heptane. n. 1. (Elements & Compounds) an alkane existing in nine isomeric forms, esp the isomer with a straight chain of carbon atoms (n-heptane), which is found in petroleum and used as an anaesthetic. Formula: C7H16. [C19: from hepta- + -ane, so called because it has seven carbon atoms].
technically it's not any of those three... After the Apollo program in the late 1960's ended, the president of the United States, Richard Nixon declared in 1973 that the USA would build the Space Shuttle to continue space exploration in low earth orbit.
As Discovery prepares for her last space shuttle launch, NASA's human spaceflight program shifts from space station ferry-service to missions to the moon, Mars, and beyond. The space shuttle Discovery prepares for launch at Kennedy Space Center's launch pad 39A, in Cape Canaveral, Fla., Feb. 23.