Satellite Ecology: The Dearth of Environment Dependence

Understand

Using the Sloan Digital Sky Survey (SDSS) galaxy group catalogue of Yang et al.

• (2007), we study the average colour and average concentration of satellite galaxies as function of (i) their stellar mass, (ii) their group mass, and (iii) their group-centric radius.
• We find that the colours and concentrations of satellite galaxies are (almost) completely determined by their stellar mass.
• In particular, at fixed stellar mass, the average colours and concentrations of satellite galaxies are independent of either halo mass or halo-centric radius.