The final approach of the $4 billion spacecraft towards Saturn's Atmosphere

Posted September 14, 2017

On Monday, the Cassini probe flew past Saturn's huge moon Titan one last time for a gravity assist - a final kiss goodbye, as NASA calls it - nudging the spacecraft into a death dive.

"You showed us Saturn's rings, and lots of pretty things".

They provided the probe's senses for studying the dust, gas and magnetic fields around Saturn and its moons as well as capturing optical and radar images at visible and invisible wavelengths.

It will be possible, but hard, to observe Cassini's death from Earth, due to the spacecraft's small size and the position of Saturn in the sky. It will then burn up like a meteor in about two minutes while still hundreds of miles above the clouds.

The Cassini-Huygens mission is a joint endeavour of Nasa, and the European and Italian space agencies.

"The Cassini mission has been packed full of scientific firsts, and our unique planetary revelations will continue to the very end of the mission as Cassini becomes Saturn's first planetary probe, sampling Saturn's atmosphere up until the last second", said Linda Spilker, Cassini project scientist at NASA's Jet Propulsion Laboratory in Pasadena, California. Captured by NASA's Cassini mission on July 19, 2013.

And the spacecraft itself, as well as its instruments, are informing future missions that NASA has planned, like NASA's Europa Clipper mission to explore Jupiter's icy moon, launching in the 2020s. Bringing an end to its epic 13-year mission, the reliable craft is now just hours away from slamming into Saturn's atmosphere and bringing its existence to a fiery end. For example it discovered that Saturn has two belts (the main and the new), which are interrupted by its rings.

Cassini gazed toward the northern hemisphere of Saturn to spy subtle, multi-hued bands in the clouds there.

The Canberra Deep Space Complex is assisting with the mission.

Scientists were especially interested in Saturn's giant moon Titan, which has a nitrogen and methane atmosphere and in some ways resembles an early version of Earth. It was the first ever touchdown on an alien world beyond the asteroid belt. On Earth, such vents are havens for life.

According to NASA, this final flyby of Titan was also Cassini's closest one as the spacecraft lowered to just 73,974 miles above the moon's surface. Cassini also carried the Huygens probe, which landed on Titan, Saturn's largest moon, in 2005 and sent data about the moon's surface and atmosphere to Cassini for 72 minutes before the signal was interrupted by the horizon.

The Cassini mission, which arrived at the Saturn system in 2004, has been extended twice and will finally use up the last of its rocket propellant this week. It has already produced 3,948 research papers, but scientists will ponder the data for years to come.

How did scientists communicate with Cassini? One question the probe may answer on its death plunge is how old the rings are. Most likely, that final signal will be data-only, Staab said. "What would it look like if I could hold a ring particle in my hand?"