As Nasa basked in the success of discovering an earth-like planet around 1,400 light years away , China entered the final sprint on what will be the largest radio telescope in history, designed to search for signs of life on distant worlds. Kepler 452b was detected by the US space agency's Kepler Space Telescope, Nasa said on Thursday. It orbits a star similar to our own, at the right distance to potentially support life. Extra-planetary transmissions from that distance are well beyond the reach of any instruments currently in operation, but not for the Five-hundred-metre Aperture Spherical Telescope (FAST) currently under construction in China. "The universe is full of radioactive noise. Distant signals are like the singing of cicadas in a thunder storm, without an incredibly sensitive 'ear', they can't be identified," professor Nan Rendong, chief scientist on the FAST project, told Xinhua. Nicknamed the Sky Eye, FAST is designed to capture extremely faint radio transmissions from over 1,000 light years away. If things go to plan, it will begin operation next year. Under construction since June 2011, FAST is being built over an enormous, naturally-formed pit in the scenic Karst landscape of China's Guizhou province. On Thursday, hours before Nasa's milestone announcement, hundreds of scientists and engineers at the site began maybe the most challenging part of the 700 million yuan (US$112 million) project – installing the mirrors. The reflective disk used in FAST will dwarf that of the current largest telescope, the US-built 300 metre Arecibo Observatory in Puerto Rice. Comprising nearly 460,000 reflective mirrors with a total surface area exceeding 250,000 square metres, the FAST disk is larger than 30 soccer fields. The mirrors must be placed together precisely, with the room for error less than the thickness of a hair. A minute gap between the mirrors could cause significant signal disruption and render the entire project useless. All the signals collected from the cosmos by the mirrors will be reflected to a sensor around the size of a sleeping pill. FAST will give China a major boost in the race to search for alien life, Chinese astronomers said. “FAST can detect incredibly distant places … even extraterrestrial civilisations,” Wu Xiangping, secretary general of the Chinese Astronomy Society, told Xinhua. Tianjin-based astronomer Shi Zhicheng agreed. “If intelligent aliens exist, the messages that they produced or left behind, if they are being transmitted through space, can be detected and received by FAST,” he said. But many challenges await the Chinese researchers before they can fire up the gigantic facility next year. For example, to focus on a specific object in space, the mirrors must be adjusted individually for the best angle, but the technology and equipment to precisely control this 10,000-ton machine has never been used or tested before, according to a Chinese space scientist who declined to be named. It could take the researchers working on the project many years to improve the hardware and software before FAST can make any reliable findings, the scientist said.