Bob Moler's Ephemeris Blog

This is Ephemeris for Monday, August 28th. Today the Sun will be up for 13 hours and 26 minutes, setting at 8:26, and it will rise tomorrow at 7:01. The Moon, 2 days before full, will set at 4:38 tomorrow morning.

The most striking feature of the planet Saturn are its rings. It is not the only planet with rings. Jupiter Uranus and Neptune all have rings, plus some asteroids. And at least one Kuiper belt objects has rings, but Saturn has the grandest of all the ring systems. The broad rings are easily seen in small telescopes. They are labeled A, B and C, A being the outermost of the bright rings B is the center most and C is just barely seen inside the B ring. The diameter of these rings to the outside of the A ring is 150,000 miles, a bit more than the average distance from the Earth to our Moon, and a little less than 70 feet thick so when they go edge on to us as they do about every 15 or so years they completely disappear.

The astronomical event times given are for the Traverse City/Interlochen area of Michigan (EDT, UT –4 hours). They may be different for your location.

Addendum

Saturn’s rings are much more complex than what can be seen in a small telescope. Observing Saturn through a small telescope, the A and B rings are evident, though the Cassini Division, of nearly 5,000 miles in width, may be elusive. The C, or Crêpe, ring is very hard to see, and is best seen as a dusky shadowlike feature against the planet. This image of Saturn was created by Stellarium, annotations were created in LibreOffice Draw, assembled and output using GIMP.

More on Saturn’s rings tomorrow.