1782 - John Goodricke[?] notices that the brightness variations of Algol are periodic and proposes that it is partially eclipsed by a body moving around it
1964 - Subrahmanyan Chandrasekhar and Richard Feynman develop a general relativistic theory of stellar pulsations and show that supermassive stars are subject to a general relativistic instability
... the channel through their ordinary channels BBC1 and BBC2, using terrestrial signals, and this is seen by some as influential (to a certain limited extent) ...