VenSpec-H. A cold-box-in-warm-box proof of concept

VenSpec-H is an infrared spectrometer, part of the EnVision mission of ESA to planet Venus. The core optical part of the instrument needs to be cooled down to -45 °C with a maximum gradient of 2°C, while other parts must stay relatively warm (around 0 °C). This led to a design based on a so-called cold-box-in-warm-box concept with the cold box suspended on top of blade flexures inside the warm box. The proof of this concept is shown here, reporting on the vibration and thermal-vacuum tests that have been performed on a representative breadboard model and the good correlation between the physical and the numerical models.