# The passing of FiftyOneFifty

It is with deep sadness we announce that another of our hosts and friends Donald Grier, known to us as FiftyOneFifty, has passed away.

FiftyOneFifty's frat brother Randy Hall has written an lovely piece. The team at Linuxlugcast are preparing our own tribute if you want to contribute an audio file you can email Honkeymagoo or join the show.

Our thoughts go out to his friends and family at this difficult time.

# hpr2598 :: Calculating planetary orbits in Haskell

### tuturto talks about calculating planetary orbits

Hosted by tuturto on 2018-07-18 is flagged as Clean and is released under a CC-BY-SA license.
Listen in ogg, spx, or mp3 format. | Comments (0)

### Part of the series: Haskell

A series looking into the Haskell (programming language)

Function signatures (it might or might not be helpful to have these at hand while listening):

• Helpers:
radToDeg :: Floating a => a -> a
degToRad :: Floating a => a -> a
clamp :: Float -> Float
• Time:

day :: Int -> Int -> Int -> Float -> Day Float
• Orbital parameters:
longitudeOfAscendingNode :: Orbit body center => body -> center -> Day d -> LongAscNode body center
inclinationToEcliptic :: Orbit body center => body -> center -> Day d -> InclToEcl body center
argumentOfPeriapsis :: Orbit body center => body -> center -> Day d -> ArgPeri body center
semiMajorAxis :: Orbit body center => body -> center -> Day d -> SemiMajor body center
eccentricity :: Orbit body center => body -> center -> Day d -> Ecc body center
meanAnomaly :: Orbit body center => body -> center -> Day d -> MeanAno body center
• Calculating location on orbital plane:
eccAnomaly :: MeanAno a b -> Ecc a b -> EccAnomaly a b
trueAnomaly :: EccAnomaly a b -> Ecc a b -> TrueAnomaly a b
dist :: EccAnomaly a b -> Ecc a b -> SemiMajor a b -> Distance a b
• Translating between coordinate systems:
toEclCoord :: TrueAnomaly a b -> Distance a b -> LongAscNode a b -> ArgPeri a b -> InclToEcl a b -> EclCoord a b
toEqCoordinates :: EclCoord body Earth -> Day Float -> EqCoord body