Probable nova in Hercules mag 6.4 !

[Robin Leadbeater]

From VSNet

Cheers
Robin

-----Original Message-----
From: vsnet-alert <vsnet-alert-bounces@ooruri.kusastro.kyoto-u.ac.jp> On Behalf Of Patrick Schmeer pasc1312-aavso@yahoo.de via vsnet-alert
Sent: 12 June 2021 17:09
To: vsnet-alert@ooruri.kusastro.kyoto-u.ac.jp; vsnet-newvar@ooruri.kusastro.kyoto-u.ac.jp; cvnet-outburst@groups.io; baavss-alert@groups.io
Subject: [vsnet-alert 25957] TCP J18573095+1653396: bright probable nova (mag. 6.4) in Hercules

TCP J18573095+1653396 = ZTF19aasfsjq (N:) (submitted to VSX)

Discovered on 2021 June 12.537 UT at mag. 8.4 by Seiji Ueda (Kushiro, Hokkaido, Japan):
http://www.cbat.eps.harvard.edu/unconf/ ... 53396.html

ZTF light curve, data, and images (via Lasair):
https://lasair.roe.ac.uk/object/ZTF19aasfsjq/

Possibly recorded on the rise (gmag. ~16.3 on June 12.192 UT) by the ASAS-SN Sky Patrol:
https://asas-sn.osu.edu/sky-patrol/coor ... 6b21100256

Source No. 4514092717838547584 in Gaia EDR3 (Gmag. 19.95).

Spectroscopy and multiband photometry are urgently required.

Clear skies,
Patrick

[David Boyd]

Here is a low resolution R~1000 spectrum of the new bright object in Her, now announced in ATel 14704 as a nova. Taken with a LISA on a 0.28m SCT. This has been instrument and atmospheric response corrected.
David

novaher2021_20210612_927_D_Boyd.png (34.24 KiB) Viewed 11554 times

[HughAllen]

And here is my Alpy spectrum of Nova Her 2021. I've not seen a spectrum like this before...

Nova Her 2021 2021.06.12.939.png (30.14 KiB) Viewed 11539 times

Cheers
Hugh

[Christophe Boussin]

Hello all,

Here is my spectrum of the Nova Her 2021 obtained the 13th of June at 1 h 01 TU (resolution of 531, JJ = 2459378.5425) with my Alpy 600 and an acquisition time of 30 min (6 x 300s) :

Nova Her 2021 on June 13th, 2021

_novaher2021_20210613_043_Christophe Boussin_3700_7565.png (111.45 KiB) Viewed 11532 times

Clear skies to all !!

Christophe BOUSSIN

[Francois Teyssier]

Very fast nova.
Impressive spectrum.
Rapid evolution of spectrum is expected.

Page created in the new database : https://aras-database.github.io/databas ... r2021.html

François Teyssier

[Joan Guarro Flo]

Hello,

That is the Nova Her 2021, from the NOU_T echelle from SMM.

Regards, J.Guarro.

[Stephane Charbonnel]

Hello,

A spectrum among the three taken yesterday during the night with my ESHEL from Shelyak :

Spectrum R=11'000

An image of the field (the object is in the hole and very bright) :

Le champ spectral

Champ_Spectral_Nova_Her.jpg (127.8 KiB) Viewed 11436 times

Must be followed.

Is it always a probably nova or are we sure it is a nova ?

Stéphane

[Robin Leadbeater]

Hello,

That is the Nova Her 2021, from the NOU_T echelle from SMM.

Regards, J.Guarro.

Beautiful !

[Francois Teyssier]

Is it always a probably nova or are we sure it is a nova ?

The spectrum is not usual. It looks like a supernova.
Very fast nova, fast velocity and probably fast evolution.
Thus, massive white dwarf.

A similar spectrum: Nova Sct 1991, probably taken a few days after the maximum (emission components stronger than in the spectra secured last night).

Sct1991.PNG (23.41 KiB) Viewed 11379 times

See also V1500 Cyg (Nova Cyg 1975)

Raw spectrum (ongoing acquisition)

NovaHer2021.PNG (131.58 KiB) Viewed 11379 times

Very broad Balmer emissions.

[David Boyd]

The spectrum tonight looks very different. It is now about 2 magnitudes fainter.

David

novaher2021_20210613_928_D_Boyd.png (19.49 KiB) Viewed 11372 times