A basic 3-body Planetary System

December 24, 2010

Hi folks, as a continuation to the previous tutorial here is a 3-body planetary model where the solution to the equations is contained in a static form, as a lookup table (I previously called it a “pure spreadsheet solution”). The model is static in the sense that after any parameter is changed, the solution data remains unchanged in a table until a new parameter is updated by the user. The display is dynamic however since an “Offset()” function…


How to Model a Basic 2-body Planetary System

December 23, 2010

Here is a tutorial explaining how to model a two dimensional  2-body planetary system in Excel. It uses the Euler method of integration. The tutorial starts with explaining the simple newtonial laws acting on the two planets. There are essentially just two forces acting on each body at any time: the inertia and the gravitational attraction. During each small time step, from the distance between bodies we can calculate the gravitational…


Day and Night Over the Atlantic – an example of sprite animation

December 22, 2010

Hi guys, here is an animation I made yesterday by downloading 120 pictures of the Earth taken 12 minutes apart by satelites above the equator at 30 degrees longitude west on 10/01/2010. The pictures are 500 x 500 pixels and they are pasted as a background of a chart by a slimmed down VBA macro. You can change the speed of the model. The time increment is fixed however at 12 minutes…


Roller Coaster

September 20, 2010

A roller coaster in Exel 2003 in 3-dimension (perspective view). To start de ride after download, click the little sun icon in the NE corner of the chart. Most of the calculations are done in the spreadsheet with very little VBA as a “glue”. The display is created on a plain 2D scatter plot.