Scientists Predict Neptune’s Chemical Makeup

A new study sheds light on the chemical makeup of the planet.


Neptune is the eighth and farthest planet from the Sun in the Solar System. It has 17 times mass of Earth. As a gas giant (or ice giant), Neptune has no solid surface. In fact, the blue-green disc we have all seen in photographs over the years is actually a bit of an illusion.

But now, scientists have helped solve the mystery of what lies beneath the surface of Neptun. A new sun.

Neptune has an extremely low temperature. Thus it is known as one of the ice giants. Means, the chemicals on these distant worlds exist in a frozen state. Frozen mixtures of water, ammonia, and methane make up a thick layer of the planets‘ atmosphere and core known as the mantle, that is poorly understood.

Scientists noted, “However, studying the mantle is quite difficult. Thus, we used laboratory experiments to study these conditions. It is very hard to recreate the extreme pressures and temperatures found on ice giants.”

Scientists ran large-scale computer simulations of conditions in the mantle. They then observed the chemical reaction with each other at very high pressures and low temperatures. By doing this, they were able to predict which compounds are formed in the mantle.

They found that the frozen mixtures of water and ammonia inside Neptune form a little-studied compound called ammonia hemihydrate.

Dr. Andreas Hermann said, “Computer models are a great tool to study these extreme places, and we are now building on this study to get an even more complete picture of what goes on there.”

“The findings will influence how ice giants are studied in future and could help astronomers classify newly discovered planets as they look deeper into space.”

“It helps us better predict what is inside icy planets like Neptune or Neptune’s chemical makeup. Our findings suggest that ammonia hemihydrate could be an important component of the mantle in ice giants, and will help improve our understanding of these frozen worlds.”


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