Cosmic show to light up the night skies before Christmas—How to watch

In one of the final cosmic hurrahs of the year, the Ursid shower is due, sending sparkling meteors shooting across the night sky in the lead-up to Christmas.

The Ursid meteor shower is forecast to peak late on December 22 and in the early hours on December 23, and may result in between five and 10 meteors being seen per hour in the sky.

The shower is active between December 17 and December 24 this year, according to EarthSky. It occurs at around the same time every year.

How to Watch the Ursid Meteor Shower

The Ursids will be best visible during the darkest hours on the night between December 22 and 23, in areas with lowest light pollution.

“Keep away from bright lights, as these will ruin your night vision, and drown out the meteors. It takes about 20 minutes for your eyes to fully adapt to the dark but a few seconds of bright light to lose it. If you want to use a torch, put some red film over the end (sweet wrappers are excellent for this),” Mark Gallaway, an astronomer and science educator at the Royal Observatory in Greenwich, told Newsweek. “Also, wrap up warm. It’s very easy to get cold when you are standing around under a clear sky.”

One roadblock preventing the ideal viewing of the meteor shower is the moon, which can drown out the fainter meteors if it’s nearing its full phase. Unfortunately, the full moon is due on December 26 this year, meaning that on December 22/23, it will be around 80 percent full. Other forms of light pollution can also mask the meteors: during the Geminids, the northern lights ended up outshining the meteors in some areas.

Where Will the Ursid Meteor Shower Be Visible?

The shower is so called due to its meteors appearing to originate in the constellation of Ursa Minor—also known as the Little Dipper—and is therefore best spotted from the Northern Hemisphere, though the Southern Hemisphere may also see a few meteors.

The frequency of meteors during the Ursids is a lot lower than some of the other popular showers, like the Geminids or Perseids, which can show up to 100s per hour. The latter end of the Geminids—which run between November 19 and December 24 this year—may still be visible in the sky at the same time as the Ursids’ peak, potentially increasing the number of meteors seen.

In the past, some Ursids have been much more active than others, with 120 meteors per hour being spotted in 1945, and 90 per hour in 1986, according to EarthSky.

What Causes the Ursid Meteor Shower?

The Ursids are a result of the Earth interacting with a comet called Comet 8P/Tuttle. This comet orbits the sun in a long, oval-shaped elliptical orbit that takes around 13.5 years, heating up as it approaches the sun and cooling down as it moves away. This heating of a comet causes it to leave a trail of rock and ice particles in its wake, resulting in a stream of particles being scattered across its orbital path.

If this path intersects with the orbit of Earth around the sun, then these particles may fall into the Earth’s atmosphere, burning up as they fall and forming the streaks of light we know as a meteor.

“Generally, meteor showers are caused by debris (small particles or meteoroids) from the cometary tails,” Robert Massey, deputy executive director at the U.K.’s Royal Astronomical Society, told Newsweek.

“Comets follow an orbital path around the Sun, and leave material in their wake. When the Earth encounters that material (typically annually) the result is that the debris enters the atmosphere at relatively high speed, burns up and heats the air around it. That results in a shower of brief, bright streaks of light—meteors or ‘shooting stars,’ with a meteor seen sometimes tens or even hundreds of times an hour. I should stress that meteors are seen all the time from random debris (usually about six times an hour), but showers are when activity is greatly enhanced.”

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