NGC 2857 (Arp 1)  +  Arp 285

Full resolution (1600x1200 px  350kB)

150% resolution (600kB)

Object identification (350kB)

Inverted image showing the tidal tails of Arp285 (250kB)

Object data of NGC2857 (Arp1)

Object type: galaxy (Sc)
Size: 2.2'
Magnitude: 13.2 mag
Constellation: UMa
Distance: 220 Mio Ly

The face on spiral galaxy NGC2857 is the first entry in the Arp catalogue. It's Arp class is "spiral galaxies with low surface brightness". NGC2857 shows two very long thin spiral arms, as can be seen clearly in the above image.

Object data of Arp285 (NGC2854 + NGC2856)

Object type: galaxy pair
Size: NGC2854: 1.6'  /  NGC2856: 1.1' 
Magnitude: NGC2854: 13.8mag  /  NGC2856: 14.0 mag
Constellation: UMa
Distance: 130 Mio Ly
Notes: The galaxy pair Arp285 is a member of the Arp class "double galaxies, infall and attraction". The huge tidal arms, which are very well visible in the inverted image, are a clear sign for the interaction between these galaxies.

The above image shows on the left side also a nice group of galaxies in a distance of 370 Mio light years. UGC5016, CGCG 238-053 and CGCG 238-054 are brighter members of this galaxy group.

Exposure data

Date: 2010-04-02 + 06 + 07
Location: Nussbach / Austria (400m)
Telescope: 12" Newtonian telescope (f=1120mm)
Camera: ST2000XM with CFW8 and Baader Filters
Binning: L 1x1 / RGB 2x2
Exposure time: L 28x12m / R 11x8m / G 11x8m / B 11x8m
Exposure time total: 10h 00m