[amsat-bb] question about the Space Station

Hi All:I observed the Space Station pass over this location(Hopkinton,RI) a couple of nights ago.The sky was relatively clear at the time.However,I observed a slight wobble( >.05 degrees ) as it passed from NNW to SSE.I have observed multiple Space Shuttle passes and I have never observed any wobbles in its orbit.Is the Space Station having any troubles with its gyroscopes?Could atmospheric conditions or the way it reflects sunlight explain my observation?Comments welcome!