New research shows that the structure formed when an asteroid or comet struck the region roughly 43 to 46 million years ago.

The investigation was led by Dr. Uisdean Nicholson of Heriot-Watt University in Edinburgh and supported by the Natural Environment Research Council (NERC). The team combined seismic imaging, microscopic analysis of rock fragments, and computer modeling to produce the clearest evidence yet that Silverpit is one of Earth’s rare impact craters.

The study appears in the journal Nature Communications.

A Hidden Crater Beneath the North Sea

Silverpit lies about 700 meters beneath the seabed in the North Sea, roughly 80 miles off the coast of Yorkshire.

Since geologists first identified the formation in 2002, the three kilometer wide crater and its surrounding ring of circular faults spanning about 20 km have sparked intense debate.

Early research proposed that the feature was created by a high speed asteroid impact. Supporters of that idea pointed to its round shape, central peak, and surrounding concentric faults, which are often seen in known impact craters.

Other scientists suggested different explanations. Some proposed that underground salt movement distorted the rock layers and created the structure. Others argued that volcanic activity may have caused the seabed to collapse.

In 2009, geologists even voted on the issue. According to a report in the December 2009 issue of Geoscientist magazine, most participants rejected the asteroid impact explanation at the time.

The latest findings now overturn that conclusion.

New Seismic Data Reveals Evidence of Impact

Nicholson’s team analyzed newly available seismic imaging and geological samples taken from beneath the seabed.

Dr. Uisdean Nicholson, a sedimentologist in Heriot-Watt University’s School of Energy, Geoscience, Infrastructure and Society, said: “New seismic imaging has given us an unprecedented look at the crater.

“Samples from an oil well in the area also revealed rare ‘shocked’ quartz and feldspar crystals at the same depth as the crater floor.

“We were exceptionally lucky to find these — a real ‘needle-in-a-haystack’ effort. These prove the impact crater hypothesis beyond doubt, because they have a fabric that can only be created by extreme shock pressures.”

These microscopic minerals form only under the extreme pressures generated during asteroid impacts, providing strong confirmation of the event.

Asteroid Strike Triggered a Massive Tsunami

The evidence indicates that an asteroid about 160 meters wide slammed into the seabed at a shallow angle from the west.

Dr. Nicholson said: “Our evidence shows that a 160-meter-wide asteroid hit the seabed at a low angle from the west.

“Within minutes, it created a 1.5-kilometer high curtain of rock and water that then collapsed into the sea, creating a tsunami over 100 meters high.”

The impact would have produced a violent explosion at the seafloor and sent enormous waves spreading across the region.

The “Silver Bullet” That Ended the Debate

Professor Gareth Collins of Imperial College London attended the 2009 debate about the crater’s origin and contributed the numerical simulations used in the new research.

Professor Collins said: “I always thought that the impact hypothesis was the simplest explanation and most consistent with the observations.

“It is very rewarding to have finally found the silver bullet. We can now get on with the exciting job of using the amazing new data to learn more about how impacts shape planets below the surface, which is really hard to do on other planets.”

A Rare and Well Preserved Impact Crater

Dr. Nicholson said, “Silverpit is a rare and exceptionally preserved hypervelocity impact crater.

“These are rare because the Earth is such a dynamic planet — plate tectonics and erosion destroy almost all traces of most of these events.

“Around 200 confirmed impact craters exist on land, and only about 33 have been identified beneath the ocean.

“We can use these findings to understand how asteroid impacts shaped our planet throughout history, as well as predict what could happen should we have an asteroid collision in future.”

Confirming Silverpit as an impact crater places it in the same category as well known structures such as the Chicxulub Crater in Mexico, which is linked to the dinosaur mass extinction, and the Nadir Crater off the coast of West Africa that was recently identified as another impact site.

The research was funded by the Natural Environment Research Council (NERC).

