It's amazing how short the core of Newton's law of gravity is:

theta = angle(sun.x,sun.y, sat.x, sat.y)
dist = distance(sun.x,sun.y, sat.x,sat.y)
accelx = K*cos(theta)/dist/dist
accely = K*sin(theta)/dist/dist
velx = velx + dt*accelx
vely = vely + dt*accely
posx = posx + velx
posy = posy + vely
plot(posx,posy)

This post is part of my Freewheeling Apps Devlog.

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