Introduction

2015-07-11

That’s one small step for a man, one giant leap for mankind. – Neil Armstrong, first human being on the Moon

Are you curious about the “How?” behind space exploration and satellite operating? This document might help you quench that thirst for knowledge. Although it is still very much in the making, it tries to clearly explain the technical terms and to guide you through the mathematics.

If some part of it seems to be unclear or lacking explanation, do not hesitate to contact the author at author@airsick.guide.

Kerbal Space Program

Kerbal Space Program [1] is a rocket simulation game; it lets you build, launch and pilot a rocket to put up satellites, send probes, land rovers, and have Kerbals do SCIENCE.

A big advantage a KSP player has over actual rocket crafters is that she can have rockets exploding without having to worry about consequences. Half the fun of the game comes from finding out why your next rocket will fail; thus, I urge you roll rockets to the launchpad early and not bother thinking of every little thing that could go wrong.

Airsick will not cover the initiation to the game, since the interface is specific to the game and prone to change. The game offers an intuitive way to assemble rockets and has a handy interface to control the flight. Rather, it will expose, explain and detail real principles of physics that the game mimics. This information can be read simply for curiosity, or can serve to design more precise launches in the game. When possible, example values will be taken from reality or KSP.

KSP is a proprietary software. You can play the demo for free, but will be limited to an older version with only a few parts available for building. The demo is way harder and the complete game way richer.
This document is intended to provide information both for beginners and actual physicists. The first few chapters are an introduction to the elementary concepts used within this book. In every chapters accurate derivations and complete proofs are developed wherever needed. If you are not interested in the specifics of a demonstration or have already some knowledge of basics physics, feel free to skip irrelevant parts.

This document was written using Markdown and LaTeX. Markdown is a very simple format for rich text; LaTeX is currently the most flexible way to write formulas and draw complex graphs (using TiKZ).

The source is made so as to be compiled into either a PDF or a set of webpages.

• PDF: the Markdown/LaTeX source is converted to pure LaTeX using Pandoc; the LaTeX files are then compiled with pdflatex
• HTML: the Markdown is converted to HTML using Pandoc, inline LaTeX (formulas)
• are converted to MathML using ttm, and TikZ pictures are converted to SVG files using latex and dvisgm

A few more details:

• since several browsers still do not support MathML, including Google Chrome, Opera and Microsoft Internet Explorer, the Javascript library MathJax is conditionnaly enabled to fill the gap
• some discrepancies between PDF and HTML generations are handled by Pandoc filters.
• to be more precise, during the PDF generation, TikZ pictures are converted to individual PDFs using (latex and dvipdf)

Credits

This document makes extensive use of pictures, diagrams and various illustrations. When an external image was included as a figure, a reference to the source is linked in the caption (e.g. [2]).

Sources for the other illustrations:

• front cover [3]
• chapter banners [4]
• back cover [1]

1. “Kerbal Space Program”,
2011–2016, space simulation game, Squad,
https://www.kerbalspaceprogram.com/

2. “Orbital Mechanics”,
2014, webcomic, xkcd,
https://xkcd.com/1356/

3. “Three Kerbal Mun”
2011, deviantART publication, MK01,
https://mk01.deviantart.com/art/Three-Kerbal-Mun-272960572

4. “Renderings of my favourite planets/muns in banner form”,
2013, KSP forum post, Lunniy Korabl,