the ngc 6946 Galaxy and the
sn 2017eaw supernova (Robotic)

Main Objects: ngc 6946, sn 2017eaw

The fading of SN 2017eaw supernova through the robotic scope

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gallery/ngc6946_terkep
gallery/ngc6946_2400_annotateds

My first serious robotic telescope attempt was to capture the fading SN 2017eaw. I've already photographed this celestial body, so I got the pleasure of capturing it with a professional equipment.
 

A little reminder of my photograph of August 2017: "Let's start: SN 1917A, SN 1939C, SN 1948B, SN 1968D, SN 1969P, SN 1980K, SN 2002hh, SN 2004et, SN 2008S and SN 2017eaw. Long, almost endless listing. Each of them is the name of a supernova, which was detected in the galaxy NGC 6946 in the past 100 years. The galaxy (with an apparent magnitude of 9.6) is located at the edge of the Cepheus and Cygnus constellations. The galaxy received its name ("Fireworks”) from the frequent supernova-explosions.

The supernova SN 2017eaw was detected on May 14, 2017 in the Fireworks Galaxy (NGC 6946), 22 million light-years away. At its discovery, its apparent magnitude was 12.8; at the time when the photograph was taken, this value was around 13.1. This means that it has barely faded over three months."


During my robotic session, it already faded around 15.0, but the supernova was still well identified. In spite of the relatively low exposure time, a spectacular photo was made with the new Mexican T21 telescope. It was also my first astrophoto, where I had to process color-filtered images and "luminance" images.
 

With the post-processing of the galaxy, as well as the August capturing, I was in trouble with the correct adjustment of the sharpness, as the light of the galaxy comes from behind a cosmic cloud of dust, thus producing "filtered" photons in color and sharpness that make this beautiful spiral galaxy even more special.

Name:

Fireworks Galaxy, NGC 6946, C12, SN 2017eaw

Constellation:

Cepheus, Cygnus

Coordinates:

R.A. 20 h 34 m 52 s Dec. +60° 09′ 13″

Type:

Barred spiral galaxy - SBc

Distance:

22.5 ± 7.8 million light-years

Brightness:

9.6m

Apparent size:

11' 30" x 09' 48"

Size:

40,000 light-years

Observable: 

Spring, summer, autumn

Date:

25/09/2017

Total exposure time:

36 minutes

Location:

iTelescope - T21, New Mexico, USA

Camera:

FLI-PL6303E

Telescope:

Corrected Dall-Kirkham Astrograph 431/1940 mm

Mount:

Planewave Ascension 200HR

Guiding:

Autoguiding

Corrector:

0.66x reductor

Focal ratio, length:

f/4.5, 1280 mm

ISO:

-

Light:

3 x 180 s Red, 3 x 180 s Green, 3 x 180 s Blue, 3 x 180 s Lum

Dark:

Calibrated

Flat:

Calibrated

Bias:

Calibrated

Processing:

PixInsight, Adobe Lightroom, Adobe Photoshop

Location

Annotation