Hickson 44 galaxy group

This image is based on data from Astrophotomarket.com from 2025 and shows the compact galaxy group Hickson 44. The group consists of the four principal members NGC 3185, NGC 3187, NGC 3190, and NGC 3193, located in the constellation Leo.

Hickson 44 is a classic example of a compact galaxy group, where several galaxies are bound together in a relatively small volume of space, leading to strong gravitational interactions. The group lies at a distance of roughly 80–100 million light-years. Three of its members—NGC 3185, NGC 3187, and NGC 3190—are spiral galaxies showing clear signs of tidal distortion. NGC 3190, in particular, is notable for its prominent dust lane and warped disk, likely the result of past or ongoing gravitational encounters. NGC 3187 appears visibly distorted, with stretched spiral arms that betray the dynamical forces at work. In contrast, NGC 3193 is an elliptical galaxy, probably residing near the gravitational center of the group.

Compact groups like Hickson 44 are important laboratories for studying galaxy interaction, tidal stripping, and the role of environment in galactic evolution. Deep imaging can reveal faint tidal tails and diffuse intragroup light—evidence of stars that have been gravitationally stripped from their host galaxies during close encounters.

Data calibration, registration and the final processing was done with PixInsight. The result was as follows:

The image also contains a remarkable number of quasars, emphasizing the extreme depth of the dataset. Among them, I have highlighted those with a redshift z > 3, meaning their light has traveled for more than 11 billion years before reaching us. At these redshifts, we are observing the universe when it was less than 2 billion years old.

The 2 most distant of them are:

• WISEA J101719.93+204826.6 with a redshift of 4.8
• WISEA J102106.26+223234.9 with a redshift of 4.4

The images were taken with the following equipment:

• Date: 2025
• Location: Astrophtomarket, Poland
• Telescope: Skywatcher Esprit 120mm
• Focal length [mm]: 636
• Focal ratio: 5.25
• Mount: ZWO AM3
• Camera: ZWO ASI 2600MM Pro
• Filter: L:R:G:B
• Exposure time [min]: 550:70:70:70
• Resolution: 1.12″/px