You may have encountered the claim in various “Did You Know?” compilations that it rains diamonds on Saturn. A reader recently asked whether this is true and, if so, why it happens. Let’s address this right away: yes, it’s very likely that such a phenomenon as diamond rain can occur on Saturn (as well as other gas giant planets).
Let’s delve into why this happens.
Saturn’s atmosphere is composed of 96.3% hydrogen and 3.2% helium. The remaining 0.5% consists mainly of hydrocarbons: methane, ammonia, ethane, and so on. Moreover, the upper layers of Saturn’s atmosphere contain many hydrocarbon clouds — meanwhile, some of the strongest storms in the Solar System rage on Saturn. Wind speeds can reach up to 1120 mph (1800 km/h).
When lightning occurs in an ammonia-methane storm, the hydrocarbons that come into contact with the lightning bolt break down, releasing free carbon. In the conditions of Saturn’s upper atmosphere, this carbon will be in a solid state. Essentially, this would be mere soot.
