Head for dark, clear skies tonight — overnight Dec. 13-14 — to see the shooting stars of the
Geminid Meteor Shower overhead.
The shower is likely to be the best meteor shower of 2018, and it will be visible in both hemispheres — though the Northern Hemisphere will have an advantage. While the August Perseid meteor shower is more famous, experts are saying to get outside for this one as well.
"Maybe [it's less well known] because it's cold for so many during this shower's peak," Diana Hannikainen, Sky & Telescope's observing editor, said in a statement. "But the Geminids are often the best display of 'shooting stars' all year."
According to Sky & Telescope, the Geminids are set to peak at 7:30 a.m. EST (1130 GMT) on Dec. 14, when Earth plunges through the thickest part of the trail of dust and debris left behind by the asteroid 3200 Phaethon as it orbits the sun. That means that the best times to watch are when it's dark in your local time zone surrounding that peak, such as just before dawn on Dec. 14.
But if you won't be up in those early hours, you can also start watching a couple hours after sunset; the moon will set at about 10:30 p.m. local time on Dec. 13, and about 11 p.m. local time on Dec. 14, so just look after that on either of those nights.
"If you've got a clear, dark sky with no light pollution, you might see a meteor streak across the sky every minute or two from 10 p.m. until dawn on the night of the peak," Hannikainen said.
The darker the skies, the more meteors you are likely to see, but some are bright enough to see in even less-than-favorable conditions. The meteors can appear all across the sky, but they'll appear to be flying away from the area of the bright star Castor in the Gemini constellation.
Leading up to the peak, fainter meteors are more common, and at the peak the brighter ones are, according to Sky & Telescope. Though they'll appear in fewer numbers, the week surrounding the Geminids' peak may still provide a good show.
The meteors are bits of material left behind by 3200 Phaethon — they burn up in Earth's atmosphere, creating streaks and fireballs in the night sky. 3200 Phaethon, a 3-mile-across (4.8 kilometers) object, orbits the sun every 1.4 years, ejecting rocky dust along its path. The asteroid passes closer to the sun than any other known asteroid, according to Sky & Telescope.
As Earth barrels through that dust and debris, its particles hit the atmosphere at 22 miles per second (35 km/s) and are vaporized in a fiery glow. Particles that hit straight-on, near the radiant, will have shorter streaks, whereas those grazing the atmosphere farther away from the radiant will leave longer streaks. (There may be more of those in the early evening, when the radiant is lower in the sky.)
To best take in the Geminids, dress warmly and prepared to be outside for a long time — it takes at least 20 minutes for your eyes to adjust to the dark. You'll see the most meteors if you lean back and look at as much of the sky as possible; don't be tempted to use a telescope or binoculars, because they'll restrict your field of view.
"Go out in the evening, lie back in a reclining lawn chair, and gaze up into the stars," Hannikainen said. "With the radiant rising in the evening, this is a good shower for younger observers who may have earlier bedtimes. But as always, it's good to remember to be patient."