I don't think it's obvious from a simple Google search why a material capable of explaining things about galactic orbits and large scale gravitational effects c

I don't think it's obvious from a simple Google search why a material capable of explaining things about galactic orbits and large scale gravitational effects can't also explain localized orbital effects. There's no clear distinction in kind of effect, only scale. Perhaps instead of not contributing (by shouting RTFM when there isn't a manual for beginns on that topic), you could give a basic summary of why that's the case. If it's so simple, please outline in a line or two why dark matter can only impact large scale orbits (eg, galactic or bigger), and not cause localized or small scale effects (eg, solar system sized).