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(meteorobs) Lyrids 1-rev. encounter in 2006   Message List  
Reply Message #30434 of 41438 |

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

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Wed Apr 19, 2006 10:06 am

esko.lyytinen@...
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Message #30434 of 41438 |
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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...
Esko Lyytinen
esko.lyytinen@... Send Email
Apr 19, 2006
10:08 am

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...
Mikhail Maslov
ast0@... Send Email
Apr 19, 2006
1:25 pm
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