Compiled by | Wang Zhaoyu
In the universe, the sky of ice giants may be filled with diamonds. Compressed carbides can turn into diamonds at temperatures that researchers had not previously considered, potentially making "diamond rain" a common phenomenon on ice giants. The related research was published on January 8th in Nature Astronomy.In the past, laboratory experiments have puzzled researchers about the conditions under which diamonds are formed in the interiors of ice giants such as Uranus and Neptune. There are two types of experiments used to study this issue: dynamic compression experiments, where carbides are subjected to sudden impact, and static compression experiments, where carbides are gradually compressed in a chamber. So far, dynamic compression experiments have required higher temperatures and greater pressures to form diamonds.Mungo Frost and colleagues from the SLAC National Accelerator Laboratory in the United States conducted a new set of experiments using static compression and dynamic heating. They sandwiched polystyrene between two diamonds and compressed it by bombarding it with X-ray pulses.The researchers observed that polystyrene began forming diamonds at a temperature of approximately 2200°C and a pressure of 19 gigapascals, conditions similar to the shallow interiors of Uranus and Neptune.This pressure is much lower than the pressure required for diamond formation in previous dynamic compression experiments, and the reaction time is longer than in typical dynamic compression experiments, which may explain why such experiments have not produced low-pressure diamonds.Frost said, "It is inconsistent with established results, and not what we expected to see, but it brings everything together. It turns out that it's all due to different time scales."This discovery could mean that "diamond rain" may also exist on smaller planets than previously thought. According to the researchers' calculations, out of the approximately 5,600 confirmed exoplanets, over 1,900 may experience "diamond rain".This also suggests that diamond formation in the solar system may occur at shallower depths than we imagined, which could change our understanding of the dynamics inside gas giants. These shallower layers may cause "diamond rain" to pass through a layer of ice as it sinks toward the center of the planet, which in turn would affect the planet's magnetic field, a complex phenomenon that is still poorly understood.Related Paper Information:
https://doi.org/10.1038/s41550-023-02147-x
China Science News (2024-01-10 Edition 2 International, originally titled "Take You to Experience the "Diamond Rain")Editor | Ji HongmeiLayout | Jiang ZhihaiPlease scan the QR code below for 3 seconds to recognize
