Clyde William Tombaugh was an American astronomer. He discovered Pluto in 1930, the first object to be discovered in what would later be identified as the Kuiper belt. At the time of discovery, Pluto was considered the ninth planet, but was reclassified as a dwarf planet in 2006. Tombaugh also discovered many asteroids, and called for the serious scientific research of unidentified flying objects.
Following the discovery of the planet Neptune in 1846, there was considerable speculation that another planet might exist beyond its orbit. The search began in the mid-19th century and continued at the start of the 20th with Percival Lowell's quest for Planet X. Lowell proposed the Planet X hypothesis to explain apparent discrepancies in the orbits of the giant planets, particularly Uranus and Neptune, speculating that the gravity of a large unseen ninth planet could have perturbed Uranus enough to account for the irregularities.
Percival Lowell was an American businessman, author, mathematician, and astronomer who fueled speculation that there were canals on Mars, and furthered theories of a ninth planet within the Solar System. He founded the Lowell Observatory in Flagstaff, Arizona, and formed the beginning of the effort that led to the discovery of Pluto 14 years after his death.
Yerkes Observatory is an astronomical observatory located in Williams Bay, Wisconsin, United States. The observatory was operated by the University of Chicago Department of Astronomy and Astrophysics from its founding in 1897 until 2018. Ownership was transferred to the non-profit Yerkes Future Foundation (YFF) in May 2020, which began millions of dollars of restoration and renovation of the historic building and grounds. Yerkes re-opened for public tours and programming in May 2022. The April 2024 issue of National Geographic magazine featured a story about the Observatory and ongoing work to restore it to relevance for astronomy, public science engagement and exploring big ideas through art, science, culture and landscape. The observatory offers tickets to programs and tours on its website.
A refracting telescope is a type of optical telescope that uses a lens as its objective to form an image. The refracting telescope design was originally used in spyglasses and astronomical telescopes but is also used for long-focus camera lenses. Although large refracting telescopes were very popular in the second half of the 19th century, for most research purposes, the refracting telescope has been superseded by the reflecting telescope, which allows larger apertures. A refractor's magnification is calculated by dividing the focal length of the objective lens by that of the eyepiece.
James Walter "Jim" Christy is an American astronomer known for discovering Charon, the largest moon of the dwarf planet Pluto.
William Henry Pickering was an American astronomer. Pickering constructed and established several observatories or astronomical observation stations, notably including Percival Lowell's Flagstaff Observatory. He led solar eclipse expeditions and studied craters on the Moon, and hypothesized that changes in the appearance of the crater Eratosthenes were due to "lunar insects". He spent much of the later part of his life at his private observatory in Jamaica.
Vesto Melvin Slipher was an American astronomer who performed the first measurements of radial velocities for galaxies. He was the first to discover that distant galaxies are redshifted, thus providing the first empirical basis for the expansion of the universe. He was also the first to relate these redshifts to velocity.
Marc William Buie is an American astronomer and prolific discoverer of minor planets who works at the Southwest Research Institute in Boulder, Colorado in the Space Science Department. Formerly he worked at the Lowell Observatory in Flagstaff, Arizona, and was the Sentinel Space Telescope Mission Scientist for the B612 Foundation, which is dedicated to protecting Earth from asteroid impact events.
Carl Otto Lampland was an American astronomer. He was involved with both of the Lowell Observatory solar system projects, observations of the planet Mars and the search for Planet X.
1604 Tombaugh, provisional designation 1931 FH, is a rare-type Eos asteroid from the outer region of the asteroid belt, approximately 32 kilometers in diameter. It was discovered on 24 March 1931, by American astronomer Carl Otto Lampland at Lowell Observatory in Flagstaff, Arizona, in the United States. It was named after the discoverer of Pluto, Clyde Tombaugh.
An astrograph is a telescope designed for the sole purpose of astrophotography. Astrographs are mostly used in wide-field astronomical surveys of the sky and for detection of objects such as asteroids, meteors, and comets.
Anderson Mesa Station is an astronomical observatory established in 1959 as a dark-sky observing site for Lowell Observatory. It is located at Anderson Mesa in Coconino County, Arizona, about 12 miles (19 km) southeast of Lowell's main campus on Mars Hill in Flagstaff, Arizona.
The Lowell Discovery Telescope (LDT), formerly the Discovery Channel Telescope (DCT), is a 4.3 m (170 in) aperture telescope owned and operated by Lowell Observatory. The LDT was built at a dark sky site in the Coconino National Forest near Happy Jack, Arizona. Happy Jack is located at an elevation of 2,360 m (7,740 ft) and is approximately 65 km (40 mi) south-south-east of Flagstaff. The project was initially a partnership between Discovery Communications and Lowell Observatory. The research partnerships have been extended to include Boston University, The University of Maryland, The University of Toledo, Northern Arizona University, and Yale University. The telescope cost $53 million. It significantly augments Lowell Observatory's observational capability and enables pioneering studies in a number of important research areas.
The United States Naval Observatory Flagstaff Station (NOFS), is an astronomical observatory near Flagstaff, Arizona, US. It is the national dark-sky observing facility under the United States Naval Observatory (USNO). NOFS and USNO combine as the Celestial Reference Frame manager for the U.S. Secretary of Defense.
Roger Lowell Putnam was an American politician and businessman. A member of the prominent Lowell family of Boston, he served as Mayor of Springfield, Massachusetts, from 1937 until 1943, and as director of the Economic Stabilization Administration from 1951 until 1952. During his short tenure in federal office, the nation's steelworkers struck—leading United States President Harry S. Truman to seize the nation's steel mills.
Doyle Peak is a peak in the Coconino National Forest, and the fourth-highest peak in the San Francisco Peaks of northern Arizona. It is the sixth-highest named point in the state of Arizona, with an elevation of 11,464 feet (3,494 m).
Robert-Aglaé Cauchoix was a French optician and instrument maker, whose lenses played a part in the race of the great refractor telescopes in the first half of the 19th century.
Wrexie Leonard, also known as Louise Leonard, was an American astronomer who worked as an assistant to Percival Lowell and published her observations of Mars. The Leonard Crater on Venus is named for her.
Elizabeth Langdon Williams was an American human computer and astronomer whose work helped lead to the discovery of Pluto, or Planet X.
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