Journey to the Center of the Earth - a project to explore the core of our planet

Scientists have long sought to delve into the mysteries of Earth's interior, which remains largely unknown. In a recent article published in Nature, California Institute of Technology planetary scientist Dave Stevenson outlines an ambitious project to send a probe to our planet's core. The probe, immersed in molten iron, would provide valuable information about the temperature and structure of the Earth's deep layers. While this idea may seem futuristic, it could significantly benefit our understanding of not only our planet but also the processes occurring in other celestial bodies.

What does the interior of our planet look like?

In the novel "Journey to the Center of the Earth," a scientist traveling in Iceland and his nephew descend into a crater and visit an inner realm of a sunless sea and ancient civilizations. While Jules Verne's subterranean world certainly doesn't exist, much of Earth's interior remains a mystery. Hoping to contribute to the study of our planet's movements, the scientist planned a quest to journey to its heart.

In a paper published this week in Nature, California Institute of Technology planetary scientist Dave Stevenson outlined his plan to send a probe to Earth's core. Immersed in a blanket of molten iron, the probe, immersed in the core, would transmit information on temperature and structure, along with other readings.

The probe and the molten iron would find their way into the Earth's interior through a crack, perhaps created by a controlled explosion. To accommodate the necessary millions of tons of iron, the crack would have to be several hundred meters long and about 12 inches (30 centimeters) wide. The gravity and incredible weight of the iron would cause the crack to deepen, eventually reaching the core at a depth of 3,000 kilometers (1,800 miles) a few days later.According to Stevenson, this iron-blast combination offers more advantages than drilling. " You just have to set everything up once, and the crack will grow on its own ," Stevenson explained. This is fundamentally different from drilling, where the material gets harder and harder—and ultimately hardest—the further you go.

The probe, about the size of a grapefruit, would have to withstand enormous pressure and high temperatures. Furthermore, because radio waves cannot be transmitted through Earth, the data would have to be reflected by low-intensity mechanical waves.

Although no practical designs have been presented, Stevenson estimates the cost of such a mission to be comparable to the high cost of an unmanned planetary mission. Considering the revenues spent on exploring other planets and the limited knowledge of Earth, Stevenson feels it would be a worthwhile endeavor. Scientists don't know the precise temperature or composition of the core and its surroundings, so finding an independent probe observing the Earth's deep layers could rival the observations from successful missions to other planets.

We spend over $10 billion on unmanned missions to other planets, but we only know our own planet to a depth of 10 kilometers , says Stevenson. " When we visit other worlds, we're often surprised by what we find there, and I think the same will be true when we go [down into Earth's depths].

Realizing that many might react to this idea as if it were science fiction, Stevenson titled his dissertation "A Modest Proposal," borrowing the title from a satirical essay by Irish writer Jonathan Swift. While his proposal isn't as outlandish as Swift's (which suggested that the Irish eat their children during tough economic times), Stevenson acknowledges an element of fantasy in his work.

Ninety-five percent of the scientists who read the article might laugh at it as a pleasant read , Stevenson said, but I will be happy if they seriously consider the purpose of exploring the Earth's core.