Lowell Observatory Lowell Observatory Lowell Observatory is an astronomical observatory in Flagstaff, Arizona, United States. Lowell Observatory was established in 1894, placing it among the oldest observatories in the United States, and was designated a National Historic Landmark in 1965. In 2011, the Observatory was named one of "The World's 100 Most Important Places" by TIME. It was at the Lowell Observatory that the dwarf planet Pluto was discovered in 1930 by Clyde Tombaugh. The observatory was founded by astronomer Percival Lowell of Boston's Lowell family and is overseen by a sole trustee, a position historically handed down through the family. The
Heidelberg-Königstuhl State Observatory Heidelberg-Königstuhl State Observatory Heidelberg-Königstuhl State Observatory () is a historic astronomical observatory located near the summit of the Königstuhl hill in the city of Heidelberg in Germany. The predecessor of the current observatory was originally opened in 1774 in the nearby city of Mannheim but degradation of observational conditions there resulted in a relocation to the Königstuhl in 1898. The observatory forms part of the Center of Astronomy of the University of Heidelberg. The Max Planck Institute for Astronomy opened on an adjacent site in 1967. Prof. Dr. Andreas Quirrenbach is the observatory's director since 2005. The instrumentation of the