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Using the Electric Orrery

The Electric Orrery has a number of controls for changing the simulation. You can change the date, look at different parts of the Solar System and animate, both forwards and backwards in time. This is all done with the buttons on the right hand side of the Orrery (see the image on the left here).

Changing the Date

This section shows the date for the simulation (as "Day/Month/Year"). You can type in a new date and press Update to move to a new time. You can go back to today by clicking on the Today button. You can look at any day from 1900 to 2100 AD.

Different Planets

Because the Solar System is a very large place, you cannot see all of it on one view - the dwarf planet Pluto is 100 times further away from the Sun than Mercury. The Field of View buttons let you choose which planets you want to see.


By clicking on the buttons in the Animate section, you can go both forwards and backwards in time. There are three buttons for going forward at different speeds:

  • > - Go forward one day at a time.
  • >> - One month at a time.
  • >>> - One year at a time
The other three buttons go at the same speeds but back in time. You can stop the animation at any time by pressing the Stop button. The animation will stop itself if it tries to go back in time before 1900 or forward in time past 2100.

The Key

The Key shows you which planet is which on the screen. You can find out more about each of the classical planets and the dwarf planet Pluto from the Solar System section of the Astronomy section. Note that the sizes of the orbits of the planets are to scale, the planets themselves are not.