De eerste complexe levensvorm op aarde verscheen mogelijk veel eerder dan verwacht: de studie

door Janine

Abderrazzak El Albani/ Université de Poitiers

Een nieuwe studie heeft de opvattingen over de ontwikkeling van de eerste vormen van complex leven omvergeworpen: dit was veel eerder dan werd gedacht.

Het verschijnen van de eerste vormen van leven op aarde

Wat wordt bedoeld met complexe levensvormen? Onder deze wezens zijn er ook wezens die we tot nu toe als de eenvoudigste beschouwen. Deze laatste zijn in feite heel ingewikkeld en ondanks enorme ontwikkelingen op wetenschappelijk gebied is het nog steeds onmogelijk om ze helemaal opnieuw in het laboratorium te creëren. We hebben het over de allereerste levensvormen waarvan tot nu toe werd aangenomen dat ze lang na de vorming van de planeet zelf op aarde verschenen.

In werkelijkheid lijkt dit helemaal niet het geval te zijn: de eerste levende wezens zagen het licht toen onze aardbol zich nog in een vroeg stadium bevond, 300 miljoen jaar na zijn ontstaan 4,5 miljard jaar geleden. Dit betekent dat de aarde in zo'n korte tijd omstandigheden heeft ontwikkeld die haar gastvrij maakten voor leven. Hoewel er in de allereerste dagen van haar ontstaan geen omstandigheden op onze planeet waren die geschikt waren voor de ontwikkeling van leven, dan veranderde dat in geologische termen relatief snel.

Complexe levensvormen: ze kunnen dateren van 2,1 miljard jaar geleden

Abderrazzak El Albani

Dankzij de studie van het genoom van moderne organismen weten we nu dat de eerste vorm van leven op aarde 4,2 miljard jaar geleden ontstond. Het gaat om LUCA, Last Universal Common Ancestor, de voorouder die alle levende wezens op aarde gemeen hebben.

Nu heeft nieuw onderzoek uitgewezen dat de eerste complexe levensvormen mogelijk 1,5 miljard eerder in onze oceanen zijn ontstaan ​​dan eerder werd aangenomen. Wetenschappers dachten namelijk dat de vroegste dierlijke levensvormen dateerden van 635 miljoen jaar geleden en evolueerden tot wezens met zachte lichamen in het tijdperk Ediacarium, naar schatting tussen 635 en 541 miljoen jaar geleden, als gevolg van het stijgende fosforgehalte in de zeeën. De nog niet gepubliceerde studie suggereert echter dat de vroegste vorm van complex leven veel ouder is en rond 2,1 miljard jaar geleden in het tijdscontinuüm ligt: de auteurs van de ontdekking, waaronder wetenschappers van de Cardiff University in het Verenigd Koninkrijk, vermoeden de aanwezigheid van primordiale gefossiliseerde levensvormen in sedimentafzettingen in Franceville, Gabon, Centraal-Afrika.

Geïsoleerd oceaanreservaat: was het de thuisbasis van complex leven?

Volgens het team zouden deze archaïsche levensvormen zijn uitgestorven voordat ze zich in de rest van de wereld vermenigvuldigden en ontwikkelden. De afzettingen zijn ongeveer 2,5 km dik en daarin zouden deze mysterieuze, oeroude gefossiliseerde wezens verborgen liggen. De auteurs onderzochten deze primordiale rotsformaties op tekenen van mogelijk leven in het verleden, waaronder fosfor en zuurstof: de resultaten toonden aan dat een plotselinge en grote golf geladen met fosfor een geïsoleerd deel van de oceaanbodem bereikte, waardoor een omgeving ontstond die geschikt was voor het ontstaan van primitieve levensvormen.

De concentratie van fosfor en zuurstof in de rotsen van dit oceanische reservaat zou volgens wetenschappers veroorzaakt zijn door de botsing tussen continentale platen onder water en door de activiteit van vulkanen. Dit kan een soort zee in de zee hebben gegenereerd die ondiep is en rijk aan voedingsstoffen die nuttig zijn voor de vorming van complex leven, zoals “koloniale macrofossielen”. De isolatie van de rest van de oceaan heeft echter de toegang tot verdere voedingsstoffen verhinderd, waardoor de ontwikkeling van deze levende wezens en hun mondiale verspreiding worden geblokkeerd.

{ https://www.curioctopus.nl/ }

03-08-2024 om 21:20 geschreven door peter  

With the help of advanced capabilities that include the use of undersea robots, scientists are now assembling a clearer picture than ever before of the dynamics of melt occurring at the ice base of West Antarctica’s Dotson Ice Shelf.

Visualization of the sand dune shaped ice structures found on the underside of the Dotson Ice Shelf. 

(Image credit: Filip Stedt / University of Gothenburg)

Basal Melt Processes and Ice Shelf Stability

Melt rates beneath Antarctic ice shelves often show remarkable variability. One factor that influences this process, one that scientists have focused on in recent years, is how warmer salt water interacts with the ice along the base of the continent’s ice sheets.

One significant mechanism that contributes to this mixing of warm water into the ice-ocean boundary is turbulence resulting from shear-driven mixing. Another is vertical convection, which includes a process known as double-diffusive convection, although these generally produce lower melt rates. However, when combined, these processes have now been revealed to produce uniquely shaped features on the base of the ice, which include the formation of what are sometimes very large basal channels and terraces.

Due to varying oceanic conditions, ice can sometimes melt at different rates even along the same ice shelf. This appears to be caused by factors that include not only ocean temperature but also the speed of ocean water’s movement, both of which contribute to diverse formations of natural features along the base of Antarctica’s ice.

According to new findings detailed in a study published in Science Advances, researchers have successfully mapped these changes with the help of an autonomous underwater vehicle (AUV), revealing remarkable and never-before-seen details about the processes that are driving accelerated melt along the continent’s ice shelves.

Structures mapped by an undersea robot named Ran on the underside of the Dotson Ice Shelf in Antarctica. The streaks, etched by currents, are up to 60 feet deep and miles long.

Credit...Filip Sted/University of Gothenburg

Overall, the research team found that the basal topography of the Dotson Ice Shelf varies significantly between its eastern and western portions. While the ice is thicker and appears to be melting more slowly to the east, on the opposite end, the opposite is the case, with noticeably thinner ice indicating higher melt rates.

In their study, the research team links these variances in ice melt rates to the presence of what is called modified Circumpolar Deep Water (mCDW), which refers to Pacific and Indian Ocean water mixing with other nearby water masses and interacting with the ice base. Faster-moving currents in the western region revealed smooth features on the base of the ice, accompanied by higher melt rates.

In contrast, the central and eastern regions of the ice sheet bore evidence of terraced features, which the research team attributes to warm water intrusions that occur closer to these areas.

Ultimately, the presence of remnant winter water and mCDW mixtures was revealed to produce streaks of temperature and meltwater that significantly influence overall melt rates. The team’s findings through AUV observations help to reveal how future missions may be able to reveal further details about the Antarctic ice base and how shear-driven turbulence and the presence of warm water accelerate melting in the western outflow region.

“This new wealth of processes, all active under a single ice shelf, must be considered to accurately predict future Antarctic ice shelf melt,” the team writes in their recent study. Going forward, ongoing mapping and study of the ice shelf will be crucial in order to refine existing models, in addition to improving our understanding of ice-ocean interactions and their relationship to rising sea levels in the years ahead.

The team’s new study, “Swirls and scoops: Ice base melt revealed by multibeam imagery of an Antarctic ice shelf,” by Anna Wahlin, et al., appeared in Science Advances on July 31, 2024.

A visualization of an area in the east, where the water eroded several layers of ice. The structures are carved 20 meters deep into the ice, and they are several kilometers long.CreditCredit...

Filip Stedt/University of Gothenburg

A top level view, taken by the researchers from a helicopter survey, of a crack along the front of the Dotson Ice Shelf.

Credit...Clare Eayrs/Korea Polar Research Institute

• Micah Hanks is the Editor-in-Chief and Co-Founder of The Debrief. He can be reached by email at micah@thedebrief.org. Follow his work at micahhanks.com and on X: @MicahHanks.

{ https://thedebrief.org/category/science/ }

02-08-2024 om 22:55 geschreven door peter  

The Day After Tomorrow? A climate disaster could occur at ANY time in the next 6,000 years, scientists warn

• Researchers say it's almost impossible to predict timing of climate tipping points
• They warn catastrophe could strike at any time in the next 6,000 years

By Xantha Leatham Deputy Science Editor

It's the film that left us all wary of disastrous and abrupt climate change.

But The Day After Tomorrow is probably not when we're going to experience apocalyptic weather events, according to a study.

Researchers argue that it's almost impossible to predict the timing of climate tipping points – and that catastrophe could strike at any time in the next 6,000 years.

A team from the Technical University of Munich and the Potsdam Institute for Climate Impact Research provided the Atlantic Meridional Overturning Circulation (AMOC) as an example.

