A bright blue-white light that hovered for almost an hour then quickly zoomed away.

I saw a bright, blue-white light in the west about 15 or so above the horizon. I watched it for about 15 to 20 minutes (maybe for a half hour), then awakened my parents.  My mother got up, but my father refused to.  My mother and I watched the object for perhaps another 15 to 20 minutes.  The object did not move for all of that time.  Finally, the object zoomed away to the north or north-west, first dipping "down" maybe 5 degrees and then turning "up" at a sharp angle, disappearing in less than one second.
Date is approximate.  PD