
Image credit: Convair
Image source: SDASM Archives

Image credit: Convair
Image source: SDASM Archives

Just for a lark, here’s the original finding aid:
Description: ARTISST CONCEPT OF UPGRADED CENTAUR Photographer: REQUESTER
That’s not super helpful, and knowing the paining was photographed in 1991 just tells me it’s pre-1992. The dual thrusters made me think of Centaur, and the uncrewed Shuttle-C in the bottom left corner gives some context. Either way, it’s a beautiful image and you didn’t come here for an education, you came here to look at pretty pictures of cool stuff. Right?
So, I think this is a shuttle-launched Centaur upper stage or ‘Shuttle-Centaur’ bound for lunar orbit. If you know otherwise, please do let me know. I read all the comments, and I super promise I won’t be offended.
Image credit: NASA Glenn
Image source: National Archives

Image credit: Convair
Image source: SDASM Archives

Image credit: Convair
Image source: SDASM Archives