Astronomers have been trying to discover new data on the speed Saturn turns on its axis. This is no easy feat, owing to the nearly impossible to penetrate gaseous atmosphere that covers the planet. But thanks to their new results, they suggest that the figures written in textbooks need to be corrected.
Their new data shows that Saturn’s period of one rotation, which is equivalent to a day on earth, is actually 6 minutes shorter than what is written in the current textbooks about the solar system.
The difference of 6 minutes may not sound big enough to consider such a wide change, yet that number will affect how scientists calculate how the planet’s atmosphere blows, according to Ravit Helled, a planetary scientist at Tel Aviv University in Israel.
“We used to think that we knew the rotation period, considered a basic property of any planet” she says.
As she recalls in past studies, there was a disagreement between the data the Voyager spacecraft took when it flew past Saturn in the early 1980s and came up with 10 hours and 39 minutes, and the Cassini spacecraft, which traveled around the planet in 2004 and recorded a different figure: 10 hours and 47 minutes.
“Since then, there has been this big open question concerning Saturn’s rotation period,” says Helled. “In the last few years, there have been different theoretical attempts to pin down an answer.”
Helled’s latest findings on Saturn’s period of one rotation together with her team of researchers came up with a number 6 minutes faster than that of Voyager’s data results. Using Saturn’s magnetic field to conclude its spin rate, it came up with 10 hours and 32 minutes.
6 minutes may not sound too alarmingly far from the previous data, but it makes a big difference since it implies that Saturn’s equator atmosphere is spinning 250 miles faster than previously assumed from the Voyager figure.
The Voyager figure shows that winds were blowing in one direction while the new result actually says the wind blows about half to the west and half to the east.
“The rotation period of a giant planet is a fundamental physical property, and its value affects many aspects of the physics of these planets, including their interior structure and atmospheric dynamics,” she says.