Bright white light within a white haze

Our dog became agitated and barked as if there were someone outside or a car approaching. I took the dog out and noticed a very large light in the North, North west position. The light was slowly moving southward approx. 500 feet altitude while emitting no sound. I went to the house to alert my wife and she came outside to view it. When she saw it, she wondered if it was the moon shrouded in a mist. But, it was a clear night, with the starts all visible, and it wasn't the moon. We both witnessed the object slowly move to the West. The hazy light surrounding the object grew larger, and then it disappeared as we watched. We have many military transport aircraft near us and it did not resemble any of them nor did it flash any navigation lights or make any sound.