Tag Archives: evidence

Researchers Discover Oldest Evidence of Earth’s Magnetic Field in Greenland

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Recovering ancient records of the Earth's magnetic field is difficult because the magnetization of rocks is often reset by heating during burial due to tectonic movements over a long and complex geological history. Geoscientists from MIT and elsewhere have shown that rocks in West Greenland's Isua supercrustal zone have experienced three thermal events throughout their geological history. The first event was the most important, heating rocks to 550 degrees Celsius about 3.7 billion years ago. His two subsequent phenomena did not heat the region's northernmost rocks above 380 degrees Celsius. The authors use multiple lines of evidence to test this claim, including paleomagnetic field tests, metamorphic mineral assemblages across the region, and temperatures at which the radiometric ages of observed mineral assemblages are reset. They use this body of evidence to argue that an ancient record of Earth's magnetic field from 3.7 billion years ago may be preserved in the striated iron layer at the northernmost edge of the magnetic field. .

Earth's magnetic field lines. Image credit: NASA's Goddard Space Flight Center.

In a new study, Professor Claire Nicholls from the University of Oxford and colleagues examined a range of ancient iron-bearing rocks from Isua, Greenland.

Once locked in place during the crystallization process, iron particles effectively act as tiny magnets that can record both the strength and direction of a magnetic field.

Researchers found that 3.7 billion-year-old rocks exhibited magnetic field strengths of at least 15 microteslas, comparable to modern magnetic fields (30 microteslas).

These results provide the oldest estimates of the strength of Earth's magnetic field derived from whole rock samples, providing a more accurate and reliable estimate than previous studies using individual crystals.

“It's very difficult to extract reliable records from rocks this old, so it was really exciting to see the primary magnetic signals start to emerge when we analyzed these samples in the lab,” Professor Nichols said. said.

“This is a very important step forward in our efforts to understand the role of ancient magnetic fields in the creation of life on Earth.”

Although the strength of the magnetic field appears to remain relatively constant, the solar wind is known to have been significantly stronger in the past.

This suggests that surface protection from the solar wind may have strengthened over time, thereby allowing life to leave the protection of the oceans and migrate to the continents.

The Earth's magnetic field is created by the mixing of molten iron within a fluid outer core, driven by buoyancy as the inner core solidifies, forming a dynamo.

During the early stages of Earth's formation, a solid inner core had not yet formed, leaving unanswered questions about how the initial magnetic field was maintained.

These new results suggest that the mechanisms driving Earth's early dynamo were as efficient as the solidification processes that generate Earth's magnetic field today.

Understanding how the strength of Earth's magnetic field has changed over time is also key to determining when Earth's interior solid core began to form.

This helps us understand how fast heat is escaping from the Earth's deep interior, which is key to understanding processes such as plate tectonics.

A key challenge in reconstructing Earth's magnetic field back in time is that any event that heats rocks can change the preserved signal.

Rocks in the Earth's crust often have long and complex geological histories that erase information about previous magnetic fields.

However, the Isua supercrustal zone has a unique geology, sitting on a thick continental crust and protected from extensive tectonic movements and deformation.

This allowed scientists to build clear evidence for the existence of magnetic fields 3.7 billion years ago.

The results may also provide new insights into the role of magnetic fields in shaping the development of Earth's atmosphere as we know it, particularly regarding the release of gases into the atmosphere.

“In the future, we hope to expand our knowledge of Earth's magnetic field before oxygen increased in the Earth's atmosphere about 2.5 billion years ago by examining other ancient rock sequences in Canada, Australia, and South Africa. “We believe that this is the case,” the authors said.

“A better understanding of the strength and variability of ancient Earth's magnetic field will help determine whether the planet's magnetic field was important for harboring life on the planet's surface and its role in the evolution of the atmosphere. Masu.”

of study Published in Geophysical Research Journal.

