Cassini Makes its ‘Goodbye Kiss’ Flyby of Titan

Updated at 9:45 p.m. PDT on Sept. 12, 2017

Cassini is back in contact with Earth following its distant
flyby of Titan, and data are streaming in. As planned, ground
controllers made contact with the spacecraft at 6:19 p.m. PDT.

NASA’s Cassini spacecraft is headed toward its Sept. 15 plunge
into Saturn, following a final, distant flyby of the planet’s
giant moon Titan.

The spacecraft made its closest approach to Titan today at
12:04 p.m. PDT (3:04 p.m. EDT), at an altitude of 73,974 miles
(119,049 kilometers) above the moon’s surface. The spacecraft
is scheduled to make contact with Earth on Sept. 12 at about
6:19 p.m. PDT (9:19 p.m. EDT). Images and other science data
taken during the encounter are expected to begin streaming to
Earth soon after. Navigators will analyze the spacecraft’s
trajectory following this downlink to confirm that Cassini is
precisely on course to dive into Saturn at the planned time,
location and altitude.

This distant encounter is referred to informally as “the
goodbye kiss” by mission engineers, because it provides a
gravitational nudge that sends the spacecraft toward its
dramatic ending in Saturn’s upper atmosphere. The geometry of
the flyby causes Cassini to slow down slightly in its orbit
around Saturn. This lowers the altitude of its flight over the
planet so that the spacecraft goes too deep into Saturn’s
atmosphere to survive, because friction with the atmosphere
will cause Cassini to burn up.

Cassini has made hundreds of passes over Titan during its
13-year tour of the Saturn system — including 127 precisely
targeted encounters — some at close range and some, like this
one, more distant.

“Cassini has been in a long-term relationship with Titan, with
a new rendezvous nearly every month for more than a decade,”
said Cassini Project Manager Earl Maize at NASA’s Jet
Propulsion Laboratory in Pasadena, California. “This final
encounter is something of a bittersweet goodbye, but as it has
done throughout the mission, Titan’s gravity is once again
sending Cassini where we need it to go.”

Cassini is ending its 13-year tour of the Saturn system with an
intentional plunge into the planet to ensure Saturn’s moons —
in particular Enceladus, with its subsurface ocean and signs of
hydrothermal activity — remain pristine for future
exploration. The spacecraft’s fateful dive is the final beat in
the mission’s Grand Finale, 22 weekly dives (begun in late
April) through the gap between Saturn and its rings. No
spacecraft has ever ventured so close to the planet before.

An online toolkit of information and resources about Cassini’s
Grand Finale and final plunge into Saturn is available at:

The Cassini spacecraft was launched in 1997 and arrived at
Saturn in 2004. During its time there, Cassini has made

numerous dramatic discoveries
, including a global ocean
with indications of hydrothermal activity within the icy moon
Enceladus, and liquid methane seas on another moon, Titan.

The Cassini-Huygens mission is a cooperative project of NASA,
ESA (European Space Agency) and the Italian Space Agency.
NASA’s Jet Propulsion Laboratory, a division of Caltech in
Pasadena, manages the mission for NASA’s Science Mission
Directorate, Washington. JPL designed, developed and assembled
the Cassini orbiter.

More information about Cassini:

News Media Contact

Preston Dyches
Jet Propulsion Laboratory, Pasadena, Calif.