BAA electronic bulletin
HERE COMES THE PERSEID METEOR SHOWER
With the generally fine, clear weather that we have been experiencing across
much of the British Isles, observers are reporting increasing Perseid meteor
activity. The Perseids are one of the most reliable showers of the year,
producing an abundance of fast, bright meteors, many with persistent trains.
This year observing conditions are ideal because there will be no
interference at all by moonlight, with New Moon occurring on August 11 only
two days before the peak, and the maximum occurs mainly over a weekend which
is very convenient.
Video meteor observer David Dunn (Livarot, Calvados, Normandy, France)
recorded his first Perseid meteor on July 16 and rates are now rising
slightly night-by-night. The shower will continue to be active until about
August 24. The shower's activity displays a marked 'kick' around August 8-9
and steadily increasing observed rates are likely from then until the peak,
which is expected at around 01h UT (02h BST) on Monday, August 13 this year.
This means that the three nights of Saturday night to Sunday morning (August
11-12), Sunday night to Monday morning (August 12-13) and Monday night to
Tuesday morning (August 13-14)should all be highly productive for observers
in the British Isles.
Observers watching after 2100h UT on August 12-13 should experience
increasing activity towards midnight and in the pre-dawn hours of August 13,
as the shower radiant at RA 03h 11m, Dec. +58° (near the Double Cluster, on
the Perseus-Cassiopeia border) climbs higher in the eastern sky. Activity
should be starting to decline by the time darkness falls on Aug 13-14.
It is hoped that, weather permitting, observers will cover shower activity
on the nights to either side of the maximum, including the Friday night to
Saturday morning (August 10-11) the first night of the peak weekend. The
Perseids are an ideal target for digital imaging due to the relative
abundance of bright meteors, although exposures will need to be kept quite
short if you are imaging from a site with any light pollution.
The best observed rates are found when the Perseid radiant is highest in the
sky during the pre-dawn hours, but even in the mid-evening from 2100h the
radiant is already at quite a favourable elevation above the horizon. Under
cloudless skies, from a dark site, observers can expect to see between 40
and 60 meteors each hour near the peak. Even in towns or cities observed
rates may still be around 10 to 20 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 there was a brief but well recorded outburst in
Perseid rates in 2016 (see J. Brit. Astron. Assoc. 126(5), 264-265). No such
enhancements are expected in 2018, but there may possibly be an encounter
with an accumulation of dust grains in a mean-motion resonance at around 20h
UT on August 12, although whether this will be detectable is uncertain.
We shall just have to wait and see what is in store for us in 2018.
Meteor observing should be viewed, first and foremost, as a source of
enjoyment for the observer(s). Whatever the approach and specific techniques
applied, meteor observing can still produce unexpected results, and the only
way to make sure you don't miss out is to go out and observe!
By whatever means you observe the Perseids this year, please submit your
results to the BAA Meteor Section via meteor@britastro.org.
Please note that the Section Director will be away on Dartmoor from August
5th to 13th.
HERE COMES THE PERSEID METEOR SHOWER
With the generally fine, clear weather that we have been experiencing across
much of the British Isles, observers are reporting increasing Perseid meteor
activity. The Perseids are one of the most reliable showers of the year,
producing an abundance of fast, bright meteors, many with persistent trains.
This year observing conditions are ideal because there will be no
interference at all by moonlight, with New Moon occurring on August 11 only
two days before the peak, and the maximum occurs mainly over a weekend which
is very convenient.
Video meteor observer David Dunn (Livarot, Calvados, Normandy, France)
recorded his first Perseid meteor on July 16 and rates are now rising
slightly night-by-night. The shower will continue to be active until about
August 24. The shower's activity displays a marked 'kick' around August 8-9
and steadily increasing observed rates are likely from then until the peak,
which is expected at around 01h UT (02h BST) on Monday, August 13 this year.
This means that the three nights of Saturday night to Sunday morning (August
11-12), Sunday night to Monday morning (August 12-13) and Monday night to
Tuesday morning (August 13-14)should all be highly productive for observers
in the British Isles.
Observers watching after 2100h UT on August 12-13 should experience
increasing activity towards midnight and in the pre-dawn hours of August 13,
as the shower radiant at RA 03h 11m, Dec. +58° (near the Double Cluster, on
the Perseus-Cassiopeia border) climbs higher in the eastern sky. Activity
should be starting to decline by the time darkness falls on Aug 13-14.
It is hoped that, weather permitting, observers will cover shower activity
on the nights to either side of the maximum, including the Friday night to
Saturday morning (August 10-11) the first night of the peak weekend. The
Perseids are an ideal target for digital imaging due to the relative
abundance of bright meteors, although exposures will need to be kept quite
short if you are imaging from a site with any light pollution.
The best observed rates are found when the Perseid radiant is highest in the
sky during the pre-dawn hours, but even in the mid-evening from 2100h the
radiant is already at quite a favourable elevation above the horizon. Under
cloudless skies, from a dark site, observers can expect to see between 40
and 60 meteors each hour near the peak. Even in towns or cities observed
rates may still be around 10 to 20 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 there was a brief but well recorded outburst in
Perseid rates in 2016 (see J. Brit. Astron. Assoc. 126(5), 264-265). No such
enhancements are expected in 2018, but there may possibly be an encounter
with an accumulation of dust grains in a mean-motion resonance at around 20h
UT on August 12, although whether this will be detectable is uncertain.
We shall just have to wait and see what is in store for us in 2018.
Meteor observing should be viewed, first and foremost, as a source of
enjoyment for the observer(s). Whatever the approach and specific techniques
applied, meteor observing can still produce unexpected results, and the only
way to make sure you don't miss out is to go out and observe!
By whatever means you observe the Perseids this year, please submit your
results to the BAA Meteor Section via meteor@britastro.org.
Please note that the Section Director will be away on Dartmoor from August
5th to 13th.
This e-bulletin issued by:
Dr John Mason
Director, BAA Meteor Section
email: docjohn@dircon.co.uk
4th August 2018
BAA-ebulletin mailing list visit:
http://lists.britastro.org/
Dr John Mason
Director, BAA Meteor Section
email: docjohn@dircon.co.uk
4th August 2018
BAA-ebulletin mailing list visit:
http://lists.britastro.org/
(c) 2018 British Astronomical Association http://www.britastro.org/
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Good Clear Skies
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Astrocomet
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Colin James Watling
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Various Voluntary work-Litter Picking for Parish Council (Daytime) and also a friend of Kessingland Beach (Watchman)
--
--
Real Astronomer and head of the Comet section for LYRA (Lowestoft and Great Yarmouth Regional Astronomers) also head of K.A.G (Kessingland Astronomy Group) and Navigator (Astrogator) of the Stars (Fieldwork)
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Lyra Main Website: http://www.lyra-astro.co.uk/
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