Feature Eyes on the sky A roster of new and proposed telescopes By Science News May 15, 2009 at 4:55 pm - More than 2 years ago Share this:Share Share via email (Opens in new window) Email Click to share on Facebook (Opens in new window) Facebook Click to share on Reddit (Opens in new window) Reddit Click to share on X (Opens in new window) X Click to print (Opens in new window) Print E-ELT Full name: The European Extremely Large Telescope Mirror: 42 meters diameter Timeline: Projected to open in 2018 Projected cost: €1 billion Basic mission: largest ground-based optical/near-infrared telescope Location: Possible sites in Chile, Argentina, Canary Islands, Morocco Online: E-ELT Homepage – ESA GMT Full name: Giant Magellan Telescope Mirror: 24.5