It’s December, and that means two things: Lots of looking back over the past year, and the year’s best meteor shower is coming. (Insert “brace yourself” joke.) Oh and also Santa everywhere and spending too much money on gifts.
Back to the point: Tonight the annual Geminid meteor shower peaks. Assuming weather allows, you’ll be able to see multiple tens of meteors per hour, with peak viewing falling sometime in the very early hours of Dec 14. I say this is the “best” meteor shower for a few reasons, all of which are completely subjective. For starters, it’s the most reliable: you’ll always see Geminids at their peak on Dec 13 and 14, though they’re visible in lower quantity as early as Dec 4 and as late as Dec 17. Secondly, the meteors move more slowly than, say, the Leonids, which makes them easier to spot. And their yellowish hue also makes them easier to see. Lastly, Geminids are best viewed without a telescope, which means the spectacle is available to everyone. If you’re in a dark area with little or no cloud cover, the hours of midnight to 2am (in your local time, whatever that may be) is prime viewing for the shower, should you decide to brave the cold or set up shop near a large window.
Despite the shower’s reliability and easy visibility, the coolest thing about the Geminids is that their source, an asteroidal object named 3200 Phaethon, is something of a mystery. Its orbit is like that of a comet, but it’s clearly a rocky body, like an asteroid. Because of these mixed cometary and asteroidal features, Phaethon is sometimes called a “rocky comet.”
Geminid meteors set to light up winter sky [Phys.org]
Geminids’ entry in the IMO Meteor Shower Calendar 2012 [International Meteor Organization]
Geminids: How Low Do They Go? [NASA Blogs]
Brilliant Geminid Meteor Shower Peaks Tonight [Space.com]