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Volcanic eruptions may have sparked life on Earth through lightning

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Volcanic lightning, which occurs within the clouds of volcanic ash released during some volcanic eruptions, may be a source of nitrogen.

Mike Rivers/Getty Images

Analysis of volcanic rocks revealed large amounts of nitrogen compounds, almost certainly formed by volcanic lightning. This process may have provided the nitrogen that the first life forms needed to evolve and thrive.

Nitrogen is a key component of the amino acids that are linked to make the proteins on which all life depends. Nitrogen gas is abundant, but plants cannot convert it into usable forms like carbon dioxide.

Instead, plants get most of their nitrogen from bacteria that can “fix” the gas by converting it into nitrogen compounds such as nitrate.But nitrogen-fixing bacteria didn't exist when life first evolved. Suliman Becchi There must have been non-biological sources early on, as it was at the Sorbonne University in Paris.

Lightning from thunderstorms is one possible cause. Currently, this produces relatively small amounts of nitrate, but it may have been important early in Earth's history. The famous Miller-Urey experiment of the 1950s demonstrated that nitrogen compounds containing amino acids could have been produced by lightning in Earth's early atmosphere.

Now Becchi and his colleagues show that another source may be lightning that occurs in ash clouds during volcanic eruptions.

When researchers collected volcanic deposits from Peru, Turkey, and Italy, they were initially surprised to find large amounts of nitrate in some layers. Isotopic analysis of these nitrates showed that they were originally present in the atmosphere and were not emitted by volcanoes. But Becchi says that amount is too much to be produced by lightning during thunderstorms. “It was an amazing amount of money,” he says. “It's really huge.” That means the nitrate was probably produced by volcanic lightning.

“When we looked at the various possibilities, volcanic lightning was the most likely,” Becchi said. “We know that when large-scale volcanic eruptions occur, a lot of lightning occurs.”

Tamsin Mather Researchers at the University of Oxford say their team's conclusions make sense. “Volcanic eruptions like the one studied in the paper would be expected to produce significant lightning, so it's quite possible that volcanic lightning generated this signal,” she says.

Life is thought to have first evolved around volcanoes, and the team's findings indicate that this environment may have been rich in nitrogen compounds, Becchi said.

The idea that volcanic lightning played an important role in the origin of life is not new. Jeffrey Bada Researchers at the Scripps Institution of Oceanography in California have previously shown that volcanic lightning passing through volcanic gases can produce molecules such as amino acids. “This paper just reinforces what I've published,” he says.

Source: www.newscientist.com

Researchers are uncertain about the origins of life on Earth

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If you open your eyes anywhere on Earth, there is life, whether it’s pigeons in the park or invisible microbes covering every surface. However, when the Earth was born 4.5 billion years ago, it was barren. How did the first life originate?

Simply put, I don’t know. Then you’ll be able to reproduce it. Scientists can put the right chemicals into a sealed container under the right conditions, and when they open it, they will find a living organism. No one has ever done this before.

But while we don’t know exactly how life began, there are plenty of clues.

Let’s start with the simplest. What is life made of, and where do its components come from? Living organisms contain thousands of chemicals, including proteins and nucleic acids that carry genetic information. Although these chemicals are complex, we now know that their constituent parts are very easily formed.

The first evidence for this was published in 1953 by a young chemist named Stanley Miller. He filled a glass device with water and his three gases to imitate the oceans and air of the young Earth. Miller heated water and delivered an electric shock to the air to imitate lightning. Within a few days, the setup produced amino acids, which are fragments of proteins.

Since then, scientists have conducted many similar studies. In a study published in September 2020, researchers led by Sara Simcucci, now president of a startup company, Alchemy Co., Ltd.), compiled dozens of experiments. They created a “map” that shows how chemicals change into other substances. He started with just six chemicals used daily, such as water and methane. Creates the tens of thousands of substances found in living things.

The implication is that the young Earth was a biochemical factory. However, having a large amount of these chemicals does not necessarily mean that life will emerge. Just like a pile of bricks automatically becomes a house.

This is where things get tricky. Because we have to think about why something is alive. It boils down to three things. Firstly, the organism often has to maintain itself with an outer layer, and removing that outer layer immediately becomes a problem. Secondly, it must feed itself. This involves complex chemical reactions. And third, life must reproduce itself. In other words, life must have genes that can be inherited.

