Left work shortly after 2pm Sunday, 3/24 going home to Granbury,Tx. from Stephenville. I take the back roads instead of Hiway 377, the commonly used route because of heavy traffic on 377, for safety reasons. I was on CR305 close to the Erath/Hood county line. A very rural area and sparsely populated. Almost no traffic. About 1420hrs a very bright silver light to the south caught my eye. It appeared round but was so bright it was hard to tell. I appeared to be about a mile away, at 5000' above ground, stationary. I stopped my car and watched it for about one minute then it shot away almost directly away from me to the south so I lost sight in less than a second. I have been a licensed pilot for 45 years and this was no known aircraft. This was a sunny clear day so the brightmess was really remarkable. I do not believe it was a reflection, again because of the level of brightness so that the light appeared to be eminating fron the object. I was very interested and curious, I was not frightened. /