NASA released some free space posters a couple of months back.
I think they have them up on their website, you should give them a look! I had them printed for a small fee and now they're up on my wall!
Yup. The poster files are free, you just have to get them printed somewhere. They have a few different themes. I got Europa, Trappist-1e, Mars Explorers Wanted and "We Need You"
Sweet! I hope you like them as much as I do!