/orbit x y z r d
X: The X of the point you're rotating. If you want to orbit a brick, use [ID].getPosition().
Y: The Y of the point you're rotating. If you want to orbit a brick, use [ID].getPosition().
Z: The Z of the point you're rotating. If you set this to zero you get wierd drifting on Slate maps.
R: The rotation around the point. It starts at 0 North and goes 360 degrees around to your left (clockwise as seen from above the object.) Decimals work too and are recommended with large structures.
D: The distance from the point. This will never be vertical; it is a distance from the XYZ point the direction of which is defined by the R.
Thus, /orbit 100 -60 0.5 43 4 will put you 4 Torque Units away from Torque Unit point {100, -60, 0.5} at 43° clockwise of due north (relative to the point), or 47° counterclockwise of due east (relative to the point).
EDIT: You can get the ID of the brick on any server you are admin on by looking at it and using /getid. This is a default command.