I wanted to calculate the position of planets in the solar system for a specific date in my past.

NASA’s Horizons System was the solution. Here is the setup for my future reference.

  1. Ephemeris Type: Vector Table
  2. Target Body: planet
  3. Coordinate Centre: Solar System Barycentre (SSB) [500]
  4. Time Specification: single day range
  5. Table Settings: defaults

I then used the X/Y coordinates plugged into a script which graphed the locations for me.