Effects to make space seem far away

I have a system where a camera rotates around the Earth. There is a separate icosphere with a space texture (from nasa) placed in the inside acting as a background. The problem is that it doesn’t seem “far” away enough. Placing the background further away is both a performance issue but also doesn’t make the texture look noticibly different.

In order to get a sense of scale that space is very far away is there any effects I can employ, or is it a fault of my texture?

Take a look in kerbal space program, if is something that you want. They have some tech articles that explain how to use 2 cameras to draw near and far away objects.