Central Bureau for Astronomical Telegrams
IAUC 2222: 1941 VII
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 2223
Circular No. 2222
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
PERIODIC COMET DU TOIT-NEUJMIN-DELPORTE (1941 VII)
The orbit of this comet has been redetermined from 72 observations
1941 July 24 to Oct. 20. Two variation orbits were also calculated,
their revolution periods differing by the likely uncertainty,
+/- 10 days. Since the comet has made five revolutions since
1941, it might be expected that the ephemerides from these variation
orbits would correspond to Delta-T = +/- 50 days in 1970. However,
the comet passed close to Jupiter in 1954 and 1966. The effect of
the first approach was to cause the comet's period to increase from
5.5 to 5.9 years (putting it in 2:1 resonance with Jupiter's period),
and that of the second was to increase it further, to 6.3
years. The resonance acted like a mirror, in that the shorter the
period before 1954 the longer it would become after 1966. The
actual Delta-T range in 1970 is in fact -/+ 5 days, and the differential
perturbations in the other elements will limit even more the region
in the sky where the comet must be, particularly in August, when it
will be about at its brightest. In 1958 extensive, but unsuccessful
searches were made for the comet. In 1970 the maximum brightness
will be 2 to 3 magnitudes fainter than in 1958, but every
opportunity should be taken to recover the comet on account of the
unique focusing effect that has occurred.
T = 1970 Oct. 8.1642 ET Epoch = 1970 Aug. 2.0 ET
Peri. = 115.6884 e = 0.508677
Node = 187.8938 1950.0 a = 3.413334 AU
Incl. = 2.8619 n = 0.1562917
q = 1.677050 AU P = 6.306 years
1970 ET R. A. (1950) Decl. Delta r Mag.
Apr. 4 15 53.90 -17 47.4 1.550 2.352 19.7
14 15 54.53 -17 27.2
24 15 52.34 -16 56.9 1.299 2.244 19.1
May 4 15 47.44 -16 17.6
14 15 40.32 -15 31.8 1.131 2.139 18.6
24 15 32.02 -14 44.0
June 3 15 23.83 -14 00.2 1.057 2.039 18.2
13 15 17.17 -13 27.1
23 15 13.22 -13 09.8 1.065 1.946 18.0
July 3 15 12.67 -13 11.0
13 15 15.88 -13 30.9 1.131 1.863 18.0
23 15 22.83 -14 07.3
Aug. 2 15 33.31 -14 56.9 1.228 1.791 18.0
12 15 47.09 -15 55.8
22 16 03.84 -16 59.3 1.340 1.735 18.0
Sept. 1 16 23.27 -18 02.9
11 16 45.09 -19 02.2 1.461 1.697 18.1
21 17 08.98 -19 52.7
Oct. 1 17 34.60 -20 30.7 1.592 1.678 18.3
11 18 01.61 -20 52.7
21 18 29.60 -20 56.4 1.737 1.681 18.5
31 18 58.20 -20 40.2
Nov. 10 19 27.03 -20 03.7 1.899 1.706 18.7
20 19 55.72 -19 07.6
30 20 24.01 -17 53.3 2.079 1.749 19.0
Dec. 10 20 51.68 -16 22.8
20 21 18.55 -14 38.9 2.276 1.810 19.4
Mag. = 15.0 + 5 log Delta + 10 log r
Delta-T = + 5d Delta-T = - 5d
1970 ET R. A. (1950) Decl. R. A. (1950) Decl.
Apr. 4 15 58.96 -17 04.9 15 50.58 -18 17.8
14 15 59.75 -16 43.3 15 51.21 -17 58.7
24 15 57.76 -16 12.7 15 48.98 -17 28.7
May 4 15 53.07 -15 34.2 15 44.00 -16 48.7
14 15 46.14 -14 50.7 15 36.81 -16 01.0
24 15 37.94 -14 06.6 15 28.47 -15 10.2
June 3 15 29.70 -13 27.4 15 20.32 -14 22.8
13 15 22.82 -12 59.1 15 13.83 -13 45.9
23 15 18.45 -12 46.6 15 10.20 -13 25.0
July 3 15 17.34 -12 51.9 15 10.11 -13 23.2
13 15 19.86 -13 15.3 15 13.90 -13 40.7
23 15 26.03 -13 54.5 15 21.53 -14 15.5
Aug. 2 15 35.66 -14 46.4 15 32.77 -15 03.9
12 15 48.54 -15 47.2 15 47.38 -16 01.8
22 16 04.36 -16 52.5 16 05.02 -17 04.3
Sept. 1 16 22.82 -17 58.1 16 25.38 -18 06.6
11 16 43.66 -18 59.7 16 48.17 -19 04.0
21 17 06.57 -19 53.2 17 13.02 -19 51.8
Oct. 1 17 31.24 -20 35.0 17 39.57 -20 26.0
11 17 57.36 -21 01.8 18 07.44 -20 43.3
21 18 24.54 -21 11.0 18 36.20 -20 41.3
31 18 52.43 -21 01.1 19 05.44 -20 18.7
Nov. 10 19 20.68 -20 31.4 19 34.76 -19 35.4
20 19 48.93 -19 42.2 20 03.80 -18 32.5
30 20 16.91 -18 34.6 20 32.30 -17 11.7
Dec. 10 20 44.38 -17 10.4 21 00.06 -15 35.4
20 21 11.16 -15 32.0 21 26.92 -13 46.5
1970 March 6 (2222) Brian G. Marsden
Read IAUC 2223
Our Web policy. Index to the CBAT/MPC/ICQ pages.
