HST Saturn 2004
Saturn as imaged by the Hubble Space Telescope. (NASA, ESA and E. Karkoschka, University of Arizona)

A Guide to Observing Saturn

Saturn is one of the showpieces of the night sky. As anyone who has viewed the ringed planet through a telescope can attest, its beauty is almost hypnotizing.

The rings of Saturn can be seen even at low power through a small telescope. Although hundreds of individual rings have been detected by spacecraft, only three components can be observed from Earth — the A, B and C rings.

The A and B rings are easily seen in most telescopes and are separated by Cassini’s division, a gap as wide as the United States. Although it appears as black as the surrounding sky of Saturn, it is actually a region of less densely packed particles. The inner C ring is not nearly as bright as the outer A and B rings and requires a 6-inch or larger telescope and an experienced eye to discern it.

Saturn labels
Saturn’s main telescopic features. (Darryl Archer)

Over a period of 15 years, the orientation of Saturn’s rings changes from edge-on (when they’re briefly invisible) to fully inclined (when they’re most spectacular), and then back to edge-on again. In 2015 the rings are tilted 24 degrees and will be at their maximum again in 2017 when they will be inclined 27 degrees.

Kwon-Saturn ring sequence
Ontario imager Andrew Kwon recorded this sequence of images showing the changing orientation of Saturn’s rings.

During nights of good seeing, observers may be able to detect subtle colour variations in the bands on the surface of Saturn, most often seen in the equatorial zone. Another interesting feature to look for is the shadow of the planet cast upon the rings, which you can see before and after the planet is at opposition.

Remember to be patient while observing the planets. Brief glimpses of subtle detail may pop into view for only a fraction of a second, but that moment may provide you with a wealth of visible detail. Seeing detail on the planets requires an observer to spend time at the eyepiece. Your eye will become trained to see more detail after a few observing sessions, and the more you look, the more you’ll see.