Scientists from Lawrence Livermore National Laboratory (LLNL), Sandia National Laboratories (SNL), and the University of Hyogo in Kobe, Japan, have developed a way to more precisely measure high-pressure compression in the laboratory up to 10 million atmospheres. LLNL said pressures exceeding 1 million atmospheres can alter how atoms are packed together, which can lead to new chemical bonding. Testing the quantum theory of condensed matter under enormous pressure has produced such discoveries as helium rain, a transparent sodium metal, superionic water ice, and the transformation of hydrogen into a metallic fluid. But, until now, most extremely high-pressure experiments â as much as 1 terapascal, or approximately 10 million atmospheres â relied on theoretical models or extrapolation of low-pressure measurements to determine just how much pressure was being applied.