Astro Gregas

Supernova impostor in NGC5194 ( M 51 )

Supernova impostor in NGC5194 ( M 51 )

Discovered by Zwicky Transient Facility (ZTF)" on 2019/01/22.555 as a transient suspected to be a supernova.

LBV's are a type of variable star. They are massive unstable supergiant and some are expected to evolve and end up as a Wolf-Rayet's

M 51 galaxy is situated in the Canes Venatici constellation, also known as NGC 5194.

My observation on Mars 10th was made using the following setup:

C14 @F6. , 0.35cm, 2135mm, 0.66"/px

KAF3200ME (SBIG ST-10XME) 6.78u

Paramount ME

Filter Astrodon Clear+NIr

9 images of 180s were median combined.

In the image below we can see the comp stars used in the ensemble photometry.

Magnitude values were extracted from Gaia DR2 G-band and excluded known variables.

As a note we can se a few previous supernovas in cyan in the top image.

Gaia DR2 filters response with G-band plot