orbits

For my uncle Zbys who watched the planets and stars.

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Types and functions for dealing with Kepler orbits.

The main data type is Orbit, which describes the path of a body in orbit.

Nomenclature

Symbol	Meaning	Notes
a	Semi-major axis	Negative for hyperbolic orbits
b	Semi-minor axis	Negative for hyperbolic orbits
e	Eccentricity
q	Periapsis
i	Inclination
μ	Standard gravitational parameter
Ω	Longitude of the ascending node
l	Semi-latus Rectum
n	Mean motion
p	Period
t	Time since periapse
M	Mean anomaly
E	Eccentric anomaly	Only for elliptic orbits
H	Hyperbolic anomaly	Only for hyperbolic orbits
ν	True anomaly
h	Specific angular momentum
ε	Specific orbital energy
εp	Specific potential energy
εk	Specific kinetic energy
v	Orbital speed or velocity
r	The radius to the orbiting body
φ	Flight path angle

Note that in the Haskell source uppercase symbols such as Ω and M are written with a leading underscore.

Implementation

This package makes use of the units package to ensure that the implementation is correct regarding units of measure.

Contributing

Contributions and bug reports are welcome!

Please feel free to contact me on GitHub or as "jophish" on freenode.

-Joe