Indeed, I am not overly familiar with vectors, at least not to the level of complexity that's being used here. I suppose the problem comes with bridging the gap between physics and computing, and translating some of these equations into computer code. This is why I'm not simulating 2D space - the last time I tried that, most of even the most basic equations stopped working, like v = sqrt(GM(2/r - 1/a)). Still not entirely sure why. However, I could try using actual 2D space with a co-ordinate system again if you think it'll work, since I have the code for it stored elsewhere. I could then start using vectors properly, but yes, a lot of it would need explaining in simpler terms. I believe a lot of my problems came from the fact that I was simulating the actual force of gravity on my object and just letting it go from there - leaving me with no way of accurately figuring out the apoapsis, periapsis, period and so on. So, I would rather avoid using 2D space and vectors if possible but if there is no other way I should be able to get it set up.