Sorry for the old thread but I found a solution for this on my pc.
If you're using an Nvidia card with Geforce Experience, it's possible that it's automatically enabled Muli-Frame Sampled AA (MFAA). MFAA is essentially MSAA but sampling from multiple frames instead of the single frame to improve performance and quality, this has the side effect of introducing ghosting at low framerates, causing the weird effect on loading screens.
To fix it, all you need to do is open your Nvidia Control Panel and go to Manage 3D Settings -> Program Settings, from there find KSP (you might have to manually add it) and turn MFAA off. When you next open the game you should be able to use anti-aliasing without any ghosting.