Their findings, published in the peer reviewed journal Nature, describe a nearly complete skeleton of Alnashetri cerropoliciensis. This dinosaur belonged to a peculiar group of bird like theropods called alvarezsaurs. These animals are known for their tiny teeth and unusually short arms that end in a single enlarged thumb claw.

For decades, scientists struggled to understand this group because most well preserved fossils had been discovered in Asia. Fossils from South America were often incomplete, leaving major gaps in the evolutionary story.

Patagonia Discovery Provides a Crucial Specimen

The almost complete Alnashetri fossil was uncovered in 2014 in northern Patagonia, Argentina, at a fossil rich site famous for exceptionally preserved Cretaceous animals. The species had originally been named several years earlier based on fragmentary remains, but the new skeleton provided a far clearer view of the animal’s unusual body structure.

Preparing the specimen was a slow and careful process. Over the past decade, researchers meticulously cleaned and assembled the delicate bones to prevent damage to the small and fragile skeleton.

“Going from fragmentary skeletons that are hard to interpret, to having a near complete and articulated animal is like finding a paleontological Rosetta Stone,” said Peter Makovicky, lead author of the study and a professor in the University of Minnesota Department of Earth and Environmental Sciences. “We now have a reference point that allows us to accurately identify more scrappy finds and map out evolutionary transitions in anatomy and body size.”

The fossil is providing scientists with valuable insight into how this lineage of dinosaurs evolved, became smaller, and spread across ancient continents.

Insights Into the Evolution of Tiny Dinosaurs

The skeleton reveals that Alnashetri differed from its later relatives in several ways. It had longer arms and larger teeth, showing that some alvarezsaurs had already evolved very small body sizes before developing the specialized features that later species used for what scientists believe was an “ant-eating” diet.

Microscopic examination of the bones also showed that the animal was fully grown and at least four years old. These dinosaurs rank among the smallest known non avian dinosaurs, and they remained small throughout their lives. Even the largest members of the group only reached about the size of an average human, which is tiny compared with most dinosaurs. Alnashetri itself weighed less than 2 lbs, making it one of the smallest dinosaurs discovered in South America.

By studying additional alvarezsaur fossils preserved in museum collections across North America and Europe, the team also found evidence that these animals appeared much earlier than scientists previously believed. Their widespread distribution likely occurred when the continents were still connected as the supercontinent Pangaea. The later breakup of Earth’s landmasses explains how the animals became scattered across the globe rather than migrating across oceans.

Fossil Site Continues To Reveal Ancient Life

The well preserved skeleton came from the La Buitrera fossil area, a location that has produced many scientifically important discoveries. Previous finds from the site include early snakes and small saber toothed mammals.

“After more than 20 years of work, the La Buitrera fossil area has given us a unique insight into small dinosaurs and other vertebrates like no other site in South America,” said Apesteguía, a researcher at Universidad Maimónides in Buenos Aires, Argentina.

Scientists are still actively studying fossils from the same region, and more discoveries may soon add to the story of these unusual dinosaurs.

“We have already found the next chapter of the alvarezsaurid story there, and it is in the lab being prepared right now,” added Makovicky.

International Research Team and Support

The research involved an international collaboration of scientists. In addition to Makovicky and Apesteguía, the team included Jonathan S. Mitchell from Coe College in Iowa; Jorge G. Meso and Ignacio Cerda from Instituto de Investigación, Universidad Nacional de Río Negro and Museo Provincial; and Federico A. Gianechini from Instituto Multidisciplinario de Investigaciones Biológicas de San Luis.

Funding for the research was provided by the National Scientific and Technical Research Council (CONICET), The Field Museum, National Geographic, University of Minnesota, United States National Science Foundation and the Fulbright U.S. Scholar program.