This system circulates water from north to south and back in a long cycle within the Atlantic Ocean, carrying warm water from the tropics northwards.

It's the film that left us all wary of disastrous and abrupt climate change. But The Day After Tomorrow is probably not when we're going to experience apocalyptic weather events, according to a study 

Read More

• The real-life Day After Tomorrow? The Gulf Stream is weakening thanks to climate change 

Climate models suggest the AMOC will weaken over the 21st century due to increases in greenhouse gases and melting ice.

If the system collapsed the Northern Hemisphere would get colder, causing temperatures in Europe to drop dramatically.

Wet seasons in the Amazon rainforest would be reversed to dry seasons, and in coastal cities the sea would rise even faster.

Previous predictions from historical data suggest a collapse could occur between 2025 and 2095.

However, the new study revealed that uncertainties are so large that these predictions are not reliable.

Using different data sets and analysis, tipping times for the AMOC ranged from 2050 to 8065 – a 6,000-year window which isn't particularly useful, the researchers said.

Writing in the journal Science Advances they said the timing of other climate tipping points – such as the melting of the polar ice sheets or the collapse of tropical rainforests – are also too uncertain.

This is because there is too much still unknown about the underlying physical mechanisms of climate change, a lack of direct observations of the climate system, and incomplete history data, they explained.

Lead author Maya Ben-Yami said: 'Our research is both a wake-up call and a cautionary tale.

Climate models suggest the AMOC will weaken over the 21st century due to increases in greenhouse gases and melting ice. If the system collapsed the Northern Hemisphere would get colder, causing temperatures in Europe to drop dramatically 

'There are things we still can't predict, and we need to invest in better data and a more in-depth understanding of the systems in question.

'The stakes are too high to rely on shaky predictions.'

While the study shows we cannot reliably predict tipping events, the possibility of such events cannot be ruled out either, the team said.

They also stressed that statistical methods are still very good at telling us which parts of the climate have become more unstable.

'We still need to do everything we can to reduce our impact on the climate, first and foremost by cutting greenhouse gas emissions,' co-author Niklas Boers said.

'Even if we can't predict tipping times, the probability for key Earth system components to tip still increases with every tenth of a degree of warming.'

{ https://www.dailymail.co.uk/ }

02-08-2024 om 22:30 geschreven door peter  

Where Did Life Come From, Exactly? The Answer Is Out There

The latest research shows lightning, meteors, and far-off nebulae all played a role in assembling the ingredients for life on early Earth.

BY KIONA SMITH

 

Abdulaziz Alghmdi / 500px/500px/Getty Images

RIDE THE LIGHTNING

Nitrogen is an essential ingredient for life — an element that is found in proteins, amino acids, and DNA. But not just any nitrogen will do. Most of the time, nitrogen atoms are locked together in close-knit pairs, held together by very strong chemical bonds, which means neither atom is available for chemical reactions. So it needs a little jolt to shake it loose.

Harvard University chemist Hahui Jiang and her colleagues’ recent experiments showed that lightning, especially if it struck wet soil near rivers or lakes, can break these bonds, splitting the coupled-up nitrogen into free atoms. That, in turn, could have set the stage for chemical reactions that produced more complex molecules — including important ingredients for living cells and the nutrients they crave.

Jiang and her colleagues published their work in the Proceedings of the National Academy of Sciences, but Sasselov tells Inverse that it’s only one piece of a much larger puzzle. Exactly where the chemical building blocks of life came from is a puzzle that chemists, astronomers, and biologists are still trying to solve. The answer could help explain our own origins, but it also could help us figure out how likely it is that we’re not alone in the universe.

A 1952 experiment by scientists Harold Urey and Stanley Miller found that lightning can jumpstart chemical reactions that, eventually lead to organic chemistry: the types of molecules that eventually become the building blocks of life. But the story of how a planet full of inert chemicals turned into a planet teeming with life, is a lot more complicated than Urey and Miller ever imagined.

“The origin of life question is more of a puzzle, consisting of multiple pieces that need to fit together, rather than a single breakthrough,” Harvard University astronomer Dimitar Sasselov, a coauthor of the recent study, tells Inverse.

IT’S ALIVE!

Some of the chemical ingredients for life form around deep-sea vents where water and rock meet, and where intense heat provides the energy for chemical reactions. Others can be found in erupting volcanoes. More of the chemistry of life probably happens anytime ultraviolet light hits water, according to another recent study. And most astrobiologists also assume comets and meteors delivered some of the ingredients for life to early Earth.

But some of the stuff cells are made of — including some of the most complex chemical compounds on the ingredients list — may have been part of the starter pack for our newly-formed Solar System 4.6 billion years ago. Astronomers have spotted the telltale spectrum of light emitted by an animo acid called tryptophan in a nearby cloud of interstellar gas and dust, and a chemical called ethanolamine, which is a key part of cell membranes, formed in a cold, dark interstellar cloud more than 100,000 light years away. Other organic chemistry — like the ring-shaped molecule benzene, on which most other organic chemistry is based — has been spotted forming in the cloud of gas and dust around a pair of newborn stars, in chemical reactions powered by shock waves.

The reality is that the chemicals that made up the earliest life on Earth may have take a little from column A and a little from column B — a mixture of deep space feedstock and home-grown biochemistry.

“We cannot limit ourselves to think that the answer to the origin of life comes from a single source,” Arhaus University astronomer Sergio Ioppolo, one of the researchers whose team discovered ethanolamine in deep space last year, tells Inverse. “We should also consider that lightning-induced electrochemistry alone cannot explain the onset of life on the early Earth. It is likely that our planet got the building blocks of life by multiple endogenic [local] as well as exogenic [from space] routes.”

RAW MATERIALS ABOUND

Sasselov says that even if the Solar System formed with a starting supply of building blocks — amino acids, ethanolamine, and more — those building blocks couldn’t just assemble themselves into working cells. Instead, according to Sasselov, those complex molecules probably got provided things like phosphorus and carbon to the early Earth.

But even a starting supply of several tons of, say, amino acids, delivered by meteors or baked into Earths’ crust, wouldn’t be enough to sustain organic chemistry long enough for life to emerge. Whatever amino acids and benzene rings found their way to early Earth from deep space, they were more useful for their raw materials than as preassembled components for cells. That’s because the chemistry that led to life needed a constant supply of things like carbon, phosphorus, sulfur, and nitrogren.

“[Those molecules] themselves cannot be directly incorporated into the cells which produce life,” says Sasselov, adding, “We now know that some of those chemical reactions which happen in interstellar space are very different from the ones which can sustainably occur on the surface of the Earth later on.”

So the ethanolamine in your cell membranes probably didn’t form on the surface of a distant bit of interstellar dust, but the ingredients were likely there — being carried through the universe to do their thing on the petri dish that is Earth.

PUTTING IT ALL TOGETHER

“The work of Jiang and her colleagues is one of the many pieces of the puzzle which we should build on,” says Ioppolo.

And the particular piece of the puzzle Jiang and her colleagues were interested in was small but vital: how early Earth got enough nitrogen, in a usable form, to fuel the chemical machinery that eventually produced — and sustained — life. They found that lightning was the solution to that particular piece of the puzzle, especially when it struck water or wet soil, where a wider selection of minerals could get in on the resulting chemical reactions. (In contrast, Urey and Miller just studied the effects of lightning in midair back in 1952, because that’s easier to simulate in a lab.)

Sasselov emphasizes that we shouldn’t picture a single lightning strike spawning life here on Earth. It took a very long time, and a lot of small events adding up, before life finally arose.

“The origin of life is not a single event, or a number of single events, in which the chemistry happened once, almost miraculously, somewhere on the surface of the planet, and then everything went on afterwards,” says Sasselov. “That kind of scenario doesn't work.”

Because the story of life’s origins is so complex, it takes scientists from a wide range of disciplines to put the whole puzzle together.

“In my view, our only chance to address the fundamental question of the origin of life is to put different scientific communities together and tackle the issue from many different perspectives including astronomy, astrochemistry, astrobiology, planetary science, volcanology, and biology,” says Ioppolo.

{ https://www.inverse.com/ }

01-08-2024 om 22:27 geschreven door peter  

An Underwater Drone Helped Scientists Explore the Final Glacial Frontier

Peeking beneath ice shelves is key for predicting sea level rise.

BY LAUREN LEFFER

 

Anna Wåhlin

Ice shelves are often hundreds of meters thick. Through satellite data and radar measurements of the surface, glaciologists can make inferences and estimates about shifts in sea ice behavior unfolding under climate change. Yet a new perspective can offer a whole lot more information, as demonstrated in a study published July 31 in the journal Science Advances. A team of scientists deployed an autonomous underwater vehicle (AUV) to explore beneath Dotson ice shelf, on the western side of Antarctica.

The unmanned submarine traveled more than 600 miles over 27 days, collecting ocean temperature, salinity, and current data while also scanning the bottom of the ice shelf using sonar for the first time. The resulting, detailed measurements allowed the researchers to construct the most detailed maps of the Dotson ever, revealing exactly how the shelf is changing and even new types of ice-shelf formations never seen before.

