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Cosmic scales


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About this observation
Kevin Gurney
Time of observation
30/09/2017 - 01:30
Arp 284
Observing location
West Sheffield
Celestron 8SE, OAG, 0.77 flat/reducer
Atik 460EX mono, SX guide cam
Skywatcher AZ-EQ6-GT
Baader filters (L, R, G, B)
15 Lum subs, 9 each of R,G,B al lbin 1x1, 5mins (3.5 hrs total)

I became aware of this composition in a recent article in Sky and Telescope, and decided to try and capture it in my backyard. It shows a conjunction of objects at three different cosmic scales...

In the foreground is the star 16 Pisces; at magnitude 5.7 this is visible by the naked eye and overshadows everything in this deep sky image - processing it away selectively was a challenge! This star is a mere 100 light years away.

Nearby in the image are the two interacting galaxies, NGC 7714 and 7715, collectively know as Arp 284. The peculiar shapes are evidence of strong intergalactic forces. These galaxies are around 100 million light years away.

To the right and slightly below Arp 284 (see small label) is a small blueish 'star' that is actually a quasar (QSO B2333+019) 10 billion light years away! (z = 1.87).

The night was quite windy and so guiding was not as good as it might be; some more detail could be revealed on a better night perhaps.

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