Each mineral has its own crystal structure and physical properties. Familiar examples include gypsum and hematite. Scientists analyze data from orbiting spacecraft to identify minerals on the Martian surface and reconstruct the environmental conditions that produced them. For nearly two decades, researchers have been puzzled by layered iron sulfates on Mars that show unusual spectral signals. A new investigation led by Dr. Janice Bishop, senior research scientist at the SETI Institute and NASA’s Ames Research Center in California’s Silicon Valley, has now identified and characterized an uncommon ferric hydroxysulfate phase. The team combined laboratory experiments with orbital observations of Mars to better understand these materials. Their results provide new clues about the roles of heat, water, and chemical reactions in shaping the Martian landscape.

“We investigated two sulfate-bearing sites near the vast Valles Marineris canyon system that included mysterious spectral bands seen from orbital data, as well as layered sulfates and intriguing geology,” said Bishop.

Study Sites Near Valles Marineris

The research focused on two areas close to Valles Marineris, one of the largest canyon systems in the solar system. One location is Aram Chaos, situated northeast of the canyon system where ancient water once flowed toward lower terrain to the north. The second site lies on the plateau above Juventae Chasma, a 5-km-deep canyon located just north of Valles Marineris.

Juventae Plateau (above Juventae Chasma)

This region near the cliffs of Valles Marineris preserves signs of a wetter past. Ancient channels carved by flowing water cross the landscape. Scientists found sulfate minerals concentrated in a small low area that likely formed when pools of sulfate-rich water gradually evaporated. As the water disappeared, hydrated ferrous sulfates were left behind.

These minerals, including ferric hydroxysulfate, occur in thin layers roughly a meter thick that sit both above and below basaltic materials. Their position suggests they were later exposed to heat from lava or volcanic ash after they originally formed.

“Investigation of the morphologies and stratigraphies of these four compositional units allowed us to determine the age and formation relationships among the different units,” said Dr. Catherine Weitz, a co-author on the study and Senior Scientist at the Planetary Science Institute.

Evidence From Aram Chaos

Sulfate minerals are widespread throughout the Valles Marineris region, especially in rugged landscapes called chaotic terrains. Scientists believe these areas formed when massive floods reshaped the surface long ago. As the water evaporated, it left layered deposits of iron and magnesium sulfates that provide evidence of a much wetter Mars in the past.

In one chaos terrain that formed within an ancient impact crater, the uppermost layers contain polyhydrated sulfates. Beneath them lie layers of monohydrated sulfates and ferric hydroxysulfate.

How Heat Transformed Martian Sulfates

Each of these sulfate types has a unique spectral signature that can be detected from orbit using the CRISM instrument. At first, the arrangement of these mineral layers was difficult to explain. Laboratory experiments helped solve the puzzle. Researchers found that heating polyhydrated sulfates to 50°C converts them into monohydrated forms. When temperatures exceed 100°C, ferric hydroxysulfate forms. These results indicate that geothermal heat likely altered the minerals after they were deposited.

Polyhydrated and monohydrated sulfates appear across large areas of the region. Ferric hydroxysulfate is much rarer and occurs only in a few small locations. Scientists suspect that warmer geothermal sources once existed beneath these areas, producing the conditions needed to create this mineral. Additional deposits could remain buried under layers of monohydrated sulfates.

Laboratory Experiments Reveal Mineral Transformations

Researchers at the SETI Institute and NASA Ames performed laboratory experiments to trace how these minerals evolve. The process begins with rozenite (Fe²⁺SO₄·4H₂O), which contains four water molecules in each unit cell. Heating transforms it into szomolnokite (Fe²⁺SO₄·H₂O), which contains only one water molecule. Continued heating produces ferric hydroxysulfate, where OH replaces H2O in the mineral structure.

“Our experiments suggest that this ferric hydroxysulfate only forms when hydrated ferrous sulfates are heated in the presence of oxygen,” said postdoctoral researcher Dr. Johannes Meusburger at NASA Ames. “While the changes in the atomic structure are very small, this reaction drastically alters the way these minerals absorb infrared light, which allowed identification of this new mineral on Mars using CRISM.”

