Pluto: A Space Discovery Guide

Pluto: A Space Discovery Guide — page 5
CHAPTER 1 DISCOVERING PLUTO Percival Lowell observes Venus through a telescope at the Lowell Observatory Shortly after the planet Neptune was discovered in 1846 astronomers began debating whether there might be a ninth planet farther out in the solar system There seemed to be something other than Neptune affecting the orbit of Uranus One of the big believers in a ninth planet was a rich Bostonian named Percival Lowell He was an avid astronomer who built an observatory in Flagstaff Arizona in 1894 He began searching for the ninth planet from his observatory in 1906 8