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Alert! Nova Cas 2021 mag 9

PostPosted: Fri Mar 19, 2021 11:52 am
by Robin Leadbeater
From:
https://britastro.org/node/2581


Yuji Nakamura (Kameyama, Mie, Japan) has reported the discovery of a possible nova, PNV J23244760+6111140, on March 18.4236

Tonny Vanmunster confirmed the transient later that day at V = 8.95 +/- 0.03 (CBA Extremadura Observatory using a 0.40-m f/5.1 telescope and SX-46 CCD camera)

ATel #14471 reports spectroscopic classification of the object as a classical nova (Hiroyuki Maehara (National Astronomical Observatory of Japan), Kenta Taguchi (Kyoto University), Yusuke Tampo (Kyoto University), Naoto Kojiguchi (Kyoto University), Keisuke Isogai (Kyoto University).

Nova Cas 2021 is at RA 23 24 47.73 Dec +61 11 14.8 (J2000.0)

Re: Alert! Nova Cas 2021 mag 9

PostPosted: Fri Mar 19, 2021 12:57 pm
by Francois Teyssier
Thank you Patrick, Robin, for the alert.

The page is ready for the spectra.
Probably the last one in the old database format before the tranfer of novae section to the new online database.
http://www.astrosurf.com/aras/Aras_DataBase/Novae/2021_NovaCas2021.htm

Please use "Nova Cas 2021" as OBJNAME.

I wish you clear skies.
Blue sky here ...

François Teyssier

Re: Alert! Nova Cas 2021 mag 9

PostPosted: Fri Mar 19, 2021 10:54 pm
by David Boyd
This spectrum of Nova Cas 2021 was recorded with a LISA spectrograph on a C11 during a short break in generally overcast skies tonight. It shows strong emission lines of the hydrogen Balmer series and He I. There are P Cygni profiles extending to around -2500 km/s relative to the rest wavelength on all emission lines. The spectrum was calibrated in absolute flux using currently recorded B and V photometry which gave V = 7.77+-0.04 and B-V = 0.50.

David

Nova Cas 2021 19 Mar 21.png
Nova Cas 2021 19 Mar 21.png (31.1 KiB) Viewed 2066 times

Re: Alert! Nova Cas 2021 mag 9

PostPosted: Sat Mar 20, 2021 7:38 am
by Francois Teyssier
Hi David,
Well done!



François

Re: Alert! Nova Cas 2021 mag 9

PostPosted: Sat Mar 20, 2021 11:26 am
by Pascal Le Du
Hello

My small contribution for this very interesting Nova.
Spectrum realized from the tip of Brittany with a 200 mm newton and an Alpy600 (7x30sec).
FenteNovaCas2021.jpg
Fente sur cible
FenteNovaCas2021.jpg (161.28 KiB) Viewed 2007 times

NovaCas2021.jpg
NovaCas2021.jpg (44.47 KiB) Viewed 2012 times

For information, it is better to make the spectrum of this nova with a vertical slit.
Indeed, as we can see on the PanSTARRS image and on my spectrum which compiles 29 exposures of 30 seconds, the stars located near the nova can pollute its spectrum.
NovaCas2021_PanSTARRS_DR1.jpg
PanSTARRS DR2
NovaCas2021_PanSTARRS_DR1.jpg (130.83 KiB) Viewed 1987 times

NovaCas2021_29x30sec.jpg
NovaCas2021 29x30 sec
NovaCas2021_29x30sec.jpg (34.63 KiB) Viewed 1987 times


Pascal

Re: Alert! Nova Cas 2021 mag 9

PostPosted: Sat Mar 20, 2021 7:35 pm
by Matthieu Le Lain
Hi all,

A new spectrum of NovaCas2021 with an Alpy600 last night, on C8 f/6.3 - Atik460Ex - 10 x 90s exp.

NovaCas2021_20210320_076_ml.png


NovaCas2021_20210320015823_lines.png
NovaCas2021_20210320015823_lines.png (42.34 KiB) Viewed 1947 times


Matthieu

Re: Alert! Nova Cas 2021 mag 9

PostPosted: Sat Mar 20, 2021 9:42 pm
by Olivier GARDE
And my contribution with this spectrum taken with an eshel spectrograph (R=11000) with difficulty because I had a tree that was in the line of the sight of the nova !!! and very low in my north west horizon), so only 6 exposures of 600s each.

Here's the full spectrum (I cut the spectrum at 4300 Å because the blue part is very noisy).

Image

And the quick calculation of the ejecta velocity on H Alpha and H beta line

Image


The Helium I 5875 emission line, always with p Cyg profil

Image

Re: Alert! Nova Cas 2021 mag 9

PostPosted: Sun Mar 21, 2021 7:08 am
by Christophe Boussin
Hello all,

Here is my contribution to the monitoring of the nova Cas 2021.
The following spectrum was obtained the 20th of March at 19 h 42 TU with my Alpy 600 (resolution of 528, JJ = 2459294.3211) and an acquisition time of 25 min (5 x 300s) :

Champ NOVA CAS 2021.png
Guiding camera field
Champ NOVA CAS 2021.png (183.43 KiB) Viewed 1860 times


_novacas2021_20210320_821_Christophe Boussin_3550_7400.png
Nova Cas 2021 on March 20th, 2021
_novacas2021_20210320_821_Christophe Boussin_3550_7400.png (99.45 KiB) Viewed 1860 times


novacas2021_20210320_821_Christophe Boussin.png
Nova Cas 2021 on March 20th, 2021 (identification of some lines from PlotSpectra)


Clear skies,

Christophe BOUSSIN

Re: Alert! Nova Cas 2021 mag 9

PostPosted: Sun Mar 21, 2021 9:24 am
by Joan Guarro Flo
Hello at all,

This is Nova Cas 2021 last night from RSMM.

Cheers, J. Guarro.

Re: Alert! Nova Cas 2021 mag 9

PostPosted: Sun Mar 21, 2021 10:46 am
by Francois Teyssier
Excellent team!

Light curve (BVR) from AAVSO: