Last modified: Wednesday, November 28, 2007
Geminid meteors adorn December sky
FOR IMMEDIATE RELEASE
Nov. 29, 2007
BLOOMINGTON, Ind. -- The annual Geminid meteor shower will peak on the night of Dec. 13-14. The Geminids usually offer the best show of the year, outperforming even the better-known Perseid meteor shower of August. But watching the Perseids is a pleasant way to spend a warm summer evening, while waiting outdoors on a winter night for Geminids is a bit like sitting in a refrigerator and trying to think about global warming. It can be hard to concentrate.
This year's Geminid shower will peak a few days after new moon, so skywatchers can expect to see 60-70 meteors per hour in a dark sky. City lights will wash out all but the brightest meteors, so try to get away from them if you can. Some meteors will appear as soon as the sky is completely dark, and the numbers will increase as the evening advances. The nights before and after the peak should also provide good opportunities for meteor watching.
The meteors or "shooting stars" will seem to be coming from a point called the radiant near the bright stars Castor and Pollux in the constellation Gemini the Twins, which gives the shower its name. The radiant will be well above the eastern horizon a few hours after sundown and will remain high in the sky for the rest of the night. The higher the radiant is above the horizon, the more meteors there will be. Try facing southeast if you have a clear view in that direction, though meteors will be visible in all parts of the sky. For details about the Geminid shower, see http://www.amsmeteors.org/showers.html#geminids.
To stay comfortable in the frigid night, wear several layers of your warmest clothing and keep a thermos of hot coffee, tea or chocolate handy. A sleeping bag or blankets also will help. If necessary, go indoors from time to time to warm up. No special equipment is needed to watch a meteor shower. A reclining lawn chair will work fine. Try facing in different directions and see how the meteors vary in appearance. The ones closer to the radiant will be short, since they will appear to be coming toward you. Those farther from the radiant will be longer and probably fewer.
Mars will dominate the night sky for the next few months, but especially during December as it soars high overhead for observers at mid-northern latitudes. This will be as far north as Mars ever gets. Well above the eastern horizon by 9 p.m. local time, the bright orange planet will glow even more as the month passes. It will reach opposition -- opposite the sun in our sky -- on Dec. 24, when it will be visible all night at its brightest, rising in the east at sunset and setting in the west at dawn. The full moon will be near Mars on Dec. 23, the night before opposition. In some parts of Europe and the Pacific Northwest, the moon will actually cover the planet that night.
Mars won't appear this big or bright again until 2016. It will be dazzling even without optical aid, but this is the time to turn a telescope on Mars if you have one. Turbulence in Earth's atmosphere is a constant hindrance even when Mars is so high in the sky, but patience will reward you with moments of steady viewing. Information on observing and imaging Mars can be found at http://elvis.rowan.edu/marswatch/images.php and http://www.lpl.arizona.edu/~rhill/alpo/mars.html.
Saturn will trail the bright star Regulus up into the eastern sky around midnight at the beginning of December, and two hours earlier by month's end. Seen through a telescope, Saturn's famous rings are now tilted closer to edgewise than they have been in a decade. Titan, Saturn's brightest moon, will be north of the planet on Dec. 4-5 and 20-21, and south of the planet on Dec. 12-13 and 28-29.
The brilliant white object in the east in the morning sky will be Venus, rising about three hours before the sun during December. It will remain high at dawn throughout the month for observers at mid-northern latitudes.
Jupiter will disappear into the sun's afterglow during December, and Mercury will be out of sight behind the sun all month.
The sun will be farthest south in Earth's sky on Dec. 22 at 1:08 a.m. Eastern Standard Time (6:08 Universal Time), marking the beginning of winter in the Northern Hemisphere and summer in the Southern Hemisphere. For the next six months in the Northern Hemisphere the days will be getting longer.
The moon will be at third quarter on Dec. 1, new on Dec. 9, at first quarter on Dec. 17, full on Dec. 23 and at third quarter again on Dec. 31.