I'm at an all day meeting, not nearly as fun as SUSY06, but one of those things where you are locked in a windowless room all day with endless discussion about the future of particle physics. I'm sitting in the middle of a gang of astrophysicists, so I have pleasant company and can enjoy discussions during our breaks. Speaking of breaks, we could use a pleasant one on this blog right now, so I've asked each of my astro colleagues for their favorite pretty astronomy picture. Here are the results: The Horsehead Nebula (taken taken with the NOAO Mosaic CCD camera on the 0.9-meter telescope located at Kitt Peak National Observatory near Tucson, AZ.):
The Sombrero Galaxy (taken by the Hubble Space Telescope in 2003):
The galaxy cluster Abell 1689 (taken by the Hubble Space Telescope)
This last one is a spectacular example of gravitational lensing. The arc-like pattern spread across the picture like a spider web is an illusion caused by the gravitational field of the cluster. The cluster is so massive and compact that light rays passing through it are deflected by its gravitational field, much as an optical lens bends light to form an image. The process magnifies, brightens and distorts images of objects that lie far beyond the cluster and makes very faint and distant objects visible. The universe is amazing, isn't it! Thanks to my colleagues Andy Albrecht (UCDavis), Bill Carithers (LBNL), and Steve Ritz (NASA-Goddard)!!
