Metastones Reevaluate the Formation Timeline of Our Solar System

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Northwest Africa 12264 Meteorite Stones Are Older Than Anticipated

Ben Hofnagers

Tiny chips from a singular meteorite may completely challenge our current understanding of the solar system’s formation, as it has proven to be older than initially thought.

Earlier research indicated that small, rocky entities known as protoplanets formed relatively later, scattered across the asteroid belt between Mars and Jupiter. Interestingly, it is believed that the inner regions formed around 4.563 billion years ago, a slightly older timeline compared to the inner protoplanet’s age of 4.566 billion years. This age discrepancy was presumed to be due to the outer regions containing more water and ice, which would have slowed the inner core’s melting process.

This timing gap, while brief in the grand scheme of cosmology, was long accepted as a component of our cosmic history. Now, according to Ben Ryder Stokes from the Open University in Milton Keynes, UK, this notion needs reevaluation.

Planetary formation is typically thought to occur through accretion, where dust and gas are pulled in by gravitational forces, followed by differentiation—where the accumulated material heats up, melts, and separates into cores, mantles, and crusts. This process was previously thought to unfold at slightly divergent times for the early solar system’s internal and external protoplanets, but that view is now under scrutiny.

The team’s pivotal finding centers on a small meteorite named Northwest Africa 12264. Weighing around 50 grams, it was acquired in 2018 from a dealer in Morocco. Researchers obtained consent from the owner to analyze fine particles shaved from the meteorite, revealing that the ratio of chromium to oxygen—which varies in known patterns throughout our solar system—indicated the stones originated from the outer regions.

The meteorite’s composition also indicated that it came from the area between the core and crust, specifically the mantle, marking the first sample found from the outer solar system’s mantle. “This planet must have undergone significant upheaval to expose material from such depths,” states Ryder Stokes. “There surely must have been a colossal impact involved.”

Crucially, however, the age determined through lead isotopes contradicts the prevailing belief that the outer protoplanet should be younger. “This finding is astonishing, as it implies some of the oldest materials in the solar system,” he explains. “It suggests that rocky planets formed simultaneously in both the inner and outer solar system.”

Sebastiaan Krijt from the University of Exeter in the UK notes that shifts in events occurring over millions of years may not seem exigent at the time, yet could have profound implications. Understanding the sequence of events that shaped the solar system and the interactions of the various processes involved is essential for studying both solar systems and star systems throughout the universe.

“These stages of formation are considerably brief, and a mere million years can create significant distinctions,” Krijt remarks. “Getting the chronology and sequence of events correct is of utmost importance.”

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Source: www.newscientist.com

Experts Question Kennedy’s Proposed Timeline for Discovering Autism’s Cause

National Health Secretary Robert F. Kennedy Jr. vowed on Thursday to assemble experts from around the world to investigate the reasons behind the increasing rate of autism in the United States.

“We have initiated an extensive testing and research initiative involving hundreds of scientists globally,” Kennedy declared during a cabinet meeting hosted by President Trump. “By September, we will have identified the causes of the autism epidemic and will be able to eliminate those exposures.”

“This will be a significant press conference,” Trump responded.

However, scientists who have dedicated years to uncovering the cause of autism expressed doubts about Kennedy’s proposed timeline.

They noted the complexities involved in identifying a singular cause in potential contributors like pesticides, air pollution, and maternal diabetes.

Dr. Philip Landrigan, a pediatrician and expert in environmental toxins, cited the current extensive layoffs and reductions in Kennedy’s research at the Department of Health and Human Services as a reason to question such swift progress.

“It is hard to envision a significant scientific breakthrough by September, especially with the current pause of various other pediatric illness research at hospitals and medical schools due to funding cuts from HHS,” Landrigan remarked.

Kennedy’s office did not provide many specifics about the plan initially. Later that day, Kennedy offered more insights, indicating that the National Institutes of Health would lead the initiative.

He mentioned the Centers for Disease Control and Prevention would be central to the effort. I’ll release the data soon, showing an increase in autism diagnoses in one in every 31 children. Many experts believe the rise in autism rates is due to heightened awareness of the spectrum of disorders and expanded diagnostics.

“We are receiving inquiries from scientists nationwide and globally,” Kennedy stated. In an interview with Fox News. “All factors are being considered—from our food system to water, air quality, child-rearing practices, and other changes that may have contributed to this epidemic.”

