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2017 Quadrantids

A major meteor shower that produces a high activity, but rather narrow, peak

Main Activity Dates Jan 1 - 6
Peak Rates Jan 03d 14h UT
Peak ZHR 80 +
Best Observed Rates 4am to dawn and dusk to 18h on Jan 3
Visibility each night (UK) Visible all night - radiant highest around dawn
Moonlight issues at Maximum Some interference early evening

 

 

 

 

 

The year starts with an intense, but short-lived, meteor shower : the Quadrantids.

Although some outliers can be identified by imagers before and after the dates given above, Quadrantid activity is really only evident to visual observers between Jan 1 and Jan 6 each year, with the peak occurring at some time during Jan 3-4. The shower produces a good number of bright trained meteors.

The chart below shows the location of the Quadrantid radiant relative to the stars of Draco, northern Bootes and the Plough, with the UK horizon shown for around 22h GMT.

With the peak being so narrow, we need several factors to be in our favour to see the Quadrantids at their very best:

- the peak needs to occur during the hours of darkness

- the radiant needs to be high in the sky

- the Moon needs to be out of the way

In 2017, only one of these requirements will be reasonably well met:

- the Moon is "only" a thick crescent (in the SW sky), setting at around 22h local time on the 3rd.

whereas for the other two:

- the peak is predicted to occur during the hours of daylight for UK based observers.

- the pre-dawn skies, when the radiant is highest, are many hours away from the time of the peak.

Having said that ... although these latter two factors are not well met, all is not lost and it will still be worth making the effort to observe this year's Quadrantids if skies are clear. The west coast of North America is best placed, while for observers in Asia it will also be night time but the radiant will be lower in the sky).

More precisely:

-  the peak is predicted to occur during the afternoon (UK time) of Tuesday Jan 3rd, at approx 14h UT

 - for UK based observers, there is a choice between the pre-dawn skies of Jan 3 (when the radiant is very high in the sky, but we are still more than 7 hours away from the predicted peak) and the early evening skies of Jan 3 (closer to the peak, but with the radiant being much lower in the sky, leading to some meteors being "lost" in the haze or below the horizon). Observers at more northerly latitudes will benefit from the earlier sunset (and thus being able to observe closer to the peak) and also by having a slightly higher radiant altitude.

- bear in mind also, that although the Moon will be present in the early evening sky, it will be sinking progressively lower in the SW sky, whereas you will most likely be monitoring the NE sky. The pre-dawn sky will be moon-free.

Recent ZHR values:

Peak Quadrantid ZHRs seem to vary from year to year. In 2012, the peak ZHR only reached around 80, whereas in 2009 the peak was broader with the ZHR exceeding 100. The most recent year in which the Quadrantid peak was well observed was 2014. The IMO activity curve for the 2014 Quadrantids http://www.imo.net/members/imo_live_shower?shower=QUA&year=2014  suggests that a particularly strong return was seen, with the peak ZHR probably exceeding 150. Observations in 2015 were severely hindered by a bright Moon. The 2016 Quadrantids were better seen, but the IMO activity curve included no observations close to the predicted peak time of 08h UT - the ZHR had reached about 70 an hour before this time. Observed hourly rates will, of course, be lower than the ZHR value, but you can maximise the number that you see by choosing a dark observing site with a clear view of the sky.

The Quadrantid radiant, being located at Dec +49, is circumpolar for observers north of latitude 41 N. It is lowest in the sky at around 20h local time and highest at the end of night. Few observers will have the stamina to stay out all night, but another option (for those who can drag themselves from their warm bed!) is to set your alarm for 3am or 4am and then observe from then until dawn with the radiant high in the sky.