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Earth’s core could house a reservoir of hydrogen equivalent to 45 oceans, according to study

Estrutura central da Terra, nucleo
Estrutura central da Terra, nucleo - Vadim Sadovski/shutterstock.com

A new scientific discovery promises to completely reshape the understanding of the internal composition of our planet and the origin of volatile elements essential for life. Pesquisadores identified that the core of Terra may contain vast reservoirs of hydrogen, with an estimated volume that varies between 9 and 45 times the amount of water present in all the oceans on the Earth’s surface combined. The conclusions were obtained from advanced experiments that simulated the extreme pressure and temperature conditions that exist in the center of the globe.

The data indicate that this hydrogen is not in the form of liquid water, but rather dissolved in the metallic alloys that make up the core. Estima This element represents 0.07% to 0.36% of the total mass of the central region of the planet. Essa concentration, although it appears small in percentage terms, translates into a colossal amount of matter on a planetary scale, suggesting that the interior of Terra is much richer in light elements than previous geological models proposed.

The study corroborates a crucial theory about planetary formation that occurred around 4.5 billion years ago. Evidence suggests that water and hydrogen were incorporated into the planet during the early stages of its formation, while Terra was still accumulating mass and differentiating its layers. Isso contradicts the hypothesis that most of the water would have arrived later, brought by impacts from comets and asteroids during the period known as late bombardment.

Simulation of extreme conditions in the laboratory

To achieve these results, the team of scientists used high-pressure chambers to recreate the hostile environment of the Earth’s core. In Nessas simulations, the behavior of hydrogen and silicon was analyzed when subjected to gigantic compressions, similar to those that occur thousands of kilometers deep. The objective was to observe how these elements interact with iron, the main component of the nucleus.

The tests revealed that, under these specific conditions, hydrogen tends to dissolve easily in the cast iron and remains “trapped” in the resulting mineral structure. Esse dissolution process creates stable compounds that trap the element deep within, preventing it from escaping into the mantle or crust. The methodology made it possible to calculate the core’s storage capacity without the need for direct collection of physical samples, which is impossible with current technology.

The research used a comparative approach to validate the data, establishing different saturation scenarios:

– The conservative scenario projects an amount of hydrogen equivalent to nine global oceans.

– The maximum saturation scenario suggests a volume corresponding to 45 oceans.

– The variation directly depends on the proportion of other light elements, such as silicon, present in the metallic mixture.

– The final density observed in the simulations coincides with current seismological readings of the core of Terra.

Impact on geological and magnetic evolution

The massive presence of hydrogen in the core has direct consequences for the internal dynamics of the planet and for the generation of the Earth’s magnetic field. The outer core, composed of metals in liquid state, moves generating electrical currents which, in turn, create the magnetic shield that protects the Terra from solar radiation. The introduction of light elements such as hydrogen changes the density and viscosity of this fluid, influencing the efficiency and stability of this natural geodynamo.

Furthermore, convection movements in the Earth’s mantle, responsible for plate tectonics and volcanism, receive thermal and chemical inputs from the core. The thermodynamics of the deep interior is affected by the presence of hydrogen, which can facilitate the release of waste heat and keep the core active longer than if it were composed of pure iron and nickel alone. Essa dynamics reinforces the view that the water and volatile cycle in Terra is an integrated system that connects the surface to deeper layers.

Long-time seismological observations already indicated that the core of Terra was slightly less dense than a sphere of pure iron should be. Esse phenomenon, called “density deficit”, intrigued geophysicists. Confirming that hydrogen acts as a major alloying element offers an elegant solution to this mystery, filling in the gaps in currently accepted density models.

Differences between surface and deep reservoirs

It is essential to distinguish the nature of the hydrogen found on the surface from that stored in the core. Nos oceans, hydrogen is linked to water molecules forming oxygen (H2O) in a liquid state. In the core, it exists in a metallic state or dissolved in minerals under pressures exceeding millions of atmospheres. Não is a navigable underground ocean, but an atomic reserve integrated into the rocky and metallic matrix.

Scientists compare this discovery to other known reservoirs in the mantle, where minerals such as ringwoodite have the ability to retain water in their crystalline structure. However, the potential volume of the core far exceeds the reserves of the mantle, consolidating the central region as the largest hydrogen deposit on the planet. Estudos Futures will seek to refine these estimates using new seismological techniques to more accurately map density anomalies.

The validation of the “wet Earth” model since its formation changes the perspective on planetary habitability. If water is an ingredient that integrates into the core during the formation of rocky planets, it is possible that exoplanets in other solar systems also possess vast internal reserves of hydrogen, which could influence their atmospheres and the potential to sustain life over billions of geological years.

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