How Many Space Shuttles Are There

Nasa added the prefix of sts space transportation system to each shuttle mission.
How many space shuttles are there. Two of the shuttles columbia and challenger were lost in accidents and the rest have been retired to museums. Challenger enterprise columbia discovery atlantis endeavour. Total number of nasa space shuttle missions that will have flown between 1981 and 2011. Its official program name was space transportation system sts taken from a 1969 plan for a system of reusable spacecraft of which it was the only item funded for development.
The space shuttle was a partially reusable low earth orbital spacecraft system operated by the national aeronautics and space administration nasa. 6 space shuttles were built although only 5 of them spaceworthy. Nasa has operated six space shuttles beginning with the prototype orbiter which was flown in earth s atmosphere during landing and flight tests. Five complete space shuttle orbiter vehicles were built and flown on a total of 135 missions from 1981 to 2011 launched from the kennedy space center ksc in florida.
Destroyed during reentry killing all seven astronauts on board. Disintegrated after launch killing all seven astronauts on board. 4 of them are still around in various museums.