The next pieces of the jigsaw for the European Extremely Large Telescope (E-ELT) — the world’s biggest eye on the sky — are coming together. At ESO’s Garching facility in Germany, a full-size mock-up of a small section of the E-ELT primary mirror and its support structures provides a first test of multiple segments of the E-ELT’s main mirror. Four of the 1.45-metre segments — the final mirror will have 798 — are being put through their paces to see how these hexagonal mirrors and their complex support units behave in real conditions, and whether they match the exacting requirements needed for the telescope.
The mirror segments are made from different types of material from different manufacturers and are not yet coated to make them reflective. The current tests focus on the mechanical support systems, whose advanced sensors and actuators are used to keep the separate segments in the right position and shape, so that together they can form a perfect, giant mirror. … (ESO)