Results of the IMO Video Meteor Network - May 2008
==================================================
Up to now, May was the month were we had recorded least meteors. Between 1993
and 2007, only 10,002 shooting stars were captured by our video network. That
picture has changed, however, thanks to the exceptional weather this year. In
the first half of May, there were essentially clear skies at each observing
site. We have nine cameras that could observe in 13 or more of the first 15
May nights.
The weather changed rapidly in the second half of the month, when we had the
typical mix of clouds and rain, but overall we recorded more than 3500 meteors
in more than 1500 hours of effective observing time. That's about twice as
many observing hours and two third more meteors as in 2007, the best year so
far. Hence, May has now overtaken June, from which we have 11,680 records in
the video meteor database. It remains to see, how the distribution looks like
after the next month.
With the eta-Aquariids there is a major shower early May, which, however, is
difficult to observe from northern latitudes where most cameras are located.
So it is no surprise that the following minor shower of the eta-Lyrids seemed
to have about the same activity. This impression is supported by an analysis,
where the number of shower meteors is summed up for each night and normalized
by the number of sporadics in the same night. The eta-Aquariids show an
activity profile with a broad maximum between May 4 and May 9 (figure 1). At
maximum their count was about a quarter of the sporadic count. The profile of
the eta-Lyrids has a more compact maximum between May 9 and May 11, where
they also reach about a quarter of the sporadic count.
Figure 1: Activity profiles of the eta-Aquariids, eta-Lyrids, and the
Antihelion source in the first half of May.
Which influence does the observing geometry have? The observability function
(that is the integral over the sine of the radiant altitude in the course of
the night) of the showers for a mean latitude of 48 deg N yields an
observation probability of about 5% for the eta-Aquariids, 31% for the
Antihelion source, and 74% for the eta-Lyrids. That reflects, that the
eta-Aquariids radiant rises only at dawn, whereas the radiant of the
eta-Lyrids in high up in the sky all night long. If we now set the maximum
ZHR of the eta-Aquariids to 50, we get a corrected average ZHR estimates of
the Antihelion source below 20, and a peak eta-Lyrids ZHR estimate of
about 3. That's much closer to the expected values.
1. Observers
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Code Name Place Camera FOV LM Nights Time Meteors
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BENOR Benitez-S. Las Palmas TIMES4 (1.4/50) 20 dg 3 mag 3 1.1 h 5
TIMES5 (0.95/50) 10 dg 3 mag 2 0.3 h 2
BRIBE Brinkmann Herne HERMINE (0.8/6) 55 dg 3 mag 22 106.7 h 162
CASFL Castellani Monte Baldo BMH1 (0.8/6) 55 dg 3 mag 17 52.5 h 102
BMH2 (0.8/6) 55 dg 3 mag 9 24.2 h 35
CRIST Crivello Valbrevenna STG38 (0.8/3.8) 80 dg 3 mag 2 12.9 h 20
ELTMA Eltri Venezia MET38 (0.8/3.8) 80 dg 3 mag 3 20.1 h 61
GONRU Goncalves Tomar TEMPLAR1(0.8/3.8) 80 dg 3 mag 12 62.4 h 72
HERCA Hergenroth. Tucson SALSA (1.2/4) 80 dg 3 mag 22 151.2 h 191
HINWO Hinz Brannenburg AKM2 (0.85/25) 32 dg 6 mag 18 84.4 h 206
