IMO:n sirkulaareja, Leonidit 2002



Sirkulaari 22.11.2002:


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           I M O   S h o w e r   C i r c u l a r

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                       LEONIDS 2002


Two strong activity peaks of the Leonid meteor shower were 
predicted. The times fell between 03:48 to 04:04 UT for the 
first one, and between 10:23 to 10:47 UT for the second peak,
both on November 19, 2002.

A first activity analysis from the reports of 86 observers, 
who logged 19443 Leonids, is given below. The ZHR refers to 
a stellar limiting magnitude of +6.5, a radiant elevation of 
90 deg, and counts of single observers. A population index 
of r=2 was applied, although the inspection of data suggests 
a large abundance of faint meteors, thus a larger r. The 
ZHRs would increase likewise.

The peak time of the first maximum is 04:10 UT with ZHR=2350.
The second peak is found near 10:50 UT or a few minutes ear-
lier with ZHR=2660. Both peaks occurred later than the pre-
dictions by about the same time lapse. The predictions of
the Leonid stream model of Vaubaillon (WGN 30:5, 2002) are
closest to reality according to this first analysis.

--------------------------------------
Nov  UT   Sollong   N   LEO   ZHR   +-
--------------------------------------
16  2000  234.257   2    10     19   6
17  0300  234.551   6    15      6   2
17  2200  235.349  13    96     37   4
18  0400  235.601  12    78     26   3
18  2000  236.273  21   431     98   5
18  2300  236.399  22   195    100   7
19  0000  236.441  26   330    101   6
19  0110  236.490  27   271    188  11
19  0140  236.511  24   218    201  14
19  0210  236.532  21   266    249  15
19  0220  236.539  20   332    305  17
19  0240  236.553  36   342    300  16
19  0255  236.564  16   157    275  22
19  0306  236.571  22   205    375  26
19  0316  236.578  28   329    497  27
19  0327  236.586  27   484    583  27
19  0335  236.591  48  1047    756  23
19  0343  236.597  20   412    930  46
19  0345  236.599  32   719   1162  43
19  0353  236.604  35   768   1344  49
19  0358  236.608  47  1341   1542  42
19  0402  236.610  36  1248   1966  56
19  0408  236.615  31  1335   2353  64
19  0413  236.618  17   912   2332  77
19  0418  236.622  30  1253   1995  57
19  0426  236.627  35   933   1367  45
19  0436  236.634  38   681    989  38
19  0447  236.642  24   416    635  31
19  0500  236.651  31   395    675  34
19  0518  236.664  50   505   1014  45
19  0535  236.676  22   189    572  42
19  0555  236.690  15    97    144  15
19  0620  236.707  15    87    142  15
19  0800  236.777  14   166    272  21
19  0905  236.823  21   217    307  21
19  0930  236.840  27    99    152  15
19  0947  236.852  21    72    267  32
19  1000  236.861  21   128    293  26
19  1010  236.868  31   192    707  51
19  1018  236.874  19   396    907  46
19  1023  236.877  15   134    965  83
19  1030  236.882  27   288   1364  80
19  1040  236.889  26   350   2108 112
19  1050  236.896  28   587   2656 110
19  1100  236.903  19   297   1061  62
19  1112  236.912  17   130    490  43
19  1135  236.928   7   184    366  27
19  2200  237.366   6    99    123  12
20  0500  237.660  11     4     10   5
---------------------------------------------

Solar longitudes refer to equinox J2000.0, N is the number
of observing periods involved in the average ZHR, LEO is the
number of Leonid meteors. The error of the ZHR is simply
ZHR/sqrt(LEO) here. No special zenith exponent was applied
to account for non-geometrical effects in radiant elevation
correction.

 
We are very grateful to the enthusiastic community of meteor
observers who have sent in their results, mostly through the
online express form. All observers are encouraged to send
their FULL DATA including magnitudes and possibly shorter
time-bins for the counts within the next week.

(An error in the online form script has lead to erroneous out-
put in geographical latitude and radiant elevation; the actual 
results presented here are not affected though.)


V. Krumov, M. Gyssens, R. Arlt
2002 November 22

Takaisin Leonidit 2002 uutissivulle

Takaisin meteorijaoston kotisivulle