The Night Sky of November

Dr. Wayne Wooten
Professor of Astronomy

(2010) For November, the Moon will be new on November 6th, so the first week of November will thus find the Moon a waning crescent in the dawn skies. The crescent moon lies 7 degrees south of Saturn on the morning of November 4th, and very close to Venus, now also a thin crescent in the morning sky, on November 5th, but they are only 12 degrees west of the rising Sun, and so hard to spot. The waxing crescent moon passes south of both mercury and Mars in evening twilight on November 7th (don’t forget to change the clocks back to standard time that Sunday, by the way!) but again, all lie close to the sun, just setting 30 minutes before.

The moon is first quarter moon on November 13th, and the waxing gibbous moon passes six degrees north of Jupiter in the SE evening sky on November 16th. As it sets before midnight, the peak for the Leonid Meteor Shower in the dawn hours of November 17th may give us several meteors per hour, coming swiftly out of the east. The full moon for November is the Frosty Moon, and falls on November 21st, and the last quarter moon on November 29th.

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 2010; 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 2010 sky, featuring many different objects, available from the Hubble Space Telescope website.

Except for Jupiter, the other naked eye planets all lie close to the Sun this month and are hard to observe. Giant Jupiter dominates the SW sky in Pisces at the beginning of November. Any small scope will reveal what Galileo marveled at four hundred years ago; 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. Larger scopes will still show detail on the disk, but observe early in the evening to catch the famed Great Red Spot the South Equatorial belt that normally sit atop the GRS faded away last April for reasons not understood, but may be redeveloping currently.

Setting in the southwest 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. Use binocs and your sky map to spot many clusters.

Overhead the square of Pegasus is a beacon of fall. South of it lies Jupiter currently, but still farther south 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, using your sky map. Our photo this month reminds us why this stellar striptease has sometimes been called 'the eye of God' by the press. When our own Sun swells to a red giant perhaps six billion years from now, it too will probably shed its outer layers as such a nebula, before its core collapses to an earth sized white dwarf, like the faint central star shown in Bob’s photo.

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. It appears as an oval blur with the naked eyes alone.

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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