is there a key the the orrey in the arcane university ? If so where do i find it? hope some one can help

The orrey in the base game is locked, and there is no key for it. However it is used in the Orrey DLC. Using the Console on PC to unlock it leads you to an empty room.

No. Access is blocked unless you have installed the Orrery official downloadable content (DLC) package and completed the associated quest. More info here: http://www.uesp.net/wiki/Oblivion:Official_Plug-ins

Edit: Oops. The Rolling Lizard and I both posted at the same time.

ty for the assistance !