As we know, life requires proteins. Despite being complex chemicals, they form very easily in nature © Getty Images

Research into the origins of life over the past 50 years has been dominated by attempts to create one of these systems on our own, for example by creating genetic molecules that reproduce by copying themselves. Other bits were supposed to come later.

Personally, I have doubts about this approach. None of the three systems live alone; they need each other. Moreover, if Earth were so good at making all the chemicals for life, all three systems could have formed in the same place at the same time. This may be more likely to occur in confined spaces such as deep-sea hydrothermal vents or terrestrial pools.

We still don’t know exactly how life originated, but what was once a complete mystery is now less inexplicable.

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Source: www.sciencefocus.com

Are You Suffering from Text Neck? The Physical Effects of Phone Usage on Our Bodies | Life and Style

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Earlier this year, a patient came to physical therapist Teresa Marco complaining of neck pain. Marco, who is based in New York City, began the interview as usual, asking a series of questions about lifestyle, habits, and attitude. Soon, a person believed to be the culprit appeared. It was a woman’s cell phone.

Marco, who declined to give her name for privacy reasons, said the woman typically used her phone or tablet with her head down on her lap. “She’s going to be very, very bent over, so it’s going to put a lot of strain on her neck,” Marco said.

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Marco says he often talks to his patients about how to use their phones. “I don’t think people end up coming to physical therapy because they realize they have a problem with their cell phone,” Marco says. But as she solves problems, it often becomes a focus.

While the negative effects on mental health associated with smartphone use are often discussed, the physical effects can also be significant.serious consequences like
Selfie-related injuries and deathscan occur, but chronic problems are much more common, especially in the upper body.
This year is research
Using hospital data, they estimated that between 2011 and 2019, hand and wrist injuries caused by cell phone use nearly doubled, reaching about 7,300 cases per year.

“Like [phone] Carolyn Somerich, director of the Human Factors/Ergonomics/Safety Engineering Laboratory at The Ohio State University, said: These sentiments are not new, but according to a Gallup poll,
Number of people who reported using a smartphone
“Too much” increased from 39% in 2015 to 58% in 2022. He was 84% most likely to feel this way.

Source: www.theguardian.com

The global gender gap in life expectancy is closing.

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Over the past few decades, both men and women have benefited from improvements in medical care.

ZUMA Press, Inc./Alamy

Women have historically lived longer than men, but due to lifestyle changes, men may be gradually catching up.

Worldwide, The average human lifespan has increased Over the past century, this trend is expected to continue as countries become richer.Despite this increase, disparities remain persistent. Between the average lifespan of men and women.

You can learn more about david atance del olmo Researchers from the University of Alcalá in Spain analyzed mortality data from 194 countries from 1990 to 2010. These countries can generally be classified into five groups according to longevity trends.

The group with the highest life expectancy consisted of countries with the highest incomes, including Australia, Japan, the United States, the United Kingdom, and the rest of Western Europe. Rwanda and Uganda were the only groups with the lowest life expectancy.

Comparing the average life expectancy of men and women in these countries, men in Rwanda and Uganda experienced the largest increase in life expectancy, from just 30.85 years in 1990 to 45.22 years, an increase of 14.37 years in 2010. became. Life expectancy for women in these countries increased by just 0.94 years from 50.37 years to 51.31 years during this period.

Among the group with the longest life expectancy, the average life expectancy in 1990 was 4.84 years, favoring women. This decreased slightly to 4.77 years for her in 2010, but researchers predict that the gap will narrow further, reaching 3.4 years for him by 2030.

The researchers observed the same trends for three other groups of countries.

Although the researchers only looked at data through 2010, they expect similar trends to continue into the present. However, they acknowledge that COVID-19 may have had an impact on human life expectancy, particularly for men.

In recent decades, both men and women have benefited from medical advances and increased awareness of diseases such as AIDS, Del Olmo said. Smoking and alcohol-related deaths, which particularly affect men, were also down, which may have contributed to narrowing the gap in life expectancy between men and women, he said.

“This study is consistent with epidemiological trends that suggest global life expectancy is increasing and gender disparities are narrowing over time,” he says. Brandon Yang at the University of California, San Francisco.

