Explained: What is thirty meter telescope?

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.

Last week, Hawaii saw protests against plans to start construction of a giant telescope atop Mauna Kea, the US state s highest mountain at 14,000 feet. Already the site of a number of observatories and 13 large telescopes, Mauna Kea is considered sacred by native Hawaiians who believe that such constructions defile the mountain. After a Supreme Court order recently cleared construction of the newest one, called the Thirty Metre Telescope , locals blocked access to the roads last week, leading to several arrests.

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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. For the first time in history we will be capable of detecting extraterrestrial life, Dumas told The AP. The study of black holes is another objective. 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.

If the Thirty Metre Telescope cannot be built on Mauna Kea, Spain s Canary Islands is a backup site.