The Cluster Lensing And Supernova survey with Hubble (CLASH) was a program on the Hubble Space Telescope to observe 25 massive galaxy clusters.
CLASH was one of three programs selected (along with CANDELS and PHAT) in the first class of Hubble multi-cycle treasury programs, which were designed to tackle large questions unanswerable through normal observations.
[2] CLASH was led by principal investigator Marc Postman, and had a science team of over 40 researchers.
Images were taken in 16 filters, which were selected to maximize the ability to detect distant galaxies behind each cluster.
[5][6] In 2013, one study utilizing CLASH data found that RX J1347.5-1145 had intense gravitational bending of light such that 8 images of the same object were detected.