CL2244-02 Galaxy Cluster with gravitational arcs
May 16, 2005
This photo is a colour composite image of the galaxy cluster CL2244-02 (redshift z = 0.3), combining a 20 min jittered ISAAC Ks (2.16Âµm) exposure with 15 min V (green-yellow) and R (red) exposures, obtained with the VLT Test Camera at the UT1 Nasmyth focus. In addition to the prominent blue arc, produced by gravitational lensing of a galaxy at redshift z = 2.24, there are also notable, very red arcs, both closer to the centre and further out. They were only detected in the infrared image and are probably due to lensing of a much more distant galaxy.
Topics: Gravitational lens, Gravitational lensing, Astrophysics, Galaxy groups and clusters, Weak gravitational lensing, Large-scale structure of the cosmos, Redshift, Galaxy, Very Large Telescope