Thank you, tiny space rocks. Because of you, the entire population of planet Earth will be treated to one of 2014’s most spectacular celestial displays. The Geminids meteor shower is the most active of the annual meteor showers—by a long shot—and it’s just about to peak.
Tonight, the shower might produce as many as 120 meteors per hour (though back in 2011, the Geminids hit a peak rate of 198 meteors per hour). Compare this count to the second most abundant shower, the Perseids, which take place in late August and top out at around 60 meteors per hour.
The annual December display is largely due to asteroid 3200 Phaethon, a three-mile wide chunk of rock that crosses the paths of all the inner rocky planets and travels closer to the sun than any other named asteroid. As ol’ 3200 heats up close to the sun during its 1.5-year orbit, it expels materials and forms a trail much like a comet (indeed, it is sometimes referred to as a “rock comet”). But that’s not the full story. Recent observations have shown that 3200 mostly expels dust as it is baked by the sun. And while this periodic “dusting” does help replenish the debris field, it’s not enough material to account for all the Geminids’ activity.