Circular No. 7224

Central Bureau for Astronomical Telegrams INTERNATIONAL ASTRONOMICAL UNION

Mailstop 18, Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.

IAUSUBS@CFA.HARVARD.EDU or FAX 617-495-7231 (subscriptions) BMARSDEN@CFA.HARVARD.EDU or DGREEN@CFA.HARVARD.EDU (science)

URL http://cfa-www.harvard.edu/iau/cbat.html ISSN 0081-0304

Phone 617-495-7244/7440/7444 (for emergency use only)

COMET C/1999 N2 (LYNN)

Additional CCD astrometry:

1999 UT α_{2000} δ_{2000} m_{2} Observer
July 14.89331 9^{h}58^{m}15.^{s}16 −13^{o}20′30′′.6 11.7 Jacques
14.89454 9 58 15.98 −13 20 21.1 11.6  _{”}
14.89524 9 58 16.47 −13 20 15.6 11.6  _{”}
14.89590 9 58 16.94 −13 20 10.3 11.6  _{”}
14.89664 9 58 17.51 −13 20 03.9 11.1  _{”}
14.92073 9 58 34.48 −13 16 51.8 11.4  _{”}
14.92247 9 58 35.75 −13 16 37.1 11.3  _{”}
15.36050 10 03 41.58 −12 18 33.2 14.3 Garradd
15.36175 10 03 42.46 −12 18 23.0 14.4  _{”}
15.36219 10 03 42.76 −12 18 19.7 14.4  _{”}
15.38878 10 04 01.09 −12 14 48.1 12.4 Zoltowski
15.39245 10 04 03.60 −12 14 18.8 12.4  _{”}
15.39631 10 04 06.23 −12 13 48.2 12.4  _{”}
15.40087 10 04 09.37 −12 13 12.0 12.4  _{”}

C. Jacques and L. Duczmal (Wykrota). 0.3-m f/3.3 reflector. G. J. Garradd (Loomberah). 0.45-m f/5.4 reflector. Thin ion tail in p.a.

141^{o} with an apparent disconnection event (starting at 615′′ in p.a. 138^{o}, continuing for at least 12′); coma diameter 8′.5. Rainy conditions.

F. B. Zoltowski (Woomera). 0.30-m f/10 Schmidt-Cassegrain reflector. Preliminary parabolic orbital elements by B. G. Marsden:

T = 1999 July 23.099 TT  ω = 357.^{o}816
Ω = 254.322 }2000.0
q = 0.76096 AU  i = 112.443
1999TT α_{2000}  δ_{2000}  Δ  r  ϵ  β  m_{1}
July 15 9^{h}59.^{m}51 −13^{o}06.^{′}5 0.580 0.777 49.^{o}5 95.^{o}9 7.2
16 10 10.90 −10 54.7 0.591 0.774 49.3 95.4 7.2
17 10 21.61 − 8 45.5 0.603 0.770 49.1 94.7 7.3
18 10 31.65 − 6 40.0 0.618 0.768 48.9 93.7 7.3
19 10 41.03 − 4 39.1 0.634 0.765 48.8 92.7 7.3
20 10 49.79 − 2 43.3 0.652 0.763 48.7 91.4 7.4
21 10 57.95 − 0 52.8 0.671 0.762 48.6 90.1 7.5
1999 July 15  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1999 CBAT  Daniel W. E. Green