English Encyclopedia
Arizona-AZ
Grand Canyon National Park, located in northwestern Arizona, is the 15th site in the United States to have been named a national park.
The National Radio Astronomy Observatory (NRAO) is a federally funded research and development center of the United States National Science Foundation operated under cooperative agreement by Associated Universities, Inc for the purpose of radio astronomy. NRAO designs, builds, and operates its own high-sensitivity radio telescopes for use by scientists around the world.
