Hugh rectangular object hovered over my home.

it was a clear night, I sensed something ( don't know what ) outside. Our hone faced south, and was on the north edge of town, with nothing but open fields to the east of us. I was in the family room, which was on the N.W. back side of the house. 
I arose from the couch, and went to the patio doors, which looked out to the north. I opened the sliding door and looked up, and saw a hugh object, which seemed to be hundreds of feet across, east to west, and was over our house. I could not see the south end of it, as it was beyond my field of vision. It covered , what seemed to be a few hundred feet to the north of the house. I was startled, and was torn between going back inside, upstairs to get my binoculars, and/or camera, to try and get some record, or to try to see it better. It had structure and there were lights on the bottom. It seemed so large, and yet it was moving so little that it may have been motionless. 
It was something that defied reason, nothing that large could be there, and be motionless, and make no noise. I watched it for , what seemed like minutes, and then made an attempt to go get something to make somekind of record with, a camera. I ran upstairs, searched for it, and the binoculars, scanning out the upstairs window, which faced north also, came back down, in a panic and saw it vanish. I searched the skies for over an hour, uping to get a glimpse of it again, but didn't. I was terribly dissappointed. I have never been able to forget this, I just had to tell someone. I'm not sure of the year, but we lived in this house from the fall of 1972, till the summer of 1976.
Witness indicates that date of sighting is approximate.  PD