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 Post subject: Lyrids 2008
PostPosted: Wed Apr 16, 2008 9:34 pm 
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Earth is just moving into the outer edge of the Lyrid meteoroid stream today (April 16), with the shower expected to peak on April 21-22, perhaps around 05h UT, but almost certainly at sometime between 21h-08h UT then. Though this extended interval is partly overnight for Britain, the waning gibbous Moon around Libra (full on April 20) will be nicely visible by the time the Lyrid radiant has risen to a usable elevation, after 22:30 UT or so. This is not good news for visual observers! The radiant's (and the Moon's!) visibility improves throughout the night, the radiant at maximum lying about a Lyre's length (the distance from Alpha - Vega - to Gamma Lyrae) southwest of Vega at 18h04m RA, +34 degrees Dec, and actually in Hercules, not nearly so close to Vega as some people expect. The extended interval for the peak's timing is based on the most recent detailed analysis of IMO data. The closer it falls to the ~05h UT timing, the higher its Zenithal Hourly Rates (ZHRs) are likely to be, perhaps 20-25 or more. The average ZHR is 18, and tends to be lower the further the maximum happens away from the "ideal" time. In general, the peak is usually quite short, lasting no more than a few hours, but occasionally more prolonged maxima, lasting for 8+ hours have been seen, recently in 2000 and 2001, and rare strong ZHRs of up to 90 (last in 1982 over the USA) may occur too. Thus, when there is little or no Moon, sadly not including this year, the shower is always one to watch. Lyrids are medium-fast meteors, and can be very bright sometimes. Anyone wanting to brave the Moon in the hopes of spotting a few should watch as much sky as is comfortably possible, facing away from the Moon (perhaps best towards Ursa Major-Gemini-Leo). Hopefully, the radio meteor observers will have better luck, though the shower is not always easy to identify from the background rates even so. The last Lyrids fade away around April 25.

Alastair McBeath,
Meteor Director, Society for Popular Astronomy.
E-mail: <meteor@popastro.com> (messages under 150 kB in size only, please)


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PostPosted: Thu Apr 17, 2008 11:56 am 
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Location: Costa Blanca, Spain 37.963N 0.738W
Thanks for the info - will be looking out for them.

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PostPosted: Wed Apr 23, 2008 7:10 pm 
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Sky conditions here in southeast Northumberland weren't at their best overnight on April 21-22, even without the bright Moon hanging low to the south, with broken clouds and streaky haze during the first half of the night. After 23:30 UT, things were marginally better for a time, with less opaque cloud, but a lot more thin cirriform streaks, which, lit up by the Moon, reduced the limiting magnitude to around +5.3 to +5.0 when I first went out to see what was happening, shortly before midnight UT. It was evident immediately that conditions were too poor for formal meteor observing, so I carried out a run of casual sky-checks instead, on and off for about an hour, as the sky gradually deteriorated (by about 01h UT, the limiting magnitude was just +4.6, and there was a lot of thick, hazy cloud by then too). In a total effective observing time of roughly 30 minutes, I spotted a grand total of two sporadics! Not a single Lyrid all night... Given the poor sky, this wasn't especially surprising, but the lack of Lyrids wasn't particularly welcome either.

Last night (April 22-23) had marginally worse conditions, with a lot of fast-moving low cloud, and a limiting magnitude of, at best, +4.8. despite that, I managed to spot a lone probable Lyrid (the radiant was in cloud at the time...) and another sporadic in 15 minutes of sky-checking around 00:15-00:30 UT. It clouded-up finally shortly after, but at least I caught one probable shower meteor. Roll on the Perseids!

Alastair McBeath,
Meteor Director, Society for Popular Astronomy.
E-mail: <meteor@popastro.com> (messages under 150 kB in size only, please)


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PostPosted: Wed Apr 23, 2008 7:15 pm 
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Joined: Wed Nov 28, 2007 2:21 pm
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Location: Hampshire, UK
I kept a look out too, but it was cloudy, so haven't seen a thing... :(

How many nights will it go on for or just til 22nd?


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PostPosted: Thu Apr 24, 2008 7:29 pm 
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Location: Goosnargh, north of Preston, UK
Melanie wrote:
How many nights will it go on for or just til 22nd?


Hi Melanie,

Lyrid activity is decreasing but will continue until around the 25th April, so there's still a chance to see one or two Lyrids after 22:30 UT (23:30 BST) tonight, through to morning twilight.

Good luck.

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PostPosted: Thu Apr 24, 2008 9:35 pm 
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Joined: Wed Nov 28, 2007 2:21 pm
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Location: Hampshire, UK
oh great thanks i'll have a go....


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PostPosted: Fri Apr 25, 2008 3:34 am 
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Location: Fraserburgh, Scotland
Well I was out all night and I saw one. :roll: :wink:

TBH I did have my eye to the scope most of the night, looking in the Leo-Virgo-Coma Bernice area.

However I did see an absolute cracking sporadic. Nice greenish tinge with a pronounced trail. I saw an even better one on Monday night. These two have been the nicest meteors I've seen for a few years.

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PostPosted: Fri Apr 25, 2008 7:37 am 
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Location: Hampshire, UK
oh lucky i wish i could, i went out side but it's so late on a 'school' nite tht i had to go in to bed for work this morning,. :(


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