To understand what that co-authorship means, you have to understand what producing a technical handbook like this required.

It was not a matter of compiling existing knowledge — the knowledge being compiled was, in significant part, being developed for the first time.

It required the ability to work through the mathematics of orbital mechanics and interplanetary trajectories from first principles, to verify results, to organize the calculations in ways that would be useful to other engineers, and to present the material with the precision that a technical reference document requires.

It required, in other words, exactly the kind of mathematical sophistication that Mary Ross had been building across four decades of study and professional practice.