Oxygen and Chemical Reactions on Mars

This chemical reaction requires oxygen gas and generates water (Equation 1). Mars currently has a thin atmosphere dominated by CO₂, yet it still contains enough oxygen for this reaction to occur and for other forms of iron to oxidize as well.

Equation 1: 4 Fe²⁺SO₄·H₂O + O₂ → 4 Fe³⁺SO₄OH + 2H₂O

“The material formed in these lab experiments is likely a new mineral due to its unique crystal structure and thermal stability,” said Bishop. “However, scientists must also find it on Earth to officially recognize it as a new mineral.”

Clues to Mars’ Geological Activity

The newly identified ferric hydroxysulfate has a crystal structure similar to szomolnokite, a monohydrated ferrous sulfate. However, it appears to form more readily from rozenite, which contains four water molecules.

The transformation from hydrated ferrous sulfates to ferric hydroxysulfate occurs only when temperatures exceed 100°C, far hotter than typical Martian surface conditions. The sulfates observed at Aram Chaos and Juventae, including ferric hydroxysulfate, probably formed more recently than the surrounding terrain. Researchers suggest they may date to the Amazonian period (<3 billion years ago).

The findings indicate that volcanic heat at the Juventae Plateau and geothermal energy beneath Aram Chaos could convert common hydrated sulfates into ferric hydroxysulfate. This discovery suggests that parts of Mars have remained chemically and thermally active more recently than previously believed, offering new insights into the planet’s evolving surface and its possible ability to support life.

The paper, Characterization of Ferric Hydroxysulfate on Mars and Implications of the Geochemical Environment Supporting its Formation, is published in Nature Communications.

The vacuum of spacetime contains something fundamental. It is difficult to describe precisely with everyday language, but physicists refer to these underlying ingredients as quantum fields. In quantum field theory, the particles that make up our world such as electrons, top quarks, neutrinos, and even dark matter are not independent objects in the usual sense. What we call a particle is actually a visible expression of something deeper.

These deeper structures are the fields themselves. Every type of particle has a corresponding field. These fields permeate every cubic centimeter of space and time. They have existed since the big bang and extend throughout the entire universe.

When we observe a particle, such as an electron moving through space, we are really detecting a ripple or vibration in its underlying field. The particle is a traveling excitation of that field. Even if all particles were removed, the fields would still remain.

Vacuum Energy and the Origin of Dark Energy

These fields also contain energy. Because of the Heisenberg uncertainty principal, the vacuum cannot be completely devoid of energy. When physicists attempt to calculate how much energy exists in empty space, the results can range from extremely large values to theoretically infinite ones…which is also another episode.

What matters is that this vacuum energy produces a measurable effect. That effect is known as “dark energy,” the name scientists use to describe the accelerated expansion of the universe.

Observations show that the actual amount of vacuum energy is relatively small, though it is not zero. In most environments across the universe, its influence is negligible. Regions filled with matter completely dominate the local behavior of space.

Here on Earth, for example, matter is so dense that dark energy has no noticeable impact. If dark energy suddenly vanished, everyday physics would remain unchanged. The path of a thrown baseball would be identical. Your burrito would still cook in the microwave at exactly the same rate. Nothing about daily life would be different.

Where Dark Energy Dominates the Universe

The same situation applies across much of the cosmos. Galaxies, galaxy clusters, filaments, and walls of the cosmic web are all regions packed with matter. In these environments, dark energy plays almost no role.

Cosmic voids are different.

Voids are enormous regions where matter is largely absent. In these areas, the vacuum of space-time itself becomes the dominant influence. If you could place yourself in the middle of a cosmic void, you would effectively be surrounded by dark energy.

In fact, voids are where dark energy carries out its most important work. The accelerated expansion of the universe does not occur inside dense regions such as galaxies or clusters. Instead, it takes place within the vast empty voids.

Cosmic Voids Are Expanding

Cosmic voids are not just empty gaps between structures in the universe. They are actively growing. As dark energy pushes space outward, the voids expand and press against the surrounding cosmic web.

