It looked like a full-size simulator to me. Programs like these often create full-size mock-ups/simulators which look just like the real thing but aren't functional or are only used for training. It's also easier to take photos of them.
The NASA caption never mentioned anything about the photo actually being from the shuttle in space, so this is my guess as to what really happened.
The NASA caption never mentioned anything about the photo actually being from the shuttle in space, so this is my guess as to what really happened.