Where's my celestial GPS -- Dark matter distorts the universe

This computer generated simulation image shows how dark matter, shown in red, distorts the light path from and apparent shape of distant galaxies, depicted in blue.

The presence of a massive network of distributed dark matter is evident in a recent analysis of the shapes of 200,000 distant galaxies. Scientists with the Canada-France-Hawaii Telescope believe that intervening dark matter, normally invisible, may distort images originating in the distant universe, much the way an old window distorts images originating on the other side. Makes you wonder how man would "aim" a spaceship, using light as its target, matter, or some other means.

No GPS's for space yet.

Source: NASA Astronomy Picture of the Day

http://apod.nasa.gov/apod/archivepix.html