Fall is just around the corner.
The autumnal equinox occurs at 3:20 p.m. Sept. 22. Cool nights are here already, and cold nights aren't that far off. Right now is a wonderful time to enjoy the night sky, especially right after twilight ends.
Great examples of three types of deep-space objects are ideally positioned for telescopic viewing after dark in September, and they are not far apart:
- Double star: Albireo in the constellation Cygnus.
- Globular cluster: the Great Cluster in Hercules.
- Galaxy: Andromeda in, of all things, Andromeda.
Even if you're familiar with these objects, you're unlikely to be disappointed by another look. If you get a chance, invite someone else to have a look, too.
Evening stargazers won't have to look hard to find Jupiter, the brightest natural object in the night sky other than our moon. Shining at magnitude minus 2.7, it's situated in Capricornus. Jupiter rises around 6:30 p.m. and sets around 5 a.m. early in the month, and two hours earlier by month's end.
If you can observe through binoculars or a small scope, pay particular attention to Jupiter's Galilean moons on the night of Sept. 2. A rather rare event is in store. For a little less than two hours, beginning about 10:43 p.m., Jupiter will appear moonless. None of the moons will be visible from Earth.
If you find a dark-sky site and know just where to look, you might be able to see Uranus in the constellation Pisces without optical aid. Shining at magnitude 5.7, it'll look like a faint star, but viewed through a scope, the seventh planet from the sun will reveal its tiny green disk.
Early morning observers will be able to see Venus, Mars and, perhaps, Mercury in the predawn sky.
Venus, the brilliant "morning star," rises around 4 a.m. early in the month and about an hour later by month's end.
Late in September, elusive Mercury can be seen low in the east below Venus about half an hour before sunrise.
Mars is moving in the general direction of the Gemini twins, Castor and Pollux, and is about the same magnitude as the stars, though it has a slight reddish tint. Look for the moon to be nearby on the morning of Sept. 13.
The full moon closest to the autumnal equinox is called the "Harvest Moon." This usually occurs in September, but October gets the honor this year.
If you get a chance to watch an episode of the original "Star Trek" TV classic, do so on Sept. 8. The series premiered on that date in 1966.
Lewis McCool gazes at stars through a 10-inch Dobsonian from his Dolores home.