Surface photometry of the M31 satellites M32 and NGC 205 is compared to numerical simulations of satellite destruction to constrain orbital parameters and the interaction history of the M31 subgroup. Our analysis reveals the following preliminary results: (1) Generic features of tidal disruption in the simulations include an extended ``extra-tidal’’ excess region and an inner depletion zone, both of which are observed in M32 and NGC 205; (2) M32 is likely to be on a highly eccentric orbit well away from pericenter; (3) Surface brightness and luminosity evolution estimates for M32, the prototypical compact elliptical galaxy, imply that it is not simply the residual core of a tidally-stripped normal elliptical galaxy, but was instead formed in a truncated state.

生成讲解博客的中文版本

生成AI智能校验的中文版本