It Rains Diamonds on Uranus and Neptune

Scientists proved that Neptune and Uranus have rains of Diamonds

Far out in space, the ice giants Uranus and Neptune make their way around the sun. Under their gas envelope, the two outermost planets of our solar system could hide invaluable values: enormous amounts of diamonds, some of which are gigantic. At least that’s what new research results suggest.

Uranus and Neptune are similar in structure; both probably have a solid or liquid core under the gas envelope, which is surrounded by dense layers of ice – although this “ice” does not consist primarily of water, as on Earth, but of hydrocarbons, water and ammonia.

Neptune
Neptune has been the outermost planet in our solar system since Pluto was downgraded to a dwarf planet.

These hydrocarbon compounds, astrophysicists have long suspected, are split up inside the gas giants. The reason for this is the extreme pressures that prevail there – Uranus has 14 times the mass of the earth, the slightly smaller Neptune even 17 times. The carbon released by this process crystallizes into a diamond around 7000 kilometers below the surface.

uranus
Uranus is slightly larger than Neptune but has a lower mass.

Kilometer-Long Diamond

Over the millennia, these diamonds gradually sink into deeper layers – to a certain extent, it rains diamonds – and accumulate around the core. The structures made of the hardest material may be somewhat larger than what is found on earth: while the largest diamond ever found weighed a little over 3000 carats (that’s around 600 grams), those in the gas giants are likely to be several Be meters or even kilometers tall.

diamonds
The largest diamond ever found the Cullinan was discovered in South Africa in 1905. In its raw state, it weighed 3106.75 carats (621.35 g) but was split into 105 stones, including 9 large ones.

Until now, there has been no clear experimental evidence for all of this. This has now been achieved by a German-American team of researchers: Using the most powerful X-ray laser in the world, the scientists were able to simulate conditions inside the two gas planets. The researchers used the plastic polystyrene, which is made up of carbon and hydrogen atoms, as a model substance for the atmosphere of the gas planets.

Two Shock Waves

They exposed this material to two shock waves – the first was generated by an extremely powerful optical laser, the second by the X-ray laser. The shock waves generated a pressure of around 1.5 million bar and a temperature of 5000 degrees Celsius in polystyrene. Thanks to the laser, they were able to observe the splitting of hydrocarbon and the conversion of carbon into diamond crystals for the first time in snapshots.

linac
The most powerful X-ray laser in the world, the Linac Coherent Light Source (LCLS), is located in Stanford, USA.

“We were just amazing, surprised in the experiment that we get such a clear signal, and so a lot of diamond producing,” Dominik Kraus said of the Helmholtz Center Dresden-Rossendorf (HZDR). The experiments showed that almost all carbon atoms were united in nanometer-sized diamond structures, explained Kraus. The researchers published their results in the journal “Nature Astronomy”.

The knowledge of astrophysicists could also have practical uses in the production of artificial diamonds on Earth. Tiny diamonds such as those that they were able to produce with the laser are used in various areas – including cutting materials, in medicine, or in electronics. So far, they have mainly been produced using explosives, but the laser method could eventually make a more advantageous method possible.