Geminid Meteor Shower

The Geminid meteor shower is a favorite among northern hemisphere observers and is well known for being the best meteor shower of the year.  Geminids occur every year from about November 19 to December 24.  This year they peak, when the most meteors can be seen, from Friday night, December 13, into the early morning of Saturday, December 14. Typically, meteor showers occur when Earth passes through the debris field left behind by a comet.  The Geminids are unique in that they are the only meteor shower that originates from an asteroid, named 3200 Phaethon.  However, it appears this asteroid was once a comet and is now considered an example of either a dormant or extinct comet. 

Meteor showers get their names from the constellation they appear to radiate from.  The radiant point for the Geminids is the constellation of Gemini, the Twins, near the bright star Castor.  On December 13 Castor will be above the horizon by 8:00PM.  The peak will occur around 2:00AM Saturday morning when Gemini is at its highest point in the sky.  However, during these peak hours the light from a bright waxing gibbous Moon will make seeing all but the very brightest meteors impossible.  Fortunately, the Geminids are known for bright meteors.  Geminids tend to be white, bright, and fast.  You might even see an earth-grazer, a meteor that skims the top of Earth’s atmosphere like a stone skipping across the surface of a pond.  Earth-grazers are more likely to be seen in the evening when the shower’s radiant point is low on the eastern horizon. 

You don’t need any special equipment to see meteors – just your eyes.  The Moon will be up but the best way to observe the Geminids is to find a dark location, if not for the Moon, with open sky.  Stand, sit or lay with your back or the top of your head toward the east, the direction of Gemini at 8:00PM.  This allows you to observe as much sky as possible directly above and around you.  Also, let your eyes become adjusted to the dark – it takes about 20-30 minutes – you’ll see more meteors if you do.   The longer you’re outside and the higher the radiant point is in the sky, the more meteors you will see.  Know that Geminids often come in spurts, interspersed with lulls.  So, grab your lawn chair, warm coat, blanket, and hot beverage of your choice and enjoy the Geminids!