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Celestial mechanics cheat sheet
% vim:nolist lbr tw=78 expandtab autoindent nocindent
\documentclass[a4paper]{article}
\usepackage[utf8]{inputenc}
\usepackage[landscape,top=1cm,bottom=1cm,left=1cm,right=1cm]{geometry}
%\usepackage{amsmath}
\pagestyle{empty}
\setcounter{secnumdepth}{0}
\title{Celestial mechanics cheatsheet}
\author{Riku Salminen}
\date{\today}
\begin{document}
\begin{center}
\begin{tabular}{ l | c | c | c | c | c | c}
&
&
Conic section ($f$) &
Ellipse ($E$) &
Hyperbola ($F$) &
Parabola ($D$) &
Universal ($s$) \\
\hline
&
&
$ \frac{p}{e} = x + \frac{r}{e} $ &
$ \frac{\left( x + c \right) ^2}{a^2} + \frac{y^2}{b^2} = 1 $ &
$ \frac{\left( x - c \right) ^2}{a^2} - \frac{y^2}{b^2} = 1 $ &
$ 2p \left( x - q \right) = - y^2 $ &
$ $ \\
eccentricity &
$ e $ &
$ e = \sqrt{1 + \frac{2 \epsilon h^2}{\mu ^2}} $ &
$ 0 < e < 1 $ &
$ e > 1 $ &
$ e = 1 $ &
$ $ \\
semi-major axis &
$ a $ &
$ \frac{p}{1 - e^2} $ &
$ a > 0 $ &
$ a < 0 $ &
$ \infty $ &
$ \alpha = \frac{\mu}{a} = \frac{2 \mu}{r} - v^2 $ \\
semi-minor axis &
$ b $ &
$ $ &
$ \frac{p}{\sqrt{1 - e^2}} = a \sqrt{1 - e^2} $ &
$ \frac{p}{\sqrt{e^2 - 1}} = -a \sqrt{e^2 - 1} $ &
$ \infty $ &
$ $ \\
focal distance &
$ c $ &
$ $ &
$ c = \sqrt{a^2 - b^2} = a e $ &
$ c = \sqrt{a^2 + b^2} = -a e $ &
$ \infty $ &
$ $ \\
%pericenter distance &
%$ q $ &
%$ \frac{p}{1 + e} $ &
%$ $ &
%$ $ &
%$ \frac{p}{2} $ &
%$ $ \\
\hline
% angular momentum &
angul. momentum & % XXX: doesn't fit in one page otherwise :(
$ h $ &
$ \vec{h} = \vec{r} \times \vec{v} = \sqrt{\mu p} = r^2 \dot{f} $ &
$ \sqrt{\mu a \left( 1 - e^2 \right)} $ &
$ \sqrt{-\mu a \left( e^2 - 1 \right)} $ &
$ \sqrt{\mu p} $ &
$ $ \\
orbital energy &
$ \epsilon $ &
$ \epsilon = - \frac{\mu}{2 a} = \frac{v^2}{2} - \frac{\mu}{r} $ &
$ \epsilon < 0$ &
$ \epsilon > 0$ &
$ \epsilon = 0$ &
$ \epsilon = - \frac{\alpha}{2} $ \\
\hline
true anomaly &
$ f $ &
$ $ &
$
\left\{
\begin{array}{ll}
\sin f &= \frac{\sqrt{1 - e^2} \sin E}{1 - e \cos E} \\
\cos f &= \frac{\cos E - e}{1 - e \cos E} \\
\tan \frac{f}{2} &=
\sqrt{\frac{1+e}{1-e}} \tan \frac{E}{2} \\
\end{array}
\right.
$ &
$
\left\{
\begin{array}{ll}
\sin f &= \frac{\sqrt{e^2 - 1} \sinh F}{e \cosh F - 1} \\
\cos f &= \frac{e - \cosh F}{e \cosh F - 1} \\
\tan \frac{f}{2} &=
\sqrt{\frac{e+1}{e-1}} \tanh \frac{F}{2} \\
\end{array}
\right.
