Here’s our guide to the shower.
Where To Look, And When
Head outside in the mid-evening on Sunday. The meteors from the Geminids have their origin point in Gemini, so you’re most likely to spot one if you have a clear view of that constellation. It rises in the east around 6 p.m. local time, and should be visible from just about anywhere on Earth. (Though in the southern hemisphere you’ll have to wait for sunset!) Find a spot with a clear view of the eastern horizon, then look towards Gemini. It’s near the iconic constellation Orion, so if you can spot the three bright stars of his belt, that’s good enough. Here’s our finder chart:
Likely Awesomeness Rating: Very High
NASA is predicting an average of two meteors a minute over the course of the evening. Plus, the crescent moon will set at 7:30 (or thereabouts—earlier at higher latitudes, later at lower ones), so the sky will be nice and dark. Mix in the fact that Gemini rises in the early evening, and we’ve got a good, easy-to-watch shower in the offing. Keep an eye on the likelihood of clouds in your area with this map from the National Weather Service. Mouse over “Sunday evening 7 p.m.” in the sky cover column to see—in the U.S., anyway—whether you can expect clear skies.
Why Now?
Mid-December is when the Earth passes through the debris field of an asteroid called 3200 Phaethon. Small bits of ice and rock litter the asteroid’s path. As the Earth crosses the debris field, it runs into the pieces—and they burn up as they fall into the atmosphere. (The pieces are so small it’s unlikely they’ll reach the ground.) The Geminids are unusual: Most meteor showers are from comet debris, not asteroids. But 3200 Phaethon is an unusually icy asteroid, which also sweeps in closer to the sun than the planet Mercury. Since it orbits every 1.4 years, it passes through these parts pretty often. So it replenishes the shooting-star stuff regularly. And that’s a big part of why this shower promises to create such a show.