(meteorobs) Video Observation Results - November 2008

Sirko Molau sirko at molau.de
Tue Dec 23 17:27:45 EST 2008


Results of the IMO Video Meteor Network - November 2008
=======================================================

For most European observers, November was a typical cloudy fall month
presenting only a few clear nights. Our two American observers, on the other
hand, enjoyed once more perfect conditions and collected more than 25
observing nights. Also in Portugal and parts of Italy, the weather was fine.
Our new observers Paolo Ochner and Fabio Moschini, for example, who jointly
operate a meteor camera in Albiano near the city of Trento, managed to
collected more than 100 hours of effective observing time right at the start.
As also Stefano Crivello is now operating a second camera, we have seven
cameras in operation in Italy. The number of observers is identical to
Germany (5). In Slovenia, Javor Kac is operating a fourth camera. Overall,
we collected more than 2,200 hours of effective observing time despite the
weather, which is the third best result in the IMO network. With more than
9,000 meteors, November 2008 can of course not keep up wit August or October,
but it still was the best November result to date.

No other meteor shower has spured on meteor science in the last decade as
much as the Leonids. Meanwhile, the dust trail model has been successfully
applied to predict outbursts of different meteor showers. This year, however,
it was once more the Leonids that proved the strength of the model, which
celebrated its first major success during the Leonid storm of 1999.
On November 17, 2008, at 01:30 UT (i.e. more than a decade after the last
return of the parent comet) Earth was supposed to cross the 1466 dust trail.
Therefor, Jeremie Vaubaillon predicted enhanced activity with a ZHR between
25 and 100. Visual observations were rare, because weather permitted meteor
observations almost nowhere in Europe, and the waning moon did the rest.
Still, the live activity profile of IMO confirmed a peak ZHR of nearly 100
between 01:45 and 02:30 UT.

Unfortunately, video observers were hampered similarly by the poor sky. Just
a single camera in Portugal (TEMPLAR1) enjoyed clear skies all night long,
but the moon crossed the field of view just at the maximum, so that only 39
Leonids were recorded in total. Other observers catched at least a part of
the outburst. In Berlin, ARMEFA recorded 8 Leonids between 01:30 and 02:00 UT.
BMH2 observed a total of 16 Leonids in northern Italy between 01:40 and
03:00 UT (but clouds drifted through the field of view all night long). North
of Munich, skies cleared after a shower front at 02:10 UT. Until the end of
night at 05:30 UT, MINCAM1 could record 67 Leonids under good conditions.
In Genua the clouds disappeared completely at 04:00 UT only. Until 05:30 UT,
C3P8 still recorded 37 Leonids, and STG38 11 Leonids.

The figure http://www.imonet.org/reports/20081101.gif shows the hourly
Leonid rate of MINCAM1 and TEMPLAR1, corrected for the radiant altitude.
In addition, an empirical correction factor was applied for TEMPLAR1 to
account for the percentage of the field of view glared by the moon.
These data sets can only give a rough hint on the Leonid activity, but
they suggest that the outburst might have lasted longer than derived from
the sparse visual data. Between 01:30 and 05:30 UT, the Leonid rate was
enhanced, with a maximum between 02:00 and 03:30 UT.

What else did we learn about the Leonids from the data of the IMO network?
Accoring to the last edition of the IMO handbook for meteor observers, this
shower is active between November 10 and 23. In the recent analysis of the
video data, almost 25,000 Leonids could be identified between November 7
and 28. Thus, this shower even outperforms the Perseids thanks to numerous
video observations during the major storms of 1999 to 2002. The radiant is
well defined all the time (http://www.imonet.org/reports/20081102.gif),
from which we can conclude that the extended activity interval is real. The
radiant is found about a degree north of the position given in the IMO
handbook.

Between solar longitude 235 and 237, the long-term activity profile of the
Leonids (http://www.imonet.org/reports/20081103.gif) is shaped by the
different meteor storms of the last decade. More reliable are the values
away from the maximum, which confirm a roughly symmetric activity profile.

