Last ELT M1 segment blanks off for delivery

The last segments for the ELT’s primary mirror (M1) have been successfully cast by German company SCHOTT and are seen in the photo being loaded for transportation. The M1 blanks are made from ZERODUR©, a low-expansion glass-ceramic material developed by SCHOTT and optimised for the extreme temperature ranges of the ELT’s site in the Atacama Desert. The next step in the segments’ journey will take them to French company Safran Reosc, which is responsible for cutting each segment blank to the right shape and polishing it.