My knowledge of science is very basic, but after some research I have some knowledge, but I am still not clear with so many things regarding to this earth. 

I have read [Laser's Measure the Earth's Rotation and Wobble][1] but would appreciate it if anyone who knows science well, could explain how the rotation of the Earth is measured and how it is affected by the Chandler wobble and the annual wobble? 


  [1]: http://www.livescience.com/17619-lasers-measure-earth-rotation-wobble.html