Flying disc with bright light

Audible rumble from night sky, coming from above, behind sighters who were in an open field on a semi moonlit frigid February night about to sled. A very large disk shaped object 50-100 ft diameter suddenly came into view nearly directly above from behind. Traveled roughly in west to east direction. Bright green light in center underneath. Noticeable rumble sound. Unfamiliar sound. Disturbingly unfamiliar rumble sound…not a helicopter, not a plain. Object moved in slow floating motion overhead to front of viewers. Extremely bright came on directly beneath object. As a vertical beam of light projecting from object to the ground, scanning movement. Shape of beam rectangular. Viewers in beam momentarily, nearly blinding brightness. Overwhelming eeriness prior to, during sighting turning into fear during and after. Object with beam of light continued moving slowly with beam falling on the open snow and ice covered field which includes farmland, fencing. And a large electrical transmission line. Object slowly moved eastward then faded from view but more of a disappearance then actually flying off or traveling off into the distance. Object just disappears slowly within a half mile a way or so. Viewers so frightened they ran back to home… which was about 150 yards from house.