One of Arizona's most pivotal scientific research facilities is celebrating 125 years of viewing the night sky with a three-day event this week.
Lowell Observatory, situated atop Mars Hill in Flagstaff, dates to 1894, when Percival Lowell founded the facility, the first scientific establishment in Arizona.
Initially intended to help Lowell search for intelligent life on Mars, the observatory is best known for another astronomer's discovery. In 1930, Clyde Tombaugh discovered Pluto, long considered the ninth planet of the solar system (and today classified as a "dwarf planet").
Other achievements at Lowell Observatory include the detection of the expanding universe, co-discovery of the rings of Uranus, co-discovery of Pluto's atmosphere, and a study on the proper motion of stars.
The site's 125th Anniversary Celebration, which runs from June 6 to 8, features numerous public activities, including walking tours, lectures and a preview of the observatory's new Junior Astronomer Program. For more information, visit www.lowell.edu/125years.