What is "astrodome"

n. A transparent dome in the fuselage of an aircraft or spacecraft through which navigational observations may be made

n. a transparent dome on top of an airplane where the navigator can make celestial observations

The NRG Astrodome, also known as the Houston Astrodome, is the world's first multi-purpose, domed sports stadium, located in Houston, Texas. Construction on the stadium began in 1962, and it officially opened in 1965. It served as the second home to the Houston Astros of Major League Baseball (MLB) from its opening in 1965 until 1999, and the home to the Houston Oilers of the National Football League (NFL) from 1968 until 1996, and also the part-time home of the Houston Rockets of the National Basketball Association (NBA) from 1971 until 1975. Additionally, the Astrodome was the primary venue of the Houston Livestock Show and Rodeo from 1966 until 2002. When opened, it was named the Harris County Domed Stadium and was nicknamed the " Eighth Wonder of the World".

While originally utilizing a natural grass playing surface, the Astrodome became the first major sports venue to feature artificial turf, which became known as AstroTurf. In another technological first, the Astrodome featured the "Astrolite", which was the first animated scoreboard. The Astrodome received considerable renovations in 1988 that significantly expanded seating, and altered many original features.

The Astrodome's primary tenants have since moved to other, newly constructed venues; the Astros moved to Minute Maid Park, while Houston Texans—the successor to the Houston Oilers—began play nextdoor at the NRG Stadium. In 2005, the Astrodome was used as a shelter for residents of New Orleans affected by Hurricane Katrina. The venue regularly hosted events until it was declared non-compliant with fire code by the Houston Fire Department in 2008. Parts of it were demolished in 2013, after several years of disuse. In 2014 it was listed on the National Register of Historic Places.

An astrodome is a hemispherical transparent dome fitted in the cabin roof of an aircraft to allow the use of a sextant during astro-navigation.

Prior to the introduction of electronic means of navigation the only way to fix an aircraft's position at night was by taking star sights using a sextant in the same manner as that used by marine navigators for hundreds of years on board ships. To do this requires a 360- degree view of the horizon and the astrodome was devised to allow an uninterrupted view of the sky from horizon to horizon.

Astrodomes were prominent on many Royal Air Force (RAF) and Commonwealth operated multi-engined aircraft of the Second World War, and on foreign aircraft ordered by them for their use, such as the Liberator and Dakota, as a considerable part of the RAF's operations and other flying were carried out at night.

Similar hemispherical-shape domes were also used for sighting remotely-operated gun turrets on World War II heavy bombers - both the Heinkel He 177A, with a single forward dorsal dome to aim its remotely-operated FDL 131 twin MG 131 dorsal turret, and the complex sighting system for the American B-29 Superfortress heavy bomber's quartet of remote gun turrets used such "astrodome" enclosures for defensive turret-aiming/firing purposes.