Large meteor shower to start Sunday night

If skies over the Bay Area are clear Sunday and Monday nights, the year’s most abundant shower of meteors will be visible among the stars long after dark.

They are the “shooting stars” of the Geminids, and they appear to come from the constellation Gemini, although the streaks of light that mark each meteor can appear anywhere in the sky.

The flashing objects should be visible at the rate of one or two a minute from 10 p.m. on both nights, peaking around 2 a.m., said Andrew Fraknoi, the astronomy chairman at Foothill College in Los Altos Hills.

“It’s more important to decide where to watch for them than when to watch for them,” he said. “The crucial issue is that meteors are faint, so you need a location where the sky is really dark — not only dark but clear.”

Fraknoi offers these tips as well:

“Don’t use a telescope or binoculars because your eyes are the best tools. And it takes patience, because meteors are not like fireworks, and several minutes can pass by without a single flash.”

“Don’t expect to find anything the minute you start looking, because it takes a good 15 minutes or more for eyes to adjust from indoor light to the night sky’s darkness.”

Although most meteor showers are the dusty debris shed by comets that heat up as they pass the sun in their long, looping orbits through the solar system, the Geminids are unique because their tiny fragments of rock come from a single big rock — an asteroid named 3200 Phaethon, about 3 miles in diameter.

The Geminid meteor shower was known by the ancients, but the asteroid itself was undiscovered until 1983, when astronomers detected it in data from a NASA infrared satellite named IRAS that was making an all-sky star survey.