Central Bureau for Astronomical Telegrams
IAUC 2850: 1975j; 1975k
The following International Astronomical Union Circular may be linked-to from your own Web pages, but must not otherwise be redistributed (see these notes on the conditions under which circulars are made available on our WWW site).
Read IAUC 2851
Circular No. 2850
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
Cable Address: SATELLITES, NEWYORK
Western Union: RAPID SATELLITE CAMBMASS
COMET MORI-SATO-FUJIKAWA (1975j)
The following positions have been reported:
1975 UT R. A. (1950) Decl. m1 Observer
Oct. 6.79236 8 21 50.5 + 2 35 52 10 Suzuki
7.41979 8 22 20.01 + 2 12 50.2 Moore
7.44410 8 22 21.14 + 2 11 55.3 "
8.77368 8 23 22.60 + 1 22 03.2 10 Shibasaki
8.78112 8 23 23.00 + 1 21 45.6 "
9.79097 8 24 09.10 + 0 43 03.1 10 Kojima
9.81389 8 24 09.79 + 0 42 10.2 "
11.72014 8 25 34.8 - 0 32 57 10 Herald
K. Suzuki (JCPM Oi Station). Measurer: T. Urata. Communicated by
K. Osawa.
E. Moore (Joint Observatory for Cometary Research). 37-cm f/2
Schmidt camera. Measurer: E. Tedesco. Communicated by Tedesco.
H. Shibasaki (Tokyo Astronomical Observatory). Measurer: H. Kosai.
Communicated by Osawa.
N. Kojima (Ishiki, Aichi). Measurer: Kosai. Communicated by Osawa.
D. Herald (Woden, near Canberra). A scaled position.
The comet is diffuse with a central condensation, but without
a tail. The following parabolic orbits, by Z. Sekanina, satisfy,
respectively, the Oct. 6-11 and 7-9 observations within 3". The
second set of elements leaves residuals of -4" on Oct. 6 and -5" on
Oct. 11 in declination, while the fits in right ascension are
almost perfect. The ephemeris is from the first orbit.
T = 1975 Dec. 23.50 ET T = 1975 Dec. 20.21 ET
Peri. = 243.98 Peri. = 240.99
Node = 277.82 1950.0 Node = 277.62 1950.0
Incl. = 90.77 Incl. = 89.68
q = 1.6371 AU q = 1.6800 AU
1975 ET R. A. (1950) Decl. Delta r m1
Oct. 15 8 27.91 - 2 49.4 1.933 1.879 10.0
20 8 31.18 - 6 34.2
25 8 34.08 -10 42.1 1.741 1.819 9.6
30 8 36.52 -15 14.7
Nov. 4 8 38.41 -20 13.1 1.576 1.766 9.3
m1 = 5.8 + 5 log Delta + 10 log r
The second set of elements gives correctibns of -0m.01, +0'.5 to the
first ephemeris place and -0m.16, +13'.3 to the last one.
COMET SUZUKI-SAIGUSA-MORI (1975k)
The following precise positions have been communicated:
1975 UT R. A. (1950) Decl. m1 Observer
Oct. 6.81152 11 11 40.07 +43 36 55.6 7 Suzuki
7.42604 11 12 10.13 +43 34 32.0 Moore
7.44826 11 12 11.22 +43 34 29.4 "
7.49549 11 12 13.72 +43 34 19.1 "
8.79931 11 13 25.14 +43 28 03.9 7 Shibasaki
8.81042 11 13 25.61 +43 28 01.3 "
8.81458 11 13 25.54 +43 28 01.7 "
K. Suzuki (JCPM Oi Station). Measurer: T. Urata. Communicated by
K. Osawa.
E. Moore (Joint Observatory for Cometary Research). 37-cm f/2
Schmidt camera. Measurer: E. Tedesco. Communicated by Tedesco.
H. Shibasaki (Tokyo Astronomical Observatory). Measurer: H. Kosai.
Communicated by Osawa.
The comet is a diffuse object with a central condensation, but
nothing is reported about a tail. The following parabolic elements,
derived by Z. Sekanina, satisfy the above observations within
3". Because of a very short arc covered by the observations and
their somewhat unfavorable distribution, the elements and the
resultant ephemeris are rather uncertain.
T = 1975 Oct. 13.87 ET Peri. = 150.39
Node = 215.53 1950.0
q = 0.8357 AU Incl. = 118.01
1975 ET R. A. (1950) Decl. Delta r m1
Oct. 13 11 18.70 +42 53.6
15 11 22.38 +42 25.6 0.598 0.836 7.6
17 11 27.19 +41 45.6
19 11 33.60 +40 47.9 0.456 0.841 7.0
21 11 42.37 +39 21.8
23 11 54.77 +37 06.9 0.314 0.853 6.3
25 12 13.15 +33 19.2
m1 = 9.5 + 5 log Delta + 10 log r
The elements indicate a possibility of a close approach of the
comet to the earth at the end of October. If it is so, the comet
might become a naked-eye object for a short period of time in late
October in the northern hemisphere and in early November in the
southern hemisphere. If the comet develops a tail, there is also
a possibility that the earth might pass through it on or around
October 30.
P. Maley (Houston, Texas, 13-cm f/5 refractor) reports a total
visual magnitude of 8.2 and a coma 5' in diameter on Oct. 9.46 UT.
1975 October 14 (2850) Zdenek Sekanina
Read IAUC 2851
Our Web policy. Index to the CBAT/MPC/ICQ pages.
