Friday, December 3
Saturday, December 4
Sunday, December 5
Monday, December 6
Tuesday, December 7
The mismatch is due to the steady shift at this time of year in the equation of time, caused by the tilt of Earth's axis and (to a lesser extent) the slight ellipticity of Earth's orbit. The effect is revealed graphically on our Skygazer's Almanac that comes with every January's Sky & Telescope. On it, the sunrise and sunset times on every day of the year are symmetrical around the wavy equation-of-time line down its middle, not the straight midnight line.
Wednesday, December 8
Thursday, December 9
Friday, December 10
Saturday, December 11
Sky at a Glance is now an iPhone app! Put S&T SkyWeek on your iPhone, iPad, or iPod Touch and get the above listings anytime, anywhere — with interactive daily sky maps! Tap a button to see the scene described, customized for your location worldwide. From there you can scroll the view all around the sky, zoom in or out, change to any time or date, and turn on animation. Go to Apple's iTunes store from your device and buy S&T SkyWeek — just 99 cents!
Want to become a better amateur astronomer? Learn your way around the constellations. They're the key to locating everything fainter and deeper to hunt with binoculars or a telescope.
For an easy-to-use constellation guide covering the whole evening sky, use the big monthly map in the center of each issue of Sky & Telescope, the essential magazine of astronomy. Or download our free Getting Started in Astronomy booklet (which only has bimonthly maps).
Once you get a telescope, to put it to good use you must have a detailed, large-scale sky atlas (set of charts). The standards are the Pocket Sky Atlas, which shows stars to magnitude 7.6; the larger Sky Atlas 2000.0 (stars to magnitude 8.5); and the even larger and deeper Uranometria 2000.0 (stars to magnitude 9.75). And read how to use your charts effectively.
You'll also want a good deep-sky guidebook, such as Sky Atlas 2000.0 Companion by Strong and Sinnott, or the more detailed and descriptive Night Sky Observer's Guide by Kepple and Sanner, or the classic if dated Burnham's Celestial Handbook.
Can a computerized telescope take their place? I don't think so — not for beginners, anyway, and especially not on mounts that are less than top-quality mechanically. As Terence Dickinson and Alan Dyer say in their Backyard Astronomer's Guide, "A full appreciation of the universe cannot come without developing the skills to find things in the sky and understanding how the sky works. This knowledge comes only by spending time under the stars with star maps in hand."
This Week's Planet Roundup
Mercury remains in view low about the southwest horizon during evening twilight. Look about 40 minutes after sunset. Mercury fades from magnitude –0.4 to +0.1 this week.
Venus blazes in the southeast before and during dawn. It's still at its maximum brightness (magnitude –4.8 or –4.9) and nearly at its maximum height. If fact it's now rising a good two hours before the first glimmer of dawn (for skywatchers at mid-northern latitudes) — a weird UFO of a thing. Look for much fainter Spica to Venus's upper right, and for Saturn a roughly similar distance above Spica.
Can you follow Venus past sunrise with your unaided eyesight?
Mars (magnitude +1.3) is basically lost in bright evening twilight. But you can use binoculars to try looking for it to the lower right of brighter Mercury, which is closing in on Mars day by day.
Jupiter (magnitude –2.5, at the Pisces-Aquarius border) shines in the south to southwest during evening, the brightest starlike point in the sky. In a telescope it's still 42 arcseconds wide. Jupiter's missing South Equatorial Belt is finally re-forming, as dark markings spread east and west around the planet from bright storm spots that broke out in the SEB's latitude a month ago. The original outbreak site transits Jupiter's central meridian about 3 hours and 40 minutes after the Great Red Spot.
As for the Great Red Spot, it's near System II longitude 157°. Assuming it stays there, here's a list to print out of all the Great Red Spot's predicted transit times for the rest of this observing season.
Saturn (magnitude +0.9, in Virgo) rises around 2 a.m. and glows in the southeast before and during dawn, about 20° upper right of brilliant Venus. The best time to observe Saturn with a telescope is during early dawn, when the planet will be the least blurred by low-altitude atmospheric turbulence. Saturn's rings have widened to 9° or 10° from edge-on.
Uranus (magnitude 5.8) is 2½° east of Jupiter.
Neptune (magnitude 7.9, in Capricornus) is still in the south-southwest right after dark. See our finder charts for Uranus and Neptune online or, with article, in the September Sky & Telescope, page 56.
All descriptions that relate to your horizon — including the words up, down, right, and left — are written for the world's mid-northern latitudes. Descriptions that also depend on longitude (mainly Moon positions) are for North America. Eastern Daylight Time (EDT) equals Universal Time (also known as UT, UTC, or GMT) minus 4 hours.
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