$ &
$
\left\{
\begin{array}{ll}
\sin f &= \frac{2 D}{1 + D^2} \\
\cos f &= \frac{1 - D^2}{1 + D^2} \\
\tan \frac{f}{2} &= D \\
\end{array}
\right.
$ &
$ $ \\
eccentric anomaly &
$ E $ &
$ $ &
$
\left\{
\begin{array}{ll}
\sin E &= \frac{\sqrt{1 - e^2} \sin f}{1 + e \cos f} \\
\cos E &= \frac{e + \cos f}{1 + e \cos f} \\
\end{array}
\right.
$ &
$
\left\{
\begin{array}{ll}
\sinh F &= \frac{\sqrt{e^2 - 1} \sin f}{1 + e \cos f} \\
\cosh F &= \frac{e + \cos f}{1 + e \cos f} \\
\end{array}
\right.
$ &
$ D = \tan \frac{1}{2} f $ &
$ dt = r ds $ \\
&
$ $ &
$ $ &
$
\left\{
\begin{array}{ll}
e \sin E &= \frac{\vec{r} \cdot \vec{v}}{\sqrt{\mu a}} \\
e \cos E &= 1 - \frac{r}{a} \\
\end{array}
\right.
$ &
$
\left\{
\begin{array}{ll}
e \sinh F &= \frac{\vec{r} \cdot \vec{v}}{\sqrt{- \mu a}} \\
e \cosh F &= 1 - \frac{r}{a} \\
\end{array}
\right.
$ &
$
\left\{
\begin{array}{ll}
D &= \frac{\vec{r} \cdot \vec{v}}{\sqrt{\mu p}} \\
D^2 &= \frac{r}{q} - 1 \\
\end{array}
\right.
$ &
$ $ \\
partial derivatives &
$ \frac{d}{dt} $ &
$ \dot{f} = \sqrt{\frac{\mu}{p^3}} \left( 1 + e \cos f \right) ^2 $ &
$ \dot{E} = \frac{1}{r} \sqrt{\frac{\mu}{a}} $ &
$ \dot{F} = \frac{1}{r} \sqrt{\frac{\mu}{- a}} $ &
$ \dot{D} = \frac{1}{r} \sqrt{\frac{\mu}{p}} $ &
$ \dot{s} = \frac{ds}{dt} = \frac{1}{r} $ \\
&
$ \frac{d}{dM} $ &
$ \frac{df}{dM} = \frac{df}{dE} \frac{dE}{dM} $ &
$ \frac{dE}{dM} = \frac{1}{1 - e \cos E} $ &
$ \frac{dF}{dM} = \frac{1}{e \cosh F - 1} $ &
$ \frac{dD}{dM} = \frac{2}{D^2 + 1} $ &
$ \frac{d}{dt} = \frac{ds}{dt} \frac{d}{ds} = \frac{1}{r} \frac{d}{ds} $ \\
&
$ \frac{df}{dE} $ &
$ $ &
$ \frac{df}{dE} = \frac{\sqrt{1-e^2}}{1 - e \cos E} $ &
$ \frac{df}{dF} = \frac{\sqrt{e^2 - 1}}{e \cosh F - 1} $ &
$ \frac{df}{dD} = \frac{2}{D^2 + 1} $ &
$ \frac{d}{ds} = r \frac{d}{dt} $ \\
universal variable &
$ s $ &
$ $ &
$ \sqrt{a} \left( E - E_0 \right) $ &
$ \sqrt{-a} \left( F - F_0 \right) $ &
$ \sqrt{p} \left( D - D_0 \right) $ &
$ $ \\
\hline
time of flight &
$ t $ &
$ \frac{1}{n} M $ &
$ \sqrt{\frac{a^3}{\mu}} \left( E - e \sin E \right) $ &
