Check out NASA's cool new Hubble image in the last post. Louise Riofrio has a post
about it. The astro-ph paper is here
. They use both weak and strong lensing to find the mass distribution of CL0024+17. Matti, I think this paper has enough information for you to do a Bohr orbit analysis. If this is a typical head-on view of a recent collision of cluster systems, there must be an awful
lot of 'dark matter' in the cosmos. And they say one can't test quantum gravity with simple optical observations!
Meanwhile, Tommaso shows us
how QCD triumphs once again with B hadron lifetimes. And Carl Brannen
has updated his gravity equations