator along lines of latitude and the colours of these belts change randomly. The colour change reveals the change in the weather on the planet. "The colours of the belts can change and sometimes the whole weather pattern goes slightly crazy, and it has been a mystery as to why that happens," Professor Chris Jones, University of Leeds School of Maths, said in a statement.
The study published in the journal Nature Astronomy took data from observations of the planet by Nasa's Juno spacecraft.
Astronomers from the University of Leeds have shown that the variation in colours could in turn be caused by waves produced by the planet's magnetic field, deep within its interior. It happens about 50 kilometers below the gas giant's surface. The team has now calculated changes in the giant's magnetic field.
"Every four or five years, things change. The colours of the belts can change and sometimes you see global upheavals when the whole weather pattern goes slightly crazy for a bit, and it has been a mystery as to why that happens," Professor Jones said.
The team looked at the magnetic field stretching over several years and was able to track its waves and oscillations and have even been able to follow a specific spot of magnetic field on Jupiter called the Great Blue Spot. This spot has been moving eastwards, but the latest data shows that movement is slowing – leading the Juno team to believe this is the beginning of an oscillation.
Torsional oscillations are wavelike motions in a planetary magnetic field.
"I hope our paper could also open a window to probe the hidden deep interior of Jupiter, just like seismology does for the Earth and helioseismology does for the Sun," Professor Jones added.