Gravitational Arcs in the Galaxy Cluster Abel 370

The SAM science verification program is finished in the January 2014 run. The picture below shows gravitational arcs in the galaxy cluster Abel 370 as seen by by the SDSS, HST, and SAM (from SV proposal by G.~Caminha et al.)

The FULL IMAGE shows an amazing picture where almost every source is a distant galaxy, partially resolved by SAM, and only few are stars. The dark shadow on the left is produced by the SAM guide probe wich used a guide star at the periphery of the science field (this is a region of low star density). Several gravitational arcs are seen in the image. Elongation of galaxies caused by the weak lensing is also noticeable. The images were taken on September 29, 2013 under non-optimal conditions and has a FWHM resolution of 0.5 arcsec. Five 5-min. exposures in the SDSS i' and r' filters were combined to produce the picture.