# Space Age Given an age in seconds, calculate how old someone would be on: - Earth: orbital period 365.25 Earth days, or 31557600 seconds - Mercury: orbital period 0.2408467 Earth years - Venus: orbital period 0.61519726 Earth years - Mars: orbital period 1.8808158 Earth years - Jupiter: orbital period 11.862615 Earth years - Saturn: orbital period 29.447498 Earth years - Uranus: orbital period 84.016846 Earth years - Neptune: orbital period 164.79132 Earth years So if you were told someone were 1,000,000,000 seconds old, you should be able to say that they're 31 Earth-years old. If you're wondering why Pluto didn't make the cut, go watch [this youtube video](http://www.youtube.com/watch?v=Z_2gbGXzFbs). ## Hints In this exercise, we provided the definition of the [algebric data type](http://learnyouahaskell.com/making-our-own-types-and-typeclasses) named `Planet`. You need to implement the `ageOn` function, that calculates how many years old someone would be on a `Planet`, given an age in seconds. Your can use the provided signature if you are unsure about the types, but don't let it restrict your creativity: ```haskell ageOn :: Planet -> Float -> Float ``` ## Getting Started For installation and learning resources, refer to the [exercism help page](http://exercism.io/languages/haskell). ## Running the tests To run the test suite, execute the following command: ```bash stack test ``` #### If you get an error message like this... ``` No .cabal file found in directory ``` You are probably running an old stack version and need to upgrade it. #### Otherwise, if you get an error message like this... ``` No compiler found, expected minor version match with... Try running "stack setup" to install the correct GHC... ``` Just do as it says and it will download and install the correct compiler version: ```bash stack setup ``` ## Running *GHCi* If you want to play with your solution in GHCi, just run the command: ```bash stack ghci ``` ## Feedback, Issues, Pull Requests The [exercism/haskell](https://github.com/exercism/haskell) repository on GitHub is the home for all of the Haskell exercises. If you have feedback about an exercise, or want to help implementing a new one, head over there and create an issue. We'll do our best to help you! ## Source Partially inspired by Chapter 1 in Chris Pine's online Learn to Program tutorial. [http://pine.fm/LearnToProgram/?Chapter=01](http://pine.fm/LearnToProgram/?Chapter=01) ## Submitting Incomplete Solutions It's possible to submit an incomplete solution so you can see how others have completed the exercise.