The glorious Geminids meteor shower lights up local skies December

By Angelika Hackett

One of the best night sky spectacles of the year returns in December!

It’s the annual meteor shower known as the Geminids. If you’ve ever wondered what they are and why they are called that, read on.

As the earth travels around the sun, it regularly passes through clouds of debris, made up of tiny dust particles. This dust is shed and left behind by a comet during its passage around the sun.

When earth meets up with such a dust cloud, these particles (called meteoroids) enter the atmosphere, flashing up as meteors.

Some are bright enough to leave a fiery trail. Larger pieces reaching the ground – a rare event – are called meteorites.

When you drive through a snowstorm, the snow appears to be coming at you from a point. Likewise, as the night-time side of earth is racing through a dust cloud, the meteors appear to come at us from a point – the radiant.

The background constellation of stars behind the radiant gives the shower its name.

In August, the Perseids’ radiant is in the constellation Perseus. The Perseids are caused by debris from Comet 109P/Swift-Tuttle which orbits the sun every 133 years. The December Geminids appear to originate from the constellation Gemini (Latin for “twins”), but can flare up anywhere in the sky.

The twins are the mythological half-brothers Castor and Pollux, one of them the offspring of a philandering Zeus! They are the two bright stars at the eastern end of the constellation Gemini. It’s located just east of Orion, in the south-eastern sky in the evening, moving westward throughout the night.

This shower is unusual – it is not

caused by dust from a comet, but rather from an asteroid, 3200 Phaethon. A comet is basically a dirty snowball in a very large orbit around the sun; an asteroid is a solid body, also revolving around the sun.

Phaethon approaches the sun closer than any other named asteroid, shedding dust and particles due to its relatively high temperatures. Orbiting the sun every 534 days, it is named after the mythological sun-god Helios’s son.

How to watch the Geminid's in qathet

This year’s Geminids’ peak on December 14 at 11 am, when the earth passes through the thickest part of the dust cloud. That’s unfortunately in the daytime, but both nights of December 13 and 14 should be good for observing, especially since the waxing crescent moon will set early. We are lucky in qathet for having several nearby areas with no interfering lights. Now hope for clear skies! The best places in qathet would be any dark area away from lights. People in the countryside or on Texada have an advantage! Mowat Bay is good – we went there for the Perseids in August. The Willingdon pier would be good, too, with a wide open sky, although there are some lights still visible. But you could simply sit in your back yard if it has a view of much of the sky and is dark (ask your neighbours to turn off any bright security lights!) It would be an advantage to have a clear view to the south-east toward Gemini, but the meteors can appear anywhere in the sky.