ESO engineers inspect an uncoated M1 segment

A team of ESO engineers, technicians and contractors at Paranal Observatory inspects one of the Extremely Large Telescope (ELT)’s primary mirror segments, still in its protective wrapping, to make sure it was not damaged during its long journey across the ocean. The box in which the segment was transported can be seen on the floor in front of the crane. The mirror segments are each carefully inspected before being coated with a highly reflective silver layer and receiving edge sensors to detect misalignments.