THE ASTRONOMER Electronic Circular No 529       1991 June 8  9.06UT
Ed:Guy M Hurst, 16,Westminster Close, Kempshott Rise,  Basingstoke,
Hants, RG22 4PP, England. Telephone:  (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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3C 345
F.Makino in Japan has reported that X-ray observation with the
Ginga satellite of this quasar on 1991 May 25 shows the flux to
have doubled since 1989 Apr 27. We are asked to monitor this object
optically, which in fact is in accordance with earlier requests by
Dr.Mark Kidger in Tenerife (cf E494,495). The latest results from
Gary Poyner in Birmingham for May are:
May 1.97, [14.3; 5.96, [15.2; 9.03, [14.3; 11.98, [15.2; 14.96,
[14.3; 25.01, [14.3.
Please e-mail your results regularly even if negative. If anyone
requires a chart please e-mail me.

SUPERNOVA 1991ae IN MCG +11-19-018
J. Mueller reports her discovery of a supernova 2" west and 8"
north of the nucleus of the galaxy MCG +11-19-018 (R.A. = 15 48.4,
Decl. = +68 15, equinox 1950.0). The object was at B approx. 18 on
a plate taken on May 17 by C. Brewer, J. D. Mendenhall and herself
with the 1.2-m Oschin Telescope in the course of the Second Palomar
Sky Survey. A spectrum obtained by W. Sargent and M. Strauss with
the 5-m Hale Telescope (+ double spectrograph) on June 6 shows
strong H Alpha and H Beta emission and He I 587.6-nm emission,
indicating a peculiar type II supernova; the object was then at mag
approx. 17.
IAUC 5282

SUPERNOVA 1991af IN ANONYMOUS GALAXY
J. Mueller also reports her discovery, from a similar plate taken
on May 19, of a supernova in an anonymous galaxy at R.A. = 17 25.1,
Decl. = +29 31 (equinox 1950.0).  The SN is 6".7 east and 3".3
south of the centre of the galaxy and had B approx. 18.5 mag. A
June 6 spectrum obtained as above indicates that this is a type II
supernova.
IAUC 5282

PERIODIC COMET D'ARREST = COMET LA HIRE (1678)
Although the possibility of the identity of P/d'Arrest with a comet
observed by La Hire in 1678 was suggested shortly after its 1851
discovery (Valz 1851, Comptes Rend. No. 2, p. 155) and promptly
forgotten, this has recently been independently considered by A.
Carusi, and G. B. Valsecchi, Istituto Astrofisica Spaziale, Rome,
and L. Kresak and M. Kresakova, Slovak Astronomical Institute,
Bratislava, and proven to be correct. Although eight approaches
within 0.5 AU of Jupiter during the 26 revolutions 1678-1851
complicate the linkage, Carusi et al. have ascertained that the
nongravitational effects on the comet, while relatively large, seem
to be extraordinarily stable.
The following orbital elements established by them for the 1678
epoch satisfy three of La Hire's four observations within 0.2 deg:
T = 1678 Aug. 23.395 ET, Peri. = 159.377, Node = 168.939,
Incl. = 2.811 (equinox 1950.0), q = 1.16285 AU, e = 0.67008.
IAUC 5283

Guy M Hurst