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(meteorobs) obs. Feb. 1/2 LANMA

Hello everybody,

Last night was one of those nights, that always come when you least 
expect it. Before this weekend, Saturdaynight seemed to have best papers. 
But much to the dissappointment of Koen and me, cirrus covered the sky 
all night. Sunday afternoon, it looked like last night would be lost to 
cirrus too. But in the evening the cirrus dissolved from sea land 
inwards, it seemed. When I quit my work behind the PC around local 
midnight, it was very clear, so I decided to set up my chair and 
observation sheets. When I had prepared and started observing just after 
midnight, there had developed some isolated streaks of cirrus again, and 
I feared that the night still would be lost, although they did not result 
in obstruction of my observing area in the sky at that moment. But not 
so. It was cold, 
with temperatures well below freezing point (-6 C), but virtually no 
wind: such a pleasant very quiet frosty night, the kind of nights I like 
best. During the second hour, the cirrus dissolved again completely. It 
was tremendously clear and dark, Lm +6.4! So I felt quite good. After 
half an hour, the cold got on the batteries of my flashlight, and they 
quit quite suddenly. So I had to go in again for fresh batteries. Of 
course, I found out that I had no spare ones left, so I had to take them 
from my memo-recorder (during this kind of nights without major streams, 
I directly note down on the sheet all meteor info, I don't use the recorder).
Originally, because I had library work to do today, I had planned only a 
short one hour session, but I couldn't get myself to quit so quick under 
these excellent conditions and prolonged the session to a well 2 hours. 
Then, a little bit reluctantly, I had to stop because of todays 
activities. Also, I began to feel a little bit tired (not so unexpected, 
given that I spend the larger part of the day behind my PC writing a paper).
Apart for the conditions, the night was memorable because of the good 
activity of slow meteors coming from a diffuse area on the ecliptic, 
roughly between the head of Leo and the heart of Cancer. Whatever these 
are (delta Leonids, delta Cancrids), there is certainly something active 
there. My 100th meteor of this year appeared, a slow +3 delta Leonid that 
appeared just below Procyon at 23:48 UT. The last meteor of the night was 
also the brightest: a magnitude 0 alfa Hydrusid in Auriga at 1:33 UT. I 
quit at 1:37 UT (2:37 local time), quite satisfied with a nice 
observational session. Below the data. Note: delta Cancrids and delta 
Leonids have been distinguished using velocity estimates, since the 
radiants partly overlap.

-Marco Langbroek

Date: February 1/2
Loc.: Voorschoten, the Netherlands, 4d 28' E, 52d 07' N


UT           Teff   Lm    dLeo  dCnc  aHya  Spo
23:10-0:25   1.03   6.4    2     2     1     8
0:25-1:37    1.09   6.4    2     1     2    14

TOTAL        2.12   6.4    4     3     3    22      32


stream        0    +1    +2    +3    +4    +5
Sporadics     0     1     6     4     7     4
d Leonids     0     0     0     2     1     1
d Cancrids    0     0     0     3     0     0
a Hydrusids   1     0     0     1     0     1