Central Bureau for Astronomical Telegrams
IAUC 4501: N Vul 1987; 1987p
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 4502
Circular No. 4501
Central Bureau for Astronomical Telegrams
INTERNATIONAL ASTRONOMICAL UNION
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
NOVA VULPECULAE 1987
J. Gallagher reports several observations of Nova Vulpeculae
1987 obtained at Lowell Observatory. Photometric observations by
B. Skiff with the 0.5-m telescope using Stromgren vby filters
relative to the four-color standard star HR 7253 give the following:
Nov. 20.07 UT, 'V' = 7.22, b-y = +0.610, v-b = +0.522; 22.06, 'V'
= 7.33, b-y = +0.548, v-b = +0.447; 24.07, 'V' = 7.21, b-y = +0.544,
v-b = +0.443; 25.07, 'V' = 7.64, b-y = 0.575, v-b = +0.471.
Spectrophotometric observations by R. M. Wagner, Ohio State University,
with the OSU IDS on the OWU-OSU Perkins 1.8-m telescope on Nov.
23.1 and 25.1 UT show strong Balmer, Fe II, Na I, Ca II and O I
emission lines and a reddened continuum. Strong P-Cyg profiles
are seen in the O I 777.4 nm, Na I D and Ca II H and K lines. The
H alpha-emission FWHM width is 920 km/s, and the O I 777.4-nm P-Cyg
velocity is 930 km/s. The spectra and colors are consistent with
a moderately reddened, normal classical nova in the early decline
stage. Substantial night-to-night variability found by Skiff is
suggestive of a medium-speed-class, rapidly-fluctuating lightcurve
of the DK-Lac type. Dense photometric coverage may be particularly
useful for this nova.
S. G. Starrfield, Arizona State University; and G. Sonneborn,
IUE Observatory, report IUE observations on Nov. 23 and 25 UT.
During this time the ultraviolet flux decreased by a factor of
two. The continuum is very red and weak emission is present.
R. D. Gehrz, Department of Astronomy, provides the following
position, obtained using the encoders on the Wyoming 2.3-m Infrared
Telescope: R.A. = 19h02m32s.26, Decl. = +21 41'39".9 (equinox 1950.0).
He also communicates the following infrared photometry by T. Harrison
and J. Johnson at the O'Brien Observatory on Nov. 20.0 UT: R
= 6.2, I = 5.4, J = 5.3, H = 5.0, K = 4.6, L = 4.5, M = 4.1.
Photoelectric photometry by R. Zissell, Williston Observatory,
Mt. Holyoke College: Nov. 22.97 UT, V = 7.38, B-V = +0.64.
The second comparison star (IAUC 4489) should read 113 Her.
PERIODIC COMET BORRELLY (1987p)
Total visual magnitude estimates by R. A. Keen, Mt. Thorodin,
CO: Nov. 20.25 UT, 8.2 (20 x 120 binoculars); 22.33, 7.7 (8 x 40
binoculars); 25.22, 8.0 (0.32-m reflector; 8' coma).
1987 November 26 (4501) Brian G. Marsden
Read IAUC 4502
Our Web policy. Index to the CBAT/MPC/ICQ pages.
