The Arecibo Observatory in Puerto Rico will soon lose its title of the largest single aperture radio telescope ever constructed. The Chinese are building a Five hundred meter Aperture Spherical Telescope, shortened to FAST, which when complete in 2016 will be the world's largest radio telescope and three times more sensitive than the Arecibo Observatory. The telescope is being built in a remote part of Guizhou province in southern China, in an area that is “radio silent” as there are no towns and cities within a radius of 5 km and only one county centre within 25 km.

FAST's gigantic dish will be placed in a natural crater-like depression and will consist of 4,600 triangular panels that could be moved to change the overall shape of the dish’s reflective surface, allowing it to scan large swathes of the sky. Astronomers expect FAST to uncover thousands of new galaxies and deep-sky objects up to 7 billion light years away. FAST will probably remain the best in the world in the next twenty to thirty years after it is completed.

Artist’s rendering of what FAST would look like when complete. Photo credit