Weak Lensing Distorts the Universe
Credit: S. Colombi (IAP), CFHT Team
Posted on 03/30/2008 4:13:24 PM PDT by sig226
Explanation: 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. 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.
About 10% of the hiss between radio stations on your AM band is due to the cosmic background radiation.
I didn't know that. Fascinating. I have tinnitus and need to listen to a radio or white noise just so I can sleep. Sometimes I'll just listen to the white noise on AM. Now I can think about the fact that I'm listening to cosmic noise of the universe. That's cool.
Also, the planet Jupiter contributes significantly. That noise would be greater when Jupiter is ‘up,’ but I don’t know if a casual radio listener would be able to tell the difference.
God’s “Aquarium”?
btt
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.