The Cassini spacecraft is a victim of its own success. It astonished scientists by finding conditions potentially suitable for life beneath the surface of one of Saturn's icy moons, Enceladus.
When Cassini runs out of fuel it could accidentally crash into this pristine world, spreading earthly contamination. So researchers decided that the spacecraft must be destroyed. That's why, on Friday, it will slam itself into Saturn's atmosphere.
It's a dramatic end to an impressive career. For over a decade, Cassini has orbited around Saturn 294 times, collected more than 600 GB of data, visited over a dozen moons and discovered at least seven new ones. It has sent over 400,000 images back home.
Skunk Bear, NPR's science video channel, has stitched together thousands of those photos to showcase some beautiful (and often weird) scenes from our solar system.