Weak Lensing Distorts the Universe
Is the distant universe really what it appears to be?
Astronomers hope not.
Intervening
dark matter, which is normally invisible,
might show its presence by
distorting images
originating in the
distant universe,
much the way an
old window distorts images originating on the other side.
By noting the degree to which background galaxies appear
unusually flat and
unusually similar to neighbors, the
dark matter distribution producing these weak
gravitational lensing distortions can be estimated.
Recently released
analysis of the shapes of 200,000 distant
galaxies imaged with the
Canada-France-Hawaii Telescope
(CFHT) does indicate the presence of a massive network of
distributed dark matter.
Future
results may even be able to discern
details of the distribution.
The
above 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.