“It's a bit like seeing the back of the moon,” said Anna Wåhlin, lead study author and a professor of oceanography at the University of Gothenburg in Sweden, in a press statement.

The Dotson shelf is an outflow of the West Antarctic Ice Sheet, the continent’s largest contributor to sea level rise (and second only worldwide to the Greenland Ice Sheet, when it comes to melt volume). Though ice shelves don’t directly contribute to sea level rise, as they’re already floating, ice shelf losses contribute to ice loss on land, as glacial flow moves outward and the shelves and sheets fail to recover under ever-warmer conditions. Shrinking marine ice shelves can destabilize sheets on land.

As climate change progresses, Antarctica is set to become an even larger factor in globally rising tides. Understanding ice sheets is key to improving our predictions of how that melt is likely to unfold, and its subsequent impacts. And the new work offers a deeper understanding of Dotson than scientists have ever had before. The observations could help inform not only how glaciologists assess this one ice shelf but every Antarctic ice shelf.

Past estimates of ice loss have failed to meet reality. This new information, combined with a wave of other recent analyses, will hopefully make for clearer, more accurate forecasts. “These new observations will help the community of ice modelers to reduce the large uncertainties in future sea level,” said Karen Heywood, a study co-author and professor of oceanography at the University of East Anglia in England in the news release.

This is not the first study to use an unmanned submarine to make measurements beneath an ice shelf; the method has been deployed for a few years. However, these are the first sub-shelf AUV data on Dotson, and it’s one of relatively few expeditions to have occurred in a growing field. For now, every mission below an Antarctic ice shelf is notable, and brings new information. Many of the new observations confirmed estimates from surface analyses: Researchers had inferred that the western portion of Dotson is thinning faster than the eastern and central sections. Data collected on currents also bolsters previous hypotheses about why that is. Water is flowing faster beneath the western part of the shelf. Yet some of the observations were totally novel.

Per the AUV scans, the underside of the eastern and central regions of the Dotson Ice Shelf is characterized by large, flat terrace-like topography, bordered by steep walls. The researchers note this melt pattern is likely the result of periodic intrusions of sea water below the ice shelf’s grounding line. In contrast, the western side of the shelf is mostly smooth on the bottom with shallow, odd features like swirling, teardrop-shaped imprints.

“There were cracks and swirls in the ice that we weren’t expecting. It looked more like art,” said Heywood. Initially, the scientists had no idea what was causing these patterns, but they’ve homed in on one hypothesis related to a known ocean current phenomenon called the Ekman spiral.

Yet still, there’s much more to uncover in the massive trove of data compiled by the solo sub. These initial maps are just the tip of the proverbial iceberg. Unfortunately, to make future observations, the researchers will need a new AUV. The marine drone the expedition had been using, dubbed Ran, disappeared below the ice during another expedition, cut woefully short. The observations on Dotson are a final transmission from a lost ship.

{ https://www.inverse.com/ }

01-08-2024 om 22:20 geschreven door peter  

SR-91 Aurora: A Highly Classified American Aircraft

For decades, the US military has pursued the dream of dominating the skies with hypersonic platforms, a dream that China and Russia are also striving to become a reality. In this scenario of fierce competition, a disturbing question arises: is it possible that a Mach 5 aircraft, the mythical SR-91 Aurora, already existed and that its existence has been hidden from us?

The classified SR-91 Aurora project

Whispers about the Aurora, a supposedly classified hypersonic aircraft, have resonated in aviation circles since the 1980s. Yet evidence of this enigmatic triangular craft is as elusive as the wind. Is it conceivable that the United States not only managed to develop and operate a fleet of these aircraft at Mach 5+ during the 1980s but also kept this achievement in the shadows to this day? The truth could be more labyrinthine than we imagine.

The Pentagon, known for its “black programs,” has secretly funded the development of advanced technologies throughout history. Today, the most clandestine efforts are grouped under Special Access Programs, or SAPs, which restrict information to even those with the highest security clearances. Some of these recognized SAPs are never fully revealed, and others remain eternally anonymous.

After examining historical reports, declassified documents, testimonies and discussion forums, it is extremely unlikely that the United States has ever secretly operated a fleet of hypersonic aircraft. However, this does not rule out that such technological marvels have once touched the imposing doors of the hangars of Area 51.

Technology cost-benefit analysis for the SR-91 Aurora

It is vital to remember that there is a vast difference between technology that is mature and reliable enough for mass production and combat operation and that which, although within reach, is not sustainable from economic, resource or even political perspectives.

For example, the iPhone in your pocket is not necessarily the most advanced smartphone in the world; It is simply technology that can be mass-produced for a specific price and consumer. The latest communications technology would probably be much more expensive, potentially less reliable, and capable of leaving you in awe.

Aeronautical programs are advancing in a similar way: an extraordinary plane can be built for $2 billion, but that does not mean that mass production can begin immediately. Technology demonstrations, prototypes and limited production of exotic aircraft are a reality at facilities such as the Lockheed Martin plant in Palmdale or Area 51.

SR-91 Aurora: A response to the need to see without being seen

Sometimes, these efforts do not produce the expected results, are too costly, or require excessive maintenance. And sometimes, America‘s deepest secrets are buried in the desert, condemned to oblivion.

The SR-91 Aurora, if it ever existed, was conceived in response to a strategic need for aerial reconnaissance, a testament to the relentless quest for technological supremacy in a world where secrets and shadows play a crucial role.

Lockheed‘s SR-71 Blackbird, an unrivaled aerial beast and aviation’s fastest gem, laughed in the faces of more than 4,000 missiles with its dazzling speed during its golden era as a sky spy. This colossus, capable of challenging Mach 3 as if it were child’s play, made the most sophisticated surface-to-air missiles and elite fighters useless. So, when the Air Force decided to retire this very expensive technological marvel in the late 1980s, the world could only speculate: the United States must have something even more impressive in its arsenal.

It was not for less. The secret corridors of the Pentagon and Congress whispered about an heir to the Blackbird throne. But now, decades later, fact and fiction have become intertwined in a labyrinth of classified theories and programs, real or imagined, including those that may still lurk in the shadows.

Among whispers and rumors, there was talk of Aurora, a hypersonic, triangular plane taken from the bowels of science fiction, which seemed to be a first cousin of Lockheed Martin‘s SR-72 project, announced with great fanfare before this began. New era of hypersonic arms race.

Despite the rise of satellites, the need for aerial reconnaissance never died, as did the legend of the SR-71, which was even briefly resurrected in the 1990s to satisfy the hunger for aerial intelligence. The popular belief was that the Air Force would not let the SR-71 die without already having a worthy successor ready, warming up its engines in some secret location.

SR-91 Aurora: Many have followed its thread without finding its skein

And maybe they weren’t wrong. There are clues, threads of a larger plot, that point to evidence of an extraordinarily fast plane in those years, possibly related to Aurora.

In April 1992, on two separate occasions, journalist Steve Douglass, scanning the skies over Southern California, captured radio conversations that defied logic. A mysterious plane, with the callsign “Gaspipe,” coordinated with Edwards Air Force Base. The words captured by Douglass suggested that this craft flew at otherworldly altitudes and speeds. “You are at sixty-seven thousand [feet], eighty-one miles,” the controller indicated, and then, “Seventy miles, thirty-six thousand. Above the glide slope. Words that conjure images of a machine challenging the limits of the sky.

Was the SR-91 Aurora a real US military project?

There is no concrete evidence to confirm the existence of the SR-91 Aurora. Although it has been the subject of speculation and conspiracy theories, the lack of tangible evidence and the absence of official information suggests that it could be more of a myth or legend within the realm of military aviation.

What capabilities would a hypersonic aircraft like the SR-91 Aurora have?

If the SR-91 Aurora had existed, it is expected that it would have reached speeds exceeding Mach 5, which would have allowed it to perform reconnaissance and surveillance missions at extremely high speeds, making it difficult to detect and track by enemy air defense systems.

How is the SR-91 Aurora related to the SR-71 Blackbird?

The SR-91 Aurora is often considered the hypothetical successor to the SR-71 Blackbird, a spy plane that was a technological marvel of its time. It is speculated that the Aurora would have been designed to exceed the Blackbird’s capabilities, especially in terms of speed and operating altitude.

What advanced technologies would be expected on the SR-91 Aurora?

The SR-91 Aurora, had it been developed, would likely have incorporated advanced technologies such as high-temperature resistant composite materials, innovative propulsion systems to achieve hypersonic speeds, and stealth technologies to reduce its visibility to enemy radars.

Why do rumors about the SR-91 Aurora persist despite the lack of evidence?

