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(meteorobs) Jan 25/26 and 26/27 obs. LANMA and 55P/

Hello everybody,

Last week saw a number of clear nights after the almost 2 month period of 
very bad weather that started medio November. So both Koen Miskotte and I 
took advantage. Below the results of Sunday and Monday nights, 25/26 and 
26/27 Jan 1998.

I have started to shift from 'after midnight'-sessions to evening 
sessions about one year ago, forced by a heavy daytime workload. So far, 
it turns out prosperous. It is a good way of keeping up the expertise and 
spirit when large nighttime sessions are not possible. There are boh 
drawbacks as well as advantages. The sporadic activity level is usually 
a bit lower before midnight, but on the other hand the meteors are slower 
and thus more rewarding. In general, these early hours are a little bit 
neglected and can yield surprises perhaps.
Around this time of the year, the only streams active (all minor) all are 
well visible in the late evening. Active are the late delta Cancrids 
(note that IMO's 'early Virginids' (and my meteors classified as such below) 
are, I suspect, in fact late Northern delta Cancrids) that provide you 
with 1-2 meteors an hour, and the alfa Hydrusids which have a very low 
activity level (0-1 per session of 2-3 hours; for the Netherlands (52d 
North) the radiant stays rather low in altitude).

The 25/26 Jan session was a little bit short: after 1.4 hours clouds 
developed. But the afternoon of Jan 26 saw cristal clear skies. A front 
with a sharp edge was situated 200 km to the north and visible at appr. 1 
degree altitude above the horizon. Because predictions were that it would 
move southward during the night, I decided to start rather early, after 
seeing the forecast and (like the night before) a look on comet 
55P/Tempel-Tuttle.
After about one hour under clear LM6.2-6.3 skies, I was telephoned by 
Casper and Robert who were...trying to find Tempel-Tuttle from Alphen wih 
a 9x63 bino. They could not locate it and asked whether I had seen it 
(which I had) and where to look. It soon turned out that somehow they had 
managed to get a wrong (!) finder chart from the internet (while I had 
phoned Robert the correct positions that afternoon!). So telephonically I 
managed to guide casper (with telephone in the one hand and bino in the 
other) 'virtual' from star to star to the correct position. They failed 
to see it however. Since it probably had moved in the 1.5 hours since I 
saw it myself, I rechecked and phoned Casper again, describing in detail 
where it was positioned. Well, they failed again, and the whole costed me 
3 quarters of an hour valuable observing time.... I think their bino was 
slightly too weak, and in addition he was indeed more difficult this 
evening due to the proximity of a grouplet of mag. 7 stars. And well, 
perhaps the eyes of the two gentlemen are not that good too. Anyway, 
after this unplanned break I rsumed, untill around 0:30 local time the 
front moved in and I stopped.

Below the data. Particularly attractive meteors were a long trailing (1.5 
secs!) mag +1 delta Cancrid on 25/26, and another long mag. 0 'early 
Virginid'/late delta cancrid at 26/27 with a short persisting train.

-Marco Langbroek




Obs: Marco Langbroek (LANMA)
LOc: Voorschoten, the Netherlands, 4d 28' E, 52d 07' N


date: January 26/27, 1998

UT            Teff   Lm    d Cnc  Vir   aHya   Spo
19:55-21:05   1.12   6.3    0      1      0     8
21:43-22:40   0.90   6.2    0      1      1     7
22:40-23:30   0.76   6.3    1      2      0     8

TOTAL         2.78  <6.3>   1      4      1     23     29


stream      0    +1    +2    +3    +4    +5
Sporadics   0    0     3     11     6     3
Virginids   1    0     1      0     2     0
d Cancrids  0    0     0      1     0     0
a Hydrusids 0    0     1      0     0     0


Date: Jan 25/26


UT            Teff   Lm   d Cnc  Vir   aHya   Spo    TOTAL
20:35-22:06   1.43   6.2    1     1      0     12     14


stream       +1    +2    +3    +4    +5
Sporadics     0     1     5    3      3
d Cancrids    1     0     0    0      0
Virginids     0     1     0    0      0