The rate at which the light moves across the room is related to the size of the windows through which the sun is passing. I see people claiming that it is impossible for the sunlight to pass that quickly and stating that it takes "15 minutes." There is no recorded time it takes sunlight to pass. It's dependent on many things: time of year, time of day window size etc. the chances of that being the sun are so much greater than an apparition. All it will take is another day before we know. Unless the window is covered