AT 2020nvb: possible supernova (13.1 mag) in NGC 4457

Affiliation
Association Francaise des Observateurs d'Etoiles Variables (AFOEV)
Wed, 07/01/2020 - 20:58

AT 2020nvb (SN:)

Discovered by Koichi Itagaki: https://wis-tns.weizmann.ac.il/object/2020nvb
CCD image at https://wis-tns.weizmann.ac.il/system/files/comment_files/2020nvb_0.jpg

This transient is confimed by recent ASAS-SN Sky Patrol (Shappee et al. 2014ApJ...788...48S and Kochanek et al. 2017PASP..129j4502K) data at https://asas-sn.osu.edu/light_curves/94fac18b-4c97-45af-8989-b5b38eaca7…
gmag. 13.1 (corrected) on 2020 July 1.260 UT.

Spectroscopy and multiband photometry are required.

Clear skies,
Patrick

Affiliation
American Association of Variable Star Observers (AAVSO)
AT 2020nvb Sequence

The sequence for AT 2020nvb is complete and in VSP.

F chart (18.5 arcminute)

Erik Schwendeman

AAVSO Sequence Team

 

Affiliation
American Association of Variable Star Observers (AAVSO)
SN 2020nvb - Alert Notice 709

AAVSO Alert Notice 709 reports on the discovery of the bright Type Ia supernova SN 2020nvb in NGC 4457 (Vir). Please see the notice for details and observing instructions.

Many thanks, and Good observing,

Elizabeth O. Waagen, AAVSO HQ

Affiliation
American Association of Variable Star Observers (AAVSO)
Question: isn't the supernova

Question: isn't the supernova really "close" to the galactic core and does that mean SN 2020nvb has to be observed at high magnification to separate it from the galactic core?

Also, is it possible to measure SN 2020 nvb and NGC 4457 together and extrapolate the supernova's brightness from initial brightness of the galaxy?

Affiliation
American Association of Variable Star Observers (AAVSO)
SN 2020nvb - Alert Notice 709

Hello! I gave it a try. Difficult target. I don't trust my analysis and deleted my observations. Best regards.

Mike

Affiliation
American Association of Variable Star Observers (AAVSO)
I took a second shot and was

I took a second shot and was able to barely get in one two-minute exposure in V and the other in B before the weather turned bad.  If anyone wants to look, I can send you the images I used.