Animation of the European Extremely Large Telescope E_ELT. This telescope is planned to be built by the European Southern Observatory ESO on the Cerro Armazones mountain in Chile. The E_ELT will have a primary mirror with a diameter of 39.3 metres, made up of 798 hexagonal segments. This will make it the largest of the planned next generation of ground_based telescopes. It will operate in the visible light and near_infrared range of the spectrum, and will mostly be used to search for and study extrasolar planets, specifically Earth_like ones, and the regions around stars in which they form. It will also study black holes and early galaxies, and attempt to measure the expansion of the universe. The E_ELT recieved the green light in June 2012, and will take around ten years to build, at a cost of just over one billion Euros.