Rumors about the SR-91 Aurora persist due to the public’s fascination with secret and advanced military technology. The story of the Aurora feeds into the culture of the Pentagon’s 

{https://militaryview.com/ }

30-07-2024 om 22:32 geschreven door peter  

Wat is zand en waar bestaat het eigenlijk uit? Het zijn niet alleen stenen

Door Janine

Unsplash

Of je het nu vindt op een strand, in de woestijn of als onderdeel van de regen, zand is enorm wijdverspreid in onze wereld. Maar ondanks het feit dat het veel gebruikt wordt en aanwezig is in onze samenleving, weten maar weinig mensen wat zand eigenlijk is en waar het van gemaakt is. Kortom: wat is er nog meer dan de zeer bijzondere consistentie en korreligheid ervan? En is dat echt zand in de regen? Laten we het samen ontdekken!

Wat is zand?

Zand is niets meer dan een sedimentair gesteente, dat wil zeggen gevormd door erosie van verschillende soorten gesteente en de resulterende korrels. Het is een lang en continu proces dat leidt tot het ontstaan van zand in verschillende soorten en kleuren. Om te begrijpen wat zand is, moeten we beginnen met hoe het wordt gevormd:

• Erosie van gesteenten en mineralen. Dankzij de werking van regen en wind worden de rotsen van een specifieke plaats na verloop van tijd geërodeerd en vallen ze uiteen. De minerale fragmenten die uit dit proces voortkomen, vormen het zand dat we kennen
• Ophoping van riviersedimenten. Rivieren transporteren mineralen, organische resten, puin, enzovoort naar de zee. Al deze materialen worden onderweg geërodeerd en blijven dat ook, zelfs als ze eenmaal door zeestromingen langs de kusten worden verspreid.
• Hypersaline neerslag. Naast erosie en de ophoping van sedimenten kan er ook zand ontstaan ​​door een hoge concentratie aan ionen en sterke verdamping, wat leidt tot het ontstaan ​​van hypersaline regen waarbij het zand op de grond “neerslaat”.

Zoals je kunt zien, zijn er verschillende processen die leiden tot de vorming van zand. Gedeeltelijk verklaren ze al waarom niet al het zand hetzelfde is, uitgaande van de kleur: er is bijvoorbeeld zwart vulkanisch zand en wit atolzand. Maar waar bestaat zand uit?

Waar bestaat zand uit?

Unsplash

Gewoon zand bestaat grotendeels uit silicium, in de vorm van mineralen zoals kwarts en graniet. Daarnaast zijn veldspaat, die een groot deel van de terrestrische en oceanische korst uitmaken, ook wijdverspreid in licht zand. In het donkere zand zijn echter ook grote hoeveelheden hematiet, granaat en magnetiet te vinden. Met name dit laatste mineraal is verantwoordelijk voor het “magnetische” zand dat vaak door regen wordt meegebracht.

Op basis van wat we hebben gezien, kunnen we daarom zeggen dat zand een verzameling mineralen van verschillende aard is in zeer kleine korrels, tussen 0,06 en 2 millimeter. Het is echter niet zeker dat alle mineralen waaruit het zand bestaat uit stenen afkomstig zijn: het witte zand van de Caribische eilanden bestaat ook uit microscopisch kleine resten die zijn verkregen door de erosie van schelpen en andere mariene organismen. Hun samenstelling bevat mineralen, die vervolgens bijdragen aan de vorming van dit specifieke zand.

Hoe is de samenstelling van zand in regen?

Zoals we al zeiden, kan zand ook bestaan ​​uit de minerale overblijfselen van sommige mariene organismen, waardoor het zijn karakteristieke witte kleur krijgt. Toch kunnen we ook iets soortgelijks zeggen over het zand van de Sahara, oftewel hetzelfde zand dat in sommige mediterrane landen na regen vaak op auto's blijft liggen. Het is slechts gedeeltelijk zand zoals we het tot nu toe hebben begrepen, omdat het in werkelijkheid is samengesteld uit de fossielen van vele microalgen die duizenden jaren geleden in een Afrikaans meer leefden.

Misschien weet niet iedereen dat de Sahara nog maar een paar duizend jaar een woestijn is, en dat het daarvoor de kenmerken had van prairies en savanne. In een van de meren in het gebied bevonden zich eencellige algen, diatomeeën genaamd: zodra ze gefossiliseerd waren na de vorming van de woestijn, vormden ze diatomeeënstof dat door de wind wordt getransporteerd en in de regen terechtkomt.

Zand is immers een overkoepelende term die we aan veel verschillende materialen geven en, specifieker, aan een heel specifieke korrel. Of het nu gemaakt is van kwarts of magnetiet, schelpen of gefossiliseerde algen, het is een fundamenteel materiaal voor onze hedendaagse samenleving. En niet alleen op het strand.

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30-07-2024 om 21:09 geschreven door peter  

Donkere zuurstofbron ontdekt op de bodem van de oceaan: het zou de oorsprong van het leven kunnen verklaren

Door Janine

ROV KIEL 6000, GEOMAR/Wikimedia Commons - CC BY 4.0

Zonder zuurstof zou er geen leven op aarde zijn, althans niet al tweeënhalf miljard jaar. We weten nu dat de eerste organismen die zuurstof produceerden blauwalgen waren en dat na verloop van tijd planten zich specialiseerden in de productie ervan door middel van fotosynthese. Om zuurstof te krijgen heb je zonlicht nodig, en daarom zijn er geen algen in de diepe zee die dit kunnen produceren, toch? Nou, ja en nee: het klopt dat er geen planten zijn in de diepten van de oceaan, maar tegelijkertijd hebben onderzoekers een productie van donkere zuurstof ontdekt uit bepaalde mineralen op de zeebodem. Laten we eens kijken hoe dit proces plaatsvindt en wat het betekent voor de oorsprong van het leven op aarde.

Zuurstofproducerende mineralen ontdekt op 5000 meter diepte

Anaëroob leven, dat wil zeggen leven zonder zuurstof, is zeker niet onbekend: het wordt bijvoorbeeld aangetroffen in sommige diepten in de zee, zoals de verloren stad van Lost City. Kortom, op de bodem van de oceaan is het vreemder om zuurstofproducerende mechanismen te vinden dan planten. Toch heeft een internationaal team van onderzoekers ontdekt dat er speciale metaalmineralen in de oceaanbodem zitten die zeewater kunnen splitsen in waterstof en zuurstof. Dit zijn de woorden van Andrew Sweetman van de Scottish Association for Marine Science:

Zuurstof was noodzakelijk om het aerobe leven op aarde te laten ontstaan, en we zijn er altijd van uitgegaan dat deze toevoer begon met fotosynthetische organismen. Maar nu weten we dat er zuurstof wordt geproduceerd in de diepten van de zee, waar geen licht is.

Kortom, het zou een “donkere zuurstof” zijn, juist omdat het niet wordt geproduceerd dankzij de fotosynthese van chlorofyl en zonlicht, maar door andere chemische processen die letterlijk plaatsvinden daar waar de zon niet schijnt.

De “geobatterijen” verborgen op de oceaanbodem

Goodfon

Zoals het team wetenschappers opmerkt in het onderzoek dat is gepubliceerd in het tijdschrift Geoscience, zijn het speciale polymetaalknollen die zich vormen op de oceaanbodem die zuurstof produceren. Deze formaties bevatten metalen zoals nikkel, koper, kobalt, lithium en mangaan, oftewel materialen die veel worden gebruikt bij de fabricage van elektrische batterijen. En het zijn precies “geobatterijen” waar Sweetman en zijn collega's het over hebben, nu ze zuurstofproductie hebben ontdekt in de Clarion-Clipperton-zone in het midden van de Stille Oceaan.

De onderzoekers ontdekten namelijk hoe de combinatie van roest en zout water elektriciteit kan opwekken. En er is slechts 1,5 volt nodig om zeewater te scheiden in waterstof en zuurstof, zoals werd aangetoond in een experiment: in de praktijk de spanning van een klassieke AA-batterij. De metaalknollen in de diepten van de oceaan fungeren als batterijen, of beter gezegd “geobatterijen”, voor de productie van zuurstof.

Oorsprong van aëroob leven en mijnexploitatie: de vooruitzichten op ontdekking

De ontdekking van de onderzoekers wijst in twee verschillende richtingen. De eerste is het verleden, en meer dan tweeënhalf miljard jaar geleden, het ontstaan van aeroob leven. Als rotsen inderdaad ook zuurstof kunnen produceren, wie zegt dan dat ze niet ook verantwoordelijk zijn voor het ontstaan van het leven op aarde zoals we dat nu kennen?

Tegelijkertijd is de tweede richting die van de toekomst en mijnexploitatie. Polymetaalknollen die donkere zuurstof produceren zouden tientallen jaren lang batterijen op wereldschaal van energie kunnen voorzien, maar is dat wel een goed idee? Enerzijds werd het onderzoek deels gefinancierd door het bedrijf The Metals Company, dat de metaalknollen wil extraheren. Aan de andere kant heeft diepzeemijnbouw tot verschillende problemen voor oceaanecosystemen geleid. Waaronder één die de zuurstof wil produceren die we al heel lang inademen.

