Tsiolkovsky is considered one of the founding fathers of rocketry and astronautics. Long before the Wright brothers' first plane flew 120 feet, he was thinking space travel. And when it was still science fiction to most people, he was developing the theory, and doing the math, for multistage rockets.
On this day in 1764 - September 17th - English astronomer John Goodricke was born.
Goodricke is best known for his study of the variable star Algol. He was the first to propose that the variability was due to Algol being two stars orbiting each other. His work earned him an award from the Royal Society. Goodricke College at the University of York is named for him.