2 things science and human progress accomplished on this date.
1781
A new planet doubles the solar system
From the garden of his house in Bath, England, William Herschel spotted a faint object through his homemade telescope that turned out to be Uranus, the first planet found since ancient times. In a single night he roughly doubled the known reach of the solar system.
Lowell Observatory announced that Clyde Tombaugh, a young self-taught astronomer, had found a distant new world beyond Neptune by comparing photographic plates night after night. Named Pluto, it was the most far-flung object then known in the Sun's family.