Geminids Meteor Shower: 'Up All Night' With NASA!
Put on the hot chocolate...find a warm, toasty location...and join us on the night of Dec. 13-14 for our "Up All Night with NASA" live Web chat about the 2011 Geminid meteor shower!
The Geminids -- the final major meteor shower of the year -- will be somewhat obstructed by a waning gibbous moon
. Anytime between Dec. 12-16 is a valid window for Geminid-watching, but the night of Dec. 13-14 is the anticipated peak.
On Tuesday, Dec. 13, meteor experts Dr. Bill Cooke, Danielle Moser and Rhiannon Blaauw from NASA's Marshall Space Flight Center answered your questions about the Geminids via a live Web chat.
› Chat Transcript (PDF, 528 Kb)
More About the Geminids
Geminids are pieces of debris from an object called 3200 Phaethon, which is something of a mystery. Near closest approach to the Sun (perihelion), Phaethon exhibits increases in brightness similar to that of a comet; however, its orbit is characteristic of an asteroid. Extinct comet or asteroid? The debate still rages among astronomers.
In mid-December of each year, Earth runs into the stream of debris from Phaethon, which causes the Geminid meteor shower -- a beautiful display of meteors for us to enjoy. Unlike the Perseids or Leonids, the Geminids are a relatively young meteor shower, with the first reports occuring in the 1830's citing rates of about 20 per hour. Over the decades the rates have increased -- it is now the best annual meteor shower - and we regularly see between 80 and 120 per hour at its peak on a clear evening. The Moon will hamper that this year, but if your skies are clear you can still expect to see as many as 40 per hour.
One can tell if a meteor belongs to a particular shower by tracing back its path to see if it originates near a specific point in the sky, called the radiant. The constellation in which the radiant is located gives the shower its name; Geminids all appear to come from a point in Gemini, Leonids appear to radiant from Leo, and so on.
More About the Chat Experts
Janet Anderson, 256-544-0034
Marshall Space Flight Center, Huntsville, Ala.