General Info

General information about the Geminids

The Geminids meteor shower is the final major meteor shower of the year and also the most consistent shower in terms of putting on fruitful display. This annual meteor shower has been observed for over 500 years and is active from December 7th through December 17th. The Geminids are distinguished by their multi-colored display. Observers below may be treated so several colors—65% white, 26% yellow, and the remaining 9%, green, blue, and red.

Meteors streak through the night sky at a moderate speed, which makes them less difficult to miss when compared to faster meteors. The Geminids are extremely bright and are every so often capable of producing fireballs.

While this annual spectacular appears to radiate from a constellation, they are actually caused by the Earth passing through the dust particles of the asteroid 3200 Phaethon. This is rare for meteor showers, as most originate from a comet. Each autumn, Earth passes into a trail of dust left by this asteroid, and as a result, all the dust and debris burning up in our atmosphere, travelling at a very fast 21.75 miles per second, produces the spectacle known as the Geminids meteor shower, or what are popularly recognized as “shooting stars”.

There's no danger to sky watchers, though. The fragile grains disintegrate long before they reach the ground. While the meteors are certainly bright, they are typically not much larger than a grain of sand. However, as they travel at immense speeds, these tiny particles put on an impressive show.

The moon-soaked Geminids in 2011

In 2011, the Geminids are best viewed on the night of December 13th though the morning hours of December 14th. Observers may also watch during the night of December 14th through the morning hours of December 15th. The Geminids are known for producing 100-150 meteors per hour during perfect conditions, but the moon will make that impossible this year.

This year, eager sky watchers who are fortunate enough to have completely clear skies may witness between 5 and 20 meteors per hour. (The time frame for the most intense activity is anticipated sometime around 19 UTC on December 14, 2011). As one can imagine, the less cloud cover, natural light from the moon, light pollution, and precipitation present, the greater the number of meteors you’ll have the chance of viewing.

Unfortunately, the large and bright waning gibbous moon (83% full) will coincide with the peak of the Geminids this year. This will lessen the number of meteors you’ll see streaking through the night sky. Nevertheless, observers will still be able to see all but the faintest meteors. The moon will rise in the middle of the evening and shine until dawn. While this year won’t be ideal to watch the Geminids, this is the final major meteor shower of the year, so those willing to stick it out in the cold (or warmth, for those in warmer environments) will be treated to a bright moon, and a few meteors in the night sky.

How do I know if the sky is dark enough to see meteors?

If you happen to live near a brightly lit city, if possible, we recommend that you drive away from the glow of city light. After you’ve escaped the glow of the city, find a dark, safe, and possibly isolated spot where oncoming vehicle headlights will not occasionally ruin your sensitive night vision. Look for state or city parks or other safe dark-sites. If you can see each star of the Little Dipper, your eyes have "dark adapted," and your chosen site is probably dark enough.

For the best view, meteor gazers should face in any direction away from constellation Gemini and the moon, which will appear close to the constellation. This way you won’t have the bright moon within your field of view. The constellation Gemini (The Twin) is the radiant of the Geminids meteor shower, which means that meteors appear to radiate from within the constellation. Correspondingly, the Geminids meteor shower is named after Gemini.

From within Gemini, the Geminids meteors appear to originate from Gemini’s bright stars, Castor and Pollux. For most meteor shower, observers would face the direction of the showers’ radiant, but this is not the case with the 2011 Geminids.

Unlike many of the other major meteor showers, the Geminids can be viewed early in the evening. This is due to the radiant (the constellation Gemini) being about 30 degrees above the eastern horizon by 9:00pm. Before you head out, remember to dress warmly and to get comfortable. Observing a meteor shower, especially one that occurs in less than ideal conditions, takes a lot of patience.

However, those who stick it out may be treated to a modest showing. We wish you a wonderful viewing experience, and hope that the last meteor shower display of 2011 packs in several surprises!