Nuclear Pasta

Posted by Ellen

What we've got here is a greatly enlarged image of something that atoms do when they're really really really stressed out. How greatly enlarged is the picture? So greatly that to make it life-sized, you'd have to shrink it down till it reached just one-thousandth of the way across a medium-sized atom. That's so small that it would go unnoticed even by the most powerful electron microscope on earth–which is okay, because what's imaged here is strictly an extraterrestrial sort of thing.

What's pictured here develops only in the center of neutron stars–dying stars–where nuclear explosions have compressed what's left of the star's essence into a fiercely exploding little ball a few miles across and a trillion times as dense as lead. Under these conditions, atoms cannot maintain their normal structure and separate identity; their nuclei interact and fuse to form crazy little shapes called nuclear pasta.

We have a description of this pasta straight from the astrophysicists:

In the center of an exploding star, at a trillion times the density of lead, atomic nuclei interact and fuse to form complex shapes known as nuclear pasta.  This image is about 1/1000th of an Ångstrom–1/1000th of the radius of an atom–on a side and is based on a molecular dynamics simulation by Andre Schneider involving 51,200 protons and neutrons.   The complex shapes result from a competition between attractive nuclear and repulsive electric forces.  Nuclear pasta forms part of a neutron star, an object with the mass of the sun but only the size of a city.   These stars are the densest known objects before matter, as we know it, collapses into a black hole.  This large-scale computer simulation predicts properties of the nuclear pasta that may be important both for how neutron stars oscillate and for how some massive stars end their lives in giant explosions known as supernovae.