The 2012 Geminid Meteor Shower promises to be the most spectacular of all this year’s major annual displays of “shooting stars.” Be sure to mark Thursday evening into early Friday morning, December 13th to 14th, on your calendar and plan to head outdoors if skies are clear. The total absence of the Moon and an early evening start to the event combine to make ideal conditions for meteor watching this month.
This year’s Perseid Meteor Shower put on a great show back in August, but it was somewhat compromised by bright moonlight during part of the display—and widespread cloudiness across much of the country prevented many of us from seeing it. So this month’s Geminids offer a wonderful “rain check.” It’s one of the most observed annual showers due to a consistent intensity of as many as 100 shooting stars per hour during its peak activity as seen under a dark sky. They appear to radiate from near the bright star Castor, one of the two “Twin Stars” marking Gemini, the mythological twins (the other being the star Pollux). To find them, set your Scientifics Star and Planet Locator for about 7:00 p.m. around mid-December and face northeast, where you’ll see the pair just clearing the horizon. Unlike most other meteor showers whose host constellations typically don’t rise until the hours after midnight, this one is already above the horizon after dark, making this shower ideal for early evening viewing.
The shower will be best seen on the evening of November 13th into the early morning hours of
the 14th, with maximum activity expected sometime after midnight. And this year, the Moon is at its New phase that same night and will offer no interference at all. If you watch thorough the evening hours, you’ll notice that the number of meteors seen increases as the night grows later. This is partly because Gemini continues to rise ever-higher in the sky. But there’s also another more important factor at work here. In the evening, we’re on the side of our planet “facing away” from the direction the meteors are approaching and so they have to “catch up” with us. But after midnight we’re turned into the direction of the radiant, causing them to slam into the atmosphere at much higher speeds and resulting in many more of them being seen. So the later you observe the more activity you can expect to see.
Observing meteors is basically a naked-eye activity in order to survey as large an area of sky as possible. A helpful technique here is to face east toward the radiant while concentrating your attention on the sky overhead—ideally reclining comfortably on a lounge chair as you do. Using your Edmund binoculars is also encouraged for following the smoke trails or “trains” often left behind by many of the brighter meteors. And pointing these glasses at the radiant itself, you may even be fortunate enough to see a meteor coming directly at you—appearing from out of the darkness as a brightening “star” and ending its flight in a blinding burst of light. This is a Geminid meant expressly just for you!
Former assistant editor at Sky & Telescope magazine and author of eight books on stargazing