VSM 186 : 2008 October 3.
=========================
Object : 1309-67 ..... Muscae Posn: (2000) 13:16:36.44
-67:36:47.8 (P. Nelson)
Type : Possible nova. Confirmation required.
The initial announcement by discoverer Bill Liller is
reproduced here.
--> There seems to be a nova at 13h16m30s -67d37.0'
(2000).
-->A pair of photos taken on Sept 28, 2008, at 23:57 UT
(TechPan + orange filter with 85mm lens) shows a star there at
approximate magnitude 8.6. Nothing was seen brighter than
magnitude 11.5 at that position on Sept 15 at 0:33 UT or at any
earlier time in my survey.
Confirmation observations have been posted by Peter Williams
and Peter Nelson.
A 'd' scale chart is attached. The faintest star in the
sequence, 137v, is approximate. The ASAS-3 value differs
slightly, but is rather noisy.
The full sequence will be uploaded to AAVSO.
From CBET 1496
POSSIBLE NOVA IN SCORPIUS
S. Nakano, Sumoto, Japan, reports the discovery by K. Nishiyama
(Kurume, Fukuoka-ken) and F. Kabashima (Miyaki-cho, Saga-ken)
of a bright star (mag 9.5) on unfiltered CCD images obtained on
Sept. 2.4594 UT with a 0.40-m f/9.8 reflector, brightening to
mag 9.0 on Sept. 3.5119, the variable being located at R.A. =
17h57m32s.94, Decl. = -30o43'10".0 (equinox 2000.0). Nothing is
visible at this position on their unfiltered CCD frames taken
on Aug. 20.476 (limiting mag 12.8) and 21.470 (limiting
magnitude 12.1) using a patrol camera (+ 105-mm-f.l. f/5.6
lens). They note nearby USNO-B1.0-catalogue stars at position
end figures 33s.221, 10".56 (red mag 12.7) and 33s.015, 10".39
(red mag 14.8). Nakano also reports the independent discovery
of this variable by Yukio Sakurai (Mito, Ibaraki-ken) at mag
9.7 on two survey frames taken on Sept. 3.437 and 3.438 using a
Fuji FinePix S2 Digital Camera (+ Nikon 180-mm-f.l. f/2.8
lens), providing position end figures 33s, 09"; Sakurai adds
that nothing is visible at this position on a frame taken on
July 30 (limiting magnitude 12).
Guoyou Sun, Qufu, Shandong, China; and Xing Gao, Urumqi,
Xinjiang, China, report the independent discovery of this
possible nova (mag approximately 10.5) on several 60-s survey
images (limiting mag about 13.5) taken by Gao in the course of
the Xingming Observatory Nova Survey around Sept. 2.6095 and
2.6303 UT using a Canon EOS 350D Camera (+ 135-mm-f.l. f/2
lens, at ISO 400), the new object being approximately located
at R.A. = 17h57m32s, Decl.= -30o43'04" (equinox 2000.0).
Nothing was visible at this position on images taken on Aug.
14, 20, 21, 30, and 31 (limiting mag presumed to be about
13.5).
Following posting on the CBAT unconfirmed-objects webpage,
several other observers have sent observations of this apparent
nova. Unfiltered CCD 300-s images (limiting mag 14.5) taken by
D. Chekhovich, S. Korotkiy, and T. Kryachko with a Canon EOS
350D camera (+ 135-mm-f.l. f/4 lens) at Kazan State
University's Astrotel Observatory (Karachay-Cherkessia, Russia)
show the variable at mag 10.5 on Sept. 2.735 UT and mag 9.5 on
Sept. 3.732. Nothing is visible at this position on images
obtained on Aug. 30.783 (limiting mag 14.5). Astrometry
obtained by the same observers from 10-s CCD images obtained on
Sept. 3.72 with a 8.0-cm f/7.5 ED refractor (+ SBIG ST-2000XM
camera) yields position end figures 32s.91, 10".3.