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Source: www.newscientist.com

Turning Stress into a Positive Force: Hacking Strategies for a Stress-Free Life

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Many of us have felt some amount of stress over the past few years. Exhibit A for me is my teeth. A recent trip to the dentist confirmed that I had been clenching my jaw for months due to the pandemic. This was the result of the normal stress of deadlines, compounded by the demands of two young children, four of whom had broken bones.

A broken tooth is a small fry. Last year, the American Psychological Association Two-thirds of people in the US report feeling more stressed due to the pandemic, found, and predicted “a mental health crisis that could have serious health and social consequences for years to come.” Increased risks of diabetes, depression, and cardiovascular disease are all associated with high stress levels. Just thinking about it makes me feel stressed.

But maybe we just need to think about stress differently. At least, that's the surprising conclusion of researchers studying the mind-body relationship. They say there are natural benefits to feeling stressed, and if we change the way we “think about stress,” we can turn things around and make stress have a positive impact on our lives. maybe. Fortunately, there are some simple hacks that can help you do this, and you can expect to see improved physical health, clarity of thought, increased mental strength, and increased productivity. Masu.

There's no denying that too much stress can have a negative impact on your body and mind. In the West, it has been linked to all six major causes of death: cancer, heart disease, liver disease, accidents, lung disease, and suicide. Your immune system may be weakened, making you more susceptible to infections and less infectious.

Source: www.newscientist.com

New Method Discovered by Astronomers for Detecting Water Oceans and Alien Life on Rocky Exoplanets

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Planets that are too close to their star (such as Venus) are too hot, and planets that are too far away (such as Mars) are too cold, but planets that are within the habitable zone have just the right temperature. Although great efforts have been made to identify planets in the theoretical habitable region of stars, until now there has been no way to know whether a planet really has liquid water. Now, astronomers from the University of Birmingham and the Massachusetts Institute of Technology have found that if an exoplanet’s atmosphere has less carbon dioxide than its neighbors, it may have liquid water on its surface. It was shown that it was suggested.

Artist’s impression of the super-Earth planet Ross 508b. Image credit: Sci.News.

Astronomers have detected more than 5,200 extrasolar worlds so far. Modern telescopes allow us to directly measure the distance from a planet to a star and the time it takes to complete one revolution.

These measurements help scientists infer whether a planet is within its habitable zone.

However, there was no way to directly confirm whether a planet was truly habitable, i.e. whether there was liquid water on its surface.

Throughout our solar system, astronomers can detect the presence of liquid oceans by observing glints, flashes of sunlight reflecting off liquid surfaces.

These glows, or specular reflections, have been observed, for example, on Saturn’s largest moon, Titan, and helped identify the moon’s large lakes.

However, detecting similar glows on distant planets is not possible with current technology.

But astronomer Julien de Witt of the Massachusetts Institute of Technology, astronomer Amaury Tryaud of the University of Birmingham and colleagues believe there is another habitable landform close to home that could be detected far away. I noticed something.

“Looking at what was happening to terrestrial planets in our own star system gave us an idea,” Tryaud said.

Venus, Earth, and Mars share similarities in that all three are rocky and live in relatively temperate regions relative to the Sun.

Earth is the only planet of the three that currently has liquid water. Researchers then noted another clear difference. That means there is significantly less carbon dioxide in Earth’s atmosphere.

“We think these planets formed in a similar way, and if we find a planet with less carbon than it does now, it must have gone somewhere else,” Tryaud said.

“The only process that can remove this much carbon from the atmosphere is a strong water cycle involving oceans of liquid water.”

In fact, Earth’s oceans have played a major and persistent role in absorbing carbon dioxide.

For hundreds of millions of years, the ocean has absorbed enormous amounts of carbon dioxide. This is about the same amount that remains in Venus’ atmosphere today.

This planetary effect has resulted in Earth’s atmosphere being significantly depleted in carbon dioxide compared to neighboring planets.

Dr. Frieder Klein, a researcher at the Woods Hole Oceanographic Institution, said: “On Earth, much of the carbon dioxide in the atmosphere is sequestered in seawater and solid rock over geological timescales; It has helped regulate climate and habitability for billions of years.” .

Astronomers reasoned that if a similar decrease in carbon dioxide was detected on a distant planet compared to a nearby planet, this would be a reliable signal of a liquid ocean and life on its surface. did.

