Central Bureau for Astronomical Telegrams
IAUC 3167: HDE 245770; P/GIACOBINI-ZINNER; 1978b
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 3168
Circular No. 3167
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 Telex: 921428
Telephone: (617) 864-5758
HDE 245770
C. Bartolini, A. Guarnieri and A. Piccioni, Istituto di Astronomia,
Universita di Bologna; and A. Giangrande and F. Giovannelli,
Laboratorio di Astrofisica Spaziale, Frascati, report: "On 1977 Dec.
17 and 20 and 1978 Jan. 6 we performed UBV photoelectric photometry
of HDE 245770 in order to test our hypothesis on the x-ray flare-up
periodicity and the probable related optical emission of the
A0535+26-HDE 245770 system. The data, obtained with the 60-cm
reflector at Loiano, show significant light enhancement of the star
relative to the comparison star BD +26 876 during Dec. 17-20 and
successive fading up to Jan. 6. Between Dec. 20.99 and 21.11 UT,
about 12 hours after the x-ray flare-up observed by SAS 3 (IAUC
3154), we continuously monitored HDE 245770 and the comparison
stars BD +26 876 and BD +25 902. Our results are as follows:
1977/78 UT dU1 dB1 dV1 dU2 dB2 dV2
Dec. 17.12 +1.231 +0.983
20.99 +0.355 +1.205 +0.948 +4.507 +4.409 +3.710
21.11 +0.375 +1.225 +0.960 +4.526 +4.436 +3.728
Jan. 6.87 +0.382 +1.259 +0.981
The differences dU, dB and dV are in the sense HDE 245770 minus
comparison star, subscript 1 referring to BD +26 876, subscript 2 to
BO +25 902. Standard deviations are 0.009 magnitude on Dec. 17.12,
0.004 on Dec. 20.99 and 21.11, 0.015 on Jan. 6.87. Between the
first and last times it appears that the observed B-V of HDE 245770
increased by about 0.03 magnitude. The observed enhancement of
optical emission during the flare-up of the x-ray source gives a
direct argument strongly supporting identification of HDE 245770 with
A0535+26, a transient x-ray source with double eruptive events
separated by about 200 days and probably recurring with a period of
about 765 days."
PERIODIC COMET GIACOBINI-ZINNER
The following ephemeris, by D. K. Yeomans, is from Handb. Br.
Astron. Assoc. for 1978:
For dT = +1d
1978 ET R. A. (1950) Decl. Delta r dR.A. dDecl. Mag.
Apr. 2 16 15.90 + 2 27.9 2.754 3.440 -0m64 - 1'7 21.1
12 16 13.29 + 4 19.8 -0.68 - 2.0
22 16 08.50 + 6 17.5 2.450 3.304 -0.71 - 2.4 20.6
May 2 16 01.64 + 8 15.7 -0.73 - 2.9
12 15 53.01 +10 07.3 2.245 3.163 -0.74 - 3.4 20.3
22 15 43.20 +11 45.0 -0.73 - 4.0
June 1 15 32.95 +13 02.3 2.150 3.016 -0.71 - 4.5 20.0
11 15 23.12 +13 54.5 -0.67 - 4.9
21 15 14.54 +14 20.2 2.151 2.863 -0.63 - 5.1 19.7
July 1 15 07.84 +14 20.4 -0.58 - 5.2
11 15 03.44 +13 58.1 2.213 2.705 -0.54 - 5.2 19.5
21 15 01.56 +13 17.2 -0.51 - 5.0
31 15 02.23 +12 21.6 2.299 2.541 -0.48 - 4.7 19.4
Aug. 10 15 05.40 +11 14.8 -0.47 - 4.4
20 15 10.96 + 9 59.9 2.375 2.371 -0.47 - 4.1 19.1
30 15 18.78 + 8 39.4 -0.48 - 3.7
Sept. 9 15 28.77 + 7 15.3 2.421 2.195 -0.50 - 3.2 18.8
19 15 40.86 + 5 49.5 -0.54 - 2.8
29 15 54.99 + 4 23.2 2.424 2.013 -0.58 - 2.3 18.5
Oct. 9 16 11.18 + 2 58.1 -0.64 - 1.8
19 16 29.47 + 1 35.4 2.381 1.828 -0.71 - 1.2 18.0
29 16 49.92 + 0 16.5 -0.81 - 0.7
Nov. 8 17 12.67 - 0 57.1 2.295 1.640 -0.91 - 0.1 17.5
18 17 37.82 - 2 03.8 -1.04 + 0.5
28 18 05.53 - 3 02.0 2.179 1.454 -1.20 + 1.1 16.8
PERIODIC COMET WILD 2 (1978b)
P. Wild, Astronomical Institute, Berne University, provides
further precise positions as follows:
1978 UT R. A. (1950) Decl.
Jan. 25.73403 5 19 00.02 +19 53 16.9
25.75556 5 18 59.12 +19 53 21.1
The following orbital elements, by B. G. Marsden, indicate
that this is a short-period comet that passed very close to Jupiter
in 1974. Wild also remarks on the comet's short period.
T = 1978 June 14.90 ET
Peri. = 39.48 e = 0.5566
Node = 136.33 1950.0 a = 3.3583 AU
Incl. = 3.26 n = 0.16015
q = 1.4891 AU P = 6.15 years
1978 ET R. A. (1950) Decl. Delta r m1
Jan. 22 5 21.18 +19 46.0
Feb. 1 5 16.61 +20 07.5 1.232 1.999 13.5
11 5 16.24 +20 34.2
21 5 20.23 +21 05.3 1.309 1.881 13.3
Mar. 3 5 28.39 +21 38.5
13 5 40.44 +22 10.7 1.401 1.771 13.2
1978 January 30 (3167) Brian G. Marsden
Read IAUC 3168
Our Web policy. Index to the CBAT/MPC/ICQ pages.
