(meteorobs) Lyrids 1-rev. encounter in 2006

[Esko Lyytinen]

Hi all,

The 1-rev. Lyrids trail passes quite close to the Earth in 2006, but a 
little too far away for a definite outburst. This is about like last year.
In 2005 it passed by about 0.0017 AU inside the Earth orbit. Now it will 
pass at a little bigger distance of 0.0020 Au.

In a private massage Sirko Molau tells that some level peak may have 
been present in the (2005) video-observations around the time of 
predicted encounter:

" ..when I analysed our 2005 Lyrid video observations I found enhanced 
activity
betwen about 00:30 and 2_30 UT on April 22. 
(http://groups.yahoo.com/group/imo-news/message/1559)
.. Our result fits quite well, even though its no proof since 
interference from the moon and twilight could explain the result as well."

The peak time was predicted at 1:30.

In this year the time of encounter is predicted at sol.long 32.031 . 
This is April, 22 at 9:25 UT. This can be possibly observed in Americas.

Assuming the trail density-decline (outside of trail-center) to be like 
in young Leonids trails, a comparison with last year would yiel now 
about 60% the (eccess) rates of last year.
The meteors from this trail encounter are expected to be mainly dim. So 
under very good conditions and/or sensitive video cameras this increase 
may be detecred, maybe not? (The Moon is a little past last quarter, so 
makes harm especially for faint meteor observing.)

Encounters other than the 1-rev. trail can not be predicted, because the 
parent comet motion would need to be known back to the return of ejection,
Some level outbursts that were not from the 1-rev. have been mainly 
observed when the 1-rev. trail is quite nearby like now. This kind of 
outbursts were observed (among others) in 1945 and 1946. This was 60 
years ago which means that there are 5 Jupiter orbital periods and 2 
Saturn orbital periods in  between.
On the other hand if those encounters were for example from 2-rev. 
trails, then in the first return of these meteoroids, Jupiter would have 
been at about the opposite side of the Sun, which would make the 
situation quite differet and not especially promising.
However, it is worth to try to observe now also possible ouburtsts that 
are not from the 1-rev. trail. I can not give any timing prediction for 
this, other than the annual maximum.

clear skies,
Esko Lyytinen