Cassini’s ring dive offers first close-up of Saturn’s cloud tops

Cassini has beamed back stunning images from the spacecraft’s daring dive between Saturn and its rings.

The first closeup pictures of the planet’s atmosphere reveal peculiar threadlike clouds and puffy cumulus ones, plus the giant hurricane first spotted on Saturn in 2008 (SN: 11/8/08, p. 9). Released April 27, the images of Saturn’s cloud tops are a “big step forward” for understanding the planet’s atmosphere, says Cassini imaging team member Andy Ingersoll, an atmospheric scientist at Caltech.

“I was pretty struck by the prevalence of the filamentary type of clouds,” he says. “It’s as if the long threads of clouds refuse to mix with each other.” Studying the interactions of these clouds and the cumulus ones will reveal what’s going on in Saturn’s skies.

During its dive, Cassini swooped to within 3,000 kilometers of the planet’s atmosphere and 300 kilometers of the innermost edge of the rings at 124,000 kilometers per hour. Slamming into even tiny particles from the rings could have damaged the spacecraft. To protect Cassini, mission scientists used the spacecraft’s 4-meter-wide antenna as a shield, putting the spacecraft temporarily out of contact with NASA.

Cassini reestablished contact with mission control early on April 27 and started to send back data minutes later. Shots of the rings and other features will be available in the coming days, and more stunning views are expected when the spacecraft shoots through the gap between Saturn and its rings again on May 2. It will ultimately orbit 20 more times before plunging into the planet’s atmosphere on September 15 (SN Online: 4/21/17).