1) i had just picked up my son's mother from work at wal-mart in south sioux city, nebraska. it was after dusk and we were driving on hwy 35 heading west approaching the intersection with hwy 110 on our way to emerson nebraska to pick up our son. 2) when we were still approximately 1 mile away from the intersection, my son's mother noticed an object sitting motionless above the church that sits at the sw corner of the intersection. local people at that time called the church "twin churches". 3) we had no idea what the object was as we approached the church. it was not at all like anything we had ever seen before. the darker red/purple lights coming from the corners and underside of the triangular object were not similar to anything we had noticed on any aircraft previously, or since that incident. 4) we were about 100 feet from the object at our closest point. it appeared to be about 10-20 feet above the tree-line. it was getting dark outside and the object looked very dark or black and did not reflect any light. it was horozintal to the horizon, motionless, and emitted no noticeable sounds or vibrations. the lights it was emitting did not appear to change color or intensity. best guess in size in relation to near objects would be less than 50ft but more than 30ft across with height close to 10ft. 5) i was anxious and the lights and unuasual nature of the ufo caused an uncomfortable feeling. my son's mother was extremely scared and began crying and screaming when i attempted to pull over to the side of the road near the other half-dozen vehicles that had stopped to investigate the object. she was terrified and her reactions kept me from coming to a complete stop. i kept my speed at 5 to 10 mph as we drove away from the church. we were extremely rattled and shaking. she refused to travel on that road after dusk for several years after this happened. 6) i maintained a slow speed and monitored the ufo for a couple more miles until the area became hidden from view. the object appeared to remain motionless and unchanging throughout this entire time.