PARIS - Jupiter’s tempestuous, gassy atmosphere stretches some 3,000 kilometres (1,860 miles) deep and comprises a hundredth of the planet’s mass, studies based on observations by NASA’s Juno spacecraft revealed Wednesday.

The measurements shed the first light on what goes on beneath the surface of the largest planet in the Solar System, which from a distance resembles a colourful, striped glass marble.

“Galileo viewed the stripes on Jupiter more than 400 years ago. Until now, we only had a superficial understanding of them,” said Yohai Kaspi from the Weizmann Institute of Science in Israel, an author of one of four studies published in Nature.

Up to a depth of about 3,000 km, Juno’s data showed, Jupiter comprises a psychedelic swirl of cloud bands and jet streams blown by powerful winds, in opposite directions and at different speeds.

But underneath, the planet’s liquid core of hydrogen and helium rotates uniformly, behaving almost like a solid body, researchers found.

“The result is a surprise because this indicates that the atmosphere of Jupiter is massive and extends much deeper than we previously expected,” Kaspi told AFP.