Test setup for the European 1.2m EUCLID space telescope
In line with the delivery of the EUCLID mirrors and the collimator to be used for testing the satellite, AMOS also provided a thermal tent, supporting hardware and special cranes that will allow to handle and cool down the 600 MEUR EUCLID telescope inside the 5m-diameter vacuum chamber in the Centre Spatial de Liège (CSL).
The EUCLID telescope will be tested by CSL under the vacuum and conditions of space. The complexity of the test is that the telescope has to be cooled down to -173°C and tested under those conditions. To achieve such low temperature, the telescope is enveloped by a thermal tent – a set of metal panels in which liquid nitrogen and liquid helium are circulating. Some of those panels will be cooled down to -253°C to reach the proper telescope temperatures.
The process to place the thermal tent around the telescope is complex. A special crane is used to affix the telescope vertically on a dedicated carriage. The thermal tent is then slid around the telescope. The carriage then moves the telescope and tent to a horizontal position and the whole is fixed on the optical bench, which is then slid into the chamber. All those delicate operations have to be executed with very sensitive hardware weighting more than two tons.
While this Mechanical Ground Support Equipment (MGSE) has no optic inside, it shall allow positioning the tent with a high accuracy and a high reliability: the space allowed between the telescope and the tent panels is very limited. The tent needs to slide with precision around the telescope. Reliability is key. Any contact between the telescope and the tent may create damage to the telescope and set back the mission by several months. In the same way, such unwanted contact could also damage the tent or create frigorific liquid leaks and hamper the proper start of the tests.
EUCLID is a space telescope designed to study the Dark Universe. It will map the 3D distribution of two billion galaxies distributed over most of the sky and the dark matter associated with them. EUCLID should be launched summer 2023 from the Guiana Space Center in Kourou.