Ok, so I'm having a friendly debate with a friend who is a total Treknobabble geek, but in this case I think he is wrong. Here we go:
Warp Drive: when you are travelling at warp, are you actually moving through physical space (i.e. subject to smashing into a planet if you don't have a good navigator - his position) or are you in a bubble of real-space that moves through sub-space (and therefore don't need to worry about hitting a planet - my position).
Now all I've found so far on-line indicates that yes, you ARE in a bubble of real space (which moves with you, thus preventing time dialation issues) but nothing I've found seems to indicate if you are moving at superluminal velocity in REAL space, or through subspace.
He points out the need for a navigational deflector, but my point is that you DO need that for impulse drive (since you're moving near the speed of light in real-space, you want to keep things from hitting you), but that it really isn't necessary at warp velocities. He says it would be at warp speed, because again, to his understandnig you are just moving through real-space.
So - discuss, and if possible provide evidence/links for your contentions so I can have some ammo, or be proven wrong, either way.
With that out of that way, when you are warp you are in a subspace bubble, not totally in the normal spacetime continuum itself. However, a large physical object's gravity affects subspace so when a ship enters the gravity well, the ship is pulled out of warp and smashes into the large physical object at warp speeds. So, the navigator doesn't avoid the large physical objects, but rather the gravity wells they have.
As for the deflector dish, it used for both sublight and warp speeds to deflect dust, asteroids, and tribbles in the ship's path.
this is perhaps a little beyond me but if you were to take the fact that its meant to be real. it is as far as we can tell impossible to go faster than the speed of light, yet warp 9 is dozens or hundreds of times faster.
the first problem is sub space is not real but lets sort of pretend it is
im not sure what relation sub space has to warp drive. i believe sub space is only for communications.
once you hit warp i dont think the ship is even moving, but space that is changing around you by being pinched and distorted in front of the ship to reduce the distance and being thrown out behind the ship, sort of like a treadmill
but you are still in normal space. if a planet is in front of you you will still crash into it. your not being taken out of normal space just manipulating it to achieve impossible speeds
not sure if that is how the show describes it or if that even helps
From what I understand, Warp is the warping of space time, by making localized gravitational distortion to the actual Space-time fabric contracting it infront of you and expanding it behind you, almost like riding a wave. I am not quite clear on the details after this, as it is all theory, but I am pretty sure that normal matter is also distorted in this field, allowing a ship to warp through a star or a rock, but you don't have to take my word for it... Da Dun Da Da
Without looking into the "science" of it here are some of my thoughts.
1. In Generations Data mentions a ship making a course change due to a star going supernova, that could be because of the gravity thing though.
2. In "Way of the Warrior" Sisko has the Defiant drop out of warp due to a debris field which would have had a negligible gravitational effect on the ship, which would seem to indicate to at least some degree you are in physical space.