Moon waves and wakes

010217 saturnring 1
NASA / JPL-Caltech / Space Science Institute

This Cassini image features a density wave in Saturn’s A ring (left) that lies around 134,500 kilometres from Saturn. Density waves are accumulations of particles at certain distances from the planet.

This feature is filled with clumpy perturbations, which researchers informally refer to as “straw.” The wave itself is created by the gravity of the moons Janus and Epimetheus, which share the same orbit around Saturn. Elsewhere, the scene is dominated by “wakes” from a recent pass of the ring moon Pan.

The image was taken in visible light with the Cassini spacecraft wide-angle camera on 18 December 2016. The view was obtained at a distance of approximately 56,000 kilometres from the rings and looks towards the unilluminated side of the rings.

Please login to favourite this article.