The biggest that have ever been built are those in the two ten-metre (394 inch) Keck telescopes on Mauna Kea, but each of those had to be assembled from 36 separate pieces.

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The work, which is described in the journal Nature, actually draws on observations made by several astronomical facilities, including the Keck and James Clerk Maxwell telescopes in Hawaii and the Hubble Space Telescope in orbit around the Earth.

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The Keck interferometer, now under construction at Mauna Kea on Hawaii, will combine four 1.8-metre telescopes to mimic a 100-metre telescope in just this way.

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