After reading the description of Mullane hypothesizing how the
Commander and Pilot of Challenger would have been making all efforts to
"restart" the blank systems and "fly" the orbiter, something seems to
have been missed. It seems that when the cabin seperated from the
payload bay, the aft cabin windows would have been exposed to day light
at that point (as they normally faced the darkend payload bay during
launch). That would have certainly provided a visibility to the crew
(look backwards) that no shuttle existed beyond those windows and
efforts were futile. Or do those windows have covers over them at
launch. Cant see a need for that though.