Natural Calendar November 2007

Natural Calendar - November 2007

The purpose of this feature is to give scout leaders, educators and naturalists an idea of some of the natural events coming up each month. We will try to cover a variety of natural events ranging from sky events to calling periods of amphibians, bird and mammal watching tips, prominent wildflowers and anything else that comes to mind. We will also note prominent constellations appearing over the eastern horizon at mid-evening each month for our area for those who would like to learn the constellations. If you have suggestions for other types of natural information you would like to see added to this calendar, let us know!

Note: You can click on the hyperlinks to learn more about some of the featured items. To return to the Calendar, hit the "back" button on your browser, NOT the "back" button on the web page. All charts are available in a "printer friendly" mode, with black stars on a white background. Left clicking on each chart will take you to a printable black and white image.

Notes and Images From October 2007

Facing Northeast,7:00pm CDT, October 29th. Cassiopeia is at the Top, Capella is Rising, Comet Holmes is Arrowed. Nikon D-70, 30 seconds on Fixed Tripod

Comet Holmes, October 31st. Average of Nine 30-Second Exposures made with a 4.5 inch Reflector, Nikon D-70

A Halloween Comet: Our late-October skies were haunted by a rather strange-looking Halloween goblin. On Wednesday, October 24th, Comet Holmes brightened by a factor of approximately one million. Very small and very bright, it looks like a bright fuzzy star to the naked eye. To find it, look to the northeast in the early evening. It can be seen quite easily in Perseus just below the brightest stars of the constellation.

The comet is arrowed in the image at right, taken October 29th. You can use the broken "W" shape of Cassiopeia, at the top of the image, to guide you to the comet. In binoculars, it is an obvious glowing sphere, with no tail. In any small telescope, you can see the small bright star-like nucleus of the comet, and some bright and dark areas within the spherical inner halo. In dark skies, a fainter outer halo can be made out as well. All of the details visible in the image below, taken Halloween night, can be seen fairly easily.

Since the comet and the sun are in almost opposite directions as seen from the earth, the solar wind is blowing the tail of the comet directly away from us, making it difficult to see. Long-exposure images of the comet show faint wisps of the tail showing around the edges of the the bright head. The brighter inner sphere of the comet is composed of dust that reflects the sun's rays. The faint greenish outer halo is composed of gas that is fluorescing. The comet should drift slowly across the constellation of Perseus this month. No one really knows how long it well remain this bright. For more on the comet, go to www.skyandtelescope.com.

Sky Events for November 2007:

The Leonid Meteor Shower peaks in the morning hours of November 18th, with typical hourly rates of 20-40 meteors per hour in dark skies. The moon will not interfere with the shower this year, so conditions will be quite good.

Evening Sky: Look for bright Jupiter low in the southwest at dusk, in Ophiuchus. Mars glows like a hot coal as it approaches opposition in December, rising around 7:45pm CST in Gemini at midmonth.

Morning Sky: Venus rises about 2:45am CST at mid-month. It will shine brightly in the morning sky throughout November. Saturn is in Leo this month, and rises shortly after midnight. Mercury puts on a good show in the morning sky in November, reaching greatest elongation from the sun on November 8th. On that date it rises about 1-1/2 hours before the sun, alongside the bright star Spica.

All times noted in the Sky Events are for Franklin, Tennessee and are Central Standard Time. These times should be pretty close anywhere in the mid-state area.

Constellations: The views below show the sky looking east at 9:00pm CST on November 15th. The first view shows the sky with the constellations outlined and names depicted. Star and planet names are in yellow. Constellation names are in green. The second view shows the same scene without labels. Auriga, the Charioteer, with its bright star Capella, and Taurus, the Bull, with its bright star Aldebaran, are well up into the eastern sky. Look for the Pleiades, a beautiful open star cluster, above Aldebaran. Look for the bright stars Castor and Pollux as the constellation Gemini, The Twins, clears the horizon. Saturn is just below the horizon beneath Castor and Pollux, and a line drawn between these two stars will point to Saturn. Due east, mighty Orion clears the horizon with its bright stars Betelgeuse and Rigel. Note the difference in color between the two stars. Betelgeuse is a red giant and looks orange. Rigel is very hot supergiant and looks bluish. Looking at the center of the three "sword" stars with binoculars, you can see M42, the Orion Nebula. Just poking its head above the horizon is Lepus, The Hare