Over immense spans of time, this process gradually pulls the universe’s large-scale structure apart. The intricate network of galaxies, clusters, and filaments that astronomers see today will not last forever. Over the next 5-10-20 billion years the exact number doesn’t matter the cosmic web will slowly fade as expanding voids stretch everything farther apart.

Why Empty Space Is Never Truly Empty

In that sense, cosmic voids are far from empty. They are filled with the subtle energy of quantum fields. That energy influences the entire universe by driving its accelerating expansion.

Voids are the only regions where this effect becomes dominant, precisely because they contain almost nothing else.

So yes, cosmic voids are empty of matter. That is how astronomers identify and measure them. But their lack of matter means they are filled with dark energy.

Wherever you travel in the universe, whether to a nearby galaxy or to the deepest interior of the emptiest void, you will never truly be alone.

During the past decade, global temperatures have climbed at an estimated rate of about 0.35°C per decade, depending on the dataset analyzed. From 1970 through 2015, the average increase was just under 0.2°C per decade. The more recent trend represents the fastest warming observed in any decade since instrumental temperature records began in 1880.

“We can now demonstrate a strong and statistically significant acceleration of global warming since around 2015,” says Grant Foster, a US statistics expert and co-author of the study, which was published today in the scientific journal Geophysical Research Letters.

“We filter out known natural influences in the observational data, so that the ‘noise’ is reduced, making the underlying long-term warming signal more clearly visible,” Foster added.

Removing Natural Climate Variability From Temperature Data

Short term natural events can temporarily raise or lower global temperatures and make it harder to detect changes in long term climate trends. These influences include El Niño events, volcanic eruptions, and variations in solar activity.

To address this challenge, the researchers analyzed measurement data from five widely used global temperature datasets (NASA, NOAA, HadCRUT, Berkeley Earth, ERA5). By adjusting the data to account for these natural factors, the team was able to isolate the underlying warming trend more clearly.

“The adjusted data show an acceleration of global warming since 2015 with a statistical certainty of over 98 percent, consistent across all data sets examined and independent of the analysis method chosen,” explains Stefan Rahmstorf, PIK researcher and lead author of the study.

Statistical Analysis Reveals a Shift in Warming Trends

The study focused on determining whether the pace of warming has changed, rather than identifying the causes behind that shift.

After accounting for the influence of El Niño and the recent solar maximum, the extremely warm years of 2023 and 2024 appear slightly cooler in the adjusted analysis. Even with these corrections, they still rank as the two warmest years recorded since instrumental measurements began. Across all datasets, the faster warming trend becomes visible around 2013 or 2014.

To evaluate whether the warming rate has changed since the 1970s, the researchers applied two statistical techniques: a quadratic trend analysis and a piecewise linear model that identifies when shifts in warming rates occur.

Implications for the Paris Agreement Climate Target

The study does not attempt to determine the specific reasons behind the acceleration in warming. However, the authors note that climate models already allow for the possibility that the rate of warming could increase over time.

“If the warming rate of the past 10 years continues, it would lead to a long-term exceedance of the 1.5°C limit of the Paris Agreement before 2030,” says Stefan Rahmstorf. “How quickly the Earth continues to warm ultimately depends on how rapidly we reduce global CO₂ emissions from fossil fuels to zero.”

The study shows that different cell types, tissues, and cancers each display their own distinctive arrangement of metabolic enzymes within the nucleus. These enzymes interact with DNA in patterns that researchers describe as a “nuclear metabolic fingerprint,” marking the first evidence that human cells may carry such unique nuclear signatures.

Scientists still need to determine the precise role these enzymes play in the nucleus. They could be driving chemical reactions, influencing whether genes are switched on or off, or contributing to structural support. Even so, the findings already provide new insights into how tumors develop, adapt, and sometimes resist therapy.