“After an extensive review of the literature in many fields, from biology to chemistry to carbon sequestration related to climate change, we found that if carbon depletion is indeed detected, it is likely that liquid water and its effects are “We think this is likely a strong indication that this is a sign of life.” Dr. de Witt said.

In the study, the researchers developed a strategy to detect habitable planets by looking for traces of depleted carbon dioxide.

Such searches are ideal for “pea” systems, like our solar system, in which multiple terrestrial planets, all about the same size, orbit relatively close to each other.

The first step, the scientists suggest, is to confirm that a planet has an atmosphere by simply looking for the presence of carbon dioxide, which is expected to dominate the atmospheres of most planets.

“Carbon dioxide is a very strong absorber of infrared light and can be easily detected in the atmospheres of exoplanets,” Dr. de Witt said.

“The carbon dioxide signal could reveal the presence of an exoplanet’s atmosphere.”

Once astronomers determine that multiple planets in a system have atmospheres, they move on to measuring their carbon dioxide content to see if one planet has significantly less than the others.

If so, this planet is likely habitable, which means there is a large amount of liquid water on its surface.

However, habitable conditions do not necessarily mean that the planet is inhabited. To confirm whether life actually exists, the authors suggest that astronomers look for another feature in the planet’s atmosphere: ozone.

On Earth, plants and some microorganisms contribute to absorbing carbon dioxide, although to a lesser extent than the oceans. Nevertheless, as part of this process, living organisms release oxygen, which reacts with solar photons and turns into ozone. Ozone is a much easier molecule to detect than oxygen itself.

If a planet’s atmosphere shows signs of both ozone and carbon dioxide depletion, the planet may be habitable and inhabited by humans.

“If you see ozone, there’s a pretty good chance it’s related to carbon dioxide being consumed by life forms,” ​​says Tryaud.

“And if it’s life, it’s glorious life. It won’t be just a few bacteria. It’ll be a planetary-scale biomass that can process and interact with large amounts of carbon.”

The researchers believe NASA/ESA/CSA’s James Webb Space Telescope can measure carbon dioxide, and possibly ozone, in nearby multiplanetary systems like TRAPPIST-1, a seven-planet system orbiting a bright star. I’m guessing it is. Light years from Earth.

“TRAPPIST-1 is one of the few systems that can use the Web to study Earth’s atmosphere,” said Dr. de Witt.

“We now have a roadmap to finding habitable planets. If we all work together, we may make paradigm-changing discoveries within the next few years.”

of study It was published in the magazine natural astronomy.

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AHMJ triode other. Atmospheric carbon depletion as a tracer of water oceans and biomass in temperate terrestrial exoplanets. Nat Astron, published online on December 28, 2023. doi: 10.1038/s41550-023-02157-9

Source: www.sci.news

Former Apple Employee Shares iPhone Hacks to Extend Battery Life

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The average American checks their cell phone Average 96 times per dayor once every 10 minutes.

To better cope with such heavy usage, a former Apple employee shared the best battery-saving hacks to help users see and scroll through TikTok texts throughout the day.

Tyler Morgan, who previously worked in sales at Apple and recently received 11.1 million views, has revealed the best tips and tricks to preserve battery power. Check him out @hitomidocameraroll or watch the video on TikTok.

First, Morgan warned users not to charge their iPhones to 100% or overnight. Instead, he recommended only allowing the battery to reach 80% to prevent chemical degradation once it reaches a full charge. Users can go to “Settings, Battery, Battery Health and Charging, [charging optimization]” to set a limit of 80%.

Tyler Morgan, who previously worked as a sales representative at Apple, recently racked up 11.1 million views after revealing his best tips and tricks for preserving battery power for as long as possible. Prima91 – Stock.adobe.com

Morgan also recommended turning off background activity by going to Settings, General, and clicking Background App Refresh. He explains that all the apps running in the background use battery power to keep them updated, so users can switch to updating only on Wi-Fi or when opened.

He warned that users should not charge their iPhones to 100% or overnight. tiktok.com/@hitomidocameraroll

Morgan suggested iPhone users turn off the “Hey, Siri” feature in Siri and Search for those who don’t rely on their personal assistant. He also recommended going to “Accessibility”, “Motion” and clicking “Reduce Motion” to save battery life.

