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From: TerryMosel@aol.com
Date: Mon, 11 Feb 2002 18:58:28 EST
Subject: Comet Ikeya-Zhang latest

Hi all,

At last I've managed to get a quick glimpse of this beast - low through
scudding clouds near the horizon, but it was unmistakeable in 30x80 binocs.
I couldn't see it long enough, or with enough comparison stars visible at the
same time, to do a proper magnitude estimate, but I would say it was closer
to mag 7 than mag 8, i.e. brightening nicely.

The provisional orbital elements sent with my first alert have had to be
revised considerably! Fortunately the new ones indicate even better prospects
for us - it will be brighter, higher up, and visible for longer than first
thought! It should reach 4th mag in the 3rd week of March.

The new elements are courtesy of Prof Mark Bailey (Armagh Observatory) & Dr
Alan Fitzsimmons (QUB):

e=3D1.0
q=3D0.510190
i=3D28.1176
peri(small omega)=3D34.2075
node(large omega)=3D93.2016
T=3D2002 March 18.9118

If you haven't the appropriate software, here's an ephemeris for the next 10 days:

February  2002                 Positions for 00:00 ET, Times in UT
 Day     R.A. 1950 Dec   R.A. 2000 Dec  Mag  D      R    Elong
 11/12   0 25.5  -12.06   0 28.1  -11.49   7.2   1.42   0.92    40
 12/13   0 27.4  -11.30   0 30.0  -11.14   7.1   1.41   0.91    40
 13/14   0 29.3  -10.53   0 31.9  -10.37   7.0   1.39   0.89    39
 14/15   0 31.3  -10.16   0 33.8   -9.59   6.8   1.38   0.87    39
 15/16   0 33.2   -9.38   0 35.8   -9.21   6.7   1.36   0.86    39
 16/17   0 35.2   -8.59   0 37.7   -8.42   6.5   1.35   0.84    38
 17/18   0 37.2   -8.19   0 39.7   -8.02   6.4   1.33   0.82    38
 18/19   0 39.2   -7.38   0 41.7   -7.21   6.2   1.32   0.81    38
 19/20   0 41.2   -6.56   0 43.7   -6.40   6.0   1.30   0.79    37
 20/21   0 43.2   -6.13   0 45.7   -5.57   5.9   1.29   0.77    37
 21/22   0 45.2   -5.29   0 47.8   -5.13   5.7   1.27   0.76    37
 22/23   0 47.3   -4.44   0 49.8   -4.28   5.5   1.25   0.74    36

Note that the positions are for midnight on the double date given, however
the comet is sufficiently bright that plotting an approximate position should
be sufficient to locate it.  Positions for both 1950 (old editions of
Norton's etc) and J2000 are given. D = Distance from Earth in AU's, R = dist
from Sun in AU's, Elong = angular elongation from Sun in degrees.

Good Luck.

Also a quick reminder that all will be welcome at the IAA public observing
night at Wildfowl & Wetlands Trust, Castle Espie, Comber, Co Down, at 7.30 p.m., 
Saturday 16 February. Planetarium shows & talks if cloudy. Free to IAA
& WWT members, 2 for others (charged by the WWT, not the IAA!).

Terry

Last Revised: 2002 February 12th
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