British scientists are building the biggest telescope to be launched into space - aiming to probe some of the most distant and mysterious corners of the universe. The X-ray Evolving Universe Spectroscopy, or XEUS, telescope is one of the next generation of space-based observatories that will replace the famous Nasa Hubble Space Telescope, which has orbited Earth since 1990. Led by experts at Leicester University, the ambitious new telescope project has been short-listed by the European Space Agency for launch in the next 10 years.