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THE ASTRONOMER Electronic Circular No 3670      2022 Jan 07 12.49UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise,  Basingstoke,
Hants, RG22 4PP,England.Telephone/FAX(01256)471074Int:+441256471074
INTERNET: GUY@TAHQ.DEMON.CO.UK      Backup: gmh@wdcc1.bnsc.rl.ac.uk
WORLD WIDE WEB                         http://www.theastronomer.org
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COMET C/2022 A1 (SARNECZKY)

Krisztian Sarneczky, Konkoly Observatory, reports the discovery of a
fast-moving comet during a visual inspection of three stacked 104-s
unfiltered CCD survey images taken at the Piszkesteto Observatory in Hungary
on Jan. 2.1 UT with the 0.60-m Schmidt telescope.  The object shows a
compact inner region (condensed false nucleus) about 8" x 10" in diameter
and a fan-shaped tail at least 20" long in a westward direction.  On a 312-s
stacked image, there is a faint outer diffuse coma about 40" in diameter,
with two jets in p.a. 230 and 350 deg.  The red magnitude was 18.5 as
measured within a circular aperture of radius 10".

     2022 UT             R.A. (2000) Decl.       Mag.   Observer
     Jan.  2.10924    9 06 28.99   +37 46 55.8   18.2   Sarneczky
           2.14409    9 05 48.21   +37 45 22.3   18.4     "
           2.15985    9 05 29.75   +37 44 40.1   18.4     "

After PCCP webpage, other CCD astrometrists have also reported on the
cometary appearance.  Forty-eight stacked 10-s exposures taken remotely on
Jan. 3.5 UT by H. Sato, Tokyo, Japan, using a 0.43-m f/6.8 astrograph
located near Mayhill, NM, USA, show a strongly condensed coma 12" in
diameter with no tail; the magnitude was 18.2 as measured within a circular
aperture of radius 7".6. 

The following parabolic orbital elements by S. Nakano (CBAT) are from 202
observations spanning Jan. 2-7 (mean residual 0".4).

     T = 2022 Jan. 31.12712 TT        Peri. = 201.17388
                                      Node  = 285.52086 2000.0
     q = 1.2529798 AU                 Incl. = 116.53264

The following ephemeris by Dan Green from the above orbital elements uses
photometric power-law parameters H = 18.5 and 2.5n = 8 (with several CCD
astrometrists reporting the comet near mag 17).

Date    TT    R. A. (2000) Decl.     Delta    r     Elong.  Mag.
2022 01 01    09 26.97   +38 26.2    0.414    1.335   142.2 17.6
2022 01 03    08 48.64   +37 01.1    0.375    1.325   151.5 17.3
2022 01 05    08 04.62   +34 18.9    0.344    1.315   162.0 17.1
2022 01 07    07 17.64   +30 02.4    0.325    1.306   172.2 17.0
2022 01 09    06 31.70   +24 20.9    0.319    1.298   168.8 16.9
2022 01 11    05 50.32   +17 54.9    0.327    1.290   156.6 17.0
2022 01 13    05 15.27   +11 34.9    0.348    1.283   144.7 17.1
2022 01 15    04 46.62   +05 56.8    0.380    1.277   134.1 17.2
2022 01 17    04 23.56   +01 13.7    0.419    1.272   125.0 17.4
2022 01 19    04 05.06   -02 36.5    0.465    1.267   117.4 17.7
2022 01 21    03 50.14   -05 41.7    0.514    1.263   110.9 17.9
2022 01 26    03 23.80   -11 04.2    0.649    1.255    98.3 18.4
2022 01 31    03 07.33   -14 23.0    0.791    1.253    89.0 18.8
(CBET 5090, extract)

Guy M Hurst

