AAVSO Alert Notice 412

Nova Sct 2009 (V496 Sct)
November 10, 2009

Event: Nova in Scutum (V496 Sct == N Sct 2009)

Discovered By: H. Nishimura (Miyawaki, Kakegawa, Japan)

Discovery Date: 2009 November 8.370 UT

Discovery Magnitude: unfiltered CCD magnitude of 8.8, using 120-mm 
camera lens, derived by S. Nakano (Sumoto, Japan) from Nishimura's
discovery images.

Position: RA: 18:43:45.57 , Dec: -7:36:42.0 (equinox 2000.0) from 
E. Guido and G. Sostero, using a 0.25-m reflector sited at Mayhill,
New Mexico, USA.

Spectra: A low-resolution spectrum was obtained by F. Teyssier using a
0.2-meter telescope equipped with a spectrograph having an effective
resolution of 8.56 Angstroms (4.28 Angstroms/pixel, 2-pixel bins).  This
spectrum clearly shows the presence of the H-alpha and H-beta lines,
both having P Cygni profiles.  Several weaker emission lines are also
present. D. Balam (NRCC) and G. Sarty (U. Sask.) obtained a spectrum
covering the wavelength range of 429-455 nanometers on 2009 November
10.08 UT confirming the presence of several emission lines having P
Cygni profiles. U. Munari et al. (INA-Padova & the Asiago Novae and
Symbiotic Stars Collaboration) report a low-resolution spectrum (0.21
nm/pix) obtained on 2009 November 9.779 UT with a 0.6-meter telescope. 
The spectrum contains multiple emission lines including the H-Balmer
series, OI, and FeII, all with P Cygni profiles.  The presence of FeII
lines indicates a nova of the Fe II-type.

Observations Reported to the AAVSO: 2009 Nov 9.0932 (JD 2455144.5932),
R=7.76 (V. Mechinsky, Minsk, Belarus); Nov 9.7549 (2455145.2549),
m(vis)=8.4 (S. Shaffer, Laramie, Wyoming, USA); Nov 9.8717
(2455145.3717), CV=8.61 (C. Spratt, Victoria, B.C., Canada); Nov 10.0506
(2455145.5506), V=8.04 (S. Howerton, Arkansas City, Kansas, USA); Nov
10.0625 (2455145.5625), m(vis)=8.4 (S. Aguirre, Hermosillo, Sonora,
Mexico).

Charts: Finder charts for V496 Sct may be plotted by entering the
coordinates above into VSP: http://www.aavso.org/observing/charts/vsp/

Reporting Observations: Please report all observations to the AAVSO as
"V496 Sct".  The names "Nova Sct 2009" or "VSX J184345.5-073642" are
equivalent, but the GCVS name is preferred.

Notes:

a. The object was initially announced in CBET #2008 (D.W.E. Green,
editor), where the discoverer notes that no object was visible on an
image taken on 2009 November 7.377 using the same camera, with a
limiting magnitude of 11.5 (unfiltered).

b. E. Guido and G. Sostero reported their confirmation and improved
position in CBET #2008, with images taken with the GRAS 0.25-m telescope
sited near Mayhill, NM on 2009 November 9.08. Guido and Sostero also
note that no unambiguous progenitor appears on a red DSS plate taken on
1996 August 13.

c. F. Teyssier (Rouen, France) kindly provided a spectrum of the object
taken on 2009 November 9.729 indicating the presence of Hydrogen and
other emission lines with P Cygni profiles.  An image of this spectrum
may be obtained from the following website:

        http://www.astronomie-amateur.fr/Projets%20Spectro4%20Novae.html

d. Information on name assignment and spectroscopic information used in
this Alert Notice were taken from IAU Circular #9093 (D.W.E. Green,
editor). This Alert Notice supersedes AAVSO Special Notice #176 (2009
November 9).


Congratulations to H. Nishimura for his discovery!

Good observing,

Matthew Templeton, AAVSO