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 Post subject: Perseids 2008
PostPosted: Sat Aug 02, 2008 7:47 am 
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The Perseid maximum is due between 11h30m-14h00m UT on August 12 this year, and should produce typical healthy Perseid numbers. Zenithal Hourly Rates (ZHRs) thus should be around 80-100. Though this timing is obviously poor for British visual observers, the peak should still remain observable by radio methods even here (as long as interference permits, at least). However, Finnish meteor expert Esko Lyytinen has suggested the Earth may encounter a denser meteoroid trail for perhaps an hour or so centred on 05h26m UT that morning, producing an additional stronger maximum ahead of what would be usually the main peak, much as was seen back in 1991-98 and again in 2004. Esko suggested ZHRs could reach 100-300, perhaps higher, and there seems a good prospect for brighter than normal Perseid meteors to be involved. This timing too is unhelpful for British visual observers of course, but we should catch part of the rising activity this way later in the night of August 11-12, with luck, and again radio observers should be able to cover this potential peak interval from here. Meteor rates will likely remain most acceptable by August 12-13 too, if doubtless below their best. The Moon is waxing gibbous, near its lowest in the sky, and will set around midnight UT for most UK sites on each night, leaving much of the second half of the night free for dark-sky watching. This is so as the shower's radiant first reaches a useful elevation to the northeast by about 22h UT, and improves all night after then, to culminate well after sunrise, around 06h. Perseids are swift, often bright, and commonly trained meteors. The shower lasts from July 17 to August 24 in most years, producing very much lower rates away from the peak.

For more information and a Perseid radiant chart, see the August activity webpage at: http://www.popastro.com/sections/meteor ... ug2008.htm .

If you're able to observe during the Perseids and would like to contribute full information to the SPA Meteor Section, there is advice on how to do so and an electronic report form available via links on the homepage at: http://www.popastro.com/sections/meteor.htm . If you're planning a less formal observing session or two during the shower, that information can still be useful, providing you send me the following data:

1) Your name and observing site (place name and county name for UK locations; place name and geographic coordinates for anywhere else).

2) The date of your watch (ALWAYS use the double-date over midnight to avoid any ambiguity) and the times you watched between, stating clearly if this was in clock time, BST, or GMT/UT. If you took breaks when you were not constantly watching the sky for meteors, please state the total time you WERE watching the sky this way.

3) Give an idea of the sky clarity by noting the magnitude of the faintest star you could just see with averted vision in the general area of sky you were facing. This MUST be estimated using exactly the same degree of concentration as when watching for meteors; do not strain to see a star just a little bit fainter! If this changed notably over time (by more than 0.2 to 0.3 magnitudes), keep a check on how that altered at about 20-minute intervals. If clouds were present, note the percentage of your observing view the clouds covered at similar intervals (so if the sky is clearer elsewhere, turn to face that way instead).

4) Give a count of how many Perseid meteors and how many non-Perseid meteors you saw. Perseids will be moving swifter than many of the other meteors you are likely to see in mid August, providing their paths are longer than roughly 10 degrees. Perseids will be moving away from their radiant, a few degrees northeast of Eta Perseii at the maximum, but can appear in ANY part of the sky. Their paths will tend to be longer the further from the radiant they are (and very short close to the radiant - so don't look here all the time, because short-pathed meteors are much harder to spot). To tell if the meteor may have come from the Perseid radiant, trace the path back across the sky from where it happened in a dead straight line. You can use a rigid straight-edge like a ruler or broom-handle to help with this.

For best results, make sure you'll be warm and comfortable while observing, and watch as much clear sky as practical within those constraints, ideally centring your vision about 20-40 degrees from the Perseid radiant, and at least 30-40 degrees above the horizon. Don't look fixedly in only one direction, but make any head movements slowly and steadily, so as not to miss meteors.

Good luck, and clear skies!

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: Mon Aug 04, 2008 3:54 pm 
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Location: Brockmoor, nr Dudley
Seems to have been a reasonable number of clear(ish) nights lately, and I have to say, whilst out observing I have noticed the slow but steady increase in Perseid activity...

All we need now is clear skies this time next week and hopefully we should get a half decent show :)

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PostPosted: Tue Aug 05, 2008 9:41 am 
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Location: south wales.U.K.
hi all,lets hope for decent conditions this year.down here we have just got access to a nice dark site,looking forward to it.
rgds,andy

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PostPosted: Tue Aug 05, 2008 10:06 am 
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Location: Bruges (just over Channel)
:P A free working day is yet confirmed, I'm looking forward for the night August 11-12 in own garden. Radiant is much higher in the morning hours, and the moon sets at 12 pm. I think not to look earlier. They can be followed until morning twilight at 4h30 am.

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PostPosted: Sat Aug 09, 2008 11:02 am 
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After a frustrating start to August here in south Northumberland, with a few partly clear nights failing to develop into a sky sufficiently usable for meteor watching (not to mention all the cloudy ones, and the near-incessant deluge of rain), I finally found one that cleared after midnight UT last night (August 8-9). Perseid numbers were quite healthy, averaging about one every four minutes over a two-hour spell that started at 00:30 UT, under a mean limiting magnitude - LM - +6.1 sky (the LM variable at times between +6.3 and +5.9, thanks to some occasional thin, hazy cloud). Sporadic rates averaged seven an hour, and with a few minor shower meteors too, rates were pleasantly above 20 an hour from all sources. Nothing too spectacular in what I saw, just one minor, yellow, Perseid fireball of magnitude -3, at 02:19 UT, slipping down below the Plough's "Handle" to my northwest, leaving a 4-second train.

