Now playing overhead: The dramatic Geminid Meteor Shower, which many astronomers agree is the best meteor shower of the year. Following that, stargazers could keep their necks craned for 2010's only complete lunar eclipse, which coincides with Winter Solstice December 21.
The Geminid Meteor Shower is forecast to peak late Mon./early Tues. Dec. 13-14, between around midnight and sunrise, in North America. If you can't stay up that late, not to worry -- astronomers tell us that some meteors should be visible as soon as darkness hits. In addition, the shower lasts for days before and after the peak date, and there have already been reports from around the world of people spotting spectacular fireball-like celestial streaks.
What is a meteor shower?
Meteors occur when the Earth passes through streams of dust and debris from ancient comets which have entered the Earth's atmosphere. (When the comet has flown close to the sun, its dirty ice evaporated and that, in turn, caused the comet dust to spew into space.) Scientists believe that the Geminids actually come from an asteroid, called 3200 Phaethon, which is really the skeleton of an extinct comet. The Earth passes through this particular debris stream each December, and is said to originate near the constellation Gemini.
How to watch the Geminid Meteor Shower
Good news! The Geminids should be visible with the naked eye in North America and perhaps in other parts of the world. Sky watchers in cold climates should bundle up, grab a chair (ideally one with some neck support), and perhaps a blanket, head outside where you can see the largest patch of night sky possible (with as little city light as possible), and look up.
Because meteor showers last for days before and after the projected peak, be sure to scan the skies during the surrounding days, if you can. This time of year, clouds can obscure the Geminids on the peak day, as can the moon, which will be in its first quarter.
A thermos of hot chocolate is a great accompaniment for the Geminids.
This shower has been getting stronger every year it's been recorded, going back the the 1860s. It could be "an amazing annual display", according to Bill Cooke of NASA's Meteoroid Environment Office.
This American Meteor Society page is a great site for exploring more about the Geminids and where and when to see them in your local night sky.
This movie of the 2008 Geminids comes from a space camera at the Marshall Space Flight Center.
After the Geminids, night-sky gazers can look forward to a full lunar eclipse that will coincide with the winter solstice Dec. 21.
What is a Lunar Eclipse?
A lunar eclipse occurs when the moon passes through a point in its orbit when the Earth is directly between it and the sun, and the moon is in the shadow of the Earth.
In the Western Hemisphere, the eclipse will "officially" begin on Dec. 21 at 12:29 a.m. EST (9:29 p.m. PST on Dec. 20). As with the Geminids, the best way to see the eclipse is to hope for clear weather, go outside, and look up. It takes about 45 minutes to notice any changes in the moon's appearance as the shadow moves slowly across it. The lunar eclipse should be visible in North and South America, the northern and western part of Europe, and a small part of northeast Asia. A complete lunar eclipse won't happen again in North America until 2014.