The Cassini Saturn probe is nearing the end of its life. And NASA is sending it out in the best way possible, with increasingly close passes of the ring plane. They’re getting some fine imagery out of the process. The image below is a closeup of the A ring showing density waves caused by the moons Janus and Epimetheus. There are also a lot of little artifacts in the image… specks and streaks, caused by cosmic rays smacking into the CCD during imaging.