Reflective spherical object on or above my car going with the flow and then took off with now noise and no lights.

My wife and I were on our way home to Winslow. She was pregnant and ready to give birth any day. As we were driving in the country, I noticed something above our car hovering or sitting on the roof. I leaned forward and saw a reflective spherical object just outside my windshield like it was sitting on my car. I would speed up and it stayed with us. My wife, who I am divorced from now saw the same thing. When we came to a large hill that dipped down, it flew away from the drivers side and continued to the horizon with no noise and no lights. This shook me up for days and I haven't said anything about this until today.
Date may be approximate.  PD