Giant impactor Theia formed in the inner Solar System

Summary author: Walter Beckwith

2025-11-20

(Press-News.org) By tracking the isotopic fingerprints of iron in lunar and terrestrial rocks, researchers trying to understand the origin of the Moon’s mysterious progenitor add evidence to the idea that it came from the inner Solar System. According to the findings, Theia – the Mars-sized planetary body that collided with Earth to form the Moon – was born possibly closer to the Sun than to Earth. The Moon is believed to have formed when Theia collided with early Earth roughly a hundred million years after the formation of the Solar System. Most models of this process suggest that the Moon is mostly composed of materials derived from this ancient impactor. If Theia had a different isotopic makeup from Earth, it would be expected that the Moon would as well. Such isotopic variations can reveal where a planetary body originated in the Solar System, which could provide insight into the origin of Theia. However, analyses of lunar rock show that the Moon and Earth are nearly identical in their isotopic compositions for many elements. Although competing models have attempted to explain this similarity, the absence of clear isotopic differences and uncertainty over which processes caused this have made it challenging to determine where Theia originally formed. Here, Timo Hopp and colleagues conducted new high-precision iron isotope analyses of lunar samples, terrestrial rocks, and meteorites representing the isotopic reservoirs from which Theia and proto-Earth might have formed. According to the analysis, Earth and the Moon have indistinguishable iron isotopic compositions and both fall within that of non-carbonaceous meteorites, which are thought to represent material formed in the inner Solar System. Integrating these results with previous isotopic data for other elements and performing mass balance calculations for Theia and proto-Earth, Hopp et al. conclude that Theia likely originated in the inner Solar System and formed even closer to the Sun than proto-Earth.

END

ELSE PRESS RELEASES FROM THIS DATE:

Rebalancing lung repair with immune damage is key to surviving severe influenza

2025-11-20

Recovery from deadly influenza infection may hinge on helping the lungs heal in addition to stopping the virus, according to a new study in mice, which shows that pairing modest antiviral therapies with immune modulation can restore damaged tissues and lung function, even after severe infection has taken hold. The findings offer a foundation for future clinical strategies to improve outcomes in severe acute respiratory disease once standard treatments are no longer sufficient. Despite the availability of vaccines and antiviral ...

2025 Santorini seismic unrest triggered by “pumping” magma flow

2025-11-20

The massive swarm of earthquakes that rattled the Greek islands of Santorini and Amorgos in 2025 was not caused by a slipping fault – it was triggered by pulses of magma tunneling far below the seafloor, according to a new study. The findings offer a detailed look at a “pumping” magmatic dike in action and provide a foundation for more reliable, physics-based eruption forecasting and volcanic hazard assessment. In early 2025, a burst of intense earthquakes – including several around magnitude 5 – shook the region between the islands of Santorini and Amorgos in the Aegean Sea. Because Santorini is an active volcano with a history of catastrophic eruptions, ...

Toxic gut bacteria may drive ulcerative colitis by killing protective immune cells

2025-11-20

A toxin-secreting gut bacterium may fuel ulcerative colitis by killing protective immune cells that maintain intestinal homeostasis, according to a new study. The findings suggest potential for new treatment strategies. Ulcerative colitis (UC) is a chronic inflammatory bowel disease affecting millions of people worldwide in which the body’s immune system attacks the digestive tract, often causing severe and recurring symptoms, including abdominal pain, diarrhea, and intestinal bleeding. Although the underlying causes of UC remain ...

Rethinking where language comes from

2025-11-20

A new Science paper challenges the idea that language stems from a single evolutionary root. Instead, it proposes that our ability to communicate evolved through the interaction of biology and culture, and involves multiple capacities, each with different evolutionary histories. The framework unites discoveries across disciplines to explain how the ability to learn to speak, develop grammar, and share meaning converged to create complex communication. For centuries, philosophers and scientists have wrestled with understanding how human language came about. Language defines us as ...

Subverting plasmids to combat antibiotic resistance

2025-11-20

Researchers in the Blavatnik Institute at Harvard Medical School have just opened a new window into understanding the development of antibiotic resistance in bacteria. The work not only reveals principles of evolutionary biology but also suggests a new strategy to combat the antibiotic resistance crisis, which kills an estimated 1.3 million people per year worldwide. Findings, supported in part by federal funding, are published Nov. 20 in Science. Members of the labs of Michael Baym, associate professor ...

Theia and Earth were neighbors

2025-11-20

About 4.5 billion years ago, the most momentous event in the history of our planet occurred: a huge celestial body called Theia collided with the young Earth. How the collision unfolded and what exactly happened afterwards has not been conclusively clarified. What is certain, however, is that the size, composition, and orbit of the Earth changed as a result – and that the impact marked the birth of our constant companion in space, the Moon. What kind of body was it that so dramatically altered the course of our planet's ...

Calcium “waves” shape flies’ eyes

2025-11-20

For just a few hours, shimmering waves of calcium move through cells in the developing eyes of fruit flies. These spontaneous waves serve a purpose, enabling communication between cells and shaping the eye structure, according to a new study published in Science. Scientists have long observed waves of calcium during the development of the visual system in humans and other mammals. These waves occur in the retina—the inner layer of the eye that senses light and transmits signals to the brain—well ...

Scientists uncover new on-switch for pain signaling pathway that could lead to safer treatment and relief

2025-11-20

Researchers at Tulane University, with a team of colleagues from eight other universities, have discovered a new nerve cell signaling mechanism that could transform our understanding of pain and lead to safer, more effective treatments. The study, co-led by Matthew Dalva, director of the Tulane Brain Institute and professor of cell and molecular biology in the School of Science and Engineering and Ted Price at the University of Texas at Dallas, reveals that neurons can release an enzyme outside the cell that switches on pain signaling after injury. The work, published in Science, offers new insight ...

Modeling of electrostatic and contact interaction between low-velocity lunar dust and spacecraft

2025-11-20

Due to the unique conditions of the space environment and abundant resources, the field investigation and study of the Moon, Earth’s sole natural satellite, represent a crucial milestone in China’s forthcoming deep space endeavors. The successful collection of lunar soil by the Chang’E-5 mission signifies the next phase of the lunar exploration program, which aims to establish a preliminary research station on the lunar south pole. Highly adhesive fine dust particles with an adhesion strength of 0.1 to 1.0 kN/m2, which originate from the regolith, ...

Building a sustainable metals infrastructure: NIST report highlights key strategies

2025-11-20

The National Institute of Standards and Technology (NIST) has published a report identifying strategies for developing a more efficient, sustainable and resilient U.S. metals processing infrastructure, where metals are used and reused more efficiently throughout the economy. The report highlights key challenges that must be addressed to achieve this goal, including a lack of robust standards for recycled content and supply chain vulnerabilities for critical materials. Metals processing covers the entire material life cycle, including mining, alloy design, manufacturing, ...

Giant impactor Theia formed in the inner Solar System

ELSE PRESS RELEASES FROM THIS DATE:

LAST 30 PRESS RELEASES: