Nasa creates world's most powerful telescope

The world's two largest telescopes have been linked to create an optical instrument powerful enough to pinpoint planets orbiting other suns.

Astronomers have gathered starlight from the linked 33ft telescopes at the WM Keck Observatory on top of the dormant Mauna Kea volcano in Hawaii, Nasa officials said.

Using a process called interferometry, the twin telescopes first captured light from HD61294, a faint star in the constellation Lynx. The starlight was then shuttled across a 275ft gap between the telescopes and combined in a way to mimic the light-gathering action of a single, larger telescope.

Anne Kinney, director of Nasa's astronomical search for origins programme, which includes the Keck Interferometer, called it "a fabulous technical advancement for science".

"This will open the possibility of obtaining images with much greater clarity than ever before," she said, equating the device to a single 279ft telescope.

The Keck Interferometer will be tested through the summer, with limited science operations to begin this autumn.