The Geminids Are Now Playing in a Sky Near You
The Geminids, which peak during mid-December each year, are considered to be one of the best and most reliable annual meteor showers.Â
This month, theyâre active from Dec. 4-17, and peak the evening of Dec. 13-14 for a full 24 hours, meaning more worldwide meteor watchers will get to enjoy the show.Â
Below are 10 things to know about this beautiful spectacle.
From our resident night sky expert, Jane Jones: If you can see Orion and Gemini in the sky, youâll see some Geminids. Expect to see about 60 meteors per hour before midnight on Dec. 13 and from midnight-3:30 a.m. on Dec. 14 from a dark sky. Youâll see fewer meteors after moonrise at 3:30 a.m. local time. In the southern hemisphere, you wonât see as many, perhaps 10-20 per hour, because the radiantâthe point in the sky where the meteor shower appears to originateânever rises above the horizon.
Kids can join in on the fun as early as 9 or 10 p.m. Youâll want to find an area well away from city or street lights. Come prepared for winter temperatures with a sleeping bag, blanket, or lawn chair. Lie flat on your back and look up, taking in as much of the sky as possible. After about 30 minutes in the dark, your eyes will adapt and youâll begin to see meteors. Be patientâthe show will last until dawn, so you have plenty of time to catch a glimpse.
The Geminids werenât always such as a spectacular show. When they first began appearing in the mid-1800s, there were only 10-20 visible meteors per hour. Since then, the Geminids have grown to become one of the major showers of the year.
4. Remind meâwhere do meteor showers come from?
Meteors come from leftover comet particles and bits from asteroids. When these objects come around the Sun, they leave a dusty trail behind them. Every year, the Earth passes through these debris trails, which allows the bits to collide with our atmosphere, where they disintegrate to create fiery and colorful streaks in the sky.
While most meteor showers come from comets, the Geminids originate from an asteroid: 3200 Phaethon. Asteroid 3200 Phaethon takes 1.4 years to orbit the Sun once. It is possible that Phaethon is a âdead cometâ or a new kind of object being discussed by astronomers called a ârock comet.â Phaethonâs comet-like, highly-elliptical orbit around the Sun supports this hypothesis. That said, scientists arenât too sure how to define Phaethon. When it passes by the Sun, it doesnât develop a cometary tail, and its spectra looks like a rocky asteroid. Also, the bits and pieces that break off to form the Geminid meteoroids are several times denser than cometary dust flakes.
3200 Phaethon was discovered on Oct. 11, 1983 by the Infrared Astronomical Satellite. Because of its close approach to the Sun, Phaethon is named after the Greek mythological character who drove the Sun-god Heliosâ chariot. Phaethon is a small asteroid: its diameter measures only 3.17 miles (5.10 kilometers) across. And we have astronomer Fred Whipple to thankâhe realized that Phaethon is the source for the Geminids.
The Geminidsâ radiant is the constellation Gemini, a.k.a. the âTwins.â And, of course, the constellation of Gemini is also where we get the name for the shower: Geminids.
8. In case you didnât know.Â
The constellation for which a meteor shower is named only helps stargazers determine which shower theyâre viewing on a given night; the constellation is not the source of the meteors. Also, donât just look to the constellation of Gemini to view the Geminidsâtheyâre visible throughout the night sky.
9. And in case you miss the show.Â
Thereâs a second meteor shower in December: the Ursids, radiating from Ursa Minor, the Little Dipper. If Dec. 22 and the morning of Dec. 23 are clear where you are, have a look at the Little Dipperâs bowlâyou might see about 10 meteors per hour.
10. Endless opportunities. There are so many sights to see in the sky. Use the Night Sky Network, the Solar System Ambassadors, and the Museum Alliance to look up local astronomy clubs, and join them for stargazing events in town, and under dark skies.
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