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27-07-2024 om 23:50 geschreven door peter  

Een recent onderzoek, gepubliceerd in het gerenommeerde tijdschrift Science, heeft aangetoond dat klimaatverandering wereldwijd leidt tot aanzienlijke veranderingen in neerslagpatronen. Deze veranderingen kunnen resulteren in hevigere tyfoons en andere tropische stormen.

Onderzoekers onder leiding van Zhang Wenxia van de China Academy of Sciences hebben historische meteorologische gegevens geanalyseerd. Uit hun studie blijkt dat op ongeveer 75 procent van het wereldwijde landoppervlak de “neerslagvariabiliteit” is toegenomen. Dit betekent grotere schommelingen tussen nat en droog weer. De wetenschappers schrijven deze toename toe aan de opwarming van de temperatuur, die de atmosfeer beter in staat stelt om vocht vast te houden.

Veranderingen in tropische stormen

Steven Sherwood van het Climate Change Research Centre van de Universiteit van New South Wales legt uit dat de opwarmende temperaturen het vermogen van de atmosfeer om vocht vast te houden hebben vergroot. “Dit leidt tot regenachtigere perioden en drogere droge perioden”, zegt Sherwood. Hij waarschuwt dat deze trend zich zal voortzetten als de opwarming van de aarde aanhoudt, waardoor de kans op droogtes en overstromingen toeneemt.

Wetenschappers vermoeden ook dat klimaatverandering het gedrag van tropische stormen verandert. Hoewel het aantal tyfoons in sommige regio’s kan afnemen, voorspellen modellen dat de opwarming van de aarde ze sterker zal maken. Sachie Kanada van de Nagoya Universiteit in Japan benadrukt dat “een hogere temperatuur van het zeeoppervlak een gunstige voorwaarde is voor de ontwikkeling van tropische cyclonen.”

Het onderzoek benadrukt de invloed van klimaatverandering op weerpatronen in specifieke regio’s. Taiwan heeft bijvoorbeeld een toename gezien van intense tyfoons. Ook de oostkust van China is onlangs getroffen door de tyfoon Gaemi, die grote schade veroorzaakte.

Toekomstige vooruitzichten

Met de stijgende temperaturen suggereert het onderzoek dat we wereldwijd meer extreme weersomstandigheden kunnen verwachten. Feng Xiangbo van de Universiteit van Reading merkt op dat “de waterdampcapaciteit in de lagere atmosfeer naar verwachting met 7 procent zal toenemen voor elke graad Celsius temperatuurstijging.” Dit kan leiden tot meer regenval en intensievere stormen, vooral in regio’s zoals de Verenigde Staten

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26-07-2024 om 18:21 geschreven door peter  

t has been over two decades since the legacy SR-71 Blackbird was retired, and with it, enthusiasts have been awaiting its replacement from Lockheed Martin’s fabled Skunk Works. Whispers from defense circles now point to a highly classified SR-72 in the works, an unmanned hypersonic reconnaissance vehicle promising speeds above Mach 6 as the “Son of Blackbird.”

While details remain scarce, the SR-72 is believed to be a reconnaissance and strike platform building on the foundations laid by the HTV-2 hypersonic project. “It is rumored that the SR-72 hypersonic aircraft will possess superior capabilities compared to its predecessors, the X-43 and X-51 ‘WaveRider,'” said aerospace analyst Dr. John Doe.

At the heart of the SR-72 comes a dual-mode engine system that combines efficient turbofan and scramjet technologies for cruising and blistering hypersonic speeds, advanced materials in the line of carbon-carbon composites that can stand extreme heat levels way beyond the titanium skin of the SR-71.

“A major challenge for the SR-72 will be dealing effectively with the higher heat levels created by skin friction at Mach 6 and higher,” Doe added. “It’s a challenge Lockheed seems confident of overcoming.”

Many references have misnamed this project as “Darkstar” – a proposed hypersonic jet featured in the movie “Top Gun: Maverick.” According to Lt. Col. John Smith, an Air Force historian, “The process of assigning nicknames typically involves historical tradition and protocols, usually after an aircraft is accepted into service.”

Lockheed built a 69.5-foot “Darkstar” mockup for ground scenes in the film, although some parts were supplied to enable source accuracy; nevertheless, all the in-air scenes used a computer-generated version, that was modeled after an F-18.

With rivals like Russia and China pressing ahead with hypersonic programs, the SR-72 could be a strategic necessity for the United States. “It’s not just being at the pinnacle of technology; it is an existential asset for America to make sure that we are always at the forefront of aerospace capability,” Smith said.

Rumors are that Lockheed already delivered a prototype to the Air Force, but the company is reportedly targeting 2025 for the SR-72’s first flight and 2030 for operational service. As this “Son of Blackbird” starts to take shape, it will no doubt do what its iconic predecessor did more than half a century ago: push the boundaries.

The post The ‘Son of Blackbird’ Takes Shape: Lockheed’s Hypersonic SR-72 Unveiled first appeared on BuzzHint.

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23-07-2024 om 18:42 geschreven door peter  

Dit is de reden waarom de aarde langzamer draait en de dagen langer worden: volgens een onderzoek is het onze schuld

Door Janine

Unsplash

Dat de aarde steeds langzamer draait is geen mysterie, tenminste niet binnen de wetenschappelijke gemeenschap. De redenen hiervoor zijn divers en hebben te maken met de natuurlijke processen die onze planeet beïnvloeden... voor het grootste deel. Volgens recent wetenschappelijk onderzoek vertraagt de rotatiesnelheid van de aarde echter door toedoen van de mens en zijn activiteiten. Laten we eens kijken hoe dit mogelijk is en wat de gevolgen zijn voor onze samenleving.

Van de maan tot de gletsjers: een reis op een steeds trager wordende planeet

Zoals we in de inleiding zeiden, is het onderhand bekend dat de rotatiesnelheid van de aarde om haar as noch vast, noch constant is, voornamelijk als gevolg van twee verschillende processen:

• aan de ene kant vertraagt de kern van de Aarde haar rotatiesnelheid;
• aan de andere kant verwijdert de Maan zich steeds verder van de Aarde.

Dit zijn natuurlijke processen die leiden tot werkelijk oneindige veranderingen in de rotatiesnelheid van onze planeet, en dus ook in de lengte van de dagen. Door de verwijdering van de maan zal de dag van de aarde bijvoorbeeld 25 uur duren, maar over 200 miljoen jaar. Toch spreekt onderzoek uitgevoerd door het centrum ETH Zürich in samenwerking met NASA over een andere factor die de rotatiesnelheid van de aarde zou kunnen vertragen: de stijging van de temperatuur als gevolg van menselijke activiteiten.

Het verband lijkt werkelijk paradoxaal, maar het is er wel. Onderzoekers hebben namelijk ontdekt hoe hogere temperaturen een kettingreactie hebben veroorzaakt die de dagen op aarde feitelijk verlengt. Het smelten van gletsjers op Antarctica en Groenland leidt er feitelijk toe dat miljoenen kubieke meters water over het hele aardoppervlak worden verspreid, waardoor de rotatiesnelheid van de planeet effectief wordt vertraagd.

De gevolgen van de vertraging van de aarde… op aarde

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In hun eerste onderzoek, gepubliceerd in het tijdschrift PNAS, merken de onderzoekers op hoe de temperatuurstijging om antropogene redenen leidt tot langere dagen. Hetzelfde team publiceerde echter ook een tweede onderzoek in het tijdschrift GeoScience, waarin ze kijken naar hoe smeltende gletsjers bijdragen aan het veranderen van de positie van de rotatie-as van de aarde. Samen met andere verschijnselen, zoals de eerder genoemde bewegingen van de kern van de aarde, verschuift de rotatie-as elke 100 jaar ongeveer 10 meter.

De effecten die kunnen worden toegeschreven aan smeltende gletsjers en menselijke activiteiten zijn minimaal, maar er is geen reden tot vreugde. Alle verschijnselen die door de onderzoekers zijn geanalyseerd, zijn namelijk terug te voeren op natuurlijke verschijnselen, en dat hebben we gezien: de maan die afstand neemt, het effect van de getijden, de binnenkern en haar bewegingen, enzovoort. In zo'n beeld speelt echter ook de hand van de mens een rol en kan leiden tot plotselinge versnellingen van deze processen.

De gevolgen van de vertraging van de aarde... voor de mens

De interne en externe processen op aarde zijn daarom meer met elkaar verbonden dan we denken: zoals we hebben gezien, kunnen ze elkaar beïnvloeden,  maar ook de menselijke activiteiten die bijdragen aan het veroorzaken ervan. Hoewel de vertraging van de rotatiesnelheid van de aarde momenteel minimaal is en de dagen slechts fracties van een seconde langer worden, zijn de gevolgen voor de mens al aanzienlijk.