November 15th, 9:00pm, Looking East

On Learning the Constellations: We advise learning a few constellations each month, and then following them through the seasons. Once you associate a particular constellation coming over the eastern horizon at a certain time of year, you may start thinking about it like an old friend, looking forward to its arrival each season. The stars in the evening scene above, for instance, will always be in the same place relative to the horizon at the same time and date each November. Of course, the planets do move slowly through the constellations, but with practice you will learn to identify them from their appearance. In particular, learn the brightest stars for they will guide you to the fainter stars. Once you can locate the more prominent constellations, you can "branch out" to other constellations around them. It may take you a little while to get a sense of scale, to translate what you see on the computer screen or what you see on the page of a book to what you see in the sky. Look for patterns, like the stars that make up Orion.

The earth's rotation causes the constellations to appear to move across the sky just as the sun and the moon appear to do. If you go outside earlier than the time shown on the charts, the constellations will be lower to the eastern horizon. If you observe later, they will have climbed higher.

As each season progresses, the earth's motion around the sun causes the constellations to appear a little farther towards the west each night for any given time of night. If you want to see where the constellations in the above figures will be on December 15th at 9:00pm CST, you can stay up till 11:00pm CST on November 15th and get a preview. The westward motion of the constellations is equivalent to two hours per month.

A good book to learn the constellations is H. A. Rey's classic, The Stars, A New Way to See Them. Rey's depictions of the constellations and witty commentary are terrific.

A good general reference book on astronomy is the Peterson Field Guide, A Field Guide to the Stars and Planets, by Pasachoff.

My favorite books about astronomers are Richard Preston's First Light, and the wonderful Starlight Nights, by Leslie Peltier.

A good beginners software program for learning the night sky is the Starry Night Beginner program. Visit the Starry Night web site at www.starrynight.com The program retails for around $30.00 and contains a wealth of information.

The best compact star atlas that I know of for use at the telescope is Sky & Telescope's Pocket Sky Atlas, published by Sky Publishing Corporation. This beautifully crafted star atlas is a joy to look at and a joy to use.

Amphibians:

Male Green Frog

We think of November as the quietest time of year for Tennessee frogs and toads. However, some song can still occasionally be heard. Listen for Spring Peepers, Southeastern Chorus Frogs and Southern Leopard Frogs. Checking around ponds at night with a flashlight held next to your temple will many times show the eye shine of Southern Leopard Frogs, Green Frogs and Bullfrogs. As in October, you can locate many of the frogs and toads that have been calling more frequently earlier in the year by driving the back roads slowly on rainy nights. This is a two person job. One person watches the road for amphibians and one person looks out for other vehicles.

Birds:

You probably have already put out your bird feeders, but if you haven't you'll be missing out on a lot of good looks at winter feeder birds. This is a great time of year to start learning bird identification. Watch and listen for fall arrivals like White-throated and White-crowned Sparrows, Yellow-bellied Sapsuckers, Red-breasted Nuthatches and Brown Creepers. Listen for Great Horned Owls dueting at dusk and dawn and sometimes through the night during their courtship period.

Recommended:

Bird Finding in Tennessee, Michael Lee Bierly. A classic guide to finding birds in Tennessee.

The Sibley Guide to Birds, David Allen Sibley

The Sibley Guide to Birds of Eastern North America, David Allen Sibley

A Field Guide to the Birds of Eastern and Central North America, 5th edition. 2002. Roger Tory Peterson and Virginia Marie Peterson. If it's been a while since you've picked up a Peterson bird guide, you may be pleasantly surprised by the large image scale of the drawings. Just the thing for those fall warblers!

An inexpensive guide for beginners is the Golden Guide for Birds.