Circular No. 7251

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 R1 (SOHO)

D. A. Biesecker, SM&A Corporation and Goddard Space Flight Center, reports observations of what is presumably a comet, not a Kreutz sungrazer, discovered by T. Lovejoy in SOHO/LASCO C3 data and later also recognized in earlier C2 data. Astrometry and orbital computations are given on MPEC 1999-R19. Biesecker also provides the following LASCO magnitudes, reduced using the Hipparcos Input Catalogue: Sept. 5.47 UT, 6.6; 5.53, 6.5; 5.57, 6.4; 5.61, 6.3; 5.65, 6.2; 5.70, 6.2; 5.78, 6.4; 5.82, 6.4; 5.86, 6.7; 5.90, 6.9; 5.99, 6.9; 6.07, 7.4; 6.15, 7.4. No tail was detected.

1999 UT  α_{2000}  δ_{2000}
Sept. 4.896  10^{h}48.^{m}8  + 7^{o}17′

COMET C/1999 H1 (LEE)

Continuation to the ephemeris on IAUC 7233 from the orbital elements on MPC 35553:

1999TT α_{2000} δ_{2000} Δ r ϵ β m_{1}
Sept. 9 5^{h}33.^{m}32 +54^{o}58.^{′}3 1.033 1.337 81.^{o}8 48.^{o}2 8.3
10 5 25.80 +55 32.2 1.017 1.351  83.7 47.8 8.3
11 5 17.75 +56 05.2 1.002 1.366  85.7 47.3 8.4
12 5 09.13 +56 37.2 0.986 1.380  87.6 46.8 8.4
13 4 59.91 +57 07.7 0.971 1.394  89.7 46.2 8.4
14 4 50.08 +57 36.3 0.957 1.409  91.7 45.5 8.4
15 4 39.61 +58 02.5 0.943 1.423  93.8 44.8 8.4
16 4 28.49 +58 25.9 0.930 1.438  95.9 44.1 8.4
17 4 16.72 +58 45.9 0.917 1.452  98.0 43.3 8.4
18 4 04.34 +59 01.8 0.905 1.467 100.2 42.4 8.4
19 3 51.36 +59 13.3 0.893 1.481 102.4 41.5 8.5
20 3 37.85 +59 19.5 0.883 1.496 104.7 40.5 8.5
21 3 23.89 +59 20.1 0.873 1.510 106.9 39.5 8.5
22 3 09.57 +59 14.4 0.864 1.524 109.2 38.5 8.5
23 2 55.01 +59 02.0 0.856 1.539 111.5 37.4 8.5
24 2 40.34 +58 42.7 0.848 1.553 113.8 36.2 8.6
25 2 25.69 +58 16.2 0.842 1.568 116.1 35.1 8.6
26 2 11.19 +57 42.4 0.837 1.582 118.3 33.9 8.6
27 1 56.97 +57 01.5 0.833 1.596 120.6 32.7 8.6
28 1 43.13 +56 13.7 0.830 1.611 122.8 31.5 8.7
29 1 29.79 +55 19.3 0.828 1.625 125.0 30.3 8.7
1999 September 9  \begin{matrix}c \\ ◯ \end{matrix} Copyright 1999 CBAT  Brian G. Marsden