By using lasers, researchers have managed to compress diamond to 50 million times atmospheric pressure. This will let them study the conditions inside gas giants and how such planets evolve with time.
The largest planets in our solar system are gas giants. They are massive bodies consisting of gas with no solid ground underneath their thick clouds. For the first time, scientists at the National Ignition Facility at Lawrence Livermore National Laboratory have re-created the conditions deep inside these planets. The research appears in the July issue of the journal Nature.
The experiment could answer some important questions about gas giants, which are otherwise difficult to study due to the overwhelming pressures and temperatures inside. The closest anyone has gotten to studying the actual inside of a gas giant was in 1995, when NASA’s Gallileo probe descended 156km into the atmosphere of Jupiter before it was crushed by the atmosphere.
The researchers will now be able to study material properties in the giants and measure how they evolve with time. In particular, the research group is focusing on carbon, the fourth most abundant element in the universe (by mass). Carbon is an important element for planets both within and outside the solar system.
Using 192 lasers, teams from the Laboratory, University of California, Berkeley and Princeton University managed to compress a carbon sample to 50 million times the pressure of Earth’s atmosphere, similar to the pressures you’d expect at the center of Jupiter and Saturn. The carbon used in the experiment was in the form of a diamond that was vaporized by the lasers in 10 billionths of a second.
The researchers used 192 lasers to compress the sample.
While similar pressures have been achieved before, they’ve required shockwaves and immense temperatures. The new experiment can achieve such pressures at room temperature. “The experimental techniques developed here provide a new capability to experimentally reproduce pressure-temperature conditions deep in planetary interiors,” said Ray Smith, lead author of the paper. The technical challenge of keeping temperatures low was accomplished by tuning how the laser intensity varies with time.
“This new ability to explore matter at atomic scale pressures, where extrapolations of earlier shock and static data become unreliable, provides new constraints for dense matter theories and planet evolution models,” said Rip Collins another researcher on the team. The data from the research will be able to confirm some of the earliest predictions made by quantum mechanics at the beginning of the 20th century.