SIMBAD references

John Goodricke and Edward Pigott, working in York, England, between 1781 and 1786, determined the periods of variation of eclipsing binaries such as Algol and Beta Lyrae and speculated that the eclipses of Algol might be caused by a "dark body," perhaps even a planet. They also determined the periods of variation of the first two known Cepheid variables, the stars whose period-luminosity relation today enables astronomers to determine distances to distant galaxies. Goodricke holds special interest because he was completely deaf and because he died at the age of 21. The lives and work of these two astronomers are described.