I'm curious about how the temperature of the CMBR compares to the light and temperature of galaxies in general. Basically, I'm wondering how 'hot' are galaxies and how do they contribute to the CMBR readings. Does the temperature of galaxies compare on some scale? Do we have to account for the direct temperature of galaxies, and subtract it from the CMBR somehow? I guess my feeling is, is that there are many galaxies, lying on many lines of sight. I can only assume they must have some temperature reading, although quite cool from far away. Also, does the radiation of the CMBR simply pass through the galaxies, or do they effect the readings somehow. Thank you in advance.