Every December, the Geminid Meteor Shower shows itself to be one of the most reliable meteor showers of the year — and this year is especially worth braving the cold.
The prolific shower peaks at about 120 meteors per hour, or approximately two per minute. This year, the Geminids are expected to peak overnight December 13-14 at new Moon, meaning your observing can be done under a dark sky.
While most meteor showers are from comet debris, the source of the Geminid Meteor Shower is the asteroid 3200 Phaethon. At roughly five kilometres across, 3200 Phaethon has a 1.4-year elliptical orbit that takes it through the inner Solar System. NASA states astronomers are still trying to figure out why this space rock is shedding so much, noting that it could be a “dead comet” or a new kind of object called a “rock comet,” an asteroid that comes so close to the Sun that dusty debris is scorched off its rocky surface.
Meteor showers require no special equipment; all you need is your eyes. Make sure to dress warmly before going outside. Move as far away from artificial light sources as you can, and give your eyes about 20 minutes to adjust to the darkness. If you must consult a star chart, use a red light or red filters over your flashlight or mobile phone.
The radiant of the shower appears in the constellation Gemini, although the brightest and longest-lasting meteors will be somewhat away from Gemini (away from the direction where the Earth directly hits the stream of dust).
To find Gemini, look for the north star (Polaris) in the sky and then turn to the opposite direction. In the winter sky, the southern view should show you Orion the Hunter, anchored by the red star Betelgeuse (on the right shoulder, left from our perspective) and the blue star Rigel (on the left leg, right from our perspective.)
Look up and to the left of Betelgeuse and the next brightest stars you see is the pairing of Pollux and Castor, at the head of the Gemini constellation (the Twins).
You won’t need binoculars or a telescope. Instead, aim your camera at one direction of the sky, take several long exposures, and hope that meteors will be captured.
In general, set your lens focus to infinity and open it to the widest aperture that you can. (You can focus on a bright star or planet to sharpen the image). For best results, steady your camera on a tripod or solid object, use IS0 1600 and point your camera straight to the zenith of the sky, where there is the least atmospheric interference. Try exposures ranging from between 10 and 30 seconds each. It may take you several tries (or a few nights) to get something on camera, but the payback is worth it.
Elizabeth Howell (Ph.D.) is a Canadian space journalist who has been obsessed with the topic ever since she, as a young teenager, saw the movie Apollo 13 in 1996. She grew up wanting to be an astronaut. While that hasn’t happened (yet), Elizabeth has seen five human spaceflight launches — including two from Kazakhstan — and she participated in a simulated Red Planet mission at the Mars Society’s Mars Desert Research Station in Utah.