If hyperspace is a fifth dimension, why would Han to worry about flying into a star are too close to a supernova?
This is why official canon is dumb. Just go by what you see on the screen.
Well, for what it’s worth, Starwars.com provides this explanation:
“Hyperdrives allow starships to travel faster than the speed of light, crossing space through the alternate dimension of hyperspace. Large objects in normal space cast “mass shadows” in hyperspace, so hyperspace jumps must be precisely calculated to avoid collisions.”