This image (larger version) shows a three-dimensional model of an aneurysm in a human patient. An aneurysm is a ballooning of an artery at a weak point (see Physics in Your World). The model was made of latex, inflated with a liquid, and photographed in polarized light. For the physics of aneurysms, see Danger of Aneurysms (scroll down to the bottom) from Hyperphysics.