Time-Resolved Spectroscopy Observation regarding Synthetic Uranus at High Pressure and Temperature

Icy giant planets, like Uranus and Neptune, are thought to consist of mixture of water, methane, and ammonia at high pressures and temperatures. In the 1980s the Voyager II mission revealed that both of Uranus and Neptune had unusual non-dipolar and non-axial magnetic fields. However, the cause of the magnetic fields is still a major unresolved issue in planetary science. It is necessary for solving this issue to better understand the behavior of the molecular mixture at the planetary interior conditions. We performed laser-shock experiments on molecular mixture samples to simulate the interior conditions of the planets in laboratory. The mixtures were shock-compressed up to \textasciitilde 80 GPa and 4500 K. We measured the self-emission spectra from the compressed samples. We here discuss the line spectra in the blue region by comparing the experiment with theory.