Northern Arizona University (NAU) is a publicresearch university in Flagstaff, Arizona, United States. Founded in 1899, it was the third and final university established in the Arizona Territory. The university is divided into seven academic colleges offering about 130 undergraduate andgraduate programs, and various academic certificates. Students can take classes and conduct research in Flagstaff, online, and at more than 20 statewide locations, including the Phoenix Biomedical Core research campus. As of fall 2023, 28,194 students were enrolled with 21,550 at the Flagstaff campus.Northern Arizona University is one of the three universities governed by the Arizona Board of Regents and is accredited by the Higher Learning Commission. It is classified among "R1: Doctoral Universities – Very high research activity". NAU is ranked No. 192 in the National Science Foundation (NSF) national research rankings for fiscal year 2023. NAU's astronomy faculty led the observations of the NASA DART planetary defense mission, co-discovered several astronomical bodies such as Eris and Sedna, and are major participants in the search for the hypothetical Planet Nine. The university is a primary institution of the local Lowell Observatory. Alumni include 4 Truman Scholars, 11 Goldwater Scholars, and 3 Udall Scholars.The NAU Lumberjacks compete in the NCAA Division I primarily as part of the Big Sky Conference, and have won six national championships in cross country running. At an elevation of 6,950 ft (2,120 m) above sea level, the school's athletic facilities are used by Olympic and professional athletes worldwide for prestige high altitude training.