Right after the Leonids, the alpha Monocerotids become active, whereby
"active" is a relative term. If we do not witness one of the rare outbursts
as in 1995, the shower is hardly noticeable. In the latest meteor shower
analysis, the alpha Monocerotids were not detected at all, and also the
list of individual radiants per solar longitude interval shows no sign of
this shower.
Instead of that, the "other" Monocerotids are present twice in the list!
According to the IMO handbook, the Monocerotids are active between November 27
and December 17. Indeed, a shower with 630 meteors was found in the video
data, whose radiant position and drift matched perfectly to the values given
in the handbook (http://www.imonet.org/reports/20081104.gif, red). Also the
velocity (41 km/s) is in agreement with the literature (42 km/s).
The second shower in the video data was found with 850 meteors between
November 18 and December 9 (or December 7, if only  times with a well-defined
radiant are taken into consideration). Thus, the activity interval slightly
overlaps with the "classical" Monocerotids. The radiant  of the second
shower (http://www.imonet.org/reports/20081104.gif, green) lies about
7 degrees north of the Monocerotids, and both the amount and the direction
of the radiant drift are identical. Yet, with 46 km/s velocity at infinity,
the second shower is slightly faster than the Monocerotids.

The "classical" Monocerotids reach their peak activity right at the beginning
on December 7/8 (IMO handbook: December 8), and the second shower peaks at
the end of November. The peak activity level of both showers is identical.
Interestingly, also the activity profile given in the IMO handbook (blue dots)
shows not just a single maximum, but enhanced rates in early December
(http://www.imonet.org/reports/20081105.gif). It suggests, that the visual
profile covers the activity of both showers, which is no surprise given a
peak ZHR of 2 and a radiant distance of seven degrees only. That would also
explain, why according to the IMO handbook the activity of the Monocerotids
starts earlier than was found in the video data.

To verify the result, a few radiant plots were computed with the Radiant
software. The two examples at http://www.imonet.org/reports/20081106.gif
(solar longitude 253-255 and 258-260 degree, vinf=42 km/s) prove, that
there are indeed two distinct radiants. Whereas in the first plot the
northern component dominates, it is the southern component in the second
plot. We see, that the second shower is active beyond the activity
interval found by the automated shower analysis. It confirms, that the
statistical meteor shower search is limited when it comes to such close
radiants with similar velocity.

It leads us to the last question: Are these two branches of the same shower
(similar to the northern and southern Taurids) or do we observe two
independent showers? The similarity of both is an argument for a single
shower; the small, but significant difference in velocity is a counter
argument. For this reason, I tend to believe in two independent meteor
showers.

In the end, let's have a retrospect at the Taurids: Their brightness
distribution at the end of October seemed to suggest, that the Taurids of
2008 were brighter than in the years before. If the plot is extended until
November 20 with the newly available data
(http://www.imonet.org/reports/20081107.gif), this result is not
confirmed. There are indeed times where the shower meteors are somewhat
brighter than usual, but at other times they are equally fainter. Overall
there is no clear trend towards brighter Taurids in 2008.


