This astrophotograph is of the spiral galaxy IC 342, also known as the Hidden Galaxy. It lies in the large but faint constellation of Camelopardalis (the giraffe) and is about 10.7 million light years away from Earth.
IC 342 was a ridiculous choice of targets given its extreme faintness and the 95% illuminated moon which just washes the sky out. I would not have bothered getting the telescope out if it weren’t for the fact that the last clear night was almost a full month ago on 19 September and I was desperate. I gathered light data for almost 1.5 hours until the moon really got too high.
IC 342 lies in the plane of the Milky Way and so it is heavily obscured by the stars, gas and dust clouds of our own galaxy; hence it being called the Hidden Galaxy. Because of this, and despite it actually being quite bright in reality, there was no clue of its existence when taking single frames with my astrophotography camera. I really had to stretch this image a lot and so it’s noisy, heavily-smoothed, and lacks detail like dust lanes.
Nevertheless, after a lot of painstaking processing, its core, winding spiral arms, blue(ish) star clusters, and pink(ish) star-forming regions began to lift out of the background. Towards the center, the stars tend to be older, and as you progress outwards the stars get younger with the blue regions in the spiral arms being denser pockets of gas where new stars are being formed. It appears to us face-on—IC 342 therefore makes a key target for observations of star formation and astrochemistry.
Frames
- 67× 130-s light frames
- 32× flat frames
- 30× dark flat frames
- Dark frames and bias frames from 8 September 2019
Equipment
- Explore Scientific ED 102 mm Apo f/7 refractor
- Sky-Watcher EQ5 PRO SynScan GOTO equatorial mount
- Altair GPCAM3 290C colour camera (with UVIR window fitted)
- Altair 60mm guide scope
- Altair GPCAM2 AR0130 mono guide camera
Software
- Sharpcap
- PHD2
- DeepSkyStacker
- Photoshop