Minnesota Star Watch: Moon puts on a show
By Deane Morrison, University of Minnesota
The moon puts on two spectacular shows this month: a total lunar eclipse and a partial solar eclipse.
The lunar eclipse happens in the wee hours of the 8th, as the full hunter’s moon glides through the northern part of Earth’s shadow. The Earth’s inner shadow—the umbra—swallows the moon between 4:15 a.m. and 5:25 a.m. The moon begins its exit of the umbra at 6:24 a.m., and slips completely free at 7:34 a.m.
The eclipse of the sun on the 23rd happens in late afternoon and ends with the sun setting while still in partial eclipse. For the Twin Cities area, the moon takes its first bite out of the sun at 4:23 p.m., and maximum eclipse is at 5:35 p.m., when almost 52 percent of the sun’s face will be covered.
When watching any solar eclipse, do not observe it directly; use a pinhole camera. For lunar eclipses, no special precautions are necessary.
In the southwestern evening sky, watch the distance between Mars and Antares, its stellar rival, widen. Both objects are low, with Mars the higher and more eastern of the two. Better hurry, though; Antares is sinking fast and will be hard to find by mid-month. But Mars manages to stay up, while behind it the summer stars slide past. On Halloween, the Teapot of Sagittarius and the Red Planet come face to face.
In the predawn sky, Jupiter is climbing in the southeast, followed by the bright star Regulus, in Leo. See if you can make out the Sickle of stars outlining the lion’s head—Regulus is at its base. For maximum effect, try on the 18th or 19th; a waning crescent moon appears near the pair on both mornings.
Look for the Orionid meteors streaming from the south, near the raised club of Orion, after midnight on the 21st and 22nd. With a comfortable reclining chair and a moderate amount of patience, you could enjoy up to 20 meteors an hour. These meteors come from dust left by Halley’s Comet.
If October lives up to its reputation as a month of clear, crisp air, this is a good time to grab a star chart and find the fall constellations. In the far south, the bright star Fomalhaut ornaments Piscis Austrinus, the southern fish. Higher and slightly west, chevron-shaped Capricornus, the sea goat, features no particularly bright stars. Moving northeast, look for the spidery form of Aquarius, the cupbearer to the gods; his name, Ganymede, is now borne by one of Jupiter’s moons. Next comes the Circlet of Pisces, and above it the Great Square of Pegasus, which dominates the sky.
October ends with an astronomy-based holiday. Halloween began as the Celtic holiday of Samhain (rhymes with HOW-when). It marked the start of the dark half of the year, which ended on May Day—or, as it is still sometimes called, Beltane. On Samhain, the evil spirits that had been cooped up for six months broke loose and lived it up—i.e., they wreaked havoc. So people tried to appease them with offerings of food and used gourd lanterns to ward them away. These traditions survive as trick-or-treating and jack o’ lanterns. This year, a just-past-first-quarter moon will light the way for the latest crop of little ghosts and goblins.
The University of Minnesota offers public viewings of the night sky at its Duluth and Twin Cities campuses. For more information and viewing schedules, see:
•Duluth, Marshall W. Alworth Planetarium: www.d.umn.edu/planet
•Twin Cities, Minnesota Institute for Astrophysics (during fall and spring semesters): www.astro.umn.edu/outreach/pubnight.
•Check out the astronomy programs at the University of Minnesota’s Bell Museum ExploraDome: www.bellmuseum.umn.edu/ForGroups/ExploraDome/index.htm.
Find U of M astronomers and links to the world of astronomy athttp://www.astro.umn.edu.