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The Sky of November

Dr. Wayne Wooten
Professor of Astronomy
Escambia Amateur Astronomers' Association

For November, the Moon will be new on October 29th, so the first two weeks of November will thus find the Moon waxing and visible in the evening sky. The waxing crescent moon is passing about 3 degrees south of Venus on November 1st. The crescent moon appears two degrees south of Jupiter on November 3rd. First quarter moon sits high in the sky and half-lit at sunset on November 6th. The full moon is the Frost Moon (at least in the days before Global Warming!), and occurs on November 13th. The last two week of November finds the moon waning in the morning sky, passing by almost ringless Saturn on November 21st. Last quarter moon is November 19th, and the new moon is on November 27th.

While the naked eye, dark adapted by several minutes away from any bright lights, is a wonderful instrument to stare up into deep space, far beyond our own Milky Way, binoculars are better for spotting specific deep sky objects. For a detailed map of northern hemisphere skies, about Halloween visit the www.skymaps.com website and download the map for November 2008; it will have a more extensive calendar, and list of best objects for the naked eyes, binoculars, and scopes on the back of the map. Also available as the next month begins is wonderful video exploring the November 2008 sky, featuring many different objects, available from the Hubble Space Telescope website at: http://hubblesite.org/explore_astronomy/tonights_sky.

Venus dominates evening, setting almost two hours after the Sun as November begins, and three hours later by the end of the month. She appears 80% sunlit on November 1st, but only 70% at month’s end. As our sister overtakes us, she appears to get a little larger (from 14' to 16' of arc) She is now on the far side of her orbit, and will pass between us and the Sun in early 2009. It was Galileo in 1611 who noted that Venus goes through this entire phase cycle, and correctly deduced this proved she orbited the Sun, not us. Covered with sulfuric acid clouds, her bright disk reveals no visible details in the scopes.

Giant Jupiter dominates the SW sky at the beginning of November, but will be lost in the Sun’s glare by Christmas. Any small scope will reveal what Galileo marveled at in 1609; four large moons, all bigger or similar to ours in size, orbit it in a line along Jupiter’s equator. So get out the old scope, and focus on Jupiter for a constantly changing dance of the moons around the giant world.

East of Jupiter is the teapot shape of Sagittarius, which marks the heart of our Milky Way Galaxy, but the best view of our Galaxy lies overhead now. The brightest star of the northern hemisphere, Vega dominates the sky in the northwest. To the northeast of Vega is Deneb, the brightest star of Cygnus the Swan. To the south is Altair, the brightest star of Aquila the Eagle, the third member of the three bright stars that make the Summer Triangle so obvious in the NE these clear autumn evenings.

Overhead the square of Pegasus is a beacon of fall. South of it lies the only bright star of Fall, Fomalhaut. If the southern skies of Fall look sparse, it is because we are looking away from our Galaxy into the depths of intergalactic space. It is just north of Fomalhaut that you will find the closest and largest of the planetary nebulae, NGC 7293 or ‘the Helix’, about 650 light years distant. It appears as a faint ring, half as big as the full moon, and visible with binocs from a dark, clear observing site.

The constellation Cassiopeia makes a striking W, rising in the NE as the Big Dipper sets in the NW. Polaris lies about midway between them. She contains many nice star clusters for binocular users in her outer arm of our Milky Way, extending to the NE now. Her daughter, Andromeda, starts with the NE corner star of Pegasus’‘ Square, and goes NE with two more bright stars in a row. It is from the middle star, beta Andromeda, that we proceed about a quarter the way to the top star in the W of Cassiopeia, and look for a faint blur with the naked eye. M-31, the Andromeda Galaxy, is the most distant object visible with the naked eye, lying about 2.5 million light years distant. Bob Gaskin’s new photo of it shows the dust lanes in the spiral arms well; these are places where new stars and planets are being formed as we watch.

To the northeast, Andromeda’s hero, Perseus, rises. Between him and Cassiopeia is the fine Double Cluster, faintly visible with the naked eye and two fine binocular objects in the same field. Perseus contains the famed eclipsing binary star Algol, where the Arabs imagined the eye of the gorgon Medusa would lie. It fades to a third its normal brightness for six out of every 70 hours, as a larger but cooler orange giant covers about 80% of the smaller but hotter and thus brighter companion as seen from Earth. Check it out on a clear November evening, and see it the gorgon is winking at you. If so, then instead of being as bright as Polaris, Algol fade to be only as bright as kappa Persei, the star just to its south. Look at Perseus’ feet for the famed Pleiades cluster to rise, a sure sign of bright winter stars to come. In fact, yellow Capella, a giant star the same temperature and color as our much smaller Sun, rises at 7 PM as November begins.

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