Don’t miss the Quadrantid meteor shower peak at UK dawn on 4 January 2020

By Ade Ashford

The Quadrantid meteor shower is rich but short-lived, so observers in the UK and Western Europe are likely to get the best views looking east between 6am and the first light of nautical dawn around 7am GMT on Saturday, 4 January 2020. This simulated view shows a quadrant of the sky centred on southeast as seen from the heart of the British Isles at 6am GMT, which is two hours before the predicted maximum but the start of UK astronomical twilight. AN graphic by Ade Ashford.
The year 2020 looks set to be a good one for the three major annual meteor showers. The year kicks off with one of the best, the Quadrantids, peaking at UK dawn on Saturday, 4 January after an 8-day-old waxing Moon has long set. The Perseids maximum of 12 August coincides with a waning lunar crescent, while the Geminids of 14 December peak at New Moon.

Having reviewed the New Year’s major meteor shower prospects in an instant, let us return to the Quadrantids, a shower of shooting stars named after the extinct star group of Quadrans Muralis (the mural quadrant) that used to sit between our present-day constellations of Boötes and Draco. For its 28 December to 12 January duration, the Quadrantid radiant — the point in the sky from which the meteors appear to originate – lies in northern Boötes.

An extinct comet?
The source of the Quadrantids is likely a small near-Earth asteroid/comet known as (196256) 2003 EH1 that was discovered on 6 March 2003 at the Anderson Mesa Station in Arizona. An Amor-class body, 2003 EH1 completes a circuit of the Sun every 5.52 years in a highly inclined, eccentric orbit and last came to perihelion on 18 September 2019. Probably an extinct comet, it is the scattered debris from 2003 EH1 that Earth intersects in early January each year.

A particularly rich shower for 2019?
Given that progenitor body 2003 EH1 was closest to the Sun in September 2019, could this be a bumper year for the Quadrantids? Only time will tell, but it’s a shower that routinely provides around 80 shooting stars per hour — if you happen to be watching at just the right time. They are slow to medium speed meteors, formed from particles of 2003 EH1 entering Earth’s atmosphere with velocities of around 43 kilometres per second (96,000 mph), with brighter Quadrantids often appearing yellow and blue. About ten percent of these will leave persistent glowing trails too.

When and how to observe the Quadrantids
While they have the potential to rival rates of the August Perseids or the December Geminids, the Quadrantids are often overlooked since the peak activity occurs within a four-hour window centred on a short, sharp maximum. The International Meteor Organisation (IMO) predicts that the shower will peak at 8h UT (8am GMT) on Saturday, 4 January 2020. If this holds true it favours North American observers around local midnight, or Western European skywatchers at astronomical dawn.

The Quadrantid radiant is circumpolar for temperate northern latitudes such as the British Isles, which means that it doesn’t set. While this means that you can see Quadrantids at any time of night in the first few days of January, recall that the period of peak intensity is brief. Observers in the British Isles should make the most of any clear skies from 12am on 4 January, but particularly between 6am and the first light of nautical dawn around 7am GMT, directing their attention towards the eastern sky.

Faint Quadrantids are the most plentiful, so to maximise your chances you should find a safe location that is as far removed from streetlights and other sources of light pollution as you can and allow 20 minutes for your eyes to become fully dark adapted. The 8-day-old waxing gibbous Moon sets around 1am GMT on 4 January, so moonlight won’t be an issue.