Exotic laser-produced high-energy-density (HED) plasmas akin to those found in stars and nuclear explosions could provide insight into events throughout the universe. Physicists have discovered a new way to measure and understand these plasmas, among the most extreme states of matter ever produced on Earth. Improved understanding could provide benefits ranging from fine-tuning the high-density plasmas in inertial confinement fusion experiments to better understanding of processes throughout the universe.