The probe is embarking on a slow spiral into Saturn

For the last 13 years, a NASA spacecraft the size of a school bus has been whirling around Saturn, collecting data and snapping mesmerizing images of the ringed planet and its icy moons. That vehicle is Cassini, and its exploration of Saturn has led to some of the biggest discoveries ever made about the worlds in our Solar System. But as accomplished as this spacecraft is, it's time for its life to end: this weekend, Cassini will change course and embark on a new path around Saturn — one that will eventually lead to the probe's destruction.

Cassini's demise is an important part of NASA's mission plan. After all this time, the vehicle is running low on fuel, which means NASA will eventually lose the ability to maneuver it. And the agency doesn't want to risk Cassini going somewhere it shouldn't