They were a series of books published in the 1970s in which sci-fi art from the time was collected and turned into a bit of a story. They were all supposed to be handbooks put out by the "Terran Trade Authority", documenting a fictitious war that took place between 2000 and 2100 AD. In any case, the art was quite lovely, and had a distinctive look. Your piece is completely original, of course, but I like the style; it has a bit of that TTA feel, even if it was completely unintentional