Even when viewed through a typical amateur telescope, Saturn’s rings offer a jaw-dropping spectacle that always satisfies. But looked at through the eyes of NASA’s now-departed Cassini spacecraft, the view is unlike anything else in the solar system, a stunning tapestry of mind-boggling complexity. This image, taken on 22 August, 2009, by Cassini’s narrow-angle camera at a distance of 2 million kilometres (1.27 million miles) employed red, green and blue filters to produce a natural colour view. The rings are made up mostly of water ice, with particles as small as grains of sand and as large as mountains. The precise nature of the icy material that gives the rings their colour remains a topic of debate.
As dusk fades to dark on Saturday, 22 August, observers in the British Isles and Western Europe with clear skies can see the first quarter Moon close above planet Saturn low to the southwest. But for those skywatchers with binoculars and small telescopes, an additional treat is in store as the Moon passes in front of (occults) a naked-eye star.