In an interview, Kennedy also mentioned the intention to compare autism rates between vaccinated and unvaccinated children. Many scientists dismiss this approach, pointing out that parents who vaccinate their children are more likely to seek diagnoses due to increased interactions with healthcare providers.

Numerous researchers and scientists have long worked to find the cause of autism. They have started to identify factors like pesticide exposure, solvents in the workplace, maternal infections during pregnancy, maternal diabetes, and exposure to chemicals like phthalates and PFA, known for their persistent nature in the environment.

Studies have indicated that environmental exposures may interact with human genes in varying ways, underscoring the complexity of autism. Dr. Hertz-Picciotto added that obtaining funding for clinical studies into autism causes is challenging, but new research could propel the field forward, although it may take years.

Describing all the research to be completed by September as “silly,” Dr. Alice Kuo, chief of pediatric medicine for autism at the University of California, Los Angeles, mentioned her involvement in a longstanding NIH project that investigated children’s health nationwide.

The study, which followed thousands of children and parents to uncover potential autism causes, was costly and prematurely terminated, according to Dr. Kuo.

She emphasized that planning and designing a study would take months, and unraveling the answers would require years of research.

In a social media post, Kennedy thanked the president and the Make America Healthy Commission for their support. The commission was established by executive order in February to assess threats to children from various exposures and propose a strategy to address the findings.

Source: www.nytimes.com

Revising the Timeline of Interbreeding Between Neanderthals and Ancient Humans

overview

  • Many people carry small pieces of Neanderthal DNA, evidence of interbreeding between Neanderthals and ancient human ancestors.
  • Two new studies suggest that interbreeding occurred during the limited period when ancient humans left Africa.
  • Clarifying that timeline narrows the range of possible times for humans to spread to new continents.

The genetic code of many people hides mysteries that have long intrigued scientists. It’s a tiny piece of Neanderthal DNA that persists tens of thousands of years after the species disappears.

Most people outside Africa can attribute about 1% to 2% of their DNA to Neanderthal ancestry.

However, the details of its evolutionary history remain unclear. How often did ancient humans and Neanderthals interbreed? When exactly did it happen? Why did Neanderthals become extinct and why did modern humans survive? That Neanderthal DNA What is it bringing us now?

Two research groups independently analyzed collections of ancient genomes and reached the same conclusions about some of their core questions. published research Published in Nature magazine and thursday science Evidence suggests that ancient humans and Neanderthals interbred for a limited period of time as humans left Africa and migrated to new continents.

The results suggest that a wave of interbreeding occurred approximately 43,500 to 50,500 years ago. Then, over the next 100 generations, most, but not all, of the Neanderthal DNA was culled. The remaining DNA is now associated with traits such as skin pigmentation, immune response, and metabolism.

New findings suggest that this interbreeding event occurred more recently than previous estimates suggested, shifting and narrowing the window during which humans may have spread to places like modern-day China and Australia. That’s what it means.

The importance of fossilized human remains dating back more than 50,000 years, discovered in Europe and other parts of the world, has also been revealed. According to a new study, those populations became extinct and reached an evolutionary dead end.

“Human history is not just a success story. In fact, humans went extinct several times,” said Johannes Krause, author of the Nature paper and professor at Germany’s Max Planck Institute for Evolutionary Anthropology. “There are multiple lineages that we’re identifying now that didn’t affect later people.”

The discovery also shows how adept anthropologists are at reconstructing ancient DNA and analyzing it to infer the course of human history.

Priya Muajani, author of the Science paper and assistant professor of molecular and cellular biology at the University of California, said: “We can look at past events and actually reconstruct what the path we are on will be. It’s a great thing to be able to do.” Berkeley. “Although 50,000 years ago is a long time ago, having genetic data available from these samples really helps paint a more detailed picture.

The two research groups took different approaches to the study.

Moorjani’s group cataloged genomic information from 59 ancient and 275 modern humans who lived between 2,000 and 45,000 years ago. The researchers then analyzed how the distribution and length of Neanderthal DNA in those genomes changed over time.

They determined that the influx of Neanderthal genes into humans occurred about 47,000 years ago and lasted less than 7,000 years. These findings are consistent with archaeological evidence suggesting that Neanderthals and humans overlapped geographically when humans left Africa. Many scientists suspect that the two species crossed paths in the Middle East, but this has not been confirmed.

After interbreeding, natural selection retained some Neanderthal traits and discarded many more.

Source: www.nbcnews.com