The handful of low-mass , late-type galaxies that comprise Hickson Compact Group 31 is in the midst of complex , ongoing gravitational interactions , evocative of the process of hierarchical structure formation at higher redshifts .
With sensitive , multicolor Hubble Space Telescope imaging , we characterize the large population of < 10 Myr old star clusters that suffuse the system .
From the colors and luminosities of the young star clusters , we find that the galaxies in HCG 31 follow the same universal scaling relations as actively star-forming galaxies in the local Universe despite the unusual compact group environment .
Furthermore , the specific frequency of the globular cluster system is consistent with the low end of galaxies of comparable masses locally .
This , combined with the large mass of neutral hydrogen and tight constraints on the amount of intragroup light , indicate that the group is undergoing its first epoch of interaction-induced star formation .
In both the main galaxies and the tidal-dwarf candidate , F , stellar complexes , which are sensitive to the magnitude of disk turbulence , have both sizes and masses more characteristic of z = 1 –2 galaxies .
After subtracting the light from compact sources , we find no evidence for an underlying old stellar population in F – it appears to be a truly new structure .
The low velocity dispersion of the system components , available reservoir of H i , and current star formation rate of \sim 10 M _ { \odot } yr ^ { -1 } , indicate that HCG 31 is likely to both exhaust its cold gas supply and merge within \sim 1 Gyr .
We conclude that the end product will be an isolated , X-ray-faint , low-mass elliptical .