Hubble is not immobile. Hubble can use gyros and magnetic torquers to reorient itself. Hubble doesn't have thrusters, so in that sense it can't change orbits or anything.
I suppose you could call anything man-made in space a spacecraft, it doesn't matter if it has turbo-ion rocket jets or not. And it's just a matter of sophistication. What about the TOOLBAG? It had an independent orbit. Or was that space debris?
What about Echo-1 ?? Was that a spacecraft? A Satellite?
What about a space colony like an O'Neill cylinder? It is not termed a spacecraft, though it is like Hubble and cannot move. But if you put rocket motors on it, now what? We have a generational ship?
What about the Viking One? Is that a spacecraft? It doesn't go anyplace once landed. Does it cease becoming a spacecraft and now become a lander?
What about the ALSEP mirrors the Apollo guys left behind? It doesn't go anyplace either? Those mirrors had the Saturn V rocket as main propulsion, did they not? So they had engines, and they also borrowed the LM RCS too!
Does a spacecraft start out as something else then become one later on? Or does a spacecraft start out as a spacecraft and become something else, like a lander? or like a satellite?
And also what is the difference between a spacecraft and a spaceship? I understand spacecraft are smaller than spaceships. Or spaceships are manned and spacecraft are not? What size do we switch naming conventions? I fear we're arguing semantics now.
---------- Post added at 02:25 AM ---------- Previous post was at 02:08 AM ----------
An engineer once told me that a space-a-craft is something that can carry something. Like the framework of a satellite carrying the electronics bus and relay components, for example.
Or a suit carrying the astronaut, or a shuttle carrying cargo.
A spacecraft can carry cargo or men.
A spaceship carries living things, specifically, it is designed for men, it has seats, more or less.. You don't have an un-manned spaceship, you have an abandoned spaceship, and empty spaceship, un-manned craft, derelict.
If a spacecraft is un-manned, then it could be on a temporary basis, like crew transfer.
A spaceship supposedly needs a crew to function. A craft can function with or without crew.