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2017 December Alpha Draconids


Main Activity Dates Dec 4-13
Peak Rates Dec 8
Peak ZHR 3
Best Observed Rates

Pre-Moonrise / late in the night

Visibility each night (UK) Visible all night
Moonlight issues at Maximum Serious - Moon only a few days past Full

 

 

 

 

 

 

There has been some confusion in recent years regarding the activity period of this minor shower.

Originally, it was assigned a peak date of December 8th. There was, however, a later claim of a second peak from a similar radiant position on Dec 30th and to complicate things further, some software programs used in conjunction with video imaging systems have been assigning many (single-station observed) meteors in early January to this minor shower.

Two factors are probably responsible, at least in part, for this apparent later activity.

- one is that the software programs assign the shower a large radiant diameter of  9 degrees.

- the other is that located nearby is the radiant of the Quadrantid meteor shower - this is active from late December to mid-January and produces meteors with a similar speed.

Multi-station analyses, when possible, tend to re-assign most of these later single-station “December Alpha Draconids” to the Quadrantids.

This accompanying chart shows the radiant location for the established peak of Dec 8-9, with the horizon shown as for the middle of the night for UK based observers.

Moonlight will be a major issue for the Dec 8 peak in 2017, with the Moon being only a few days past Full.

Pre-moonrise, the radiant will be low in the northern sky. Late in the night when the radiant climbs high in the sky the Moon will also be high in the sky.