E. Guido, G. Sostero, and P. Camilleri write that they observed
this object remotely with a 0.1-m f/5 refractor at Moorook,
Australia, on Sept. 3.45 UT, finding the object at unfiltered
CCD mag about 9.6 and at position end figures 32s.93, 10".3.
Nothing is visible on a U.K. Schmidt plate from 1992 June 3 (no
limiting magnitude provided), though a nearby field star with
position end figures 32s.95, 08".1 has magnitude about 18.
Their CCD image is posted at the following website URL:
http://tinyurl.com/5w5e8u.
C. Jacques and E. Pimentel, Belo Horizonte, Brazil, report that
their 30-s unfiltered CCD image on Sept. 3.96 UT with a 30-cm
f/3.0 Schimdt- Cassegrain reflector at CEAMIG-REA Observatory
yields mag 8.5 and position end figures 32s.83, 11".7. Nothing
is visible at this position on a Palomar Sky Survey image from
1958 Apr. 18 (limiting mag 19.0).
VSM 183 : 2008 September 4.
===========================
Object : 1751-30 ..... Scorpii
Position: (2000) 17:57:32.93 -30:43:10.3
Type : Possible Nova
Magnitude : 9.6C
Originally placed on the CBAT Unconfirmed Objects page, it has
now been confirmed by imaging, and precise position reported by
at least two other teams, eg E.Guido, G. Sostero and P.
Camilleri (Sept. 3.45) and S. Korotkiy (Russia). Still awaiting
final confirmation as a genuine nova.
Sequence:
=========
A V sequence is shown on the attached chart. The "nova" has two
close companions to the west, at ~12.5 mag. Take care when the
object fades. Star '138' is approximate as the ASAS3 photometry
is dependent on relatively few measurements, only about
50.
From CBET 1497
POSSIBLE NOVA IN CENTAURUS
G. Pojmanski, D. Szczygiel, and B. Pilecki, Warsaw University
Astronomical Observatory, report the discovery of a possible
nova on 3-min CCD images obtained with the ASAS-3V instrument
of the All Sky Automated Survey (200-mm-f.l. 70-mm-aperture
f/2.8 telephoto lens + Johnsons V filter; pixel size 14".8).
The position of the variable is given as R.A. = 14h35m03s,
Decl. = -64o06'.4 (equinox 2000.0); there are several faint
stars within 1 pixel of this position in the USNO-B1 catalogue.
ASAS-3V magnitudes for the possible nova: Aug. 24.070 UT, not
seen; 26.045, 9.97; 26.056, 9.93; 29.060, 8.40; 30.040, 8.38;
Sept. 1.015, 8.53.
G. Sostero, E. Guido, and P. Camilleri obtained "LBVRI" CCD
images during Sept. 2.4-2.5 UT remotely with a 0.3-m f/6
reflector at Trunkey, NSW, Australia, yielding position end
figures 02s.54, 20".0 and the following magnitudes (uncertainty
about 0.05 mag) for the variable: Sept. 2.39, B = 9.54, V =
8.63, R = 8.03, I = 7.42; Sept. 2.46, B = 9.69, V = 8.70, R =
8.10, I = 7.60. Comparison with a Palomar Sky Survey plate from
1991 July 17 (limiting red mag around 20) and an infrared plate
from 1981 Mar. 2 shows the presence near position of an
extremely faint optical counterpart (position end figures
02s.46, 20".2 and mag about 19.5) at the detection limit of the
plates; the star field is extremely crowded, and limiting
magnitude is difficult to establish. Sostero et al. have posted
an image of the possible nova at the following website URL:
http://tinyurl.com/5mcxrs.
Additional magnitudes for the possible nova, visual unless
otherwise noted: Aug. 23.994, [12.2 (W. Liller, Vina del Mar,
Chile, Tech Pan film + orange filter); Sept. 2.48, 8.4 (P.
Camilleri, Hurstville, NSW, Australia); 2.891, 8.3 (J. G. de S.
Aguiar, Campinas, Brazil); 2.938, 8.5 (W. Souza, Sao Paulo,
Brazil); 3.890, 9.2 (Aguiar).
