Biggest space telescope yet proposed would succeed Hubble

Nature : As the Hubble Space Telescope celebrates its 25th anniversary, a group of US astronomers are discussing a potential successor. In their study , commissioned by the Association of Universities for Research in Astronomy, the researchers propose building the High-Definition Space Telescope (HDST), a 12-m-class instrument that, like Hubble, operates at UV and optical wavelengths. The HDST would have a mirror five times the width of Hubble and nearly twice that of the James Webb Space Telescope (JWST), scheduled to launch in 2018. The JWST, however, operates only in IR light, so the researchers say a telescope like the HDST will be needed to continue Hubble‘s search for Earth-like planets and life outside our solar system. Because such a giant telescope could cost more than $10 billion, NASA may need to scale down the project or partner with other space agencies to build it.