A bright oval object, 50 to 75 feet in diameter, moved horizontally, stopped, and then descended behind a small nearby bluff.

The large bright glowing oval object moved silently parallel to the ground, just above and beyond the top of a tree covered shale bluff on the other side of a small river we were camping at. The object lit up the area as if it were early dawn, tree frogs became earily silent.
When the object was directly in front of my tent opening, it stopped for perhaps 4 or 5 seconds and then decended steadily in at a 45 degree angle behind the shale bluff. The light then suddenly went out at about the time one might have expected it to have "landed" on the other side of the bluff. The light did not fade out, but went off as if someone had flipped a switch.
The size of the object is difficult to determine, but gauging from the the size of the trees in the area and the short distance to the bluff, I would estimate it as being somewhere between 50 to 75 feet across. It did not change shape or color during the 2 full minutes of this slow moving event.
Witness indicates that date is approximate.  PD