Earth will be treated to "arguably the best meteor shower of the year" on the weekend when it passes through the Geminids, an astronomy writer says.
The Geminids, which got their name because the meteors originate from a point in the sky near the constellation Gemini, reach their peak activity on the nights of Dec. 13 and 14.
Gary Seronik, an experienced observer who writes for SkyNews, said most meteor showers are the result of Earth passing through the trail of debris left by a comet.
"Comets go around the sun just the same way the Earth does, but their orbits are a slightly different shape, and comets are kind of like bad tourists — they leave garbage wherever they go," Seronik told Sheryl MacKay,host of CBC Vancouver's North by Northwest, in an interview to be aired on the weekend on the Radio One network. "So if you happen to drive the Earth through that trail of garbage you get a meteor shower."
Geminid meteors appear to radiate from a point near the bright star Castor, a star in the Gemini constellation. (SkyNews.ca)
However, Seronik says, the Geminids are different,because the trail of debris is from 3200 Phaethon, an unusual object he says is best described as a "rock comet" — a small solar system body that exhibits features of both a comet and an asteroid
"It's sort of like an asteroid, but asteroids typically don't leave behind debris that produce meteor showers, and it's sort of like a comet because its orbit is quite elliptical like a comet is and brings it closer to the sun" he said.
"It's a bit of a mystery object."
How and when to see them
Seronik said the peak of the activity ("when the Earth goes through the densest part of that debris stream") is on the nights of Dec. 13 and 14, but added they can also be seen three or four nights before and after.
He said anytime of night will work to see them, but said later at night you will see more meteors.
"If you can stay up to midnight that's a good time to be looking for Geminids. Go outside, bundle up, bring a thermos of coffee and your lawn chair and face east," he said.
"Meteors are impressive on another level, too, as that bright streak you're seeing in the sky is often times the result of a particle no bigger than, say, a pea or a small pebble," he said.
"But it's a good illustration of that famous equation we all learned in high school, e=mc². A little bit of mass times the speed of light squared gives you a huge number, so a lot of energy can be produced by a small particle of material and you see that when you watch a meteor burn up in the atmosphere."
Comet Catalina
Seronik said another celestial object that can be seen in the coming days is the comet Catalina, which was discovered in October 2013 by researchers working on a project designed to find comets and asteroids that might collide with Earth.
The path of the Comet Catalina in the month of December. The comet tracks north-northwest through Virgo and into Bootes. (skynews.ca)
"This is your one and only chance to see this particular comet because it has actually already swung around the sun … and is now on its outbound journey on its way out of the solar system," he said. "Once it leaves its gone forever, it's not coming back, so if you want to see this particular comet, it's time to do it."
Seronik said binoculars are needed to see the comet, which can be observed in the early morning hours not far from Venus, the brightest object in the sky besides the sun and moon.
"If you take your first and hold it out at arm's' length up against the sky, from the from the top knuckle to the bottom knuckle that's about 10 degrees, so about a fist's width above Venus, that's where the comet will be this weekend," he said.
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