Help figuring the Net Tidal Force.?

Question

Hi there, I need to actually find the sum or the Resultant Direction of the force applied to Earth taking all planets out to Saturn considered. Is there a way for Excel to do this?

Answer 1

Excel can handle it, although it may not be able to give you satisfaction on the resultant you seek, since the Moon and Sun overshadow all the others. In fact, the probable error in solar or lunar tidal forces may well be greater than the magnitudes of the others.

You will either have to download a heliocentric ephemeris, or make a lot of simplifying assumptions (chiefly circular orbits) and generate your own for each planet. Since the synodic period of Jupiter and Saturn is about 20 years, you will need to cover at least 20 years with your model. Next come the distance calculations and the calculation of F and ∆F across the Earth's diameter for each body. For calculating resultants you need to calculate geocentric angles from some reference to each body. Finally come the vector additions.

Excel can do it, but you need a very large spreadsheet and a lot of determination.