Celestial Nebula low quality background textures

The nebulae that move in the background look rather blurry, as if you took an image and upscaled it; at least on a 4K monitor. Any chance these textures could be freshened up a little bit?

Not sure if these screenshots help much, but I think it's quite obvious. The problem isn't huge, it's more of a mild annoyance, but it could definitely be improved.

First image is next to other stuff, for example the stash looks substantially more crisp, as do leaves and flowers.