1. Observers
============

Code    Name        Place           Camera         FOV    LM Nights Time Meteors
--------------------------------------------------------------------------------
BENOR Benitez-S.  Las-Palmas    TIMES5 (0.95/50)  10 dg  3 mag 14   43.4 h    89
BRIBE Brinkmann   Herne         HERMINE (0.8/6)   55 dg  3 mag  5   17.9 h    94
CASFL Castellani  Monte Baldo   BMH1 (0.8/6)      55 dg  3 mag 15  118.3 h   354
                                BMH2 (0.8/6)      55 dg  3 mag 22  147.4 h   478
CRIST Crivello    Valbrevenna   STG38 (0.8/3.8)   80 dg  3 mag  2   20.8 h   111
                  Genova        C3P8 (0.8/3.8)    80 dg  3 mag 14  101.3 h   581
ELTMA Eltri       Venezia       MET38 (0.8/3.8)   80 dg  3 mag  6   52.6 h   207
GONRU Goncalves   Tomar         TEMPLAR1 (0.8/6)  55 dg  3 mag 22  183.1 h  1036
HERCA Hergenroth. Tucson        SALSA (1.2/4)     80 dg  3 mag 28  258.5 h   596
HINWO Hinz        Brannenburg   AKM2 (0.85/25)    32 dg  6 mag 17  108.0 h   489
KACJA Kac         Kostanjevec   METKA (0.8/8)     42 dg  4 mag 14  110.6 h   303
                  Kamnik        REZIKA (0.8/6)    55 dg  3 mag 13   79.4 h   404
                                STEFKA (0.8/3.8)  80 dg  3 mag  6   31.8 h    82
                  Ljubljana     ORION1 (0.8/8)    42 dg  4 mag 13   65.6 h   180
KOSDE Koschny     Noordwijkerh. TEC1 (1.4/12)     30 dg  4 mag  3   7.4 h    21
LUNRO Lunsford    Chula Vista   BOCAM (1.4/50)    60 dg  6 mag 26  221.2 h  1368
MOLSI Molau       Seysdorf      AVIS2 (1.4/50)    60 dg  6 mag 15   71.3 h   661
                                MINCAM1 (0.8/6)   55 dg  3 mag 22   79.7 h   221
                  Ketzuer       REMO1 (0.8/3.8)   80 dg  3 mag  4   13.5 h    35
                                REMO2 (0.8/3.8)   80 dg  3 mag  4   12.7 h    35
OCHPA Ochner      Albiano       ALBIANO (1.2/4.5) 68 dg  3 mag 15  112.3 h   418
PRZDA Przewozny   Berlin        ARMEFA (0.8/6)    55 dg  3 mag 12   67.9 h   219
SLAST Slavec      Ljubljana     KAYAK1 (1.8/28)   50 dg  4 mag 11   58.0 h   134
STOEN Stomeo      Scorze        MIN38 (0.8/3.8)   80 dg  3 mag 15   92.8 h   320
STRJO Strunk      Herford       MINCAM2 (0.8/6)   55 dg  3 mag  9   44.9 h   153
                                MINCAM3 (0.8/8)   42 dg  4 mag  8   28.7 h    88
                                MINCAM5 (0.8/6)   55 dg  3 mag  9   40.3 h   223
YRJIL Yrjola      Kuusankoski   FINEXCAM (0.8/6)  55 dg  3 mag 17   73.7 h   270
--------------------------------------------------------------------------------
Overall                                                        30 2263.1 h  9170