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Claire IO Nichols other. 2024. Possible Archean record of geomagnetism preserved in the Isua supercrustal zone of southwestern Greenland. Geophysical Research Journal 129 (4): e2023JB027706; doi: 10.1029/2023JB027706

Source: www.sci.news

Pentagon report finds no evidence of US cover-up of UFO existence

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According to a recent Pentagon report, there is no reliable evidence to support the belief that U.S. authorities have hidden extraterrestrial life in the form of unidentified flying objects, despite the strong beliefs of some Americans.

The report provides various explanations for UFO sightings. Over 40% of Americans believe that life forms from another galaxy have visited Earth.

The report, which spans 63 pages and focuses on Unidentified Anomalous Phenomena (UAP), concludes that most sightings are due to misidentification of ordinary objects or phenomena.

Pentagon spokesman Maj. Gen. Patrick S. Rider stated that there is no verifiable evidence to support claims that the U.S. government and private companies are accessing or reverse engineering extraterrestrial technology.

The report lists various satellites and data-gathering vehicles developed by governments or private companies that could be mistaken for UFOs. It also highlights unclassified aircraft from companies like Lockheed Martin and Northrop Grumman as possible sources of false UAP reporting.

Despite the findings of the report, Americans’ beliefs in UFOs are unlikely to change due to the prevalence of misinformation and disinformation, as well as confirmation bias facilitated by modern technology.

The report’s conclusions seem to contradict some elements of a previous House Oversight Subcommittee hearing last July that had firmly established UAP in the public consciousness.

Former US intelligence official David Groush claimed during the hearing that he knew colleagues who had been injured by a drone and had recovered “inhumane biological products” from a downed drone. The Pentagon had previously denied these claims.

Source: www.nbcnews.com

The reasons behind placing trust in people’s words despite conflicting evidence

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Despite the recent surge in “fake news,” misinformation has actually been around for as long as humans have existed. Outlandish claims and conspiracy theories have always been a part of human culture.

Misinformation often originates from, spreads through, and holds significant influence on individuals.

When trying to convey complex information to a general audience, even with strong evidence and expert support, it may still be less convincing than anecdotal evidence like “someone I met in the pub said something different.”

Interestingly, the source of misinformation is often someone close or loosely connected to an individual, rather than a stranger in a pub. This can range from friends to distant acquaintances.

Despite lacking relevant expertise, these individual sources can hold significant influence in shaping beliefs and perceptions.

Humans are not always rational beings, and our brains are heavily influenced by emotions and social connections. Emotional experiences play a significant role in memory retention.

Our brains have evolved to rely on social connections and emotions to gather information. Empathy and emotional connections with others are key factors in how we process information.

Human faces and relationships play a crucial role in how we absorb and understand information. This is evident in the preference for newsreaders over text-only news delivery.

Individuals with personal connections or relatable stories often have a greater impact on us than impersonal sources of information.

Despite the importance of facts, emotions play a significant role in shaping our beliefs and actions. This is why anecdotal evidence from individuals can sometimes carry more weight than concrete research.

Source: www.sciencefocus.com

Webb discovers evidence of hydrothermal activity within Ellis and Makemake

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Methane ice of unknown origin exists on the surfaces of the icy dwarf planets Eris and Makemake. Analysis of data from the NASA/ESA/CSA James Webb Space Telescope shows that Ellis and Makemake have rocky cores that have undergone significant radiation heating and are still hot/hot enough to produce methane. There is a possibility.

grain other. Researchers have discovered evidence of hydrothermal or metamorphic activity deep within the icy dwarf planets Eris and Makemake. Image courtesy of Southwest Research Institute.

“We're seeing some interesting signs of a hot period in a cool place,” said Dr. Christopher Grein, a planetary researcher at the Southwest Research Institute.

“I approached this project thinking that because the cold surfaces of large Kuiper Belt Objects (KBOs) can store volatile materials like methane, they should have ancient surfaces with material inherited from the proto-solar nebula. I participated.”

“Instead, Webb had a surprise for us! We found evidence of a thermal process producing methane from inside Ellis and Makemake.”

Dr. Grein and his colleagues used the Webb to observe isotope molecules on the surfaces of Ellis and Makemake for the first time.

These so-called isotopologues are molecules containing atoms with different numbers of neutrons. These provide data that helps us understand the evolution of planets.