Morgan then advised users to turn off automatic updates and reduce brightness and Bluetooth usage. He acknowledged that it might make the phone experience worse but could be useful in saving battery. He also showed viewers how to use iPhone features more efficiently, such as opening the video feature directly from the camera app and using the one-handed keyboard option.

Morgan advised users to turn off certain features such as automatic updates, background activity, and location services. tiktok.com/@hitomidocameraroll

This helpful hack comes after users experienced rapid battery drain and expressed privacy concerns following the iOS 17 upgrade. The latest software improvements, iPhone Operating System 17.2, include bug fixes related to virtual car keys and financial features, addressing these security concerns.

Source: nypost.com

AI trained on extensive life stories has the ability to forecast the likelihood of early mortality

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Data covering Denmark’s entire population was used to train an AI that predicts people’s life outcomes

Francis Joseph Dean/Dean Photography/Alamy Stock Photo

Artificial intelligence trained on personal data covering Denmark’s entire population can predict people’s likelihood of dying more accurately than existing models used in the insurance industry. Researchers behind the technology say it has the potential to have a positive impact on early prediction of social and health problems, but must be kept out of the hands of large corporations. There is.

Sune Lehmann Jorgensen The researchers used a rich Danish dataset covering the education, doctor and hospital visits, resulting diagnoses, income, and occupation of 6 million people from 2008 to 2020.

They converted this dataset into words that can be used to train large-scale language models, the same technology that powers AI apps like ChatGPT. These models work by looking at a set of words and statistically determining which word is most likely to come next based on a large number of examples. In a similar way, the researcher’s Life2vec model can look at the sequence of life events that form an individual’s history and determine what is most likely to happen next.

In the experiment, Life2vec was trained on all data except for the last four years of data, which was kept for testing. Researchers took data on a group of people aged 35 to 65, half of whom died between 2016 and 2020, and asked Life2vec to predict who lived and who died. This was 11% more accurate than existing AI models and life actuarial tables used in the financial industry to price life insurance policies.

The model was also able to predict personality test results for a portion of the population more accurately than AI models trained specifically to do the job.

Jorgensen believes the model has consumed enough data that it has a good chance of shedding light on a wide range of topics in health and society. This means it can be used to predict and detect health problems early, or by governments to reduce inequalities. But he stresses that it can also be used by companies in harmful ways.

“Obviously, our model should not be used by insurance companies, because the whole idea of ​​insurance is that if some unlucky person suffers some kind of incident, dies, loses their backpack, etc. ‘Because we share the lack of knowledge about what to do, we can share this burden to some extent,’ says Jorgensen.

But such technology already exists, he says. “Big tech companies that have large amounts of data about us are likely already using this information against us, and they are using it to make predictions about us. It is.”

Matthew Edwards Researchers from UK professional institutes the Institute of Actuaries and the Faculty of Actuaries say that while insurers are certainly interested in new forecasting techniques, the bulk of decision-making is based on a type of model called a generalized linear model. The research is done using AI, which he says is rudimentary compared to this research. .

“If you look at what insurance companies have been doing for years, decades, centuries, they’ve taken the data they have and tried to predict life expectancy from that,” Edwards said. “But we are deliberately conservative in adopting new methodologies, because when we are creating policies that are likely to be in place for the next 20 or 30 years, the last thing we want is to make any significant mistakes. . Everything can change, but slowly because no one wants to make mistakes.”

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Source: www.newscientist.com

Potential presence of cyanide in the ocean of Saturn’s moon Enceladus could aid in sustaining life

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Illustration of NASA’s Cassini spacecraft diving through the plume of Saturn’s moon Enceladus.

NASA/JPL-California Institute of Technology

The plumes of water vapor spewing from Enceladus’ surface appear to contain hydrogen cyanide, which, perhaps counterintuitively, suggests that there may be life in the oceans beneath the surface of this icy moon of Saturn. It shows that it is possible.

The Cassini spacecraft flew through Enceladus’ plume several times in the early 2000s, capturing samples as it hurtled past. Preliminary analyzes of these samples have revealed several elements and compounds that may be important for life, but many are not, as the molecules tend to fracture after impacting Cassini’s sampling chamber at high speeds. It has been difficult to identify specific compounds.

