Object of the Week October 20, 2013 – NGC 450/UGC 807 a discordant galaxy pair in Cet
NGC 450 / UGC 807
Cetus
RA: 01 15 30.4
DEC: -00 51 41
Size: 3’ x 2.4’
Mag NGC 450: 11.6v
Mag UGC 807: 15,7b
Discovered by F.W. Herschel in the year 1785 - NGC 450 seems to be a normal SAB(s)cd spiral in the sky. “Hand GoTo friendly” 12’ NE of the 5,7mag bright 38 Cet the galaxy should be visible even with a small 4” aperture telescope.
A second view shows a fainter companion at the NE edge – UGC 807. The different redshift and radial velocity numbers seems to show an unmistakable situation. While NGC 450 is calculated 64 Mio Lj, UGC is around 8 times more distant with 484 Mio Lj (NED). Rubin and Ford measured their rotational velocities 1983 and concluded that both galaxies are not physically associated.
Moles et all again studied the galaxy pair 1994 and conclude the opposite. Their studies showed that both galaxies interacting with each other.
Nevertheless the observation of these two “discordant” galaxies seems very interesting. With a brightness of 15,7bmag the fainter UGC should be visible as a faint spot from perhaps 12”-14” range? A 20” showed the UGC as a prominent companion with hints of elongation. The 27” showed the pair as a wonderful object – both galaxies bright and easy.
Aside from the companion NGC 450 sowed some bright HII regions at the eastern edge which should be in reach of a 16”-18” telescope.
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