Geminids Meteor Shower 2015

The Geminids meteor shower 2015 will begin on December 4th next and will continue until December 17th. The annual Geminids meteor shower will peak on the nights of the 13th and 14th of December. The Geminids are one of the more spectculr meteor showers of the year, where it is possible to see up to 120 meteors an hour. With the Moon just 3 days past new and setting at the end of evening twilight, conditions couldn’t be more ideal. Of course providing the weather is favourable with clear skies!

geminids meteor shower

Photo: Stardate.Org

The best chance to view the Geminids meteors is to get out to the countryside, away from all light pollution from street lights. Of course you will also need a cloudless sky! Thankfully the moon will be waxing crescent and the night sky will be darker. The best time to view the meteors is from 10pm to dawn. Be aware that meteors often come in spurts, interspersed by lulls.

Geminids meteor shower for Dublin (Night between 13 Dec and 14 Dec)
Time Azimuth/Direction Altitude
Sun 17:00 32°North-northeast 2.0°
Sun 18:00 44°Northeast 7.4°
Sun 19:00 55°Northeast 14.1°
Sun 20:00 65°East-northeast 21.8°
Sun 21:00 76°East-northeast 30.3°
Sun 22:00 87°East 39.1°
Sun 23:00 100°East 48.1°
Mon 00:00 115°East-southeast 56.6°
Mon 01:00 137°Southeast 63.9°
Mon 02:00 167°South-southeast 68.3°
Mon 03:00 201°South-southwest 67.7°
Mon 04:00 229°Southwest 62.5°
Mon 05:00 249°West-southwest 54.8°
Mon 06:00 263°West 46.1°
Mon 07:00 276°West 37.1°

Because all meteor showers arrive on parallel paths traveling at the same speed, they appear to radiate from a single point in the sky. The radiant is nothing more than a perspective effect, the very same as railroad tracks appearing to converge in the distance. Meteors near the radiant leave very short trails; the farther away you look, the longer the trail. It’s not necessary to directly face the radiant because shower meteors appear all over the sky.

What causes the Geminids meteor shower?
Geminids meteor shower

Animation: Nasa

Unlike most other meteor showers, the Geminids are associated not with a comet but with an asteroid – the 3200 Phaethon. The asteroid takes about 1.4 years to orbit around the Sun. Every year, in December, our planet Earth crosses the orbital path of asteroid 3200 Phaethon, a mysterious body that is sometimes referred to as a rock comet.

In periods of 1.43 years, this small 5-kilometer (3-mile) wide asteroid-type object swings extremely close to the sun (to within one-third of Mercury’s distance), at which juncture intense thermal fracturing causes this rocky body to crack and crumble, and to shed rubble into its orbital stream. Annually, at this time of year, the debris from 3200 Phaethon crashes into Earth’s upper atmosphere at some 130,000 kilometers (80,000 miles) per hour, to vaporize as colourful Geminid meteors.

Photographing the Geminids meteor shower

As with all night time and Astro photography a tripod is a must. A wide angle lens would be preferable, 10mm to 20mm if you have one. If not use the widest lens you have, to capture the most of the night sky. You might need to try different camera settings, maybe start off at a wide aperture f/2.8 or f/3.5. Set your ISO to 800 or 1000 and try differfent exposure times, 5, 10 15 seconds. Its all a matter of trial and error!

 

For more information visit timeanddate.com & Earthsky.org.