Our GMRT H i observations of the ultra diffuse galaxy ( UDG ) UGC 2162 , projected \sim 300 kpc from the centre of the M 77 group , reveal it to a have an extended H i disk ( R _ { HI / R _ { 25 } } \sim 3.3 ) with a moderate rotational velocity ( V _ { rot } \sim 31 km s ^ { -1 } ) .
This V _ { rot } is in line with that of dwarf galaxies with similar H i mass .
We estimate an M _ { dyn } of \sim 1.14 \times 10 ^ { 9 } M _ { \odot } within the galaxy ’ s R _ { HI } \sim 5.2 kpc .
Additionally , our estimates of M _ { 200 } for the galaxy from NFW models are in the range of 5.0 to 8.8 \times 10 ^ { 10 } M _ { \odot } .
Comparing UGC 2162 to samples of UDGs with H i detections show it to have amongst the smallest R _ { e } with its MH i /M _ { * } being distinctly higher and g – i colour slightly bluer than typical values in those samples .
We also compared H i and dark matter ( DM ) halo properties of UGC 2162 with dwarf galaxies in the LITTLE THINGS sample and find its DM halo mass and profile are within the range expected for a dwarf galaxy .
While we were unable to to determine the origin of the galaxy ’ s present day optical form from our study , its normal H i rotation velocity in relation to its H i mass , H i morphology , environment and dwarf mass DM halo ruled out some of the proposed ultra diffuse galaxy formation scenarios for this galaxy .