JPL HORIZONS Node.js Client

Installation

npm i dude-where-is-my-planet --save

Usage

Running the below command in your terminal will give you state vectors for the Sun and Uranus system between 2001-01-01 and 2001-01-02 and save them to a json file called sunUranusSystem.

  fetch-bodies --bodies Sun  Uranus --center Sun --units AU-D --step "1 d" --start 2001-01-01 --stop 2001-01-02 --save sunUranusSystem

Your operating system does not support shebangs?

If your operating system does not support shebangs, you will simply have to run the fetch-bodies script the way you would any npm script, like so:

  npm run fetch-bodies -- --bodies Sun  Uranus --center Sun --units AU-D --step "1 d" --start 2001-01-01 --stop 2001-01-02 --save sunUranusSystem

The output of this query looks as follows:

  [  
    [  
        {  
          "name":"Sun (10)",
          "date":"A.D. 2001-Jan-01 00:00:00.0000",
          "x":0,
          "y":0,
          "z":0,
          "vx":0,
          "vy":0,
          "vz":0
        },
        {  
          "name":"Sun (10)",
          "date":"A.D. 2001-Jan-02 00:00:00.0000",
          "x":0,
          "y":0,
          "z":0,
          "vx":0,
          "vy":0,
          "vz":0
        }
    ],
    [  
        {  
          "name":"Uranus (799)",
          "date":"A.D. 2001-Jan-01 00:00:00.0000",
          "x":15.37333859361431,
          "y":-12.72455315994613,
          "z":-0.2465764556735673,
          "vx":0.002471951210373022,
          "vy":0.002849962182880889,
          "vz":-0.00002140958914339345
        },
        {  
          "name":"Uranus (799)",
          "date":"A.D. 2001-Jan-02 00:00:00.0000",
          "x":15.37581022685618,
          "y":-12.72170297083339,
          "z":-0.2465979327045777,
          "vx":0.002471267458614458,
          "vy":0.002850429686759978,
          "vz":-0.00002151936487289544
        }
    ]
  ]

Status

This project is a living one and feedback and contributions are very much welcome. To contribute, create a branch and issue a pull request. If you wrote unit tests for your code, that would be much appreciated.

Development

  npm start

This project uses husky and lint staged to make sure the code being commited passes all tests and make sure unformatted code does not get commited to the repository.

Build

  npm run tsc

Unit Tests

To run all unit tests, you can run the command below in your terminal.

  npm test

Credits

Credits go to the awesome people at JPL that made the HORIZONS system available to the public.