2. Observing Times (h)
======================

Nov    01   02   03   04   05   06   07   08   09   10   11   12   13   14   15
--------------------------------------------------------------------------------
BENOR   -   2.9  5.6   -   1.0   -   3.0   -   7.2  1.0  5.5  1.0   -    -   2.0
BRIBE   -    -   8.4   -    -    -   3.3  5.3   -    -    -   0.6   -    -    -
CASFL  9.3  5.1   -    -    -    -    -    -    -    -    -    -    -    -   9.3
       9.3  2.6  1.2  0.5  1.0   -    -   2.7 11.7 11.7   -    -    -  11.8  9.3
CRIST   -    -    -    -    -    -    -    -    -    -    -    -    -    -  11.1
       1.1   -   5.0   -    -    -   8.9  5.4   -    -    -    -    -    -  10.3
ELTMA   -    -    -    -    -    -    -    -    -    -    -    -    -  12.0 12.2
GONRU  5.2  1.8   -    -   8.4   -   6.3 10.5 10.1   -    -   5.1  3.1  5.8  9.5
HERCA 11.5 11.4 11.5 11.5 11.5 11.6 11.6 11.6 11.7  4.0  7.2  7.5  2.0 11.6 11.6
HINWO 10.8  1.0  5.3   -  11.9   -    -   9.1  6.5 10.9   -    -    -    -  12.1
KACJA 11.7   -   4.6   -    -    -    -    -    -    -   6.2   -    -    -  11.1
        -   9.0 10.0   -   1.5   -   0.9 10.4   -    -    -   5.1  2.8  1.8 10.1
        -    -    -    -    -    -    -    -    -    -    -    -    -    -    -
        -   4.2  5.4   -    -    -    -   2.4  1.7   -   1.1   -    -    -   4.0
KOSDE  0.5   -    -    -    -   2.7  4.2   -    -    -    -    -    -    -    -
LUNRO 10.8  5.7  4.2  2.5  7.3 11.4 11.4 11.3  5.7  6.1  7.2  8.4 11.4 11.6 11.5
MOLSI  9.7   -   2.4   -   6.6   -    -    -   3.1  9.7   -    -    -    -   7.0
       3.9   -   6.0   -   6.6   -   1.3  1.7  2.1  7.8   -    -    -   3.0  7.5
       4.5   -    -   0.2   -    -   2.0  6.8   -    -    -    -    -    -    -
       8.0   -    -   0.3   -    -   1.1  3.3   -    -    -    -    -    -    -
OCHPA   -    -    -    -    -    -    -   2.0  8.4  9.8   -    -    -   3.8 10.2
PRZDA  3.3   -    -    -    -    -    -   4.0  2.0  7.6 10.6   -   6.6   -    -
SLAST  3.8  6.7  5.8   -    -    -    -    -    -    -    -    -    -    -   2.3
STOEN 10.0   -    -    -   5.2  1.0   -   1.3   -    -    -    -    -  12.4 12.4
STRJO  0.2  0.5  4.5   -    -    -   7.5  6.0  2.0  0.5  5.3   -   1.2   -    -
        -    -    -    -    -    -   3.9  8.7  1.9   -   4.5   -   0.8   -    -
        -    -    -    -    -    -   5.0  8.6  2.2   -   5.0   -   1.0   -    -
YRJIL  7.3  3.8  2.8  8.0  4.8  7.9   -    -    -    -    -   1.2   -   1.9   -
--------------------------------------------------------------------------------
Sum  120.9 54.7 82.7 23.0 65.8 34.6 70.4111.1 76.3 69.1 52.6 28.9 28.9 75.7163.5

