The Geminid meteor shower, which produces similar hourly meteor rates to the Perseids in August, will be much better this year, thanks to the dark skies and the lack of an “outshining” moon. Plus, the Geminids yield slower and more colorful meteors at a time of year when low humidity often favors dry, clear nights and good visibility.
For the next few nights, you might still see a straggling Leonid meteor or two streak across the night sky, appearing as a flash of blue or white light. The Leonids result when debris left in the wake of comet Tempel-Tuttle, which slingshots around the sun every 33 years, burns up in our outer atmosphere.
Most years feature a trickle of meteors, but the show is famed for its periodic “meteor storms.” In 1966, a “blizzard” of shooting stars rained down on the night side of Earth, with meteor rates approaching 100,000 meteors or more per hour. That’s 20 to 30 per second. The sky was aglow with shooting stars.
It was an apocryphal but real display that lasted a few hours before vanishing with the breath of dawn. While a pair of impressive meteor outbursts occurred in 1999 and in 2001, no such prolific Leonid meteor storms are predicted in our lifetimes. Still, the Leonids do produce occasional fireballs, or shooting stars brighter than the planet Venus. NASA’s All-Sky Fireball Network has recorded numerous fireballs across the country each night this week.
The Geminids, on the other hand, don’t produce meteor storms, but they are reliably among the best meteor showers of the year. “Zenithal hourly rates,” an idealized number that calculates how many meteors pass over a clear, unobstructed location beneath a dark sky, routinely range from 75 to 125. Realistically, that means you’ll probably spot 20 or 30 per hour under ideal conditions.
Geminid meteors are instigated by 3200 Phaethon, a 3.6-mile-wide asteroid. The spaceborn pebbles, which are made of magnesium, sodium and iron-rich particles, zip overhead at 37 miles per second. Their luminosity comes from the burning compounds and a superheated cushion of air compressed in advance of the meteor that glows.
Mark your calendars for the night of Dec. 13 if you plan to hunt for Geminids. For those venturing out and about, you’ll want a clear, dark location. Beaches, fields, farmland and other spots far from light pollution are ideal.
When watching a meteor shower, there’s no place specific to look. If you trace back the tails of the shooting stars, all will converge at the “radiant point,” from which the meteors appear to emanate. The most visually striking meteors will be found 90 degrees away from the radiant, though. It’s like enjoying a fireworks display — you don’t look at where they’re launched from, but rather where they’ll dazzle.