Except that 3rd Officer would be 4th in command, traditionally (using civil aviation terminology, which seems appropriate given that the Nostromo is a civilian spacecraft). The second-in-command is the First Officer (after the Captain/Pilot in command), with the Second Officer and Third Officer after him.lastbesthope said:I'd peg her as 3rd in Command, hence 3rd officer.
Alternately, it might be a role analogous to this one, which does seem to vaguely fit Ripley's job during the movie...
All this is reminding me that I haven't seen Alien recently or frequently enough. I will have to rectify this problem.