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December 17, 2019 might be your first night for seeing meteors in the annual Ursid meteor shower. This shower typically peaks around the December solstice, which, in 2019, comes on December 21 or 22, depending on your time zone. The shower’s peak morning is probably December 22. Look at the sky in the morning on the 22nd, after midnight and as late as possible before sunrise. Also any of the next few mornings should yield some Ursids as well. The meteor shower usually ends around December 26.
The Ursids produce a handful of meteors or shooting stars every hour, usually in the range of five to 10 per hour. A nearly moonless sky means good viewing, despite the low.
In some past years, the meteors have been more spectacular — in 1945 and 1986, for instance, 50 per hour were observed — but experts say that such events are rare.
In 2019, "we're not expecting an outburst," NASA meteor expert Bill Cooke told Space.com. "But the Ursids have surprised us before."
The Ursids have a sharp peak on the morning of Dec. 22, meaning that observers will see many more meteors on that day than on days before or after. Look at the sky in the morning on the 22nd, after midnight and as late as possible before sunrise. The meteor-shower radiant, which the meteors will appear to be flying away from, is near the bowl of the Little Dipper (Ursa Minor, near the celestial North Pole), and the radiant will climb higher in the sky in the pre-dawn hours.
Meteors will appear to be streaming out from the radiant, but they can show up all across the sky. Look a little bit away from the radiant, but not too far, to make sure that you catch sight of meteors with longer tails. That said, the Ursids are not known for leaving spectacular tails in the sky.
All meteors in annual showers have radiant points on our sky’s dome, and the showers often take their names from the constellations in which the radiant points lie. The Ursids radiate from Ursa Minor, which contains the Little Dipper asterism. If you trace the paths of the rather slow-moving Ursid meteors backward, they appear to come from the section of sky marked by the Little Dipper star Kochab.
The chart below shows the Big and Little Dippers around 1 a.m. when the Big Dipper is well up in the north-northeast.
Although the Little Dipper is circumpolar (out all night) at northerly latitudes, the star Kochab sits below Polaris, the North Star, at nightfall. Kochab (and all the Little Dipper stars) circle Polaris in a counterclockwise direction throughout the night, with this star reaching its high point for the night in the hours before dawn. The higher the radiant climbs in your sky, the more meteors that you’re likely to see.
This shower has been known to produce short bursts of over 100 meteors per hour. But typically the shower is much more low key than that. It might produce five meteors per hour at its peak.
Fortunately, the moon is now in waning phase. By the time of the Ursids’ peak on the morning of December 22 or 23, the moon will exhibit a fairly thin waning crescent, and shouldn’t too greatly intrude on what’s usually a low-key spattering of Ursid meteors.
By the way, some meteor showers, like the Perseids in August, have been watched each year at the same time for many centuries. But the Ursid meteor shower has been observed for only a single century. It was first observed around the turn of the 20th century, when a skywatcher noticed that some meteors seen around this time of year weren’t random in their direction of motion across our sky’s dome but instead appeared to radiate from near the star Kochab in the bowl of the Little Dipper asterism.
Bottom line: If you want to watch the Ursids, find a country location where you can camp out. Dress warmly! And plan to spend several hours reclining under a dark sky. The predawn hours are usually the most favorable.
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