As "shootist" suggests, there is an incongruous juxtaposition here of then and now. It is also an example of scale incongruity -- small man, suspended in a cold and empty world. The huge black window is the key to an image. A black hole in the middle of an image is normally a divisive element, summoning the eye at the expense of everything else. It works for you here, however, because it suggests the ether -- the place where the electronic sounds from his cell phone go as he speaks. His conversation is being sucked into space by this black hole, and will miraculously re-emerge in somebody else's ear.
