The European Space Agency (ESA) has announced a successful solution to the problem of ice formation on the mirrors of the Euclid telescope, launched in July 2023. After discovering layers of ice on the telescope’s optics in preparation for the mission’s first survey, the project team researched and tested a new ice removal procedure.
Recently it was discovered that the de-icing method worked and Euclid’s vision was restored. This success validates the mission team’s plan to ensure the functionality of the Euclid optical system for the remainder of the mission.
The problem was discovered after science operations specialists noticed a gradual decrease in the light measured by the telescope’s VIS instrument. It turned out that ice formed on the mirrors of the instrument due to condensation of water vapor. After months of research and testing, the team identified the source of the problem and began working on a solution.
The obvious solution was to heat the Euclid, but this could cause deformation of the mechanical structure, requiring special care. So the team started by heating individual mirrors, which restored the telescope’s vision. However, this was a temporary solution and a long-term strategy for regular deicing is currently being sought. ESA promises to continue monitoring the telescope and share new results with the public.