Stars over Sisters

The constellation of Capricornus the sea-goat is best seen during the early evening in September. Follow a straight line from the star Vega through Altair (two members of the Summer Triangle) and you will come to this arrowhead-shaped constellation low in the southern sky.

The Greeks associated Capricornus with Pan, the god of nature. In Greek mythology, Pan was about to be attacked by the monster Typhon. To save himself from being found, he transformed himself into a goat and then jumped into the Nile River. After a bit of time, the submerged parts of his body transformed into a fish from the waist down, making him half goat, half fish.

Within Capricornus is found the fine globular cluster M30. This ball of older stars is 30,000 light-years away and about 93 light-years across. With a dense core, it is easily visible through a pair of binoculars.

There is also a group galaxies located in Capricornus. Called HCG 87, there are at least three galaxies grouped together. HCG stands for Hickson Compact Group, a catalog of galaxy groups published by Paul Hickson in 1982. HCG 87 contains an elliptical galaxy, a face-on spiral galaxy, and an edge-on spiral galaxy. A face-on spiral galaxy is one that presents a polar aspect to the observer, allowing us to see the spiral, while an edge-on spiral galaxy is viewed in line with its equator, allowing us to simply see the side.

This year, the autumnal equinox occurs on September 22 at 1:45 p.m. PDT, signaling the start of fall here in the northern hemisphere. Although it brings the shorter days distinctive of autumn, when the sun is directly over the equator headed to the southern hemisphere, day and night are approximately of equal length.

Venus, still glowing in the western sky, sets just after twilight. Saturn begins the month setting around 9 p.m., but by month's end is setting at twilight as well, so be sure to catch the pair early in the evening. The two planets are closest together on September 17.

Jupiter rises around midnight on average for the month, while Mars comes up at about 3 a.m. Both planets are easily viewed in the eastern sky until dawn.

To view Uranus, grab a pair of binoculars. Located in the constellation of Pisces, now is the best time to view the third largest planet in our solar system. It is currently at its brightest and visible nearly all night long.

The moon is new on September 5, first quarter on September 12, full on September 19, and last quarter on September 26. On Friday, September 6, there will be a Stars Over Sisters public star watch at the Sisters Park & Recreation District building, located adjacent to Sisters High School. A pre-star-watch presentation will begin at 8:30 p.m. Following the talk, all are invited to view the night sky through telescopes that will be set up, courtesy of the Sisters Astronomy Club.

For information about Sisters Astronomy Club activities and events, visit www.sistersastronomyclub.org.