I came to this conclusion both by watching my videotape of the ep, and by viewing several pics the Wolf 359 research has brought out, most notably a pic of the Nebula model Marcus Nee originally sent to Bernd, but that I have also.

Here is where the Nebula class Melbourne appears: As the Saratoga's escape pod jettisons, you can see both the Borg ship and the Saratoga. Up in the right hand corner of the screen, however, is a mysterious, stand-alone saucer wreckage. A lot of people had differing ideas as to just what ship that saucer represented. Some thought it was the U.S.S. Gage, others (like Frank Gerratana) thought it was the Excelsior class Melbourne because of a statement made in a DS9 making-of book. Well, Frank was right, but not about the model itself-it's the Nebula class study that was originally battle damaged by Okuda & Sternbach.

Get a good look at the wreckage. The Nebula is actually upside-down in the shot. My screencaps were kinda small and poor quality, but with continually viewing the scene on a big TV, plus with Markus' pic, I confirmed that the saucer's battle damage matches between the two. There are also two proturbances that you can see jutting out at the left end of the saucer. Again, using the upside-down perspective, the pylon attached to the rear end of the Nebula saucer (with the tiny 1/2500 nacelles) is visible as the lower, larger proturbance. The other, smaller proturbance is part of one of the larger nacelle's pylons.

The saucer is turned at more of an angle than its original appearance in BoBW, but it is the same model. So the DS9 book Frank refers to was correct by saying the wreckage was the Melbourne...just not the one everyone thought it was.

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Me: "Why don't you live in Hong Kong?"
Rachel Roberts: "Hong Kong? Nah. Oh, but we can live in China! Yeah, China has great Chinese food!"

We know for a fact that some of the "BoBW" models were still available for photography when "Emissary" was shot - as per the DS9 Companion and Okuda's comments on the Legato quote in that book. The damaged Nebula study model could very well be among these models in theory. And its presence would not only provide continuity between the episodes, but would indeed keep the issue open for a "how many Melbournes" debate so that there would be multiple correct answers.

And the damage patterns on the models are so darn close to identical that I'm 99% sure you made the correct conclusions here. What we thought was shadowing of a TOS movie style saucer inboard of the distinctive flat outer rim is in fact a deep chasm in a lenticular TNG-style hull just inboard of a standard tapering rim.

There is one major difference between the "BoBW" study nebula and the "Emissary" ship, though. The former has the port main nacelle still attached, as we can see in the shots taken from a distance, nearly directly above the ship. The latter does not seem to have any main nacelles visible, even though the port side is turned towards us. One can of course argue that the nacelle went missing during the time the model was in storage - but one can hardly argue that the "real" ship was missing a nacelle when the Saratoga exploded, but had regained it when the E-D arrived!

Or am I (not) seeing things? Is the nacelle there in the "Emissary" picture or not?