A few hours after sunset local time, on Wednesday December 13th, look toward the west for ‘shooting stars’, or meteors coming from the area around the constellation the Gemini Twins. These are the annual Geminid Meteor Shower – one of the best meteor showers each year, and at times rivaling the August Perseid Meteor Shower. The calculated peak time for the meteors is December 14th at 7 UT (2 am CST), but this does not mean that is the only time to view them. The Geminid Meteor Shower is named for the constellation that the meteors radiate outward from. This is the same for all meteor showers, and the ‘spot’ in the sky is known as the radiant. The Geminid radiant is just above the ‘twin’ star Castor, and under ideal viewing conditions an average of about 70 meteors per hour could possibly be seen. This year without the interference of moonlight will increase the chances of seeing the meteors.
Meteor showers result from the Earth’s orbital path intersecting areas of comet debris. Comets, as they orbit the Sun, leave behind pieces of their icy, dirty, selves. If these debris clouds happen to be along the Earth’s orbital path then the Earth will regularly pass through the comet debris cloud. As this happens the small comet pieces hit our outer atmosphere and vaporize from the friction generated heat. We then see these as the shooting stars that make up meteor showers.
There are, however, two exceptions to this. The January Quadrantid Meteors and the Geminids each come from their own respective asteroid rather than a comet. The source for the Geminids is Asteroid 3200 Phaethon
Click here to go to the Qué tal in the Current Skies web site for more observing information for this month