### Structural Analysis of Ultra-Faint Dwarf Galaxy Horologium I

We use Hubble Space Telescope (HST) photometry to study the morphology of the low luminosity Milky Way (MW) satellite Horologium I (Hor I). Previous literature values of Hor I are further refined through the fitting of galactic models using a Maximum Likelihood algorithm applied to HST data to fit two density profiles: exponential and Plummer. This ultra-faint dwarf (UFD) galaxy has structural parameters of elliptical half-light radius $a_{h, exp}= 1.99'^{+0.24}_{-0.20}$ for the exponential model and...