There is a website connected with NASA that puts out some amazing pictures. The Astronomy Picture Of The Day, or APOD, is one of my visits each day. Quite a few of those pictures ended up in the directory that my computers read for the desktop background rotator I run here.
They put together, each year, a calendar full of astronomical wonders. A link to the discussion on their page is here if you should like to read through all the wonderful geekiness.
If you aren't into all of that, a direct link to the calendar in PDF is here.
Furthermore, if you need a nice basis for a calendar of your own graphics and have access to Microsoft Publisher, they were kind enough to place a link to the .PUB file. You can then modify things as you wish.
Since there's a lot of black in space, you're going to need new printer cartridges or do what I do - refill them!