🛰️ Thermal Vacuum Test: Pump-Down, Mean Free Path and Radiative Balance (2D section)

Section of a thermal vacuum chamber holding a satellite test article inside a cooled shroud. Set the shroud temperature, surface emissivity, internal heat, pumping speed and outgassing, and watch the pressure fall, the gas conduction vanish and the payload settle at its radiative balance temperature. Same Stefan-Boltzmann and mean-free-path relations as the 3D page, with four in-page numerical checks.