De tijdmeting van de mens is gebaseerd op uiterst nauwkeurige atoomklokken. Deze precisie wordt echter in gevaar gebracht door de interactie tussen de verschillende factoren die bijdragen aan het verlengen van de dagen op aarde. Het risico is dat we minder nauwkeurige GPS hebben, met alle gevolgen van dien voor alle menselijke activiteiten.

Aan de andere kant: als de vertraging tot 2000 tussen de 0,3 en 1 milliseconde per eeuw lag, zitten we nu op ongeveer 1,3 milliseconden per eeuw, maar dit lijkt voorbestemd om te stijgen. Het is een neerwaartse spiraal waar we de afgelopen decennia steeds meer vertrouwd mee zijn geworden... en die we nog kunnen vertragen als we tijdig handelen.

Source:

{ https://www.curioctopus.nl/ }

19-07-2024 om 21:14 geschreven door peter  

Wetenschappers van een laboratorium in het Franse Marseille hebben gewaarschuwd voor de mogelijkheid van een nieuwe pandemie in de toekomst. Deze zou immers kunnen worden veroorzaakt door een virus dat al meer dan 30.000 jaar bevroren is.

Microben in het noordpoolgebied zouden de oorzaak kunnen zijn, nadat de opwarming van de aarde, de toegenomen menselijke activiteit en de aanwezigheid van schepen in de regio het ontdooi- en smeltproces versnellen.

Volgens de onderzoekers is de kans groot dat deze en andere virussen, als het ontdooiproces doorgaat, zich vrij zullen verspreiden en uiteindelijk nieuwe ziekten veroorzaken.

Dit ‘zombievirus’ werd door laboratoriumonderzoekers ontdekt in een laag Siberische permafrost die duizenden jaren bevroren was in het noordwesten van Siberië.

Het nieuws werd in The Guardian becommentarieerd door de Nederlandse viroloog Marion Koopmans, die beweerde dat “we niet weten welk virus zich in de permafrost bevindt. Maar ik denk dat er een reëel risico bestaat dat er één virus is dat een epidemie kan veroorzaken, bijvoorbeeld een oude vorm van polio. We moeten aannemen dat zoiets zou kunnen gebeuren”, waarschuwde ze.

(SR and FM for Tagtik/Source: The Guardian/Illustration: Pixabay)

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19-07-2024 om 20:22 geschreven door peter  

Wetenschappers van een laboratorium in het Franse Marseille hebben gewaarschuwd voor de mogelijkheid van een nieuwe pandemie in de toekomst. Deze zou immers kunnen worden veroorzaakt door een virus dat al meer dan 30.000 jaar bevroren is.

Microben in het noordpoolgebied zouden de oorzaak kunnen zijn, nadat de opwarming van de aarde, de toegenomen menselijke activiteit en de aanwezigheid van schepen in de regio het ontdooi- en smeltproces versnellen.

Volgens de onderzoekers is de kans groot dat deze en andere virussen, als het ontdooiproces doorgaat, zich vrij zullen verspreiden en uiteindelijk nieuwe ziekten veroorzaken.

Dit ‘zombievirus’ werd door laboratoriumonderzoekers ontdekt in een laag Siberische permafrost die duizenden jaren bevroren was in het noordwesten van Siberië.

Het nieuws werd in The Guardian becommentarieerd door de Nederlandse viroloog Marion Koopmans, die beweerde dat “we niet weten welk virus zich in de permafrost bevindt. Maar ik denk dat er een reëel risico bestaat dat er één virus is dat een epidemie kan veroorzaken, bijvoorbeeld een oude vorm van polio. We moeten aannemen dat zoiets zou kunnen gebeuren”, waarschuwde ze.

(SR and FM for Tagtik/Source: The Guardian/Illustration: Pixabay)

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19-07-2024 om 20:22 geschreven door peter  

Klimaatverandering veroorzaakt een onverwachte en fundamentele planetaire verandering

Een verrassend samenspel tussen het smelten van ijs en natuurkunde betekent dat de dagen van de aarde langer worden

BIJ LAUREN LEFFER

IJssmelt aangespoord door door de mens veroorzaakte opwarming van de aarde wijzigt de massaverdeling van onze planeet, vertraagt uiteindelijk de rotatie van de aarde en verlengt de 24-uursdag, volgens een studie gepubliceerd op 15 juli in het tijdschrift Proceedings van de National Academy of Sciences. Eerder onderzoek heeft vergelijkbare bevindingen gedaan, maar de nieuwe studie suggereert dat klimaatverandering een grotere impact heeft op de daglengte dan eerder werd gedacht.

Als het gebruik van fossiele brandstoffen en de uitstoot van broeikasgassen blijven toenemen in een algemeen genoemd scenario met hoge opwarming, bekend als RCP 8.5, dan zou klimaatverandering een grotere invloed kunnen hebben op de rotatie en daglengte van de aarde dan de maan, volgens de nieuwe bevindingen.

Veel factoren hebben een klein maar significant effect op de daglengte, waaronder de beweging van magma in de vloeibare kern van de aarde, windfluctuaties en de stroming van water op het oppervlak van onze planeet. Zoals het is, creëert de maan getijden die heen en weer wrijving produceren die de rotatie van onze planeet vertraagt. Op de schaal van de geologische tijd heeft dit maaneffect de grootste bijdrage geleverd aan veranderingen in de daglengte in de geschiedenis van onze planeet. Toch is de door de mens veroorzaakte opwarming van de aarde bezig met een inhaalslag.

De aarde is geen perfecte bol, het is "afgeplat", wat betekent dat het licht samengedrukt is langs de evenaar in een subtiele 3D-ovale vorm. Naarmate de ijskappen van Groenland en Antarctica smelten, beweegt er meer water en massa van de polen naar de evenaar. Dit maakt de aarde effectief verder plat, waardoor het midden nog breder en zwaarder wordt dan de boven- en onderkant, waardoor de rotatie enigszins wordt vertraagd als gevolg van de toegenomen traagheid. "Het is net als wanneer een kunstschaatsster een pirouette maakt, waarbij ze eerst haar armen dicht bij haar lichaam houdt en ze vervolgens uitstrekt", zei senior onderzoeker Benedikt Soja, hoogleraar ruimtegeodesie aan de ETH Zürich in Zwitserland, in een persverklaring. Met uitgestrekte armen zou de kunstschaatser vertragen, en twee eeuwen aan observatiegegevens en modellen suggereren dat onze planeet dat ook is.

Onderzoekers berekenden het smelten van ijs en de bijbehorende veranderingen in de afgeplatheid van de aarde met behulp van observatiegegevens die sinds 1976 zijn verzameld en modelleerden reconstructies en projecties van 1900 tot 2100. In de 20e eeuw ontdekten ze dat klimaatverandering de dag tussen 0,3 en 1,0 milliseconden verlengde. Sinds 2000 is de snelheid van door klimaatverandering veroorzaakte dagverlenging echter versneld tot ongeveer 1,33 milliseconden per eeuw. In het RCP 8.5-scenario met hoge emissies voorspellen de wetenschappers dat de snelheid van dagverlenging zou verdubbelen tot ongeveer 2.62 milliseconden per eeuw, waarmee officieel de getijdenwrijving van de maan zou worden overtroffen als de belangrijkste langetermijnkracht die op de daglengte van de aarde inwerkt.

Een paar milliseconden per eeuw klinkt misschien als kruimels in vergelijking met de universele taart, maar het kan oplopen tot dagen die uren langer zijn gedurende miljarden jaren. Op de kortere termijn hebben de door het klimaat veroorzaakte verschuivingen invloed op nauwkeurige tijdregistratie, die wordt gebruikt om nauwkeurige en soepele GPS-navigatie, wereldwijde communicatie, elektriciteitsnetten en financiële systemen te behouden. Ook de verkenning van de ruimte kan door de verandering worden beïnvloed, omdat zelfs kleine afwijkingen in rotatie en positie op aarde kunnen leiden tot grote misrekeningen als het gaat om het navigeren en corrigeren van het landen van een sonde over grote afstanden elders in het zonnestelsel.

Een verwante studie van dezelfde groep onderzoekers die op 12 juli werd gepubliceerd, beoordeelde niet alleen de rotatiesnelheid, maar ook de beweging en locatie van de as van de aarde. Soja en zijn collega's ontdekten dat dezelfde herverdeling van water en massa, veroorzaakt door smeltende poolkappen, bovendien de rotatie-as van de planeet verschuift - mogelijk met een paar meter per eeuw.

Er zijn beperkingen aan beide onderzoeken. RCP 8.5 wordt bijvoorbeeld over het algemeen beschouwd als een verouderde en onwaarschijnlijke projectie voor toekomstige opwarming en gemodelleerde gegevens gaan gepaard met een zekere mate van onzekerheid. Toch laten de twee wetenschappelijke artikelen zien hoe diep de gevolgen van klimaatverandering weerklinken.

"Wij mensen hebben een grotere impact op onze planeet dan we beseffen", aldus Soja in het persbericht. "Dit legt natuurlijk een grote verantwoordelijkheid op ons voor de toekomst van onze planeet."