KACJA Kac Kostanjevec METKA (0.8/8) 42 dg 4 mag 15 75.5 h 127
Kamnik REZIKA (0.8/6) 55 dg 3 mag 6 36.5 h 98
Ljubljana ORION1 (0.8/8) 42 dg 4 mag 20 82.4 h 124
KOSDE Koschny Noordwijkerh. ICC4 (0.85/25) 25 dg 5 mag 10 40.9 h 83
LUNRO Lunsford Chula Vista BOCAM (1.4/50) 60 dg 6 mag 14 64.7 h 270
MOLSI Molau Seysdorf AVIS2 (1.4/50) 60 dg 6 mag 15 80.8 h 739
MINCAM1 (0.8/6) 55 dg 3 mag 19 103.7 h 162
Ketzuer REMO1 (0.8/3.8) 80 dg 3 mag 21 112.0 h 176
REMO2 (0.8/3.8) 80 dg 3 mag 6 24.6 h 69
PRZDA Przewozny Berlin ARMEFA (0.8/6) 55 dg 3 mag 14 79.1 h 156
SLAST Slavec Ljubljana KAYAK1 (1.8/28) 50 dg 4 mag 14 52.5 h 87
STOEN Stomeo Scorze MIN38 (0.8/3.8) 80 dg 3 mag 11 54.2 h 152
STRJO Strunk Herford MINCAM2 (0.8/6) 55 dg 3 mag 24 60.7 h 89
MINCAM3 (0.8/8) 42 dg 4 mag 17 39.0 h 63
MINCAM5 (0.8/6) 55 dg 3 mag 20 82.7 h 165
WEBMI Weber Chouzava TOMIL (1.4/50) 50 dg 6 mag 4 5.6 h 86
YRJIL Yrjola Kuusankoski FINEXCAM (0.8/6) 55 dg 3 mag 18 52.4 h 62
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Sum 31 1563.5 h 3564
2. Observing Times (h)
======================
May 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15
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BENOR - - 0.1 - - - - - 0.3 - - - - - 0.7
- - 0.2 - - - - - - - - - - - 0.1
BRIBE 2.4 2.5 7.7 1.1 7.6 7.5 7.4 7.4 7.3 7.2 7.2 7.1 2.3 2.0 -
CASFL - 2.0 3.0 - 7.4 - - 2.8 7.2 0.5 6.4 2.4 5.0 4.4 1.3
- 1.0 - - - - - - - - - - 3.3 4.2 3.9
CRIST 5.5 7.4 - - - - - - - - - - - - -
ELTRI - - - - 6.4 - - 7.2 - - - - 6.5 - -
GONRU 8.2 - - 7.7 - 5.3 3.9 7.9 3.7 2.5 - - - - -
HERCA 3.8 8.8 8.7 4.7 8.7 8.6 7.0 5.6 1.6 8.5 7.4 8.5 8.4 8.4 5.0
HINWO 5.3 - 2.7 6.6 1.5 3.9 6.5 6.4 6.3 6.3 6.2 6.1 6.1 4.5 -
KACJA 2.0 5.1 5.5 1.6 - - 4.2 7.4 - - 7.1 7.1 7.0 4.2 2.8
- - - - - - 6.1 4.3 - - 4.9 7.1 7.2 6.9 -
1.1 5.8 0.8 - 1.6 5.3 2.4 6.4 3.2 5.3 7.3 6.3 6.2 5.1 1.3
KOSDE - - - 5.6 5.9 4.3 2.8 5.1 - - - - 2.2 1.0 -
LUNRO 2.3 7.5 8.5 2.0 2.5 - - 3.4 - - - - - - -
MOLSI 6.0 - 5.4 6.5 5.8 - 5.7 6.2 5.5 6.1 4.2 5.9 5.7 5.9 -
5.0 2.6 4.4 2.3 7.2 7.2 7.1 7.1 7.0 6.9 6.9 6.8 6.8 5.2 -
6.8 6.7 6.6 6.6 6.5 6.4 6.3 6.3 6.2 - 6.1 6.0 5.9 5.8 1.7
4.8 2.3 3.6 5.6 - - - - - - - - - - -
PRZDA 2.7 6.8 6.7 - 6.5 6.5 6.4 6.3 6.2 - - - - - -
SLAST - 4.5 1.5 - - 5.4 3.6 3.3 - 2.2 6.6 3.7 2.5 3.0 -
STOEN 6.5 7.3 1.4 - 7.3 - - 4.7 5.4 - 0.9 6.3 6.9 1.4 -
STRJO 2.5 1.3 4.7 4.6 2.0 4.4 4.1 4.0 4.0 4.0 3.5 2.1 3.1 0.5 -
1.5 0.5 1.8 4.2 2.1 2.7 4.3 0.7 5.5 3.8 2.0 2.0 1.6 - -
4.0 5.8 4.3 4.1 6.0 6.0 5.9 5.8 5.7 5.2 5.5 4.3 2.6 - -
WEBMI - - - - 1.4 1.4 1.4 1.4 - - - - - - -
YRJIL - 3.8 3.7 3.3 3.7 - 3.0 - 2.5 2.6 2.6 3.3 - 2.4 3.2
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Sum 70.4 81.7 81.3 66.5 90.1 74.9 88.1109.7 77.6 61.1 84.8 85.0 89.3 64.9 20.0
May 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
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BENOR - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - -
BRIBE 0.3 - 1.0 6.7 6.8 6.6 1.8 6.5 - - - - 0.3 - - -
CASFL - - 0.7 - - - - - - - 4.4 1.5 1.7 0.5 - 1.3
2.8 - - - - - - - - 1.4 2.4 - 1.0 - - 4.2
CRIST - - - - - - - - - - - - - - - -
ELTRI - - - - - - - - - - - - - - - -
GONRU 6.3 4.4 - - - 2.6 - 2.5 - - - - - - 7.4 -
HERCA 7.0 8.2 8.0 8.3 8.2 4.2 3.6 - - - - - - - - -
HINWO - - - - - - - 5.5 1.5 - 5.2 1.1 - 3.1 - -
KACJA - - - - - - - - 6.7 - - 6.1 - 2.2 - 6.5
- - - - - - - - - - - - - - - -
