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Deep within our planet, an enduring enigma continues to intrigue scientists: Earth’s inner core.

Comprised primarily of iron and nickel, this intensely hot, solid sphere is roughly 70% the size of our moon.

A recent study suggested that the core has reversed its rotation, and now, researchers have discovered another surprising revelation—the shape of the inner core is undergoing change.

By analyzing seismic waves produced by powerful earthquakes, scientists inferred that the inner core is gradually deforming. However, there’s no need for concern—this transformation doesn’t pose any direct threat to life on Earth.

Over time, alterations in the core’s structure could influence our planet’s magnetic field, which not only shields Earth from solar radiation but also plays a crucial role in guiding the migration of numerous animal species.

Secrets of the Ocean

Loggerhead sea turtles are renowned for their incredible migrations spanning vast oceanic distances. But how do they navigate with such precision in a seemingly limitless expanse of water?

These remarkable creatures possess an innate ability to sense Earth’s magnetic field, utilizing it in two distinct ways: they follow a magnetic “map” to determine their location, and they rely on a magnetic compass to orient themselves in the right direction.

A groundbreaking study now reveals another layer to their navigational prowess—loggerheads appear to memorize magnetic fields associated with locations where they previously found food.

In a fascinating display, young captive turtles have been observed executing a unique “dance” in response to familiar magnetic cues linked to past meals. This charming behavior must be seen to be fully appreciated.

Breaking Free from Gravity

Astronauts Butch Wilmore and Suni Williams, who journeyed to the International Space Station aboard Boeing’s Starliner on its inaugural crewed test mission in June, may return to Earth sooner than originally planned. NASA is currently aiming for their reentry as early as mid-March.

Meanwhile, at NASA headquarters, concerns have emerged in response to policy shifts under the Trump administration affecting diversity, equity, inclusion, and accessibility communications.

Despite industry uncertainties, the agency reaffirmed the importance of the Space Launch System megarocket—first launched in 2022—to the Artemis program, America’s ambitious plan to return astronauts to the moon. Yet, Boeing has announced layoffs related to this project.

Additionally, Jeff Bezos' Blue Origin announced it will be reducing its workforce by more than 1,000 employees, just weeks after successfully unveiling its first orbital rocket, New Glenn.

Mysteries of the Universe

In a surprising twist, astronomers detected the highest-energy "ghost particle" ever identified, not in deep space, but deep beneath the Mediterranean Sea.

For over a decade, the KM3NeT Collaboration has been constructing an elaborate underwater neutrino detection system off the coasts of France and Italy. Neutrinos—nearly massless particles capable of passing through matter unimpeded—carry vital information about the universe's most extreme events, such as gamma-ray bursts.

One particularly powerful neutrino interacted with the unfinished ARCA detector near Italy, emitting a flash of bluish light. Scientists are now tracing its origins, hoping to uncover the violent cosmic event that propelled it toward Earth.

In a separate discovery, the Euclid space telescope captured a remarkably detailed image of a rare celestial formation known as an Einstein ring—where the light from a distant galaxy bends perfectly around a closer one, creating a luminous, circular illusion.

Echoes from the Distant Past

An analysis of ancient human remains unearthed in a Polish cave near Kraków suggests that early Europeans may have consumed the brains of their enemies.

Researchers examined the bones of 10 individuals from the Magdalenian culture, a prehistoric society that thrived in Europe between 11,000 and 17,000 years ago. Cut marks on the skulls indicate the removal of brain matter and marrow.

Previous studies suggest cannibalism was part of Magdalenian funerary customs. However, in this particular instance, archaeologist Francesc Marginedas of the Catalan Institute of Human Paleoecology and Social Evolution stated that the evidence points instead to acts of warfare.

Strange Wonders of Nature

Speaking of brains, researchers have identified a parasitic fungus that manipulates cave-dwelling spiders, turning them into so-called "zombies."

This strange discovery was first made by a documentary crew filming inside an abandoned gunpowder storage facility at Castle Espie Wetland Centre in Northern Ireland in 2021, when they noticed an orb-weaver spider exhibiting bizarre, unnatural movements.

The fungus, named Gibellula attenboroughii, infects and kills its spider hosts, then utilizes their bodies to propagate its spores. Though scientists know the fungus alters spider behavior, they are still investigating the precise mechanisms it uses to take control of its hosts.

New Discoveries

Take a moment to explore these fascinating findings:

• Astronomers detected a colossal radio jet—the largest of its kind ever observed in the distant cosmos—dating back to the universe’s infancy.
• New data indicates that unprovoked shark attacks worldwide have seen a significant decline in 2024, leaving experts puzzled as they search for explanations.
• Archaeologists uncovered the remains of an ancient Roman basilica beneath a high-rise building in London, shedding light on the city’s distant past.
• The James Webb Space Telescope is gearing up to closely observe asteroid 2024 YR4, assessing whether the space rock poses a genuine threat of colliding with Earth in 2032.

Intrigued? There’s always more to explore. Sign up here for the next edition of Wonder Theory, where CNN Space and Science journalists Ashley Strickland, Katie Hunt, and Jackie Wattles continue uncovering wonders from the far reaches of the universe to the depths of Earth's history.