In ‘grand finale,’ Cassini spacecraft sets off on collision course with Saturn

Cassini and Saturn

DEEP DIVE  The Cassini spacecraft will explore the uncharted territory between Saturn and its rings (shown in this artist’s illustration) before plunging into the planet’s atmosphere in September.

JPL-Caltech/NASA

View the animation

Cassini is bravely going where no spacecraft has gone before — between Saturn and its rings.

The probe, which launched in 1997 and has orbited Saturn since 2004, starts this daring expedition April 22. It will fly through the 2,400-kilometer-wide gap between Saturn and its rings 22 times before plunging into the planet’s atmosphere and burning up on Sept. 15.

Mission scientists designed this dramatic end for the spacecraft to protect Saturn’s moons Titan and Enceladus from being contaminated with any surviving biological material from Earth. Cassini is running low on fuel and once it is gone, the team will no longer have control of the probe. Intentionally slamming Cassini into Saturn will prevent it from accidentally crashing into the moons.

Called Cassini’s “grand finale,” these last scientific endeavors could provide new clues to the make-up of the planet’s rings and where they originated, what the planet’s clouds look like and how fast the giant ball of gas spins. The spacecraft will beam this data back to Earth as it swoops around Saturn, into its skies and then falls silent forever.

LOOP-DE-LOOP In Cassini’s last act, the spacecraft will whiz 22 times between Saturn and its rings. This animation illustrates the spacecraft’s final orbits. Erick Sturm/Jet Propulsion Laboratory – Caltech/NASA

Ashley Yeager is the associate news editor at Science News. She has worked at The Scientist, the Simons Foundation, Duke University and the W.M. Keck Observatory, and was the web producer for Science News from 2013 to 2015. She has a bachelor’s degree in journalism from the University of Tennessee, Knoxville, and a master’s degree in science writing from MIT.