- - - - - - - - - 4.7 5.5 4.6 - 4.5 3.6 1.4
KOSDE - - - - 5.8 5.5 - 2.7 - - - - - - - -
LUNRO 2.0 7.5 4.8 7.5 1.7 - - - - - - - 3.1 4.7 7.2 -
MOLSI - - - - - - - - - 2.4 - - - 4.7 4.8 -
- - - - - - - 6.2 - - 2.1 - - 6.0 6.0 0.9
1.1 - 2.5 3.4 5.4 5.4 - 5.2 5.1 - - - - - - -
- - - - - - - 3.2 5.1 - - - - - - -
PRZDA - - - 5.5 - 5.4 - - 5.2 5.2 - - - - 4.9 4.8
SLAST - - - - - - - - - - 3.5 3.1 - - 4.1 5.5
STOEN - - - - - - - - - - - 6.1 - - - -
STRJO 0.5 - 1.5 3.0 2.4 0.9 2.7 2.7 0.7 - - - 0.5 1.0 - -
- - - 2.1 - - 1.5 1.5 1.2 - - - - - - -
- - 1.3 4.9 0.8 3.8 3.0 3.2 0.5 - - - - - - -
WEBMI - - - - - - - - - - - - - - - -
YRJIL 2.9 - - - 2.4 - 2.5 2.6 2.9 2.8 - - - - 2.2 -
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Sum 22.9 20.1 19.8 41.4 33.5 34.4 15.1 41.8 28.9 16.5 23.1 22.5 6.6 26.7 40.2 24.6
3. Results (Meteors)
====================
May 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15
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BENOR - - 1 - - - - - 2 - - - - - 2
- - 1 - - - - - - - - - - - 1
BRIBE 5 8 13 4 10 12 8 16 12 10 6 7 4 3 -
CASFL - 8 1 - 7 - - 9 10 1 11 5 18 10 3
- 2 - - - - - - - - - - 4 7 6
CRIST 9 11 - - - - - - - - - - - - -
ELTRI - - - - 26 - - 20 - - - - 15 - -
GONRU 9 - - 9 - 5 2 11 5 1 - - - - -
HERCA 6 11 11 8 15 9 9 7 4 10 8 11 6 10 8
HINWO 6 - 11 10 1 13 13 21 20 15 24 23 15 8 -
KACJA 5 13 7 2 - - 10 17 - - 14 9 13 4 2
- - - - - - 17 18 - - 18 16 16 13 -
1 11 2 - 2 11 3 9 7 12 9 12 12 4 1
KOSDE - - - 12 10 7 4 19 - - - - 4 2 -
LUNRO 7 16 23 22 27 - - 69 - - - - - - -
MOLSI 53 - 46 71 49 - 60 73 64 70 51 48 51 31 -
8 3 5 8 11 16 10 10 17 11 7 12 8 5 -
6 5 12 6 5 11 7 16 21 - 11 6 8 9 3
15 5 17 15 - - - - - - - - - - -
PRZDA 8 7 10 - 9 9 5 23 16 - - - - - -
SLAST - 11 2 - - 12 7 7 - 2 8 10 4 4 -
STOEN 16 17 1 - 22 - - 19 17 - 2 22 19 2 -
STRJO 4 3 6 6 3 6 5 4 6 5 4 2 7 1 -
3 1 3 8 4 4 8 1 7 4 2 4 3 - -
8 13 7 10 15 14 9 12 10 18 1 10 5 - -
WEBMI - - - - 23 19 28 16 - - - - - - -
YRJIL - 6 1 7 7 - 2 - 1 8 1 7 - 1 3
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Sum 169 151 180 198 246 148 207 397 219 167 177 204 212 114 29
May 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
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BENOR - - - - - - - - - - - - - - - -
- - - - - - - - - - - - - - - -
BRIBE 1 - 3 7 13 6 3 10 - - - - 1 - - -
CASFL - - 1 - - - - - - - 9 2 3 1 - 3
1 - - - - - - - - 2 5 - 3 - - 5
CRIST - - - - - - - - - - - - - - - -
ELTRI - - - - - - - - - - - - - - - -
GONRU 8 8 - - - 1 - 3 - - - - - - 10 -
HERCA 9 12 8 11 9 5 4 - - - - - - - - -
HINWO - - - - - - - 11 4 - 7 1 - 3 - -
KACJA - - - - - - - - 11 - - 8 - 2 - 10
- - - - - - - - - - - - - - - -
- - - - - - - - - 4 6 6 - 5 5 2
KOSDE - - - - 12 9 - 4 - - - - - - - -
LUNRO 4 26 19 14 2 - - - - - - - 11 10 20 -
MOLSI - - - - - - - - - 8 - - - 30 34 -
- - - - - - - 11 - - 1 - - 9 7 3
3 - 4 4 11 10 - 7 11 - - - - - - -
- - - - - - - 5 12 - - - - - - -
PRZDA - - - 10 - 10 - - 14 14 - - - - 6 15
SLAST - - - - - - - - - - 5 6 - - 6 3
STOEN - - - - - - - - - - - 15 - - - -
STRJO 1 - 3 5 4 1 4 4 2 - - - 1 2 - -
- - - 4 - - 3 2 2 - - - - - - -
- - 3 7 3 6 6 7 1 - - - - - - -
WEBMI - - - - - - - - - - - - - - - -
YRJIL 10 - - - 1 - 1 3 1 1 - - - - 1 -
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Sum 37 46 41 62 55 48 21 67 58 29 33 38 19 62 89 41
Sirko Molau, 2008/06/20