BBCnews is carrying this report on what must be one of the most bizzare astronomical objects found to-date: a natural particle accelerator some 20 light-years across. Found using the European XMM-Newton x-ray space telescope, this ring was discovered when scientists made observations of the Arches Cluster, a star-forming region close to the Milky Way's centre. It's not clear if the object is in the cluster, or just happens to be on the same sight line. Not surprisingly, scientists have no idea how such an object could have formed, but it seems to be pumping out high-energy particles with energies in excess of a thousand trillion volts.

You know, I'd stop saying "just when you thought it couldn't get any weirder", but it wouldn't make any difference.