Curious.... I saw this pic just a couple days ago:
![[Image: 21370985_1654439247961206_90494055320114...e=5A566830]](https://scontent.flis8-1.fna.fbcdn.net/v/t1.0-9/21370985_1654439247961206_9049405532011451640_n.jpg?oh=7b43c8e8252d34dfad7a7dc71f402af8&oe=5A566830)
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This view from the Cassini spacecraft shows a wave structure in Saturn's rings known as the Janus 2:1 spiral density wave. Resulting from the same process that creates spiral galaxies, spiral density waves in Saturn’s rings are much more tightly wound. In this case, every second wave crest is actually the same spiral arm which has encircled the entire planet multiple times. At this location, ring particles orbit Saturn twice for every time the moon Janus orbits once, creating an orbital resonance. The wave propagates outward from the resonance (and away from Saturn), toward upper-left in this view. The small, bright spots in the image are places where radiation or cosmic rays have interfered with the camera sensor. This image was taken on June 4, 2017.
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May Cassini's pics keep bringing us wonderful new sights!
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This view from the Cassini spacecraft shows a wave structure in Saturn's rings known as the Janus 2:1 spiral density wave. Resulting from the same process that creates spiral galaxies, spiral density waves in Saturn’s rings are much more tightly wound. In this case, every second wave crest is actually the same spiral arm which has encircled the entire planet multiple times. At this location, ring particles orbit Saturn twice for every time the moon Janus orbits once, creating an orbital resonance. The wave propagates outward from the resonance (and away from Saturn), toward upper-left in this view. The small, bright spots in the image are places where radiation or cosmic rays have interfered with the camera sensor. This image was taken on June 4, 2017.
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May Cassini's pics keep bringing us wonderful new sights!