The astronomers measured the composition of the dwarf planet's surface, specifically the ratio of deuterium (deuterium, D) to hydrogen (H) in methane.

Deuterium is thought to have formed in the Big Bang, and hydrogen is the most abundant atomic nucleus in the universe.

The D/H ratio of planetary bodies provides information about the origin, geological history, and formation routes of hydrogen-containing compounds.

“The moderate D/H ratio observed by Mr. Webb discredits the existence of primordial methane on the ancient Earth's surface. The D/H ratio of primordial methane would be much higher,” Dr. Grein said. I did.

“Instead, the D/H ratio indicates the geochemical origin of the methane produced deep inside. The D/H ratio is like a window. You can use it to look into the subsurface.”

“Our data suggest that temperatures in the cores of these world rocks could increase and methane could be cooked.”

“Nitrogen molecule (N2) may be generated as well, and this has also been confirmed in Eris. ”

“Hot cores may also indicate a potential source of liquid water beneath the surface of the ice.”

“If Eris and Makemake harbored, or perhaps still harbor, warm or hot geochemistry in their rocky cores, then the surface of these planets is probably geologically recent, due to cryogenic volcanic activity. could be supplied with methane,” said Dr. Will Grundy. Astronomer at Lowell Observatory.

“We discovered the carbon isotope ratio (13C/12C) suggests that the surface has been resurfaced relatively recently. ”

“Following NASA's New Horizons flyby of the Pluto system, and with this discovery, the Kuiper Belt turns out to be much more alive than we imagined in terms of hosting a dynamic world.” said Dr. Grein.

“It's not too early to start thinking about sending spacecraft to fly close to other of these objects to put Webb's data into geological context. I'm sure we'll see the surprises that lie ahead. I think you’ll be surprised!”

of study It was published in the magazine Icarus.

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Christopher R. Grein other. 2024. Moderate D/H ratios in the Ellis and Makemake methane ices indicate evidence of hydrothermal or metamorphic processes in the interior: a geochemical analysis. Icarus 412: 115999; doi: 10.1016/j.icarus.2024.115999

Source: www.sci.news

New Evidence of Ice-Rich Layered Deposits Found at Medusae Fossai by Mars Express

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Over 15 years ago ESA's Mars Express spacecraft studied the Fossae Formation of Medusae and revealed mysterious deposits up to 2.5 km deep. These early observations left it unclear what the sediment was made of, but a new study provides an answer.

This image shows a height map of the surface of Mars, with the lowest land areas shown in blue and the highest land areas shown in white. Image credit: ESA.

of Formation of medusae fossa (MFF) – a huge and unusual soft rock deposit near Mars' equator – is about one-fifth the size of the continental United States and 100 times the mass of the largest explosive volcanic deposits on Earth.

It consists of several wind-carved features hundreds of kilometers in diameter and several kilometers high.

This feature, discovered at the boundary between highlands and lowlands on Mars, is probably the largest single source of dust on Mars.

Initial observations from ESA's Mars Express spacecraft show that the MFF is relatively transparent to radar and has low density, both characteristics seen in ice deposits.

But planetary scientists couldn't rule out the possibility that the terrain is actually drier, a huge accumulation of windblown dust, volcanic ash, or sediment.

“When we reexamined the MFF using new data from Mars Express's MARSIS radar, we found that the deposits were even thicker than we thought,” said Dr. Thomas Watters, a planetary researcher at the Smithsonian Institution. It's up to 3.7 kilometers thick,” said Dr. Thomas Watters, a planetary researcher at the Smithsonian Institution.

“Interestingly, the radar signal is consistent with what we would expect to see from layered ice, and is similar to the signal seen from the polar caps of Mars, which we know are very ice-rich.”

“If it were to melt, the ice trapped in the MFF would cover the entire planet in a layer of water 1.5 to 2.7 meters deep. This would be the largest amount of water ever discovered in this region of Mars. That's enough to fill Earth's Red Sea.”

