Figure: Two waves in one, Saturn's A ring

This is a narrow-angle camera image of Saturn's rings taken after the successful completion of the orbit insertion burn. At this time Cassini-Huygens viewed the rings from the north side. The Sun illuminates the rings from the south side.

This image was taken in the middle part of the A ring. The image shows the Prometheus 12:11 density wave in the lower left part of the image and the Mimas 5:3 bending wave in the middle of the image. The pixel scale of this image is about 290 metres per pixel.

Credit: NASA/JPL/Space Science Institute

http://www.esa.int/esa-mmg/mmg.pl?b=b&keyword=density%20wave&single=y&start=2