Clyde Tombaugh Reference Libraries
Planet Pluto -- Pluto is the ninth and smallest planet of our solar system. It was discovered by the astronomer Clyde Tombaugh at the Lowell Observatory in Arizona on February 18, 1930 (although the body was first photographed on March 19, 1915). Tombaugh was searching for a "Planet X" to explain the orbit of Neptune; further analysis, with seven decades more data about Neptune's position,...
- Boughs or branches.
- Warbling of birds in trees.