Working on the mechanism of the ELT's main mirror

In the large intergration hall at ESO's Headquarters in Garching, Germany, Paulo Ferreira is working on the mechanism for ESO's Extremely Large Telescope (ELT) M1 mirror cell. Too large to be made from a single piece of glass, the 39-metre-diameter mirror will consist of 798 segments, measuring close to 1.5 metres across and weighing 250 kg, including its support. Since the segments have to work together as a single mirror, they require specific infrastructure and control schemes.