1) I am trying to run a satellite (CubeSat) simulation using a quarter cut of the model. I am unsure how to apply surface-to-surface radiation across my symmetry planes. Can anyone guide me on this? This satellite has significant internal heat generation so more than solar irradiance is taken into account.

2) My second issue is that radiation to ambient requires an ambient temperature. Since space is a vacuum, I just want to be sure I am on the right track for simulating this.

Thank you

Picture of geometry attached.