$ \sqrt{\frac{-a^3}{\mu}} \left( e \sinh F - F \right) $ &
$ \sqrt{\frac{p^3}{\mu}} \left( \frac{1}{6} D^3 + \frac{1}{2} D \right) $ &
$ r_0 s c_1 + r_0 \dot{r_0} s^2 c_2 + \mu s^3 c_3 $ \\
radius &
$ r $ &
$ \frac{p}{1 + e \cos f} $ &
$ a \left( 1 - e \cos E \right) $ &
$ a \left( 1 - e \cosh F \right) $ &
$ q \left( D^2 + 1 \right) $ &
$ r_0 c_0 + r_0 \dot{r_0} s c_1 + \mu s^2 c_2 $ \\
radial velocity &
$ \dot{r} $ &
$ \sqrt{\frac{\mu}{p}} e \sin f $ &
$ \sqrt{\frac{\mu}{a}} \frac{e \sin E}{1 - e \cos E} $ &
$ \sqrt{\frac{\mu}{-a}} \frac{e \sinh F}{e \cosh F - 1} $ &
$ \sqrt{\frac{\mu}{p}} \frac{2 D}{D^2 + 1} $ &
$ $ \\
horizontal velocity &
$ r \dot{f} $ &
$ \sqrt{\frac{\mu}{p}} \left( 1 + e \cos f \right) $ &
$ \sqrt{\frac{\mu}{a}} \frac{\sqrt{1 - e^2}}{1 - e \cos E} $ &
$ \sqrt{\frac{\mu}{-a}} \frac{\sqrt{e^2 - 1}}{e \cosh F - 1} $ &
$ \sqrt{\frac{\mu}{p}} \frac{2}{D^2 + 1} $ &
$ $ \\
orbital speed &
$ v $ &
$ \sqrt{\frac{\mu}{p} \left( e^2 + 2 e \cos f + 1 \right) } $ &
$ \sqrt{\frac{\mu}{a} \frac{1 + e \cos E}{1 - e \cos E}}$ &
$ \sqrt{\frac{\mu}{-a} \frac{e \cosh F + 1}{e \cosh F - 1}} $ &
$ \sqrt{\frac{\mu}{p} \frac{4}{D^2 + 1}} $ &
$ $ \\
flight path angle &
$ \phi $ &
$ \tan \phi = \frac{\dot{r}}{r \dot{f}} = \frac{e \sin f}{1 + e \cos f} $ &
$ \tan \phi = \frac{e \sin E}{\sqrt{1 - e^2}} $ &
$ \tan \phi = \frac{e \sinh F}{\sqrt{e^2 - 1}} $ &
$ \tan \phi = D $ &
$ $ \\
\hline
position &
$x$ &
$ \frac{p \cos f}{1 - e \cos f} $ &
$ a \left( \cos E - e \right) $ &
$ a \left( \cosh F - e \right) $ &
$ q \left( 1 - D^2 \right) $ &
$ $ \\
&
$y$ &
$ \frac{p \sin f}{1 - e \cos f} $ &
$ b \sin E $ &
$ b \sinh F $ &
$ p D $ &
$ $ \\
velocity &
$ \dot{x} $ &
$ - \sqrt{\frac{p}{\mu}} \sin f $ &
$ \sqrt{\frac{\mu}{a^3}} \frac{-a \sin E}{1 - e \cos E} $ &
$ \sqrt{\frac{\mu}{- a^3}} \frac{a \sinh F}{e \cosh F - 1} $ &
$ \sqrt{\frac{\mu}{p}} \frac{-2 D}{D^2 + 1} $ &
$ $ \\
%&
%$ $ &
%$ $ &
%$ - \frac{1}{r} \sqrt{\mu a} \sin E $ &
%$ - \frac{1}{r} \sqrt{- \mu a} \sinh F $ &
