(meteorobs) Lyrids 1-rev. encounter in 2006

[Mikhail Maslov]

Hello, Esko and all,

Thanks for the info. If I understand correctly, the fact of 1st rev
trail perturbation means that background Lyrids stream is also can
be moved closer to the Earth orbit, like during Perseids 2004. If it
is so, besides possible activity from 1st rev. trail usual Lyrid
maximum can be more prominent this year. In 2005 the situation was
quite similar, but there was unfavorable conditions with moolight.
This year is much better (though not perfect) to check probable
enhancements in Lyrid activity.

Best regards, Mikhail



EL> Hi all,

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

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

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

EL> The peak time was predicted at 1:30.

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

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

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

EL> clear skies,
EL> Esko Lyytinen

EL> ---
EL> Mailing list meteorobs: meteorobs at meteorobs.org
EL> To UNSUBSCRIBE, email: owner-meteorobs at meteorobs.org
EL> http://lists.meteorobs.org/mailman/listinfo/meteorobs