Orbit Simulation logic I'm building an Orbit Simulator (this is what I build every time I learn a new language). I'm looking for the pseudocode for calculating the acceleration. I know the formula: G*m/(d2-d1)^2, I'm trying to figure out why I'd need the hypotenuse. You see, I can calculate the accelX and accelY just from the x and y coords. Then I can udpate the x and y velocities, then I can update the x and y positions. Nowhere do I actually need to calculate the hypotenuse. But this yields incorrect motion. So, am I supposed to 1] calculate the hypotenuse from the x/y coords, 2] then figure out the acceleration as a single scalar value along the hypotenuse 3] then immediately reconvert the single scalar acceleration back into accX/accY?