The LHC was primarily designed as a particle discovery machine. It has already spotted the Higgs boson, and the hope is that its upgrade to higher energies will allow it to uncover more. But each LHC run is capped off by a period of experimentation that has as much to do with cosmology as particle physics.

Normally, the quarks and gluons that make up most of familiar matter come bundled in discrete packages like protons and neutrons. But increase the energy and density enough, and you reach conditions similar to those of the Universe a fraction of a second after the Big Bang. Here, the boundaries of these discrete particles break down, and something called a quark-gluon plasma forms.

Study of the quark-gluon plasma was pioneered at Brookhaven National Lab's Relativistic Heavy Ion Collider, or RHIC. There, gold atoms are stripped of their electrons and accelerated to high energies. When they collide, their protons and neutrons break down to form the plasma, and researchers can study it by tracking the particles that fly out of it.

Normally, CERN's Large Hadron Collider smashes individual protons together. But each year, CERN uses it as a giant version of RHIC by accelerating lead ions. Because lead ions have 82 protons, it's much easier to accelerate and steer them. As a result, the collisions are much higher energy; while the protons topped out at just under 14 Tera-electronVolts, the lead atoms will be colliding at over 1 Peta-electronVolt.

Or, rather, are colliding. CERN announced that data from the first lead ion collisions was obtained this morning, local time.

So far, at lower energies, the LHC has largely extended the discoveries made at RHIC. But there's always a chance that new behavior will become apparent at higher energies, and the upgraded LHC is definitely providing a big boost in the energy department.