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The major meteor event in December is the Geminids but there's another shower later in the month that doesn't quite make as many headlines but on occasions can be quite good. It's the Ursids. With the radiant located close to Polaris the North Pole Star, the Ursids are a Northern Hemisphere shower. They are much less dramatic than the Geminids with only about 10 meteors per hour visible but on past occasions have shown significant bursts of activity and a re-occurrence may occur anytime.

This year's Ursid peak occurs on the night of December 22/23. The last quarter Moon rises around 3am and won't significantly interfere.

Parent comet

The comet that sources and is therefore responsible for the shower is 8P/Tuttle (also known as Tuttle's Comet or Comet Tuttle). It has a period of 13.6 years and during the last perihelion on January 27, 2008 was visible telescopically. On January 1, 2008 it passed Earth at a distance of 0.25282 AU (37,821,000 km or 23,501,000 miles) and anticipation was high that the 2007 and 2008 showers may produce much increased activity but that was not to be. In the end only a small increase was noted.

Comet 8P/Tuttle and M33 The Triangulum Galaxy (Paul Martinez / Philip Brents)

Radiant

The radiant for the Ursids meteors is located in the far northern constellation of Ursa Minor. With a declination of +76 degrees it's circumpolar from most northern sites. However, on the other hand it fails to rise from many southern sites. Positioned just a couple of degrees southeast of the radiant is Kochab (β UMi).

Ursids Radiant and Star Chart

Ursids Radiant and Star Chart - pdf format

What to expect

The best night to look for the Ursids is on December 22/23. Normally it has a Zenithal Hourly Rate (ZHR) of 10 although there have been at least two major outbursts in the past 70 years (1945 and 1986). During an outburst more than 50 meteors per hour can be seen, propelling the shower into the realms of some of the better annual meteor showers.

When observing meteors they can streak through the sky many degrees from the actual radiant so it's better not to look directly at it but scan a large area of surrounding sky. To confirm an Ursid trace the meteor and it will go all the way back to the radiant.

Looking north just after midnight from mid-northern latitudes on December 23rd (credit:- freestarcharts/stellarium)

Ursids 2016 Data Table

Meteor shower nameUrsids
Radiant ConstellationUrsa Minor
Dates17th December -> 26th December
Peak Date22nd December
RA (J2000)14hr 28m
Dec (J2000)+76d
Speed (km/s)33
ZHR 10 (occasionally up to 50)
Parent8P/Tuttle (comet)