High Quality Content by WIKIPEDIA articles! STS-131 (ISS assembly flight 19A) was a NASA Space Shuttle mission to the International Space Station (ISS). Space Shuttle Discovery launched on 5 April 2010 at 6:21 am from Kennedy Space Center`s launch pad 39A, and landed at 9:08 am on 20 April 2010 on runway 33 at the Kennedy Space Center`s Shuttle Landing Facility. The mission marked the longest flight for space shuttle Discovery.