Watch the Geminid 'rock comet' meteor shower from anywhere

Monday, December 14, 2015, 11:06 AM - The annual Geminid meteor shower is at its peak on the nights of December 13 and 14. Here's your guide on watching the show, from your backyard or anywhere in the world.

Every year, around the middle of December, skywatchers are treated to the Geminid meteor shower, as Earth passes through a trail of rocky dust and debris left behind by an unusual resident of the inner solar system.

In 2015, the nights of December 13 and 14 are the times to watch, as that is when Earth passes through the densest part of the debris stream, and thus we see the greatest number of meteors. Viewing is expected to be especially good for this shower, as the meteors will have very little competition in the sky those nights.

Although some meteor showers can be washed out by a bright moon in the sky, for this one, there is only a very thin sliver of a crescent moon to contend with, and that will be setting in the west very shortly after sunset. This will leave observers with a nice dark sky, and those with chilly, dry weather conditions will likely be in for the best view.

Unfortunately, for much of Canada, weather is the main concern, due to a few systems tracking across parts of the country.

Watch from anywhere

Stuck under cloudy skies? Fortunately, the folks at the Slooh Community Observatory had us covered!

Watch at the top of the page, as they replay their Sunday night live broadcast of the Geminid meteor shower from various locations around the world. They featured live views of the night sky, images snapped of the meteors as they occur, and there were plenty of guests to provide commentary, along with fascinating facts about the science and even mythology of meteor showers.

For those who do happen to have clear skies tonight, the radiant for the Geminids - the point in the sky where the meteors appear to originate - rises in the east just after sunset, and tracks high across the sky throughout the night.

According to Peter Brown, an astronomer and meteor expert at Western University in London, ON, the Geminids are a very strong meteor shower, even stronger than the August Perseids.

This shower's "Zenith Hourly Rate" - basically the number of meteors visible under the absolute ideal conditions possible, including the meteor shower radiant being directly overhead - is usually quoted as being about 120 per hour. However, the actual rate seen by viewers, even under clear, dark skies is typically less. This is because many meteors are picked up by meteor radar, but are still too dim for our eyes to catch, or they are missed because we're glancing in the wrong direction (we focus on one meteor flash and miss another one going off in another part of the sky).

Even so, this is an impressive shower to watch.

"If the skies are clear, in the early evening, it would not be unheard of to see one meteor per minute," Brown wrote in an email to The Weather Network.

The position of the Geminids radiant in the eastern sky, during the evening hours of December 13 and 14. Credit: Stellarium/S.Sutherland

Although Sunday night and Monday night mark the peak of the shower, if the few days afterward happen to have the clearest skies for your area, it's worth it to get out on those nights instead, to see the show for yourself.

Unusual origin

Most of the meteor showers that occur during the year are caused by flecks of ice and dust-sized meteoroids left behind by comets. Geminid meteoroids, though, originate from 3200 Phaethon, an object that, so far, defies classification.

3200 Phaethon is on a comet-like orbit around the Sun, which takes it from inside the asteroid belt to within the orbit of Mercury and back out, once every 523 days. However, observations of this object show that it behaves more like an asteroid. It does not produce a coma or tails as it approaches or leaves the Sun, and astronomers have only reported a very diffuse tail of debris as it makes its closest pass around the Sun.

There are two competing explanations for this combination of orbit and composition.

It could be an "extinct" comet, a rocky remnant left behind after a comet loses all of its ice and volatile gases, similar to the one that flew past Earth on October 31, 2015.

Some astronomers call it a "rock comet" though, which is an asteroid that comes so close to the Sun in its orbit that its surface gets baked and cracked, causing it to blast out dust and debris into space.

There's even a bit of mystery behind this meteor shower. According to NASA, there is far too much debris in 3200 Phaethon's orbit to be accounted for by how much dust the rock has been seen putting off on its passes around the Sun. This could point to an impact in its distant past - either to knock it into its current orbit, or possibly to break it off of a larger object (main-belt asteroid Pallas?) and send it hurtling towards the Sun. If this is true, the meteors we see each year could be from a stream of tiny fragments from that ancient collision.

According to astronomer Peter Brown, this bright meteor over Hamilton - shown looped several times in the video above - was spotted on the night of December 9, 2015. Caused by a walnut-sized meteoroid from the Geminid stream hitting the atmosphere, it was travelling at over 120,000 km/h. Credit: Western University - Meteor Physics Group

Not seeing much? Wondering where these meteors are we're talking about? The problem may be light pollution.

Any competing source of light, such as the Moon in the sky, nearby street lamps or signs, car headlights or even your smartphone, can spoil your view of a meteor shower. These competing light sources will overwhelm the brightness of most meteors, meaning that we only see the very few brightest that flash by overhead.

The best place to watch a meteor shower from is some distance away from large urban centres, with as little ambient light nearby as possible. Be sure that you have a good view from horizon to horizon. Keep out of the influence of direct light, keep your smartphone in your pocket and allow your eyes roughly 30 minutes to adjust to the dark. Then look up.

You don't need to look at any particular part of the sky. Just sit or lay back and try to take in as much of the night sky as possible.

Want to see the absolute best places to watch from? Check your local light pollution conditions via LightPollutionMap.info

Sources: NASA | American Meteor Society | Western University | Slooh

Related Video: This great video by Science@NASA talks about the 2014 Geminid meteor shower, discussing some of the fascinating aspects of the shower and its parent body.