This movie shows a very bright Geminid meteor. This meteor was seen in December 2002.
Image courtesy George Varros.

Geminid Meteor Shower

The Geminid meteor shower happens every year in December. Meteor showers are times when you can see many meteors or "shooting stars" in one night. There are several meteor showers each year. Most meteor showers can be seen for several nights. Usually, there is one night when you can see the most meteors. That night is called the "peak" of the meteor shower. The peak of the Geminid shower is around December 14th.

During a meteor shower, it looks like all of the meteors shoot outward from one place in the sky. That point in the sky is called the "radiant" of the meteor shower. Each shower has a different radiant. The radiant for the Geminid shower is in the constellation Gemini. That is why this shower is called the "Geminids".

If you want to see Geminid meteors, go outside at night on December 14th or one of the nights just before or after that date. You can see more meteors if you can watch from someplace very dark, away from street lights. If you are lucky, you might see as many as 100 meteors in an hour!

Most of the Geminid meteoroids are very, very small - about the size of a grain of sand! However, they are moving very, very fast - around 35 km/s (about 78,000 mph)! When they hit Earth's atmosphere, they burn up and glow; the glowing trails they leave behind for a second or two are what we see as meteors.

Can you guess where meteors come from? Most meteoroids in meteor showers are actually dust from a comet! When a comet gets near the Sun and heats up, its ices melt and dust trapped in the ice escapes into space. The dust spreads out over the comet's orbit. When Earth crosses the comet's orbit, we run into the dust - and see a meteor shower!

The Geminids are a strange meteor shower. People have known about most of the big meteor showers for many, many years. But not the Geminids! The first time anyone noticed the Geminids was in 1862. At that time, there were only about 15 meteors per hour in the Geminids. Astronomers started looking for the comet that the Geminids came from. They couldn't find one! Finally, in 1983 a satellite named IRAS (Infrared Astronomical Satellite) discovered an object in the right orbit to make the Geminids. The object is named 3200 Phaethon. The strange object looks more like an asteroid than a comet. Maybe 3200 Phaethon is an asteroid that crashed into another asteroid, making a cloud of dust and small rocks. Maybe that cloud is what makes the Geminid meteor shower. Or maybe 3200 Phaethon isn't an asteroid after all. Maybe it is an old, "dead" comet that has lost all of its ice. Scientists aren't quite sure which is true.

Last modified February 3, 2010 by Randy Russell.

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Meteor Showers

A meteor shower is an astronomical event during which many meteors can be seen in a short period of time. Most meteor showers have a peak activity period that lasts between several hours and a couple of...more

Meteors

Meteors are streaks of light, usually lasting just a few seconds, which people occasionally see in the night sky. They are sometimes called "shooting stars" or "falling stars", though they are not stars...more

When a Comet comes close to the Sun

When comets are kicked out of the Oort Cloud, they begin a passage into the solar system, spinning and tumbling as they come. The trajectory which they acquire can be hyperbolic, parabolic, or elliptic...more

Elliptical Orbits

You may think that most objects in space that orbit something else move in circles, but that isn't the case. Although some objects follow circular orbits, most orbits are shaped more like "stretched...more

Orionid Meteor Shower

The Orionid meteor shower happens every year in October. Meteor showers are times when you can see many meteors or "shooting stars" in one night. There are several meteor showers each year. Most meteor...more

Leonid Meteor Shower

The Leonid meteor shower is one of several major meteor showers that occur on roughly the same date each year. The Leonids typically "peak" (are at their greatest level of activity) in mid to late November....more

Geminid Meteor Shower

The Geminid meteor shower happens every year in December. Meteor showers are times when you can see many meteors or "shooting stars" in one night. There are several meteor showers each year. Most meteor...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA