A consortium of 11 European countries have approved 57 million euros (74.1 million dollars) to fund the design of what will be the world's greatest optical telescope. The so-called Europe Extremely Large Telescope (E-ELT) is budgeted at between 800 million and a billion euros (1.04-1.3 billion dollars).
A design approved by more than 250 ESO astronomers at a four-day meeting in Marseille, southern France, at the start of the month calls for an optical/infrared telescope with a 42-metre (136.5-feet) -diameter composite mirror, the largest in the world. The mirror will comprise 906 hexagonal segments, each 1.45 metres (4.7 feet) in size. Their light will be channelled to an "adaptive optics" system, chiefly comprising a smaller mirror whose shape can be distorted by tiny actuators and helps to correct for image fuzziness that occurs when light passes through Earth's atmosphere.
If all goes well, the E-ELT will start operations in 2018, and will be more than 100 times more sensitive than the present-day largest optical telescopes, led by the 10-metre (32.5-feet) Keck telescope in Hawaii.
It could hugely advance knowledge of planets around other stars, the earliest moments of the Universe, "super-massive" black holes and enigmatic phenomena called dark energy and dark matter.
The initial design sketched for the telescope was an OWL ("OverWhelmingly Large") design with a 100-metre (325-feet) mirror. But this was scaled back in 2005 because it was too costly and too complex to build on ESO's budget timescale.My wish list now to include Inferometry Array of Space based OWLS.
