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Astronomy

Space Interferometry for Stellar Imaging

Quick fact

The first space-based optical interferometry experiment, on the NASA Keck telescopes, achieved an angular resolution of about 0.005 arcseconds—equivalent to reading a newspaper from 10 kilometers away.

Why this is interesting

You know that a telescope's power comes from its size. But what if you could combine two smaller telescopes to act like one giant one? Space interferometry makes the impossible possible, revealing the surfaces of distant stars.