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18-07-2024 om 22:23 geschreven door peter  

Do Tachyons Exist as Particles?

Tachyons are hypothetical particles that always travel faster than light. Until recently, they were generally regarded as entities that did not fit into the special theory of relativity. According to a new paper in the journal Physical Review D, these faster-than-light particles are ‘not only not ruled out by the theory, but allow us to understand its causal structure better.’

An AI impression of tachyons.

“Motion at speeds beyond the speed of light is one of the most controversial issues in physics,” said Professor Andrzej Dragan from the University of Warsaw and National University of Singapore and his colleagues.

“Hypothetical particles that could move at superluminal speeds, called tachyons, are the enfant terrible of modern physics.”

“Until recently, they were widely regarded as creations that do not fit into the special theory of relativity.”

“At least three reasons for the non-existence of tachyons within quantum theory were known so far,” they added.

"The first is the ground state of the tachyon field was supposed to be unstable, which would mean that such superluminal particles would form avalanches.”

“The second is a change in the inertial observer was supposed to lead to a change in the number of particles observed in his reference system, yet the existence of, say, seven particles cannot depend on who is looking at them.”

“The third reason is the energy of the superluminal particles could take on negative values.”

“The difficulties with tachyons so far had a common cause,” the physicists said.

“It turned out that the boundary conditions that determine the course of physical processes include not only the initial state but also the final state of the system.”

“To put it simply: in order to calculate the probability of a quantum process involving tachyons, it is necessary to know not only its past initial state but also its future final state.”

“Once this fact was incorporated into the theory, all the difficulties mentioned earlier completely disappeared and tachyon theory became mathematically consistent.”

“It’s a bit like Internet advertising — one simple trick can solve your problems,” Professor Dragan said.

“The idea that the future can influence the present instead of the present determining the future is not new in physics.”

“However, until now, this type of view has at best been an unorthodox interpretation of certain quantum phenomena, and this time we were forced to this conclusion by the theory itself.”

“To make room for tachyons we had to expand the state space.”

“We also predict that the expansion of the boundary conditions has its consequences: a new kind of quantum entanglement appears in the theory, mixing past and future, which is not present in conventional particle theory.”

The team’s paper also raises the question of whether tachyons described in this way are purely a mathematical possibility or whether such particles are likely to be observed one day.

“Tachyons are not only a possibility but are, in fact, an indispensable component of the spontaneous breaking process responsible for the formation of matter,” the authors said.

“This hypothesis would mean that Higgs field excitations, before the symmetry was spontaneously broken, could travel at superluminal speeds in the vacuum.”

• Jerzy Paczos et al. 2024. Covariant quantum field theory of tachyons. Phys. Rev. D 110 (1): 015006; doi: 10.1103/PhysRevD.110.015006
• This article is a version of a press-release provided by the University of Warsaw

{ https://www.sci.news/ }

12-07-2024 om 20:31 geschreven door peter  

Nieuw wezen ontdekt in de Golf van Alaska: het heeft meer dan 200 poten en een zeer belangrijke rol

 Door Janine

Freepik

Er is een nieuw wezen ontdekt in de diepten van de oceaan in de Golf van Alaska, voor de westkust van Canada. Laten we samen zijn merkwaardige eigenschappen en de sleutelrol die het in de diepten speelt ontdekken.

Nieuwe soort zeekomkommer ontdekt

Een nieuw waterdier, dat leeft op de bodem van de Stille Oceaan in de Golf van Alaska, is ontdekt door een team mariene biologen. Het is een soort met merkwaardige eigenaardigheden: het heeft tweehonderd poten en zijn kleur is roze. Het team, bestaande uit onderzoekers Francisco Solís Marín, Andrea Caballero Ochoa en Carlos Conejeros-Vargas, professoren aan het Instituut voor Oceaanwetenschappen en Limnologie in Mexico, presenteerde de ontdekking en beschreef het als een nieuw wezen dat over de zeebodem kruipt.

Maar wat is de naam van dit wezen wat nog nooit gezien was? Het is een onbekende variant van de zeekomkommer, paarsroze en bleek van kleur, met een lang, slijmerig lichaam uitgerust met 214 poten die in een zigzagpatroon zijn geplaatst en op kleine buisjes lijken. De wetenschappelijke naam in de studie gepubliceerd in Biodiversity Data Journal is Synallactes, maar de eenvoudigere bijnaam is McDaniel zeekomkommer.

De McDaniel zeekomkommer speelt een belangrijke rol voor de oceaan

Biodiversity Data Journal

De meer onofficiële naam werd geïnspireerd op Neil McDaniel, een deskundige natuuronderzoeker uit Canada die zich toelegt op de studie van zeedieren zoals koralen, anemonen, sponzen en zeekomkommers. Net als de andere exemplaren van zijn soort brengt de McDaniel zijn bestaan kruipend door op zoek naar voedsel. Deze wezens zijn te vinden op dieptes variërend van ongeveer 21 tot 426 meter. Om zich te voeden gebruiken ze hun talrijke tentakels, waarmee ze sedimenten van de zanderige zeebodem verzamelen, waaronder algen en verschillende soorten afval.

Hun activiteit, zo ontdekten de onderzoekers, blijkt zeer nuttig te zijn: zeekomkommers dragen over het algemeen aanzienlijk bij aan het mariene ecosysteem, omdat ze de onbetwiste "schoonmakers" zijn van afval dat in de diepte aanwezig is. Wat ze binnenkrijgen, wordt gefilterd en uitgestoten in de vorm van schoner zand: juist hun dieet zorgt er dus voor dat de zeebodem minder vervuild en vrij is van residuen. De vertering van zeekomkommers zorgt bijvoorbeeld voor een toename van calciumcarbonaat, wat nuttig is voor het gedijen en gezond blijven van koralen.

Kenmerken van de McDaniel zeekomkommer

De nieuwe soort McDaniel, met zijn zachte maar over het algemeen stevige en ruwe lichaam, is tussen de 22 en 30 cm lang, waarbij het onderste deel van het lichaam iets lichter van kleur is. Wat hem onderscheidt van andere zeekomkommers is het aantal papillen op zijn rug. Twee zigzaggende rijen van elk 62 buisvoeten en twee andere van elk 45 poten bevinden zich op het onderste deel van het lichaam en helpen hem om zich te verplaatsen over zanderige en rotsachtige oppervlakken in het noordoosten van de Stille Oceaan.

Het totale aantal zeekomkommers, die ook voorkomen in de Marianentrog, neemt af, maar biologen hopen dit tegen te gaan door meer bekendheid te geven aan het belang van deze wezens in oceaanecosystemen. Hun werk is weliswaar belangrijk, maar niet genoeg om het probleem van de onderwateromgeving op te lossen, maar een grote gemeenschap kan zeker een sleutelrol spelen in het welzijn van dit leefgebied.

Synallactes mcdanieli sp. nov. Holotype RBCM 995-00131-001. Ossicles of dorsal papillae A tri-, quadri- and pentaradiate tables; B spiny rods, with the lateral spines (sometimes branched); C long, thin, smooth, straight or curved rods with perforated ends.

  Part of: Solís Marín F, Caballero Ochoa A, Conejeros-Vargas C (2024) Synallactes mcdanieli sp. nov., a new species of sea cucumber from British Columbia, Canada and the Gulf of Alaska, USA (Holothuroidea, Synallactida). Biodiversity Data Journal 12: e124603. https://doi.org/10.3897/BDJ.12.e124603 

{ https://www.curioctopus.nl/ }

07-07-2024 om 18:45 geschreven door peter  

Speeding Towards a Crucial Tipping Point

Here's why the old models got it so wrong.

BY LAUREN LEFFER

Moelyn Photos/Moment/Getty Images

“It’s incredibly worrying,” said Bethan Davies, lead study author and a glaciologist at Newcastle University in England in a statement. “The feedback processes this sets in motion [are] likely to prevent future glacier regrowth, potentially pushing glaciers beyond a tipping point into irreversible recession.”

More than 20 percent of global sea level rise results from mountain glaciers and ice cap melt and Alaska’s glaciers are already the largest single contributor among that portion. The new findings indicate that the state’s future contributions to rising tides may soon be baked-in, and impossible to prevent.

Davies and her co-authors combined historical aerial photographs, geologic data on the most recent glacial maxima, and satellite images to specifically quantify volume and area loss at one site, which likely carries implications for others. They focused their analysis on Juneau Icefield, a sprawling expanse composed of about 1,000 glaciers covering about 1,500 square miles on the Alaska/British Columbia border, and assessed how the formation changed between 1770 and 2020.

The scientists found some alarming trends. Following the end of the “Little Ice Age” that spanned from about 1300 to 1750, ice loss was relatively consistent between 1770 and 1979. During that period, Juneau Icefield lost between .65 and 1.01 cubic kilometers (0.16 to 0.24 cubic miles) of ice each year. Between 1979 and 2010, that rate increased to 3.08 to 3.72 cubic kilometers of ice loss annually. From 2010 to 2020, the rate of ice loss doubled in just a decade, rising to about 5.91 cubic kilometers per year. Zooming in on a narrower and more recent time period, losses accelerated even further between 2015 and 2020.

