Shoot the Moon by Isa Arsen

 Annie Fisk loves numbers, thanks to her scientist father. She eventually becomes a physicist, though in the early 1960s there's not much call for women physicists. One of her professors, who realizes how smart she is, tells her to take any job at NASA that she can get, just to get a foot in the door. So she gets a job as a secretary. One day she storms into her boss's office and tells him he's doing all his calculations wrong. His first impulse is to ask her to dinner but recognizing how brilliant she is makes him recommend her for a job in the computer programming department. That whole story line was my favorite part of this book.

The other parts of the store (bouncing between time periods) tell about her lonely childhood as her father is wracked with guilt from working on the atom bomb and her mother is trying to keep her husband on an even keel. And her imaginary friend Diana, who turns out to play a pivotal role later in the book. There are also 2 love affairs--one with a woman named Evie and one with a NASA engineer named Norm. I liked the last third of the book a lot, though I thought the middle kind of dragged a little.