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IAUC 4213: 1986H; NO SN IN NGC 5253; HERBIG-HARO 46

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                                                  Circular No. 4213
Central Bureau for Astronomical Telegrams
Postal Address: Central Bureau for Astronomical Telegrams
Smithsonian Astrophysical Observatory, Cambridge, MA 02138, U.S.A.
TWX 710-320-6842 ASTROGRAM CAM    Telephone 617-495-7244/7440/7444

     C. Pollas, CERGA, reports his discovery of a probable supernova
at R.A. = 14h28m10s6, Decl. = +7deg29'49" (equinox 1950.0).  The
object, located in NGC 5645, is of B ~ 17 and was found on a III-aJ
exposure by T. Laverge on May 11.94 UT, taken with the 0.9-m
Schmidt telescope at Caussols in the course of the International
Near-Earth Asteroid Survey.  Another exposure on May 12.87 UT
confirms an object not obviously present on the Palomar Sky Survey.

     A. V. Filippenko and P. J. McCarthy, University of California
at Berkeley, report that CCD images of NGC 5253 obtained with the
4-m reflector at Cerro Tololo on 1984 July 24 and with the Shane
3-m reflector at Lick Observatory on 1986 May 10 exhibit no
significant difference in the intensity ratio of H II regions A and C
(IAUC 4212).  Moreover, a spectrum (range 410-820 nm, resolution
11 nm) of H II region A, obtained with the Shane telescope on 1986
May 10.3 UT, also shows no evidence for the supernova (1986F)
announced on IAUC 4206.  Instead, extremely strong, narrow emission
lines having intensity ratios typical of relatively high-excitation
H II regions dominate the spectrum and are superposed on a
very blue continuum.  Faint emission lines of N III, C IV and He
II are visible near 465 nm; these are probably due to Wolf-Rayet
stars.  In addition, Fe II emission lines may also be present at
520 nm and elsewhere, but they are much weaker than in eta Car and
in RR Tel (Thackeray 1953, M.N.R.A.S. 113, 211).

     J. A. Graham, Department of Terrestrial Magnetism, Carnegie
Institute of Washington, reports: "Observations at Las Campanas
show a several-fold brightening in HH 46, which has substantially
changed its appearance and that of its surroundings since 1982-
1984 (cf. Graham and Elias 1983, Ap.J. 272, 615; Cohen et al. 1984,
Ap.J. 281, 250).  The change seems to be due, either to a flaring,
or to a partial clearing of the surrounding dust, the former being
the more probable.  Spectroscopic and infrared observations would
be extremely valuable for assessing the nature and significance of
the event in early stellar and planetary evolution."

1986 May 13                    (4213)              Brian G. Marsden

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