SDSSJ0946+1006 is an unusual gravitational lens system consisting of three galaxies at distances of respectively three, six, and eleven billion light years from Earth. In a report presented at the 211th meeting of the American Astronomical Society, researchers Raphael Gavazzi and Tommaso Treu of the University of California, Santa Barbara described the discovery of a double Einstein ring produced by the gravitational lensing of light from two distant galaxies. The observations were made using the Hubble Space Telescope.
The main lens lies at redshift z = 0.222, with the inner ring at z = 0.609 with an Einstein radius RE = ±0.01"1.43 and magnitude m = ±0.00619.784, the outer ring is at z ≲ 6.9 with RE = ±0.02"2.07 and magnitude m = ±0.0923.68 The lensing galaxy is also known as SDSSJ0946+1006 L1, with the nearer lensed galaxy as SDSSJ0946+1006 S1, and the farther lensed galaxy SDSSJ0946+1006 S2.
- arXiv preprint: "The Sloan Lens ACS Survey. VI: Discovery and Analysis of a Double Einstein Ring". (1.08 MB) 2-Feb-2008
- HubbleSite Hubble Finds Double Einstein Ring January 10, 2008 10:00 AM (EST)