For astronomers, black holes pose a challenge. Because they swallow up all of the available light, it is virtually impossible to observe them. However, they do give away their position when electromagnetic radiation escapes from their surrounding environment. Efforts are now being made to visualise these more effectively with the help of the new NuSTAR (Nuclear Spectroscopic Telescope Array) X-ray telescope for which Schott has supplied a mirror substrate made of razor-thin specialized glass for optics. NuSTAR consists of two X-ray telescopes that are parallel aligned. Observation takes place through Wolter Telescopes that are mounted onto an arm that can be extended to a focal length of 10 meters. These concentrate radiation onto 2 detectors found on the body of the satellite. From here, the images are transmitted down to earth.
