This
Astrobin Debut Object is a galaxy group of 6 galaxies, called Hickson 43, located in the constellation of Sextans at a declination of 0 degrees. 4 of the 6 galaxies are spirals.
5 of these 6 galaxies are close together, ranging from 450 to 470 million light years away. I see some deformation and asymmetry in the galaxies, so some of them may be interacting with each other.
The 6th galaxy, Hickson 43f, is much farther away at 0.9 billion light years. A 7th galaxy, just above 43f, is also 0.9 billion light years away but was not included in the cluster because it is a bit too far from the cluster center to be included using the Hickson isolation criteria.
The brightest galaxy, by definition 43a, is a magnitude 14 spiral galaxy with a double ring structure and a slightly warped disk.
The largest and most interesting galaxy, 43b, is a grand design spiral galaxy which spans 0.8 arc-minutes. This corresponds to a Milky Way like diameter of 120,000 light years. The disk of this galaxy also looks a bit warped.
The Hickson catalog is a collection of 100 galaxy groups, established by Paul Hickson in 1982. Hickson compact galaxy groups are strictly defined by 3 criteria: number of galaxies, total magnitude, and isolation from other galaxies. A typical Hickson group has 4 galaxies, but some have up to 8. You can see more about Hickson galaxy groups in my
Astrobin Hickson Collection.
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