NASA releases new findings about Saturn
Although NASA's Cassini spacecraft is no more after diving into Saturn's atmosphere, the wealth of data it gathered during its long life is continuing to throw up fresh findings about the planet and its icy rings.
Among the latest insights are stunning views taken by Cassini's cameras during its Grand Finale which show the rings emerging from behind the planet's hazy limb, as well as a panoramic view outward across the ringscape. Researchers have also been able to see an astonishing number of tiny propellers in the last images of the rings. These are gaps in the ring system caused by small objects known as moonlets, that can be up to 500-metres in diameter.
Cassini has also sniffed out the gasses in the space between the planet and the rings, using its Ion and Neutral Mass Spectrometer (INMS). For the first time, scientists have direct measurements of the components in Saturn's upper atmosphere, and NASA says it has allowed the team to see evidence that molecules from the rings are raining down. The INMS has detected methane within the rings of Saturn's atmosphere, too, which scientists didn't expect to find in such great abundance.
Meanwhile, members of Cassini's Magnetometer team from Imperial College London are excited that the sensitivity of the spacecraft's magnetic field measurements quadrupled during its 22 Grand Finale orbits. They are now hoping to be able to detect whether the planet has a tilt greater than 0.016 degrees, which would help them figure out the precise length of the planet's day.
Such insights were highlighted at a NASA news conference where it was also revealed that a modelling study had suggested the outward creep of Saturn's bright, so-called A-ring was being kept in check by a confederation of moons. Separately, a team of UCLA scientists have found that the largest of Saturn's 60 moons, Titan, has rainstorms that are more intense than previously thought.
These storms are said to involve liquid methane rather than water, but they create massive floods in Titan's desert terrain. “The most intense methane storms in our climate model dump at least a foot of rain a day, which comes close to what we saw in Houston from Hurricane Harvey this summer,” says Jonathan Mitchell, the principal investigator of the University of California, Los Angeles’ Titan climate modelling research group.
Data captured by Cassini before it plunged into the ringed planet’s atmosphere has given scientists fresh insights