Astroalert : Méteors

[Chris74]

Pour info :

 

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This Is SKY & TELESCOPE's AstroAlert for Meteors

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There exists a small possibility that the Earth may encounter debris from

the newly discovered comet P/2005 JQ5 (Catalina). Mikail Maslov writes

in meteorobs:

 

"Its orbit seems to be quite interesting because it lies close to the

Earth's one. In 2005 apparition ascending node of the comet is at 0.090 AU

inside the Earth's orbit. The Earth passes closest to it on 01.07.2005. But

orbital inclination of the comet is low - only 5.679 deg. So the minimal

distance between two orbits is almost 4 times lower (0.024 AU) and

corresponds to 12-13.06.2005. In 2005 the Earth will pass this point only

about 7 days before the comet. In general, even 0.024 AU is still quite

large to expect any significant activity (also, the comet is very small -

absolute magnitude is only 17.5). Intensity of dust ejection of this comet

should be about 100 times lower than of, say, 21P Giacobiny-Zinner.

 

So, if 21 can give stormy encounters, the new comet should be able to give

ZHRs of several dozens - from very favorable encounters. But such activity -

or even ZHRs about 10 - are still something very detectable. So I think,

there is still the possibility of enhancements in case of favorable trails

position.

 

The orbit of the comet is still quite uncertain, so to make more

reliable conclusions we have to wait a little for more accurate

elements. The given orbit is rather stable, the perihelion distance during

the period 1901-2100 changes between 0.80 and 0.85 AU Minimal distance

between two orbits was about 0.036 AU at the previous comet perihelion in

2001. In the following years this minimum will continue to make small

changes, but in total it will slightly decrease to 0.015 AU to the middle of

21 century. So, unless more accurate elements make dramatic difference, the

comet will be worth attention and trail computation. The current elements

suppose the radiant in RA=242 deg, Dec=-09 deg. Any meteors from this

radiant would be very slow (Vg=16 km/s). Radiant culminates at 0:15 local

time and is more favorable for southern hemisphere, but in northern one

observations are also very possible."

 

The position for this radiant lies in extreme northwestern Scorpius. The

closest bright stars lie four degrees to the northeast (Delta and Epsilon

Ophiuchi, aka "Yeds". If your skies are clear on the night of June 12/13, I

encourage you to view the southern skies for any possible activity from this

radiant.

 

For the basics on meteor observing I invite you to visit:

http://skyandtelescope.com/observing/objec...rticle_98_1.asp

 

Sky & Telescope and the American Meteor Society are interested in any

results you may obtain. You may send these results to observers@skypub.com

and lunsford@amsmeteors.org

 

Clear Skies!

 

Robert Lunsford

American Meteor Society