I was trying to put two big meshes in a scene when this happened
I dont really understand this 
Don’t understand your question. If one object is in front of the other… it’s positioned there. Use more than one color as well
This happened to me in Maya when i was using PNG textures, i forgot to remove the transparency on the material, i probably forgot to not make the png transparent, didnt remove the alpha channel. Maybe its something similar.
My objects are very big and the spaceship is far from them. I use origin rebasing for precision stuff, but this strange problem happens. When I am close to my objects, they are where they should be, but when I get far away, this happens… I think it has something to do with camera limits but I don’t know how to fix it
Thanks for your answer 
But I dont use textures here, it’s a giant sphere object that has a Constant3Vector applied to the base color of the material.
When I am close to the spheres, I see them fine, with thel being where they should be. The problem happens when I fly really far away from the objects. I use orogin rebasing to keepe my pawn in the center.
Are you using opaque or translucent materials?
No, I don’t. These are the most basic materials which don’t have textures.