Jonah Peter Researchers at Harvard University performed a reanalysis of the Cassini data using new statistical methods and were able to extract more compounds present in the plume. They found evidence of several previously undetected compounds, including hydrogen cyanide, acetylene, ethane, and even trace amounts of the alcohol methanol.

All of these compounds could be part of chemical reactions important to life, but hydrogen cyanide is particularly promising.

“We still don’t have a complete picture of the molecules that are there and are necessary for the origin of life. We don’t even know how the origin of life occurred on Earth,” Peter said. say. “But we know a lot about some of the building blocks that are necessary for the beginning of life, and hydrogen cyanide is one of those very versatile building blocks.”

We know that it can be a building block for amino acids, RNA, and other large biomolecules, so its presence in the plume points to the possibility of life in Enceladus’ subsurface ocean. That’s a good sign.

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Source: www.newscientist.com

Start-up founders allege that investors undermined their company with false user accusations in real life

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IRL founders Abraham Shafi and Genrik Khachatryan are suing investors for intentionally sabotaging the company.

At its peak, IRL was poised to become an alternative way to host events for Gen Z, who were using Facebook less and less.

CEO Shafi said: Paused It was ordered by IRL in April to investigate allegations of misconduct. In June, IRL’s board of directors discovered after an investigation that 95% of the company’s 20 million users were fake. The founders now claim investors accounted for the 95% figure “as an excuse to shut down the company and return capital to shareholders.”

The lawsuit specifically names Goodwater Capital’s Chihua Qian, SoftBank’s Selina Dale, and Floodgate’s Mike Maples. From these investors his social calendar app raised more than $200 million and the valuation brought him $1.17 billion. Notably, SoftBank led IRL’s $170 million Series C round in 2021. Mr. Shafi and Mr. Khachatryan accused the investors of wanting to shut down the company because they were “trying to finance a large portion of the company’s $40 million in cash reserves.”

Although IRL is defunct, the remaining board members deny the founders’ claims.

“Immediately after the Shafi outage, IRL experienced a significant drop in the number of daily active users virtually overnight. This was not due to an outage,” IRL and its board said in a statement, and an IRL spokesperson said: Elliott Sloan shared with TechCrunch. The same report that found 95% of users are fake also cited “the existence of private groups with millions of duplicate names, irregular signatures from Hotmail, Yahoo email addresses, and burner email addresses. The statement said they also discovered “suspicious user behavior such as Said. Forensic reports show that his IP address from proxy-his servers was used extensively, with individual accounts cycling through his IP address and device type, which could be linked to user behavior. indicates that it is invalid.

“Based on this, and evidence of Shafi’s misappropriation of company funds and repeated obstruction of investigations, the board, after several months of consideration, has concluded that the company’s future prospects are unsustainable.” The statement concludes.

As of December of last year, the SEC. ongoing investigation IRL may have misled investors and violated securities laws.

IRL is just one once-hot start-up that has come under fire for potentially tampered metrics. Investors say Bolt and co-founder Ryan Breslow of the giant one-click checkout company misrepresented the company’s financials as it sought to raise $355 million in a Series E round. raised concerns and faced SEC investigation. But 15 months later, the SEC said the company likely not to be prosecuted. And earlier this year, the SEC charged student financial aid startup Frank with defrauding JPMorgan, which acquired the company for $175 million in 2021. JPMorgan has filed a lawsuit accusing Frank’s founder Charlie Jarvis of defrauding millions of customers to get her bank to buy her. company.

IRL lawsuit by tech crunch On Scribd

Source: techcrunch.com

The Process of a ‘Bouncing’ Comet Spreading Life Across the Galaxy

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Researchers at the University of Cambridge have discovered how comets can deliver the molecular building blocks of life to planets in our galaxy, particularly those in the “pea-in-a-pod” system, where the planets orbit each other closely. It was demonstrated that

Cambridge researchers have proposed that comets could carry the building blocks of life to other planets, especially in the “pea-in-a-pod” system. Their findings suggest that these molecules can survive on planets with close orbiting neighbors, providing new insights into the search for extraterrestrial life.

How did the molecules that make up life originate on Earth? One long-standing theory is that they may have been transported by comets. Now, researchers from the University of Cambridge have shown how comets can deposit similar building blocks on other planets in the galaxy.