“This is where the new radar data comes in. Given its depth, if the MFF is just a huge dust pile, we would expect it to be compressed under its own weight,” says the Italian National Institute of Astrophysics. said researcher Dr. Andrea Cicchetti.

“This will produce something much denser than what we're actually seeing with MARSIS.”

“And when we modeled how different materials behave without ice, nothing reproduced the properties of MFF. We need ice.”

“The new results suggest that there is instead a layer of dust and ice, topped by a protective layer of dry dust or ash hundreds of meters thick.”

In this image, the white line on Mars' surface (top) indicates the stretch of land scanned by Mars Express's MARSIS radar. The graph below shows the topography and subsurface structure of the land, with layers of dry sediment (likely dust or volcanic ash) shown in brown and layers of likely ice-rich sediment shown in blue. I am. The graph shows that the ice deposits are thousands of meters high and hundreds of kilometers wide. Once all the suspected water ice in the MFF melts, Mars will be covered by an ocean of water up to 2.7 meters deep. Image credit: CReSIS / KU / Smithsonian Institution.

“This latest analysis challenges our understanding of the MFF and raises as many questions as it answers,” said ESA Project Scientist for Mars Express and the ESA ExoMars Trace Gas Orbiter. said Dr. Colin Wilson.

“How long ago did these ice deposits form? What was Mars like at that time?”

“If confirmed to be water ice, these giant deposits could change our understanding of Mars' climate history.”

“Any ancient water reservoir would be an attractive target for human or robotic exploration.”

Result is, journal Geophysical Research Letters.

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thomas watters other. 2024. Evidence for ice-rich layered deposits in the Medusa Fossa Formation on Mars. Geophysical Research Lettersin press.

Source: www.sci.news

Ministers urge update of computer evidence laws to prevent another Horizon case

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Legal experts are calling for immediate changes to the law to recognize that the computer was at fault, otherwise risking a repeat of the Horizon incident.

Under English and Welsh law, computers are presumed to be ‘trusted’ unless proven otherwise, leading to criticism that it reverses the burden of proof in criminal cases.

Stephen Mason, a barrister and electronic evidence expert, stated, “If someone says, ‘There’s something wrong with this computer,’ they’re supposed to have to prove it, even if it’s the person accusing them who has the information.”


Mason, along with eight other legal and computer experts, proposed changes to the law in 2020 after the High Court’s ruling against the Post Office. However, their recommendations were never implemented.

The legal presumption of computer reliability comes from the old common law principle that “mechanical instruments” should be presumed to be in good working order unless proven otherwise.

An Act in 1984 ruled that computer evidence was admissible only if it could be shown that the computer was working properly, but this law was repealed in 1999.

The international influence of English common law means that the presumption of reliability is widespread, with examples from New Zealand, Singapore, and the United States supporting this standard.

Noah Weisberg, CEO of legal AI platform Zuva, emphasized the urgency of re-evaluating the law in the context of AI systems and the need to avoid assuming error-free computer programs.

Weisberg also stated, “It would be difficult to say that it would be reliable enough to support a conviction.”

James Christie, a software consultant, suggested two stages of changes to the law, requiring those providing evidence to demonstrate responsible development and maintenance of the system, as well as disclosing records of known bugs.

The Ministry of Justice declined to comment on the matter.

Source: www.theguardian.com

Using scientific evidence to determine if your dog truly loves you

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Scientists who study non-human animals do not use the word “love” in their published papers. Ironically, most animal behavior scientists were initially drawn to this topic due to their profound and enduring interest in animals.

However, researchers have traditionally been trained not to use anthropomorphic terms such as “love” to describe the emotions of non-human animals. Instead, they use terms like “temperament” and “positive cognitive bias” to avoid anthropomorphism. Though this strict stance on using human terminology for non-humans is starting to soften, due in part to the usefulness of certain terms in describing animal behavior and strong evolutionary reasons to believe that non-human animals are not completely dissimilar to humans.

Observing dog behavior makes it clear that dogs are deeply in love with humans, although some may refer to it as “hypersocial” or “socially obsessed.” There are also questions about how to recognize and define “love” in non-human animals who lack the linguistic capabilities to communicate their emotions.

