Guiding Light

Astronomers working on the Sloan Digital Sky Survey project, sponsored in part by the U of C, have discovered the most distant object ever identified--a quasar some 27 billion light years from Earth that will help scientists chart the birth and formation of galaxies, explore structure on the largest scales, and better understand black holes.

Quasars are compact, luminous objects powered by super-massive black holes. They are not a distinct class of objects but rather a phase that young galaxies go through when the black holes at their centers pull in surrounding matter at a high rate. The newly discovered quasar has a redshift of 5.8, which means that astronomers are seeing light that left its source when the universe was in its infancy, less than a billion years old.

The real value of the newly discovered quasar--and some 1,000 others identified by Sloan researchers--say scientists, is not their far-off locations but the sample's size and quality. Past quasar surveys have included a smaller, less uniform selection of objects. --Steve Koppes