Why Does It Rain Diamonds on Neptune? It is the only planet in our solar system that can’t be seen with the naked eye. Neptune was also the only planet predicted to exist by mathematicians before it was ever actually seen.
Today, though, people know more about Neptune than ever before. In 1981, scientist Marvin Ross predicted that the planet had diamond rain. He said both ice giants (Neptune and Uranus) may experience this phenomenon. In 2020, an experiment proved it could happen.
To carry out this experiment, researchers at Stanford University modeled the conditions on Neptune inside their lab. They started by applying extreme heat and pressure to polystyrene. Then, they sent shock-waves through the material using a laser.
Using x-rays, they watched what happened. The elements that make up polystyrene split from each other. This resulted in carbon and hydrogen atoms. Under pressure, the carbon turned into diamonds before their eyes. Based on these findings, the researchers believe it’s likely that diamonds do indeed rain down on the planet Neptune.
Experts have learned quite a bit about this planet since its discovery in 1846. On Neptune, a year lasts 60,190 Earth days. However, the farthest planet from the Sun experiences shorter days than we do on Earth. Neptune completes a full rotation once every 16 hours.
Just how far is Neptune from the Sun? About 2.8 billion miles! In fact, the planet is sometimes farther from the Sun than Pluto is. That’s one reason why human beings have such a hard time studying the planet. It’s difficult to get there! Only one spacecraft, Voyager 2, has visited Neptune.
Neptune has five rings and 14 moons to keep it company. However, the planet is not capable of supporting life as we know it. Although diamonds on Earth are rare, extraterrestrial diamonds (diamonds formed outside of Earth) are very common.
Diamonds so tiny that they contain only about 2000 carbon atoms are abundant in meteorites and some of them formed in stars before the Solar System existed. High pressure experiments suggest large amounts of diamonds are formed from methane on the ice giant planets Uranus and Neptune, while some planets in other planetary systems may be almost pure diamond.
Content for this question contributed by Tony Kimmel, resident of Conemaugh, Cambria County, Pennsylvania, USA