1672 - Geminiano Montanari notices that Algol's brightness varies
1686 - Gottfried Kirch notices that Chi Cygni's brightness varies
1718 - Edmund Halley discovers stellar proper motions by comparing his astrometric measurements with those of the Greeks
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
1961 - Chushiro Hayashi publishes his work on the Hayashi track of fully convective stars
1963 - Fred Hoyle and William Fowler conceive the idea of supermassive stars
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
1967 - Gerry Neugebauer and Eric Becklin discover the Becklin-Neugebauer object at 10 microns