The year is coming to an end and this is the time when astronomers get a treat in the form of the Geminid Meteor Shower that peaks on 13-14th December.
What is Geminid Meteor Shower?
The Geminid Meteor Shower is an annual meteor shower that peaks in the month of December. Annual meteor showers arise when the Earth passes through streams of debris left behind by comets and asteroids. As pebble-sized pieces of debris collide with the Earth, they burn up at an altitude of around 70 to 100 km, appearing as shooting stars. The parent body responsible for creating the Geminid shower is the comet 3200 Phaethon. Thus together with the Quadrantids, Geminids is the only meteor shower that doesn't originate from an asteroid.
What is so special about Geminids?
Most people relish the Perseid meteor shower that peaks on August 12 every year and that's because the nights are not cold and a fair number of people are on vacations. In contrast, the Geminids peaks in December, in freezing cold weather. However, Geminids promises a better view due to many reasons.
The Geminids typically encounter Earth at around 22 miles (35 kilometers) per second. That's about half the speed of a Leonid meteor. And only about 2 to 4 percent of all Geminids leave a persistent train in their wake. That's probably due to their composition: At 2 grams per cubic centimeter (1.15 oz per cubic inch) on average, Geminid meteoroids (the term for meteors before they hit the atmosphere) are several times denser than the cometary bits of fine dust that make up most meteor showers.
How to watch the shower?
Every meteor shower has an associated radiant with it. The radiant is the point from where all the meteor strikes appear to originate. Meteor paths appear at random locations in the sky, but the apparent paths of two or more meteors from the same shower will converge at the radiant. The radiant is the vanishing point of the meteor paths. The position of the radiant matters a lot when it comes to watching the shower.
The radiant of the Geminids is near the star castor in the constellation of Gemini (hence the name Geminid meteor shower). The peak activity will take place on December 14 at 12:00 GMT. This particularly favours the viewers in North America. However, it won't make much difference and viewers from India, Canada, Europe etc can equally relish the show. In India, Gemini rises at around 8:40 p.m. and by midnight, the radiant (near the star castor) is fairly up in the sky. The position of Gemini is given in the map below. This will be the exact location of Gemini at 10:30 p.m. from New Delhi on December 14.
The best time for Geminid viewing will come at 2 a.m., when the constellation Gemini will stand almost directly overhead. (Note that the times in this paragraph refer to your local time zone, wherever you're watching from.)
The Geminids perform superbly in most years. However, as was the case for last month's Leonids, the moon will pose a small hindrance. It will reach first-quarter phase on Dec. 15, the day after the Geminid peak. On the evening of Thursday, Dec. 13, the moon will shine brightly in the dim constellation of Aquarius, the water carrier. That means that moonlight could wash out some of the fainter Geminids. However, the moon will set by around 10:30 p.m. local time on Thursday, leaving the sky dark and moonless for the balance of the night and making for perfect viewing conditions. In a perfectly dark sky, 120 meteor strikes per hour are expected at the peak time.
A few tips: Look up for as wide a view of the sky as possible. Perhaps listen to some music as you watch. Lastly, give your eyes time to dark-adapt before you look — and good luck!