Viewing Zooms in on Moon, Pulsating Star

A first-quarter moon and a pulsating variable star will be featured at this month’s free public viewing Friday, Aug. 21, beginning at 8 p.m. and lasting several hours at the Westmont Observatory. The moon will be about seven days old and there should be a number of craters to examine on its surface. The pulsating variable star, Chi Cygni, changes in brightness every 13.4 months. The best viewing generally occurs later in the evening. In case of inclement or overcast weather, please call the Telescope Viewing Hotline at (805) 565-6272 and check the Westmont website to see if the viewing has been canceled.

The Great Globular Cluster, which houses about one million stars, will also be in view this month. Saturn will be visible to the left of the moon, and the Cassini Division, the gap between Saturn’s A and B rings, should be visible.

“Stars such as Chi Cygni are known as Mira-type variable stars,” says Thomas Whittemore, Westmont physics instructor. “These are Red Giants which can expand and contract by 40 percent of their diameter. Imagine an aging star that changes in brightness every 13.4 months from invisible to the naked eye to possibly visible to the naked eye. One thing to keep in mind is that this star is 550 light-years away. Its light is coming to us from a time before Christopher Columbus set sail.”

The observatory opens its doors to the public every third Friday of the month in conjunction with the Santa Barbara Astronomical Unit, whose members bring their own telescopes to Westmont for the public to gaze through.

The Keck Telescope is housed in the observatory between Russell Carr Field and the track and field/soccer complex. Free parking is available near the baseball field.