Press Release

Last segment of the world’s largest telescope mirror successfully cast

The European Southern Observatory’s Extremely Large Telescope (ESO’s ELT), under construction in the Chilean Atacama Desert, is one step closer to completion. German company SCHOTT has successfully cast the blank for the last of the 949 segments commissioned for the telescope’s primary mirror (M1). With a diameter of more than 39 metres, M1 will be by far the largest mirror ever made for a telescope.