I would guess they are contained in the same general 'Starbase' class in the coding, but with a movement speed set to 0... But just remember, it isn't sideways. There is no up or down in space, so while it is not oriented with the game's arbitrarily decided 'up' plane, it isn't really sideways.

Technicly, whatever direction it is pointing could be considered up, since it likely has artificial gravity onboard, making whatever direct it points, up.

I find this really annoying as Vasari as I used to use Vasari SB with Frontal Deflector Shield to charge through enemy minefields and kill heaps of mines at once. Now the Vasari SB leans out of the way. So annoying. I can no longer use this tactic. Why?