200 metre telescope looks at GRAVITY of black holes

The GRAVITY instrument combines the light from multiple telescopes to form a virtual telescope up to 200 metres across, using a technique called interferometry. This enables the astronomers to detect much finer detail in astronomical objects than is possible with a single telescope.

Credit:
ESO/GRAVITY consortium/NASA/ESA/M. McCaughrean

http://www.eso.org/public/news/eso1601

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