The telescope is being built by an international collaboration of government organisations and educational institutions, at a cost of $1.4 billion. “Thirty Metre” refers to the the 30-metre diameter of the mirror, with 492 segments of glass pieced together, which makes it three times as wide as the world’s largest existing visible-light telescope. The larger the mirror, the more light a telescope can collect, which means, in turn, that it can “see” farther, fainter objects.
The Associated Press quoted Christophe Dumas, head of operations for the Thirty Metre Telescope, as saying that it would be more than 200 times more sensitive than current telescopes, and would be able to resolve objects 12 times better than the Hubble Space Telescope.
One of its key uses will be the study of exoplanets, many of which have been detected in the last few years, and whether their atmospheres contain water vapour or methane — the signatures of possible life. While these have been observed in detail within the Milky Way, the next galaxy is 100 times farther away; the Thirty Metre Telescope will help bring them closer.
Thirty Metre Telescope is built on Mauna Kea mountain, Hawaii, USA. Spain’s Canary Islands is a backup site, in case the telescope is not established in Hawaii due to protests by local people.