Nov    16   17   18   19   20   21   22   23   24   25   26   27   28   29   30
--------------------------------------------------------------------------------
BENOR  6.3  2.8  2.8   -   0.3  2.0   -    -    -    -    -    -    -    -    -
BRIBE   -    -   0.3   -    -    -    -    -    -    -    -    -    -    -    -
CASFL  2.8  3.4 10.4 10.4 10.4  3.6 10.9  3.5  9.2 12.5 12.5  5.0   -    -    -
       5.5  2.5 11.9  8.9  5.9  4.4  8.4  2.5  9.0 12.0 11.1  3.5   -    -    -
CRIST  9.7   -    -    -    -    -    -    -    -    -    -    -    -    -    -
       8.4  3.9  7.8  5.7   -  11.5  8.4   -   3.0 12.1  9.8   -    -    -    -
ELTMA  8.1   -   6.4   -    -    -  10.3  3.6   -    -    -    -    -    -    -
GONRU 12.1  6.7 12.1 11.8  9.5 12.3 12.2  5.5  7.0 12.3 12.2  3.6   -    -    -
HERCA 11.8 11.6 11.2   -  11.3 11.9 11.9 10.5 11.5  2.0  6.0   -   1.5  6.2  3.3
HINWO   -   5.2  3.3  1.0   -    -    -   1.7   -   6.4  9.2 10.5  0.4  2.7   -
KACJA   -  10.3  5.2  4.8  4.4   -  11.7  6.8   -    -   9.7 12.9   -   5.9  5.3
       7.3   -    -  12.9  7.2   -    -   0.4   -    -    -    -    -    -    -
       1.0  1.9  8.2  1.3   -    -  12.1  7.3   -    -    -    -    -    -    -
        -  10.0  4.9  7.2   -   7.4 12.4  4.5   -    -   0.4   -    -    -    -
KOSDE   -    -    -    -    -    -    -    -    -    -    -    -    -    -    -
LUNRO  8.2 11.5 11.6  8.5 11.6  9.3  8.4  0.5 11.8   -    -    -    -  10.0  3.3
MOLSI   -   3.1  0.4  2.8   -    -    -    -   1.2   -   4.6 11.1  3.2  5.7  0.7
       3.8  6.1  0.1  1.2   -   1.0   -   0.5  0.2  0.7  6.9 11.4  5.0  1.4  1.5
        -    -    -    -    -    -    -    -    -    -    -    -    -    -    -
        -    -    -    -    -    -    -    -    -    -    -    -    -    -    -
OCHPA   -   5.2 11.7  7.5 10.7  4.1   -   5.2  6.6  9.3 12.5  5.3   -    -    -
PRZDA  5.8  8.7   -    -   4.2   -   5.9   -    -   4.7   -    -    -   4.5   -
SLAST   -   4.7  3.7  6.3   -   5.4 11.6  5.7   -    -   2.0   -    -    -    -
STOEN  4.6   -   2.1  5.7   -    -   6.1  2.6  2.4  8.7 10.3  8.0   -    -    -
STRJO  2.2   -   1.5   -   1.0  0.5   -    -    -   0.5   -    -    -   6.6  4.9
       2.7   -    -    -    -    -    -    -    -   0.7   -    -    -   5.5   -
       4.6   -    -    -    -    -    -    -    -   1.0   -    -    -   7.5  5.4
YRJIL   -  13.0   -   3.1  5.7  6.3   -   0.1   -    -   5.6   -   2.2   -    -
--------------------------------------------------------------------------------
Sum  104.9110.6115.6 99.1 82.2 79.7130.3 60.9 61.9 82.9112.8 71.3 12.3 56.0 24.4


3. Results (Meteors)
====================

Nov    01   02   03   04   05   06   07   08   09   10   11   12   13   14   15
--------------------------------------------------------------------------------
BENOR   -    6   13    -    1    -    4    -   10    1    9    1    -    -    6
BRIBE   -    -   50    -    -    -   12   29    -    -    -    2    -    -    -
CASFL  45   10    -    -    -    -    -    -    -    -    -    -    -    -   33
       41    9    7    4    2    -    -    8   32   45    -    -    -   41   38
CRIST   -    -    -    -    -    -    -    -    -    -    -    -    -    -   50
        6    -   15    -    -    -   56   20    -    -    -    -    -    -   54
ELTMA   -    -    -    -    -    -    -    -    -    -    -    -    -   43   53
GONRU  15    2    -    -   40    -   31   73   64    -    -   18    4   13   43
HERCA  28   31   20   26   25   29   27   26   21    8   10   24    3   24   28
HINWO  44    1   11    -   78    -    -   57   48   48    -    -    -    -   44
KACJA  44    -    5    -    -    -    -    -    -    -   10    -    -    -   46
        -   28   36    -    2    -    2   44    -    -    -   68    4   25   55
        -    -    -    -    -    -    -    -    -    -    -    -    -    -    -
        -    8    8    -    -    -    -    3    6    -    2    -    -    -    7
KOSDE   4    -    -    -    -    5   12    -    -    -    -    -    -    -    -
LUNRO  87   21   21   19   35   95  108   84   11   30   51   41   43   70   70
MOLSI  80    -   20    -   51    -    -    -   18   64    -    -    -    -   27
        7    -    6    -    9    -    2    5    5   15    -    -    -    5   10
       16    -    -    1    -    -    6   12    -    -    -    -    -    -    -
       20    -    -    1    -    -    4   10    -    -    -    -    -    -    -
OCHPA   -    -    -    -    -    -    -    2   41   50    -    -    -   10   42
PRZDA   8    -    -    -    -    -    -    7    7   38   16    -   18    -    -
SLAST   8   12   13    -    -    -    -    -    -    -    -    -    -    -    3
STOEN  36    -    -    -   16    4    -    2    -    -    -    -    -   45   63
STRJO   1    1   11    -    -    -   22   16    5    1   25    -    3    -    -
        -    -    -    -    -    -    8   23    7    -   18    -    1    -    -
        -    -    -    -    -    -   43   47    5    -   32    -    2    -    -
YRJIL  19   14    9   32   22   36    -    -    -    -    -    3    -    3    -
--------------------------------------------------------------------------------
Sum   509  143  245   83  281  169  337  468  280  300  173  157   78  279  672

