The "window" is a joke for us pathetic SSE nerds who spent months researching the mysteries of 180top aka the planeterium at the top of Spaceship Earth.
From 1982 until 1994 the planeterium featured a simple, but effective "space station" scene. As you headed down backwards , the area that currently houses the floating news screen and floating digital classroom, are in the space formerly occupied by the space station.
The space station was a simple white painted set, with a few white and pink lights, as well as some blinking lights. It had walls and an overhang ceiling.
A satelite with an astronaunt was within the space station, while another astronaut with a piece of the satelite was outside the space station.
As you headed down backwards, slightly behind you was a window, with a light on, and a little girl was looking out of it to see the astronauts. She moved her head, and even waved to them.
In 1994, when Spaceship Earth was being refurbished, there was no use found for the space station. Both astronauts were removed, and the satelite dish as well as the satelite dish piece were all removed. Also removed were the lights in the space station. The space station itself was painted over black. The window however, a large 3Dimensional object sticking out of the wall, was kept in place due to a lack of budget and time to remove it. The animatronic girl was taken out of the window, her parts used for god only knows what, and the window was boarded up and painted black.
Now that SSE is going to be refurbished again, we have to wonder what will become of the space station scene, and if it will ever be used again. If the rescent comment is true that siemens recently removed the window, all we need to have is a new flash picture to see if it is there for not.