It's set in the 1950's, VERY early post apocalyptic (meteor falls, climate is starting to change, but after the initial cleanup many people deny that anything is going to happen) The MC is a woman who flew fighter pilots in WW2 and is a brilliant mathmetician, and what they called a Computer when computers were human. It's at the ground floor of alternate history "if we needed desperately to get into space" at that time
