So long, Saturn

Cassini's Final Image: NASA/JPL

LAST SHOT: I awoke at about 4:20 this morning, and there was no going back to sleep. I knew that at that moment, NASA's Cassini probe was in the last 30 minutes of its service life, headed on a course to vaporize in Saturn's atmosphere, becoming one with the planet it had given Earthlings such amazing vantage points of our lovely, ringed neighbor since 2004. 

NASA TV coverage showed antennae around the world trying to make contact with Cassini until the end. Loss of contact with the Cassini spacecraft occurred at 4:55 a.m. PDT, with the signal received by NASA's Deep Space Network antenna complex in Canberra, Australia.

Listening to Mission Control, we heard the moment when Cassini's thrusters started fighting back (valiantly but ineffectively) against the pull of Saturn's gravity. 

It was poignant watching the scientists celebrate the end of such a successful mission.

     Photo Credit: (NASA/Joel Kowsky)

In the photo above, Cassini program manager at JPL, Earl Maize, left, and spacecraft operations team manager for the Cassini mission at Saturn, Julie Webster embrace after the Cassini spacecraft plunged into Saturn, at NASA's Jet Propulsion Laboratory in Pasadena, California. Since its arrival in 2004, the Cassini-Huygens mission has performed nearly flawlessly, vastly expanding our knowledge of Saturn and its moons, and captivating the world with amazing data and images. 

Watching the post-finale coverage, we heard one big takeaway from the Cassini mission. JPL Director Mike Watkins said the "discoveries are so compelling (from Cassini), we'll go back." That's the hallmark of a successful probe, isn't it? "We'll go back and look at those ocean worlds in great detail," he predicted.

In a press release, Watkins was quoted as saying, "It's a bittersweet, but fond, farewell to a mission that leaves behind an incredible wealth of discoveries that have changed our view of Saturn and our solar system, and will continue to shape future missions and research." 

More from a post-mission press release: 

As planned, data from eight of Cassini's science instruments was beamed back to Earth. Mission scientists will examine the spacecraft's final observations in the coming weeks for new insights about Saturn, including hints about the planet's formation and evolution, and processes occurring in its atmosphere.

"Things never will be quite the same for those of us on the Cassini team now that the spacecraft is no longer flying," said Linda Spilker, Cassini project scientist at JPL. "But, we take comfort knowing that every time we look up at Saturn in the night sky, part of Cassini will be there, too."

Cassini launched in 1997 from Cape Canaveral Air Force Station in Florida and arrived at Saturn in 2004. NASA extended its mission twice - first for two years, and then for seven more. The second mission extension provided dozens of flybys of the planet's icy moons, using the spacecraft's remaining rocket propellant along the way. Cassini finished its tour of the Saturn system with its Grand Finale, capped by Friday's intentional plunge into the planet to ensure Saturn's moons - particularly Enceladus, with its subsurface ocean and signs of hydrothermal activity - remain pristine for future exploration.

While the Cassini spacecraft is gone, its enormous collection of data about Saturn - the giant planet, its magnetosphere, rings and moons - will continue to yield new discoveries for decades to come.

"Cassini may be gone, but its scientific bounty will keep us occupied for many years," Spilker said. "We've only scratched the surface of what we can learn from the mountain of data it has sent back over its lifetime."

An online toolkit with information and resources for Cassini's Grand Finale is available at: https://saturn.jpl.nasa.gov/grandfinale

The Cassini-Huygens mission is a cooperative project of NASA, ESA (European Space Agency) and the Italian Space Agency. JPL, a division of Caltech in Pasadena, manages the mission for NASA's Science Mission Directorate in Washington.

If you would like to learn more, check out the Cassini Post-Event News Conference

http://www.ustream.tv/recorded/107948580

Participants include:

-- Thomas Zurbuchen, associate administrator for the Science Mission Directorate, NASA Headquarters, Washington
-- Michael Watkins, director, JPL
-- Earl Maize, Cassini project manager, JPL
-- Linda Spilker, Cassini project scientist, JPL
-- Julie Webster, spacecraft operations chief, JPL

And, if you want to watch Cassini's end, check out the End-Of-Mission Live Commentary broadcast. About the 50 minute mark when get to mission control for Cassini's final moments http://www.ustream.tv/recorded/107946496