JPL’s Cassini Spacecraft Begins Epic Final Year Exploring Saturn

The Cassini spacecraft — which launched in 2004 on a mission managed by Pasadena’s Jet Propulsion Laboratory to explore Saturn and its many moons — will conclude its historic trip next September, but not before approaching the gas giant’s main outer rings.

Starting November 30, the spacecraft orbit 20 times around Saturn’s F ring. It will approach the center of the narrow F ring and be within 4,800 miles of it to survey its peculiar structure, according to a statement released to the media.

“During the F-ring orbits we expect to see the rings, along with the small moons and other structures embedded in them, as never before,” said Linda Spilker, Cassini’s project scientist at JPL in the media statement. “The last time we got this close to the rings was during arrival at Saturn in 2004, and we saw only their backlit side. Now we have dozens of opportunities to examine their structure at extremely high resolution on both sides.”

Cassin’s return — dubbed as the Grand Finale — begins next April with a close flyby of Saturn’s second-largest moon, Titan. The spacecraft’s orbit will be reshaped by Titan’s gravitational tug in a way will have it pass through the gap between Saturn and the rings — an unexplored area that is 1,500 miles wide, according to the press release.

“We’ve used Titan’s gravity throughout the mission to sling Cassini around the Saturn system,” said Earl Maize, Cassini project manager at JPL in the media statement. “Now Titan is coming through for us once again, providing a way for Cassini to get into these completely unexplored regions so close to the planet.”

During the Grand Finale, the probe will make the closest observations of Saturn it ever has, mapping its magnetic and gravity fields with precision and snapping close photos of the planet’s atmosphere, according to the media release.

Furthemore, scientists are hoping Cassini can analyze the planet’s interior structure and the mass of rings, finally ending the question of how old they are. According to the press release, the craft will also sample the outer reaches of Saturn’s atmosphere, something that has never been done before.

“It’s like getting a whole new mission,” said Spilker in the media statement. “The scientific value of the F ring and Grand Finale orbits is so compelling that you could imagine a whole mission to Saturn designed around what we’re about to do.”

The Grand Finale is slated to end on September 15, 2017 as Cassini will take dive into Saturn’s atmosphere, sending back data on the gas giant’s chemical composition until its signal is completely lost.

“We may be counting down, but no one should count Cassini out yet,” said Curt Niebur, Cassini program scientist at NASA Headquarters in Washington in the statement. “The journey ahead is going to be a truly thrilling ride.”