page_title: Lowell Observatory
section_title: Lowell Discovery Telescope
hierarchical_section_title: Lowell Observatory / Lowell Discovery Telescope
caption_attribution_description: English: The Discovery Channel Telescope 中文: 探索頻道望遠鏡
context_page_description: 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 first trustee was Lowell's third cousin Guy Lowell. Percival's nephew Roger Putnam served from 1927 to 1967, followed by Roger's son Michael, Michael's brother William Lowell Putnam III, and current trustee W. Lowell Putnam.
  Multiple astronauts attended the Lowell Observatory in 1963 while the moon was being mapped for the Apollo Program.
  The observatory operates several telescopes at three locations in the Flagstaff area.
context_section_description: Lowell Observatory owns and operates the Lowell Discovery Telescope (LDT, formerly the Discovery Channel Telescope) located near Happy Jack, Arizona. This 4.3-meter reflecting telescope is the fifth-largest telescope in the contiguous United States and one of the most powerful in the world, thanks to a unique housing that can accommodate up to five instruments at the Ritchey-Chrétien focus. The LDT can switch between any of these instruments in about a minute, making it uniquely suited for time-domain programs as well as opportunity targets such as gamma ray bursts and supernovae.
  The 6700-pound primary mirror measures 4.3 m (170 in) in diameter yet only about 10 cm (3.9 in) in thickness. This finely figured, thin meniscus mirror, held in shape by a 156-element active optics system, regularly delivers sub-arcsecond seeing. The mirror was ground and polished into its parabolic shape at the Optical Fabrication and Engineering Facility of the College of Optical Sciences of the University of Arizona in Tucson.
  The LDT is housed in a 73-foot-tall, 62-foot-diameter metal dome located at an elevation of 7,800 feet (2,400 m) and about 40 miles (64 km) southeast of Flagstaff. Groundbreaking for the facility occurred on July 11, 2005.  A little over six years later, the first image from just the primary mirror was recorded, using a small test camera mounted where the secondary mirror would eventually go. The secondary mirror was installed in January 2012. To celebrate first light, Lowell hosted a gala celebration on July 21, 2012, featuring a keynote address by Neil Armstrong. This was his final public appearance before his death several weeks later.
  The telescope is named for the Discovery Channel television network. Discovery founder and CEO John Hendricks has long been a member of Lowell Observatory’s Advisory Board, and Discovery and John and his wife Maureen made gifts of $16 million toward the $53 million cost of the project. These were gifts, not purchases: Discovery has no ownership in the telescope, nor any direction of the research conducted with it. In return for their contributions, they received naming rights and first right of refusal for use of images in educational broadcasts. Research use proceeds as it would at any other professional telescope.
  Boston University, the University of Maryland, the University of Toledo, Northern Arizona University, and Yale University have joined Lowell as partners with access to DCT.
caption: Lowell Discovery Telescope
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