In the United States, between about 12:30 and 4:30 a.m., as many as three to five meteors per minute were seen, with multiple meteors witnessed simultaneously at times, according to sky-watcher David Harvey, who viewed the show from Kitt Peak, outside Tucson, Arizona.
"Although I did not make an effort to accurately count the number of meteors I saw, I would estimate that the rate peaked at 120 or better [per hour] from my location," Harvey said.
Meteors are the result of mostly sand grain-size particles entering Earth's atmosphere at high speed. A quick streak of light—or "shooting star"—results when these particles burn up and superheat the air around them. (Take a solar system quiz.)
A meteor shower occurs when the Earth passes through debris clouds, causing tons of this cosmic dust to rain down on Earth.
This year's fireworks show was especially good, thanks to the moon setting just before the Geminids' peak, leaving behind dark skies in the predawn hours of Tuesday. (Learn about the phases of the moon.)