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The best chance to see the strongest meteor shower of the year is on the way this week.
The Geminids, known for their bright, intensely colored meteors, have been streaking across the night sky since late November, with the shower peaking on the night of December 13-14. according to the American Meteor Society.
“If I had to pinpoint one (meteor shower) as the best of the year, year after year, it would be the Geminids,” said Robert Lunsford, coordinator of the society’s fireball report. “Normally, let’s say from the suburban area, under good conditions, you could probably see 30 to 40 meteors (per hour).”
With clear skies and no bright lights in the way, the Geminids can appear at a rate of about 120 visible meteors per hour. according to NASA. However, there is no escaping the great lighthouse in the sky that will obscure most of the fainter meteors this year: the moon will shine at 72% of its fullness, according to the American Meteor Society.
“It’s still going to be a good shower, even with the moon out,” said Bill Cooke, leader of NASA’s Meteoroid Environment Office. “Find a decently dark sky, find something to block the moon, maybe a building or a tree, and look away from the moon up to the sky.”
First observed in the mid-19th century, the shower initially delivered only 20 visible meteors per hour at most. Since then, the Geminids have reappeared each year, growing stronger in number. By the 1960s, the event had outgrown the substantial august perseids, once the strongest shower with hourly rates of 50 to 100 meteors.
It’s unclear how the Geminids might change in the foreseeable future, Cooke said, with some models indicating the shower will increase in intensity and others estimating a gradual decline over the next few decades.
The Geminids are unique in that their source is the asteroid 3200 Phaethon, while most other meteor showers are born from debris from icy comets. That’s why Geminid streams can be unpredictable, because it’s harder to model asteroid breakups, Cooke said.
Asteroid 3200 Phaethon is unusual in its own right, behaving like a comet when it approaches the sun. It also has an orbit, which it completes every 1.4 years or so, that is closer to the sun than any other asteroid. When 3200 Phaethon is close to Earth, the asteroid spews its dusty debris, hence the Geminids display.
The Geminids are active from November 19 to December 24. according to EarthSky, but their hourly rates don’t start hitting double digits until December 10, Lunsford said.
The shower is known to be familiar and a good one for young North American viewers to watch since it is the only important shower that exhibits the greatest activity before midnight. The meteors appear to radiate from the constellation Gemini, which will rise in the sky around 10 pm ET, Lunsford said.
“You can watch when the radiant is at its highest, which is between 1 a.m. and 2 a.m. ET in moonlight, or you can try to see it earlier in the evening when the moon is still below the horizon. “Lunsford said. “Rates will probably be pretty similar at those times as well.”
The Geminids will be visible from all parts of the world, but for the southern hemisphere, it is best to view towards the middle of the night at 2 am local time, as the radiant will need to be at its highest point to be seen. The position of the radiant will be low on the horizon and will also cause meteors to appear at a reduced rate, Lunsford said.
According to data from NASA’s meteorite camera, The Geminid shower is among the best for producing fireballs, meteors that are brighter than the planet Venus, second only to the Perseids, Cooke said. The largest and brightest Geminid meteors are often said to have a greenish color.
Moonlighting has affected Geminids viewing for the past two years, but the meteor shower is expected to occur around a new moon in 2023, creating perfect viewing conditions.
“When you see a meteor burn up in Earth’s atmosphere, you’re looking at something that’s been in space for a long time,” Cooke said. “From a scientific perspective, by studying it, we can learn something about what makes up those comets. To the casual observer, they make quite a fireworks display: meteor showers are nature’s fireworks.”
The next and last major annual meteor shower of 2022 will be the Ursids, which will peak on the afternoon of December 22. according to EarthSky.