Nov    16   17   18   19   20   21   22   23   24   25   26   27   28   29   30
--------------------------------------------------------------------------------
BENOR  23    5    4    -    2    4    -    -    -    -    -    -    -    -    -
BRIBE   -    -    1    -    -    -    -    -    -    -    -    -    -    -    -
CASFL   8    3   28   24   23   15   28    5   22   41   59   10    -    -    -
       35    4   40   28   17   17   17    7   15   33   32    6    -    -    -
CRIST  61    -    -    -    -    -    -    -    -    -    -    -    -    -    -
       84   21   57   18    -   70   19    -   10   78   73    -    -    -    -
ELTMA  13    -   45    -    -    -   47    6    -    -    -    -    -    -    -
GONRU 100   60   71   61   63   72   77   12   54   72   84    7    -    -    -
HERCA  37   48   30    -   24   28   21   27   17    3   15    -    2    9    5
HINWO   -   16    9    1    -    -    -    2    -   33   32   59    3    3    -
KACJA   -   42    7   11    9    -   38   10    -    -   36   26    -   12    7
       17    -    -  101   20    -    -    2    -    -    -    -    -    -    -
        1   11   22    3    -    -   36    9    -    -    -    -    -    -    -
        -   31   16   13    -   35   43    7    -    -    1    -    -    -    -
KOSDE   -    -    -    -    -    -    -    -    -    -    -    -    -    -    -
LUNRO  68   87   78   64   76   37   27    1   62    -    -    -    -   50   32
MOLSI   -   11    3   30    -    -    -    -   29    -   63  171   55   33    6
       95    5    1    1    -    3    -    2    1    1   13   19   10    3    3
        -    -    -    -    -    -    -    -    -    -    -    -    -    -    -
        -    -    -    -    -    -    -    -    -    -    -    -    -    -    -
OCHPA   -   16   46   37   30   12    -    7   24   40   45   16    -    -    -
PRZDA  36   27    -    -   12    -   16    -    -   22    -    -    -   12    -
SLAST   -    9    4   10    -   17   38   16    -    -    4    -    -    -    -
STOEN  10    -    2    8    -    -   28    6    7   36   39   18    -    -    -
STRJO   9    -    8    -    4    1    -    -    -    2    -    -    -   25   19
        9    -    -    -    -    -    -    -    -    2    -    -    -   20    -
       25    -    -    -    -    -    -    -    -    5    -    -    -   33   31
YRJIL   -   41    -    5   37   11    -    1    -    -   35    -    2    -    -
--------------------------------------------------------------------------------
Sum   631  437  472  415  317  322  435  120  241  368  531  332   72  200  103

-- 
************************************************************
*   Sirko Molau                 *                          *
*   Abenstalstr. 13b            *              __          *
*   D-84072 Seysdorf            *       " 2B v 2B "        *
*   Germany                     *                          *
*   phone: +49-8752-869437      *             Shakespeare  *
*   email: sirko at molau.de       *                          *
*   www  : www.molau.de         *                          *
************************************************************




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