Various studies have examined dogs’ sensitivity to human emotional states and physiological responses, such as separation anxiety and heart rate changes. These studies shed light on the complex relationship between dogs and humans and suggest that dogs may indeed experience emotions similar to love.

Credit: Justin Padgett

On the other hand, some behaviors that appear affectionate may be vestigial or instinctual rather than expressions of genuine affection. For example, wolves, dogs’ closest ancestors, use behaviors such as “kissing” as part of their natural interactions. Physiological research on heart rate, hormones, and brain activity provides further evidence of the bond between dogs and humans.

Researchers have found that both dogs and humans experience a decrease in heart rate after being reunited, indicating a physiological connection. Similarly, the hormone oxytocin, known for its role in human bonding, is also involved in dog-human bonding.

Furthermore, fMRI images of dog brains show activity in the reward center when dogs are near their owners, suggesting a positive emotional response. This evidence, combined with dogs’ ability to form associations and respond to human cues, implies a deep emotional bond between dogs and humans.

Source: www.sciencefocus.com

Bloodstains at crime scene reveal forensic evidence from tail

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Recent research published in fluid physics Scientists at Boston University and the University of Utah have introduced a new aspect of bloodstain analysis. This study focused on the “tail” of the bloodstain, which could provide additional information about the blood droplet’s size, velocity, and impact angle. These discoveries represent a major advance in forensic science, with implications for crime scene reconstruction and verification of eyewitness testimony.

New research in forensic science has revealed that the “tail” of a bloodstain provides important information about the origin of the blood droplet, enhancing crime scene analysis and evidence interpretation.

Forensic science has taken the public imagination by storm, as evidenced by the abundance of “true crime” media over the past decade or so. Evidence such as blood left at a crime scene can now reveal key information for investigating and understanding the circumstances of a crime, and scientific methods can help interpret that information. , now almost everyone knows.

in fluid physicsA group of scientists from Boston University and the University of Utah have demonstrated in AIP Publishing how bloodstains can yield even more valuable details than those typically collected by detectives, forensic scientists, and crime scene investigators. The researchers studied how these “tails” form by examining protrusions that deviate from the boundaries of oval bloodstains.

“These protrusions are typically only used to figure out the direction in which the droplet has moved, and are otherwise ignored,” says author James Byrd.

Within a few milliseconds, tiny droplets of blood impact the solid surface, forming the shape of a stain. Of particular interest is a protrusion that occurs on the right side and deviates from the boundaries of the oval stain.Credit: James C. Byrd

In fact, previous studies have mainly focused on large blood droplets that fall vertically onto flat or inclined surfaces, where gravity can distort the shape of the tail and make it difficult to see. In contrast, the new study involved a series of high-speed experiments in which droplets of human blood, less than a millimeter in diameter, were bombarded with horizontal surfaces at different angles.

“We showed that the precise flow that determines the length of the tail is different from the flow that is responsible for the size and shape of the oval part of the stain,” Bird said. “In other words, the tail length contains additional, independent information that helps analysts reconstruct where the blood drop actually came from.”

Indeed, the tail length may reflect information about the size, impact velocity, and impact angle of the blood droplet that formed the stain. Measuring multiple blood stains within a stain pattern allows the trajectory of the droplet to be traced back to its presumed origin.

Although their analysis only used horizontal planes to examine impact velocity dynamics, Byrd and colleagues hope this will spark further research focusing on the tail length of bloodstain patterns. Masu. They believe that incorporating tail length into standard bloodstain analysis will provide more robust evidence information.

“Knowing the origin of bloodstains at a crime scene can help detectives determine whether the victim was standing or sitting, and corroborate or challenge eyewitness testimony,” Byrd said. said.

Reference: “Bloodstain Tail: Asymmetry helps reconstruct oblique shocks” by Garam Lee, Daniel Attinger, Kenneth F. Martin, Samira Shiri, and James C. Byrd, November 2023 21st of the month fluid physics.
DOI: 10.1063/5.0170124

Source: scitechdaily.com