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BAA electronic bulletin
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LYRID METEOR SHOWER NEARS PEAK
The annual Lyrid meteor shower peaks this weekend on the night of April
21-22 when Earth passes through a stream of debris from Comet C/1861G1
Thatcher. The incoming Lyrid meteoroids have atmospheric entry velocities of
49 km/s, and Lyrid meteors appear swift. A fair proportion are bright, and
some leave persistent ionisation trains.
The April Lyrid shower, while relatively modest, brings a welcome upturn in
rates for a few nights, particularly around the maximum - this year expected
just before dawn on Sunday, April 22 - normally producing observed rates of
perhaps 6-8 meteors/hr under the clearest and darkest conditions when the
radiant is well up in the sky, corresponding to a corrected Zenithal Hourly
Rate (ZHR) around 10. Activity is about this level for 12 hours or so
centred on the maximum. At other times, observed Lyrid rates may be only 2-3
meteors/hr.
The best observed Lyrid rates will typically be found after midnight, when
the radiant (RA 18h 08m Dec +32°) located some 10 degrees south-west
of Vega, near the Lyra/Hercules border, climbs higher in the sky. The
radiant elevation approaches a very respectable 66 degrees by 0300 hrs local
time.
This year's peak coincides with a new Moon, so there will be absolutely no
interference by moonlight. The promise of a good Lyrid display has prompted
NASA to plan an unusual 3D meteor photography experiment combining
observations from the ground, a research balloon, and the International
Space Station. More details are available on:
http://science.nasa.gov/science-news/science-at-nasa/2012/18apr_lyrids/
Although Lyrid activity is generally rather modest, unmapped filaments of
dust laid down by the comet occasionally trigger outbursts in rates - most
recently in 1982 when, for a couple of hours, a ZHR around 200 was attained.
While there is no expectation of enhanced activity in 2012, the Lyrids have
sprung surprises on us in the past, and remain a shower very much worth
observing.
This e-bulletin issued by:
John W. Mason, Director, BAA Meteor Section
2012 April 20
==========================================================
BAA-ebulletin mailing list or visit:
http://lists.britastro.org/mailman/listinfo/baa-ebulletin
(c) 2012 British Astronomical Association http://www.britastro.org/
==========================================================
BAA electronic bulletin
==========================================================
LYRID METEOR SHOWER NEARS PEAK
The annual Lyrid meteor shower peaks this weekend on the night of April
21-22 when Earth passes through a stream of debris from Comet C/1861G1
Thatcher. The incoming Lyrid meteoroids have atmospheric entry velocities of
49 km/s, and Lyrid meteors appear swift. A fair proportion are bright, and
some leave persistent ionisation trains.
The April Lyrid shower, while relatively modest, brings a welcome upturn in
rates for a few nights, particularly around the maximum - this year expected
just before dawn on Sunday, April 22 - normally producing observed rates of
perhaps 6-8 meteors/hr under the clearest and darkest conditions when the
radiant is well up in the sky, corresponding to a corrected Zenithal Hourly
Rate (ZHR) around 10. Activity is about this level for 12 hours or so
centred on the maximum. At other times, observed Lyrid rates may be only 2-3
meteors/hr.
The best observed Lyrid rates will typically be found after midnight, when
the radiant (RA 18h 08m Dec +32°) located some 10 degrees south-west
of Vega, near the Lyra/Hercules border, climbs higher in the sky. The
radiant elevation approaches a very respectable 66 degrees by 0300 hrs local
time.
This year's peak coincides with a new Moon, so there will be absolutely no
interference by moonlight. The promise of a good Lyrid display has prompted
NASA to plan an unusual 3D meteor photography experiment combining
observations from the ground, a research balloon, and the International
Space Station. More details are available on:
http://science.nasa.gov/science-news/science-at-nasa/2012/18apr_lyrids/
Although Lyrid activity is generally rather modest, unmapped filaments of
dust laid down by the comet occasionally trigger outbursts in rates - most
recently in 1982 when, for a couple of hours, a ZHR around 200 was attained.
While there is no expectation of enhanced activity in 2012, the Lyrids have
sprung surprises on us in the past, and remain a shower very much worth
observing.
This e-bulletin issued by:
John W. Mason, Director, BAA Meteor Section
2012 April 20
==========================================================
BAA-ebulletin mailing list or visit:
http://lists.britastro.org/mailman/listinfo/baa-ebulletin
(c) 2012 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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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)
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Profile: http://www.google.com/profiles/astrocomera
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Lyra Website: https://sites.google.com/site/lyrasociety/
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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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Information -- And More Info
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Information -- And More Info
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