THE ASTRONOMER Electronic Circular No 581 1991 Nov 24 16.40UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise, Basingstoke,
Hants, RG22 4PP,England. Telephone/FAX(0256)471074 Int:+44256471074
Telex: 9312111261 Answerback: TA G JANET BOXES:
GMH at UK.AC.CAM.ASTRONOMY.STARLINK or GUYH at UK.AC.SUSSEX.CLUSTER
TELECOM GOLD: 10074:MIK2885 PRESTEL 256471074
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PERIODIC COMET TSUCHINSHAN 1 (1991c1)
S. Nakano, Sumoto, Japan, reports the recovery of this comet by
T. Seki with the 0.60-m reflector at Geisei. The comet has a tail
30" long in p.a. 300 deg and is diffuse with central condensation.
Seki's observations yield a correction to the prediction on MPC
13057 of Delta(T) about +0.02 day:
1991 UT R.A. (1950) Decl. m1
Nov. 8.84306 12 30 53.70 + 4 17 18.5 17
11.83056 12 38 14.92 + 3 39 39.0 18
11.84340 12 38 16.77 + 3 39 30.1
11.85208 12 38 18.09 + 3 39 19.9
IAUC 5383
The comet appears to be much fainter (m1) than predicted in the
ICQ Handbook (1991).
1991 VG - A RETURNING SPACECRAFT?
As I announced at the 1991 TA AGM, a report has been received from
the Central Bureau mentioning discovery by J.V.Scotti of a fast-
moving object on Nov 6 at V=20.7. From 24 precise positions
obtained using the 0.91-m Spacewatch Telescope, Brian Marsden
derived the following elements:
Epoch = 1991 Oct. 31.0 ET
T = 1992 Jan. 14.1186 ET Peri. = 260.8887
e = 0.065262 Node = 212.9200 1950.0
q = 0.971470 AU Incl. = 0.3913
a = 1.039297 AU n = 0.9302397 P = 1.060 years
Dan Green comments on IAUC 5387 that these elements are
remarkably similar to those of the earth. The minimum geocentric
distance is 0.0031 AU on Dec 5.4 UT (H=28.8). Geocentric solutions
yield e > 3. The object might be a returning spacecraft.
The following additional information is given in view of the
considerable interest shown in this object recently:
Orbital elements for additional epochs (cf. IAUC 5387):
Epoch = 1991 Nov. 30.0 ET
T = 1992 Jan. 13.8337 ET Peri. = 293.8937
e = 0.078509 Node = 180.2000 1950.0
q = 0.966182 AU Incl. = 0.2182
a = 1.048499 AU n = 0.9180203 P = 1.074 years
Epoch = 1991 Dec. 10.0 ET
T = 1992 Jan. 5.7221 ET Peri. = 26.3867
e = 0.074974 Node = 78.8835 1950.0
q = 0.972669 AU Incl. = 1.5968
a = 1.051505 AU n = 0.9140861 P = 1.078 years
1991 ET R.A. (1950) Decl. Delta r V
Nov 24 2 54.52 - 3 23.7 0.009 0.995 19.9
25 2 55.13 - 5 41.6
26 2 55.86 - 8 22.7 0.008 0.993 19.7
27 2 56.74 -11 33.2
28 2 57.82 -15 21.5 0.006 0.992 19.4
29 2 59.18 -19 59.8
30 3 00.99 -25 44.0 0.005 0.990 19.2
Dec. 1 3 03.52 -32 57.2
2 3 07.44 -42 08.6 0.004 0.988 19.1
3 3 14.53 -53 50.3
4 3 32.20 -68 18.7 0.003 0.986 19.5
5 5 39.1 -84 14.4
6 13 51.8 -75 58.1 0.003 0.984 21.2
Guy M Hurst