ZHRs from my data alone were about 25. While that figure awaits confirmation from elsewhere, it's about what I'd expect at this stage during a typical Perseid return. You can see roughly what the Perseids are up to globally by visiting the "live" Perseid page on the International Meteor Organization's website, at: http://www.imo.net .

Good luck for your own observing, and still hoping for better skies generally!

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: Mon Aug 11, 2008 6:51 am 
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Location: Bruges (just over Channel)
hello,

Because it can be a disaster of clouds the following night, I already tried to see a few perseids in 1 hour previous night. Since a higher radiant always is better, I started around 1h15 UT.

:shock: I wast just settled, and I saw a bright flash of magnitude 0 in Ursa Minor. Some 20 seconds later again a flash a little further. There was no third flash. Only a last flash appeared almost two minutes later next to Deneb. First it looked strange, but yes this only was a big flashing satellite.

Anyway, there appeared 14 meteors in that hour, 9 perseids and 5 sporadics. But it was clear the big firework of the perseids is still to come. Only a bright perseid of mag -1 was seen low above the west at 1h24 UT.

Hopefully the following night also has some clear moments! 8)

gr,

david.

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 Post subject:
PostPosted: Mon Aug 11, 2008 9:40 am 
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Location: Ulverston, Cumbria
Read the article in the link below if you fancy a laugh......

http://www.littlehamptongazette.co.uk/4 ... 4373195.jp


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 Post subject:
PostPosted: Mon Aug 11, 2008 9:47 am 
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Location: 55° 57'N: 03° 08'W
Last week he was doing the horoscopes, next week it's Births, Marriages and deaths.


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PostPosted: Mon Aug 11, 2008 11:05 am 
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Mogget wrote:
Read the article in the link


I sent an email to them yesterday morning with the correct details.

It looks like they ignored it.


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 Post subject:
PostPosted: Mon Aug 11, 2008 11:45 am 
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Location: 55° 57'N: 03° 08'W
"I was just settled, and I saw a bright flash of magnitude 0 in Ursa Minor. Some 20 seconds later again a flash a little further. There was no third flash. Only a last flash appeared almost two minutes later next to Deneb. First it looked strange, but yes this only was a big flashing satellite."

This seems to be Iridium 69, 98-26A (#25319) which passed through
both Ursa Minor and Cygnus.

The track can be confirmed using the Heavens-Above website.


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 Post subject:
PostPosted: Tue Aug 12, 2008 12:15 am 
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Managed to catch a handful of Perseids and a few sporadics before the clouds crept in.
A lower rate than i was expecting but a nice night observing for me.


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PostPosted: Tue Aug 12, 2008 4:41 pm 
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Joined: Sun Aug 13, 2006 12:29 pm
Posts: 663
Location: Goosnargh, north of Preston, UK
I was please to see the work of New Mexico, amateur astronomer and fellow radio meteor observer, Thomas Ashcraft, featured on SpaceWeather.com.

The nights of 2008 08 10-11, 11-12 and 12-13 have all been cloudy here in Lancashire, so no visual Perseids to report.

My own preliminary radio meteor results are attached below - I'll update the comments as time passes.

The preliminary comments are based on a quick look at the raw counts of my own radio meteor system. A clearer picture will be obtained when all observer's results are collected and analyzed in full.

The first chart shows the meteor counts in intervals of one hour, over a seven day period. The raw counts suggest Perseid activity building to a early peak from the late evening of the 11th August through the morning of the 12th August. The counts indicate that activity remained high at least until 13:00 UT on the 12th August. The recorded counts then fell, as expected, as the radiant became lower in the sky. Counts again increase as the radiant gets higher during the late evening of the 12th and the very early morning of the 13th August. Particularly high counts were recorded during the interval 2008 08 13 01:00 - 03:00 UT possibly suggesting a peak of activity later than expected. This view may be modified when additional data is recorded and the consequence of the radiant position is taken into account during a full analysis of the data.

Image

The second chart shows the total echo-duration the earlier peak, recorded in intervals of ten minutes, over a one day period. The total echo-duration for 12th August shows an early peak in the interval 2008 08 12 05:20 UT - 05:30 UT, which corresponds well with the prediction of enhanced activity from Esko Lyytinen (2008 08 12 05:26 UT See Alastair's original post for details).

Image

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Last edited by david entwistle on Thu Aug 14, 2008 8:22 am, edited 10 times in total.

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 Post subject:
PostPosted: Tue Aug 12, 2008 7:59 pm 
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Location: Manchester
Dear David
Very nice ones, brilliant stuff !
Best of luck from Cliff
PS Cloudy last night here, raining now although the forecasters say may be clear skies in the early hours, unfortunately I wont be still active myself then.


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PostPosted: Wed Aug 13, 2008 6:34 am 
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Location: Camberley, Surrey
This morning between 02:00 - 03:00 I was fortunate enough to have clear skies and observed 33 perseids over that time period. Only 3 of these were noteworthy, the rest being very short and dim.

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PostPosted: Wed Aug 13, 2008 12:20 pm 
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Joined: Tue Nov 21, 2006 2:04 pm
Posts: 55
Location: St.agnes, Cornwall
Wow I've not been here in a while but after viewing some beautiful skies last night I thought I'd come and say a little hi and let you all know what we saw.

Between 10pm and 1am we had beautiful skies here, the moon had settled and been lost behind our house in the earlier part of our session, so we had no issues there this year. Between 10 and 11pm, we averaged at seeing around the 60 mark with this increasing to 75ish between 12 and 1am. Quite something to see! Some were noticeably different to the others, rather slow and larger, very bright and very pretty. Enough time to point it out to my partner, who then had time to view it for a split second. The cloud came over though and settled in and I finally gave up waiting for another break in the clouds and hit the sack at 3:30.

Brilliant night considering not everyone had the break in the clouds that we got!


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