The role of Comet Speed ​​and the “Peas in a Pod” system

To transport organic material, comets must travel relatively slowly, at speeds of less than 15 kilometers per second. At higher speeds, critical molecules cannot survive. The speed and temperature of the impact causes the molecules to break apart.

The most likely place for a comet to travel at a reasonable speed is in a “pea in a pod” system, where groups of planets orbit closely together. In such systems, comets can essentially pass or “bounce” from one planet’s orbit to another, slowing them down.

If the velocity is slow enough, the comet will hit the planet’s surface, releasing intact molecules that researchers believe are precursors to life. The results were announced on November 15th. Proceedings of the Royal Society A suggests that if the arrival of comets is important for the origin of life, such systems would be promising places to look for life outside the solar system.

Comet: carrier of prebiotic molecules

Comets are known to contain various building blocks of life known as prebiotic molecules. For example, a sample of asteroid Ryugu analyzed in 2022 showed that the asteroid was delivered intact. amino acid and vitamin B3. Comets also contain large amounts of hydrogen cyanide (HCN), another important prebiotic molecule. HCN has strong carbon-nitrogen bonds, making it highly resistant to high temperatures. This means that it can survive and remain intact even if it enters the atmosphere.

Lead author Richard Anslow, from the Cambridge Institute of Astronomy, said: “We’re constantly learning more about the atmospheres of exoplanets, so we’re wondering whether there are planets out there where complex molecules could be transported by comets. I wanted to find out.” “It’s possible that the molecules that brought life to Earth came from comets, and the same could be true for other planets in our galaxy.”

The researchers do not claim that comets are necessary for the origin of life on Earth or other planets, but instead place limits on the types of planets to which complex molecules such as HCN can be successfully transported by comets. I was thinking about it.

Comet path and influence on the solar system

Most of the comets in our solar system are located outside of Earth’s orbit. Neptune,So-called kuiper belt. When comets and other Kuiper Belt Objects (KBOs) collide, they can be pushed toward the Sun by Neptune’s gravity and eventually pulled into the Sun. Jupitergravity. Some of these comets pass through the asteroid belt and enter the inner solar system.

“Earth is currently the only example of a planet with life, so we wanted to test our theory on a planet similar to ours,” Anslow said. “What kind of comet, moving at what speed, could deliver intact prebiotic molecules?”

Using various mathematical modeling techniques, the researchers determined that it is possible for comets to carry precursor molecules throughout their lives, but only in certain scenarios. For a planet to orbit a star similar to our Sun, the planet must have a low mass, and it is beneficial for the planet to be in a close orbit to other planets in the system. The researchers found that nearby planets in close orbits are much more important for planets around low-mass stars, whose typical velocities are much higher.

In such a system, a comet could be pulled in by the gravity of one planet and pass by another before colliding with it. If this “comet pass” occurs enough times, the comet’s velocity will be slow enough that some prebiotic molecules will be able to survive atmospheric entry.

“In these dense systems, each planet has a chance to interact with and capture the comet,” Anslow said. “This mechanism could be how prebiotic molecules reach the planet.”

For planets orbiting low-mass stars like M dwarfs, complex molecules are more difficult to transport by comets, especially if the planet’s density is loose. Rocky planets in these systems are also exposed to higher velocity collisions, which can pose unique challenges for life on these planets.

Implications for the search for extraterrestrial life

Researchers say their results could help determine where to look for life outside the solar system.

“It’s interesting that we can start to identify the types of systems that can be used to test different origin scenarios,” Anslow said. “This is another way of looking at the great work already being done on Earth. What molecular pathways gave rise to the wide variety of life we ​​see around us? Are there other planets with similar pathways? These are exciting times, as we can combine advances in astronomy and chemistry to study some of the most fundamental questions.”

Reference: “Can comets deliver prebiotic molecules to rocky exoplanets?” RJ Anslow, A. Bonsor, PB Rimmer, November 15, 2023. Proceedings of the Royal Society A Mathematical Physics and Engineering Sciences.

DOI: 10.1098/rspa.2023.0434

This research was supported by the Royal Society and part of the Science and Technology Facilities Council (STFC), which is part of UK Research and Innovation (UKRI). Richard Anslow is a Fellow of Wolfson College, Cambridge.

Source: scitechdaily.com