Strange light in the southern sky (Oklahoma, 1988).

I remember the date of this sighting because it was the day before my grandmother died.
 It was around ten o'clock at night (I don't recall the exact time),and I stepped outside our house (I was 19 at the time) south of Stonewall, Oklahoma, and looked up at the southwestern sky.  There on the horizon (high enough that it wasn't anything land based) was a large (larger and lower than the stars) whitish-amber light, "sitting" perfectly still.  I had lived at this location all my life then, and had never seen anything like this light before.
 For about a minute or more, the light was perfectly still, and then it started moving slowly eastward.  Over the course of probably two minutes it moved from the southwestern sky to the southeastern quadrant of the sky.  Then it stopped and remained stationary for perhaps two or three more minutes, whereupon it simply went out, as if someone had flipped a switch and turned it off.
 Over the period of perhaps the next three years, I saw something similar to this sighting perhaps three more times.  Once my mother (now deceased) witnessed it with me, and another time my brother did.  Neither of them had any idea of what it was, either.