Many amateur astronomers consider the Geminids to be the best meteor show of the year. Its only rivals are the Perseids in August and the Leonids in November.

The Geminids are produced by debris left behind by the asteroid 3200 Phaeton (also spelled Phaethon), which was discovered in 1983. The “3200” means Phaeton was the 3200th asteroid to have its orbit precisely known. Phaeton is named after Phaethon, the son of Sun-God Helios.

Phaeton comes closer to the sun than any other named asteroid. It has a dust tail and has been seen ejecting dust. Shortly after Phaeton was discovered, the famous astronomer Fred Whipple (1906-2004) noted the orbit of Phaeton was similar to the orbit of Geminid meteors. Whipple developed the modern theory for comet composition known as the “dirty snowball” hypothesis in which comets consist of various frozen materials “ices” mixed with dust.

Unfortunately, the Geminids this year peak on Tuesday, Dec. 13 into the next morning when the full moon sitting between Gemini and Orion will obscure many of the fainter meteors.

However, the Geminids are often bright and numerous, and there may be a good show. You can start observing in the early evening on the 13th as Gemini is well above the horizon by 8 p.m. Bundle up, get a comfortable chair, have coffee and hot chocolate at hand, look toward the east and enjoy the show.

Contact Tim Hunter at

skyspy@tucson.com