Telescope Array Begins Interferometric Imaging of Stars at Optical Wavelengths

The extraordinary images of the binary star Capella published in the February issue of Astronomy and Astrophysics, and reproduced on this page, herald the arrival of an important new astronomical technique: interferometric imaging with separated optical telescopes. The images were produced by John Baldwin and coworkers at the Cambridge Optical Aperture Synthesis Telescope (coast), a Y‐shaped interferometric array of four modest, movable telescopes, with a maximum separation of 100 meters. Coast sits alongside the much larger radio telescopes of Cambridge University's Mullard Radio Astronomy Observatory.