Celestial projector
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Fortuna gave Galileo Galilei a celestial projector which, despite his blindness, was able to show him the stars. He was able to use it to spy on Fortuna and Cleaver, but chose not to confront her as he wanted to continue pretending that she was his daughter.
The Eighth Doctor let Galileo keep the projector, although he asked him to make sure that he kept it hidden. (AUDIO: The Galileo Trap)