[BAA-ebulletin 00756] PERSEID METEORS APPROACHING PEAK ACTIVITY

[BAA electronic bulletins service]

PERSEID METEORS APPROACHING PEAK ACTIVITY

Although the weather has been rather variable over the past few days,
observers across the British Isles have reported increasing Perseid meteor
activity. The Perseids are one of the most reliable showers of the year,
producing an abundance of fast, bright meteors.  This year there will be
little or no interference by moonlight, with New Moon occurring on August 6
and First Quarter on August 14.  
	The first Perseid meteors were detected in late July and the shower
will continue to be active until about August 21. The shower’s activity
displays a marked ‘kick’ around August 8-9 and steadily increasing observed
rates may be expected from now until the peak, which is expected at around
18h UT (19h BST) on August 12 this year.  This means that the two nights of
Sunday night to Monday morning (August 11-12) and Monday night to Tuesday
morning (August 12-13) will probably be equally productive for observers in
the UK. 
	Observers watching after midnight on August 11-12 should experience
increasing activity towards dawn, as the shower radiant at RA 03h 13m,  Dec.
+58° (near the Double Cluster, on the Perseus-Cassiopeia border) climbs
higher in the eastern sky. Activity should be just starting to decline by
the time darkness falls on Aug 12-13. 
	It is hoped that, weather permitting, observers will cover shower
activity on the nights to either side of the maximum, for example on the
Saturday night to Sunday morning (August 10-11) and Tuesday night to
Wednesday morning (August 13-14). The Perseids are also an ideal target for
digital imaging due to the relative abundance of bright meteors.
	The best observed rates are found when the Perseid radiant is
highest in the sky during the pre-dawn hours, but even in early evening the
radiant is already at quite a favourable elevation above the horizon. Under
cloudless skies, and in dark sites, observers can expect to see between 50
and 70 meteors each hour near the peak. Even in towns or cities observed
rates may still be around ten an hour in the early morning hours when the
radiant is high.
	Observations in recent years have revealed noticeable variations in
activity from year to year and we shall just have to wait and see what is in
store for us in 2013.
	The BAA’s visual meteor report forms, available as downloads in both
pdf and Excel formats, enable observers to record the details of each meteor
seen. These include: time of appearance (UT); apparent magnitude
(brightness); type (shower member, or random, ‘background’ sporadic);
constellation in which seen; presence and duration of any persistent train.
Other notes may mention flaring or fragmentation in flight, or marked
colour. Watches should ideally be of an hour’s duration or longer (in
multiples of 30 minutes). Observers are reminded to carefully record the
observing conditions and the stellar limiting magnitude.
	For further information please see the August BAA Journal, page 187.

	By whatever means you observe the Perseids this year, please submit
your results to the BAA Meteor Section via meteor at britastro.org.

This e-bulletin issued by:

Dr John Mason
Director, BAA Meteor Section
email: docjohn at dircon.co.uk

2013 August 9