I heard a very loud hellicopter and was looking for it behind the trees. It appeared with a whiteball very close in front of it. It looked like a star.

The hellicopter was very very close to the star like object.  They were going hellicopter speed (slow) and the hellicopter was staying right on its tail (weird close like when the blue angles fly close together).  They were going north to south.  It was not another helicopter or plane just a star looking object being escorted or chased.  The helliopter had all its lights on.   I have only heard a hellecopter  that loud once before during the day and they were huge hellicopters.  
We don't usully get helicopter flying around here very often never at night.  
My neighbor heard it to from her bedroom and thought it was weird.  
It was a little overcast full moon but a bright sky.  Kinda light outside.