HGC 61 was first discovered by William Herchel in April of 1785. In 1981, Paul Hickson added it to his list of compact galaxy groups, and it became known as HCG 61. Hickson’s criteria was at least 4 galaxies in a compact group. He did understand that without a distance estimate to the galaxies that it couldn’t be determined if the group was truly a group or apparently grouped from our perspective, as is the case here.
The group consists of 4 galaxies:
NGC 4169: A Seyfert 2 Galaxy; distance of 58.0 Mpc (189 Million light years based on redshift)
NGC 4170 (sometimes NGC 4173): A low surface brightness galaxy, edge on which makes exact type classification difficult. A distance around 11-13 Mpc (35-42 Mly)
NGC 4174: A Seyfert 2 Galaxy; at a distance of 60.0 Mpc (195 Mly based on redshift)
NGC 4175: An edge on spiral galaxy with an active nucleus; at a distance of 60.0 Mpc (195 Mly based on redshift)
Clearly from the above data, NGC 4170 is not a true part of the galaxy group, but it is likely that the other three are at least local group members, although there is no evidence they are interacting. Nearby 4174 is LEDA (PGC) 213947, another only apparently close galaxy, as its redshift distance puts it at over 1Bly away.
Technical Card
Mount: Celestron AVX
Camera(s): ZWO ASI 2600mc pro, ZWO ASI 220 mini guide camera on an OAG
OTA: Celestron C8 SCT with 6.3 reducer
Filters: None
Exposure: 135 Lights @ 180 seconds
Annotated image:
Here’s the wider field view with some of the larger of the faint galaxies identified.
Sweetman Astrophotography 
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