Central Bureau for Astronomical Telegrams
IAUC 3095: 1977k; X-RAY BURSTS; LMC X-4; Cir X-1; AM Her; COMETARY NEBULA NEAR NGC 7023
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 3096
Circular No. 3095
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
PERIODIC COMET AREND-RIGAUX (1977k)
This comet has been recovered by R. E. McCrosky with the 155-cm
reflector at Harvard Observatory's Agassiz Station, as shown below.
Measurer: C.-Y. Shao. The object is stellar in appearance.
The correction to the prediction on IAUC 3034 is Delta-T = -0.01 day.
1977 UT R. A. (1950) Decl. m2
Aug. 15.32794 2 07 18.93 -10 05 42.5 ~19
Continuation to the ephemeris:
1977/78 ET R. A. (1950) Decl. Delta r m2
Dec. 3 2 07.30 -23 35.3 0.831 1.591 17.1
13 2 08.41 -20 33.7
23 2 13.81 -16 41.4 0.847 1.512 17.2
Jan. 2 2 23.41 -12 09.9
12 2 36.96 - 7 10.8 0.890 1.461 17.3
22 2 54.13 - 1 56.0
Feb. 1 3 14.54 + 3 21.8 0.961 1.442 17.5
11 3 37.86 + 8 30.4
21 4 03.79 +13 18.3 1.070 1.456 17.7
Mar. 3 4 31.92 +17 35.4
13 5 01.85 +21 14.3 1.221 1.503 18.1
23 5 33.08 +24 10.6
Apr. 2 6 05.02 +26 22.7 1.413 1.578 18.4
12 6 37.11 +27 51.6
22 7 08.81 +28 40.4 1.642 1.674 18.8
May 2 7 39.64 +28 53.8
12 8 09.30 +28 36.6 1.899 1.787 19.1
22 8 37.59 +27 54.5
June 1 9 04.41 +26 52.2 2.176 1.910 19.4
11 9 29.80 +25 34.2
21 9 53.81 +24 04.6 2.462 2.040 19.7
July 1 10 16.54 +22 26.5
11 10 38.13 +20 42.7 2.747 2.175 20.0
21 10 58.69 +18 55.6
31 11 18.35 +17 06.9 3.021 2.310 20.2
X-RAY BURSTS
F. Li and G. Clark, Massachusetts Institute of Technology, report
that they have observed with SAS 3 two very brief x-ray bursts
from a source in a 1.0-square-degree region that contains the variable
persistent source 4U 1746-37 in the globular cluster NGC 6441.
The bursts occurred on Aug. 4.761 and 5.404 UT, and both lasted
only about 3 seconds. Four more bursts from the globular cluster
NGC 1851, like the one previously reported (IAUC 3092), were observed
during the period July 26.0-27.8 UT. The apparent interval
between these bursts was 6.0 hours.
LMC X-4
N. E. White and P. J. Davison, Mullard Space Science Laboratory,
report: "Ariel 5 observations during July 15-23 reveal LMC
X-4 to eclipse for 0.206 +/- 0.008 day every 1.413 +/- 0.007 days;
mid-eclipse occurred on July 18.114 +/- 0.004 UT. The coincidence of the
x-ray period and phase with the optical values (IAUC 3073) confirms
the Sanduleak-Philip identification (IAUC 3023, 3039)."
CIRCINUS X-1
I. S. Glass, South African Astronomical Observatory, reports
that JHKL observations of the Mayo et al. candidate (IAUC 2957) suggest
a uniform decline in infrared brightness from x-ray phase 0 to
phase 1, using the ephemeris of Kaluzienski et al. (1976, Astrophys.
J. 208, L71). The range is about 1.5 magnitudes at K.
AM HERCULIS
R. F. Jameson, Leicester University, reports that on July 9
and 10 lightcurves of AM Her at 1.2 and 2.2 um were measured with
the 150-cm Tenerife telescope. The magnitudes at maximum are J =
11.15 and K = 10.55. The eclipse depths at J are 0.49 magnitude
(primary) and 0.39 magnitude (secondary). At K the primary eclipse
vanishes, but the secondary still has a depth of 0.60 magnitude.
COMETARY NEBULA NEAR NGC 7023
M. Cohen, L. V. Kuhi and E. A. Harlan, University of California
at Berkeley, write: "This object (R.A. = 20h45m25s.0, Decl. = +67o46'44"
equinox 1950.0; the coordinates were given incorrectly in Cohen et
al. 1977, Astrophys. J. 215, L127) has continued to brighten. Recent
V magnitudes are: 1976 Dec. 1, 16.9; 1977 June 17, 16.4; July
12, 15.5. The fan nebula has brightened and changed its structure.
Spectrograms covering 3300-8600 A show that the Fe II emission-line
spectrum is increasing in contrast to the continuum, and higher-member
Balmer lines are in absorption. On July 25 Calvet and Cohen
measured infrared magnitudes J = 13.1, H = 11.5, K = 10.3, L = 8.5.
It is possible that the object is an FU Ori star caught during its
rise. If so, it is extremely important to have complete and frequent
spectral cioverage, especially in the infrared and radio."
1977 August 18 (3095) Brian G. Marsden
Read IAUC 3096
Our Web policy. Index to the CBAT/MPC/ICQ pages.