%$ - \frac{1}{r} \sqrt{\mu p} D $ &
%$ $ \\
&
$ \dot{y} $ &
$ \sqrt{\frac{p}{\mu}} \left( e + \cos f \right) $ &
$ \sqrt{\frac{\mu}{a^3}} \frac{b \cos E}{1 - e \cos E} $ &
$ \sqrt{\frac{\mu}{- a^3}} \frac{b \cosh F}{e \cosh F - 1} $ &
$ \sqrt{\frac{\mu}{p}} \frac{2}{D^2 + 1} $ &
$ $ \\
%&
%$ $ &
%$ $ &
%$ \frac{1}{r} \sqrt{\mu a \left( 1 - e^2 \right) } \cos E $ &
%$ \frac{1}{r} \sqrt {- \mu a \left( e^2 - 1 \right) } \cosh F $ &
%$ \frac{1}{r} \sqrt {\mu p} $ &
%$ $ \\
\hline
f \& g functions &
$ f $ &
$ 1 - \frac{r}{p} \left( 1 - \cos \hat{f} \right) $ &
$ 1 - \frac{a}{r_0} \left( 1 - \cos \hat{E} \right) $ &
$ 1 - \frac{a}{r_0} \left( 1 - \cosh \hat{F} \right) $ &
$ 1 - \frac{q}{r_0} \hat{D}^2 $ &
$ 1 - \frac{\mu}{r_0} s^2 c_2 $ \\
&
$ g $ &
$ \frac{r r_0}{\sqrt{\mu p}} \sin \hat{f}$ &
$
\sqrt{\frac{a}{\mu}} r_0 \sin \hat{E} +
\frac{a r_0 \dot{r_0} \left(1 - \cos \hat{E} \right)}{\mu}
$ &
$
\sqrt{\frac{-a}{\mu}} r_0 \sinh \hat{F} +
\frac{a r_0 \dot{r_0} \left(1 - \cosh \hat{F} \right)}{\mu}
$ &
$
\sqrt{\frac{p}{\mu}} r_0 \hat{D} +
\frac{q r_0 \dot{r_0} \hat{D}^2}{\mu}
$ &
$ r_0 s c_1 + r_0 \dot{r_0} s^2 c_2 $ \\
&
&
&
$ \hat{t} - \sqrt{\frac{a^3}{\mu}} \left( \hat{E} - \sin \hat{E} \right) $ &
$ \hat{t} - \sqrt{\frac{-a^3}{\mu}} \left( \sinh \hat{F} - \hat{F} \right) $ &
$ \hat{t} - \sqrt{\frac{p^3}{\mu}} \frac{1}{6} \hat{D}^3 $ &
$ \hat{t} - \mu s^3 c_3 $ \\
&
$ \dot{f} $ &
$
\sqrt{\frac{\mu}{p}} \tan \frac{\hat{f}}{2}
\left( \frac{1 - \cos \hat{f}}{p} - \frac{1}{r} - \frac{1}{r_0} \right)
$ &
$ - \frac{\sqrt{\mu a}}{r r_0} \sin \hat{E} $ &
$ - \frac{\sqrt{- \mu a}}{r r_0} \sinh \hat{F} $ &
$ - \frac{\sqrt{\mu p}}{r r_0} \hat{D} $ &
$ - \frac{\mu}{r r_0} s c_1 $ \\
&
$ \dot{g} $ &
$ 1 - \frac{r_0}{p} \left( 1 - \cos \hat{f} \right) $ &
$ 1 - \frac{a}{r} \left( 1 - \cos \hat{E} \right) $ &
$ 1 - \frac{a}{r} \left( 1 - \cosh \hat{F} \right) $ &
$ 1 - \frac{q}{r} \hat{D}^2 $ &
$ 1 - \frac{\mu}{r} s^2 c_2 $ \\
\end{tabular}
\end{center}
\end{document}
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