“Many of these enzymes synthesize essential building blocks of life, and their nuclear localization is associated with DNA repair. Their presence in the nucleus may therefore directly shape how cancer cells respond to genotoxic stress, a hallmark of many chemotherapeutic treatments. It’s an entirely new world to explore,” says Dr. Sara Sdelci, corresponding author of the study and researcher at the Centre for Genomic Regulation.

Studying Proteins Bound to Chromatin

To identify these enzymes, the research team used a technique that isolates proteins physically attached to chromatin, the natural packaging of DNA in human cells. Using this approach, they examined 44 cancer cell lines and 10 healthy cell types collected from ten different tissues.

Metabolism and genome regulation have traditionally been viewed as largely separate biological systems. The nucleus houses the genome, while metabolic enzymes normally produce energy in mitochondria and the cytoplasm.

Because of this assumption, the scale of the discovery surprised the researchers. They found that metabolic enzymes appear to play active roles in nuclear biology. About 7 percent of all proteins attached to chromatin turned out to be metabolic enzymes. This observation suggests that the nucleus may operate its own small metabolic network described by the researchers as a ‘mini metabolism’.

Unexpected Energy Pathways Inside the Nucleus

Some of the enzymes detected were particularly surprising. The team identified proteins involved in oxidative phosphorylation, the cellular process responsible for generating most of a cell’s energy, as regular occupants of the nucleus.

The pattern of these enzymes also varied depending on cancer type. Oxidative phosphorylation enzymes were commonly observed in breast cancer cells but were largely missing in lung cancer cells. When scientists examined tumor samples taken directly from patients, they observed the same trend, confirming that nuclear metabolism varies depending on tissue type and disease.

“We’ve been treating metabolism and genome regulation as two separate universes, but our work suggests they’re talking to each other, and cancer cells might be exploiting these conversations to survive,” says Dr. Savvas Kourtis, first author of the study.

Enzymes Move to Damaged DNA

The researchers also performed experiments to understand what these nuclear enzymes actually do. They focused on a group of enzymes responsible for producing molecules needed for DNA synthesis and repair.

Their experiments showed that these enzymes gather near chromatin when DNA damage occurs. By concentrating in these regions, they appear to assist with repairing the genome.

The team also discovered that the function of an enzyme can depend on its location inside the cell. One enzyme, called IMPDH2, behaved differently depending on where it was located. When researchers forced it to remain inside the nucleus, it helped maintain genome stability. When the same enzyme was restricted to the cytoplasm, it influenced entirely different cellular pathways.

Implications for Cancer Treatment

These findings raise important questions about how cancer treatments work. Some therapies target metabolic processes in cancer cells, while others focus on disrupting DNA repair systems. If these two biological processes are more tightly connected than previously thought, it could change how scientists approach cancer treatment.

“It could help explain why tumors of different origins, even when carrying the same mutations, often respond very differently to chemotherapy, radiotherapy, or targeted inhibitors,” says Dr. Sdelci.

Mapping Nuclear Metabolism

According to the researchers, this study provides the first large scale evidence that metabolic enzymes are widely present inside the nucleus. Over time, mapping where these enzymes are located and understanding their functions could help identify biomarkers for diagnosing cancer or reveal new weaknesses that anti cancer drugs could target.

However, researchers emphasize that much work remains. Scientists still need to determine whether all of the enzymes observed in the nucleus are active and what specific roles each one plays.

“Each enzyme may have its own, unique nuclear function, so this must be addressed one by one,” says Dr. Kourtis.

How Large Enzymes Enter the Nucleus

Another unanswered question involves how these enzymes reach the nucleus in the first place. The nucleus is separated from the cytoplasm by a barrier that normally limits which molecules can pass through nuclear pores.

Many of the enzymes discovered on DNA are significantly larger than the size these pores are believed to allow. Despite this, the bulky proteins still manage to enter the nucleus.

This puzzling observation suggests that cells may use an as yet unknown mechanism to move large enzymes into the nucleus. Understanding how this process works could eventually reveal precise therapeutic targets for controlling nuclear metabolic activity in diseased cells.