Acknowledgments

This book stands on the shoulders of the people who built the field and those who chose to explain it.

To the authors of the works that taught generations of engineers — George Sutton and Oscar Biblarz on propulsion, Howard Curtis and David Vallado on orbital mechanics, James Wertz and his collaborators on space mission engineering, and Bate, Mueller, and White, whose Fundamentals of Astrodynamics proved that rigor and clarity are not enemies. Where this book is right, it often echoes them; where it is wrong, the fault is entirely ours.

To the engineers and scientists of NASA, ESA, JAXA, ISRO, Roscosmos, and the commercial space companies, whose technical reports, mission documents, and public data make a book like this possible and verifiable. To the science communicators — Scott Manley chief among them — who have shown that the real physics is more thrilling than any simplification.

To the developers of the open tools this book is built with and computes with: Python, NumPy, SciPy, Matplotlib, Astropy, mdBook, and Jupyter Book. And to the makers of Kerbal Space Program, which has taught orbital intuition to more people than every textbook combined, and sent many of them looking for the equations behind the fun.

To the open-education movement, and to everyone who believes that the knowledge of how humanity reaches space should be free to anyone who wants it.

And to you, the reader, for deciding that "it's not rocket science" was not a good enough reason to stop asking how it works. This book is released under CC BY-SA 4.0 so that you can share it, improve it, and pass it on. Corrections and contributions are genuinely welcome — see CONTRIBUTING.md.