All of this has unfolded against the backdrop of increasing atmospheric greenhouse gas concentrations and rising average temperatures. Summer temperatures at Juneau Icefield were about 1 degree Celsus warmer, on average, from 2001 to 2020 than they were from 1941 to 1970. The mean winter temperature for the same time period is up more than 2 degrees C, lengthening the annual period of melt.

As of 2019, 100 percent of the glaciers mapped at Juneau Icefield were receding and 108 had disappeared completely. The total ice loss since the Little Ice Age maximum is estimated to be about 24.25 percent of the icefield’s volume. In addition to the loss of ice volume and area, the remaining ice field is becoming increasingly fragmented and vulnerable.

As the melt eats away at the ice field and its glaciers, several knock-on processes are triggered which can lead to feedback loops that, in turn, produce more melting. For one, Juneau Icefield (as with many Alaskan icefields) is relatively flat, so it’s losing volume all over. As this happens, it becomes less thick and, over time, the surface of the ice gets closer to sea level. At lower elevations, the air is warmer, and melting increases.

Another feedback loop occurs when fresh snow accumulation is reduced at lower altitudes, as the icefield surface gets farther away from the snowline. With less fresh snow, the icefield surface becomes dirtier and less reflective. These darker surfaces absorb more heat and additional melting ensues. Fragmentation that exposes rocks and gravel also reduces the reflectivity (or “albedo”) of the icefield, and enables hotter air to penetrate deeper into glaciers.

Each of these processes individually is “destabilizing”, write the study authors, and together they are even worse news. Scientists rely on mathematical and computer models to try to predict how ice losses are set to unfold under climate change. However, existing icefield models often don’t consider these sorts of feedback loops and fail to capture the depth, breadth, and speed of planetary modification underway.

Currently, models suggest that Juneau Icefield should be losing ice linearly through 2040, with losses only accelerating after 2070, but the new study indicates those models are flawed. “Current glacier projections may be too small and underestimate glacier melt in the future,” Davies said. If we want to understand what the coming decades hold, we’ll have to pay closer attention to the past.

{ https://www.inverse.com/ }

07-07-2024 om 16:14 geschreven door peter  

Scientists Have Found a New Climate Tipping Point

Hotter oceans are set to trigger a feedback loop of runaway melting.

BY LAUREN LEFFER

 

Stocktrek Images/Getty Images

Yet most current-day models of sea level rise don’t indicate we’re headed towards anything like 65 feet of sea level rise in the near-future, even at 2 to 3 C of warming. The discrepancy between past and future projection has been an unsettling mystery for climate and ocean scientists for years. Many researchers in the field think the answer comes down to incomplete and inaccurate models. New study findings could be part of solving the puzzle.

The world’s ice sheets are subject to a never-before-identified and worrying climate tipping point, according to the study published June 25 in the journal Nature Geoscience. The discovery, based on a novel mathematical and computer model of ice melt and seawater movement, means we could be in for far more sea level rise in coming years than previously forecasted. “Our projections of sea level rise might be significant underestimates,” said Alex Bradley, lead researcher and a climate scientist with the British Antarctic Survey (BAS), in a press statement.

Here’s how: Coastal ice sheets are made up of floating shelves and grounded sections. This is where ice sits directly on land. In between is the so-called “grounding zone.” Ocean water rushing beneath the grounding zone triggers melt, which can change the structure of the ice mass, subsequently allowing more water to intrude farther and faster in a feedback loop, according to the new analysis. Generally, models assume that all ice sheets have a point of stability where they’ll stop receding, based on the topography of the land that underlies them. Thanks to gravity, it’s hard for water to flow uphill. But the new assessment suggests that, with enough warming and melt progression widening the grounding zone, ocean water will be able to continue intruding deep beneath ice sheets, even upslope.

Climate tipping points occur when a relatively small shift in something like temperature or atmospheric carbon rapidly leads to an outsized impact. In this case, climatologists behind the new research found that subtle increases in ocean warming could lead to very large ice losses and sea level rise. For every ice sheet, including the pivotal expanse of ice that covers Antarctica and contains about 6 million cubic miles of water, there is a point of ocean warming where that feedback loop of melt, structural shifts, and more melt will become a “runaway” process. At a certain ocean temperature, refreezing ice can’t make up for the losses, triggering “dramatic changes” in ice sheet behavior, according to the researchers’ analysis.

Making matters worse, the researchers suggest there will be little warning that Antarctica and other ice sheets are nearing their individual grounding-zone tipping points. Such changes will be “hard to detect…until the tipping point is passed,” they write. The resulting, fated sea level rise would unfold relatively quickly, on the order of decades to centuries.

“This is missing physics, which isn’t in our ice sheet models,” Bradley said, adding that BAS scientists are now working to incorporate it into revised models.

Surprisingly, the Thwaites “Doomsday Glacier” is less at risk of passing this particular tipping point than other ice shelves, per the assessment. (Though seawater intrusion is causing Thwaites to melt faster than expected, according to another recent study.) But other shelves like the Pine Island glacier, which is already Antarctica’s largest contributor to sea level rise, are highly susceptible.

The analysis offers just one initial and simplified model, which doesn’t account for all of the factors relevant for ice sheet melt. For instance, tides aren’t part of the researchers’ equations. And the scientists don’t expect melt triggered by intrusion to proceed indefinitely. Nonetheless, the findings are alarming.

“With every tenth of a degree of ocean warming, we get closer and closer to passing this tipping point, and each tenth of a degree is linked to the amount of climate change that takes place,” Bradley told The Guardian. “We need very dramatic action to restrict the amount of warming that takes place and prevent this tipping point from being passed.” The only way to stop such melt in its tracks is to halt the largest single driver of climate change and rapidly transition away from burning fossil fuels.

{ https://www.inverse.com/ }

01-07-2024 om 21:44 geschreven door peter  

Do you have a burning desire to spend all your money to travel to distant jungles to strike up convos with screeching monkeys in trees?

I’m not dressing up posts with header images anymore. Clean and simple. But, for this one, I’ll make an exception. It’s funny, and it drives the point home.

For the past couple of years, I’ve been intrigued by the sudden government-sanctioned “limited hangouts” on UFOs. Some folks, like Tucker Carlson, have latched onto them, prompting me to shake my head in disbelief. Here’s the deal: for 35 years, I’ve held firm that there are no UFOs, never have been, and never will be. Logic is on my side, and I’ll outline why below.

I’m giving out #31 of my 114 No-Pill Advantages. Originally drafted 35 years ago, it has undergone a few revisions, but the core logic and conclusion remains unchanged. As you read through this, keep in mind it was written decades ago. Ask yourself: has anything fundamentally changed? Are there actual bodies now? Artifacts like a phaser or some tricorder gadget? An actual spacecraft dissected? Nope, just the same old grainy photos and blurry videos.

… In an age where everyone has had a phone in their pocket for 20 years, and high-resolution cameras for at least the last decade, where are the clear photos? Modern phones excel even in low-light conditions, yet I’ve never seen a decent, high-res shot of a supposed UFO. Not one.

What gives rise to this post is that I got wind of an article in The Hill. It’s a ridiculous piece, based on a so-called “Harvard study” that I can’t even find. It’s just a bunch of nonsense, really. I don’t even want to dignify it. What it screams to me is the same old pattern in society: blind deference to so-called authorities.

… You know why people really have a problem with totalitarian regimes? What’s the chief distinction between the U.S. government or the EU, or whoever, and a totalitarian regime? The chief distinction is that a totalitarian regime doesn’t have a “God,” doesn’t have a higher authority. People bristle at the idea that there’s no imaginary-friend-personally-looking-out-for-you check on their government’s authority.

So, in the case of the U.S., we have a secular check, which is the Constitution and the separation of powers. It kinda works—except when it usually doesn’t. But then you have the church, right? You can’t really be a successful politician in America without making your obeisance to some form of God. For America, that pretty much has to be Jehovah or Jesus. In countries like where I live, Thailand, you gotta be a Buddhist.

But here’s the kicker: the UFO thing represents a kind of backup authority. Governments need people who have faith in a higher power, higher intelligence, or higher knowledge. If God or whatever manifestation of God isn’t working out quite as well as they’d hoped, they roll out the space aliens. Eventually, they’ll reveal themselves. And of course, since they could get here, they must know everything. They know where we came from. They know the origin story. They’ll be able to tell us all sorts of stuff. Just have faith in that.

They’re looking out for us.

It’s the same faith as religion. Exactly the same on fundamental levels. And that’s what I keep harping on: the lack of agency among individual human beings. People are supposed to be their own authority. Their job in life is to look around, assess what’s real, and distinguish it from what’s not real. Act accordingly. Make mistakes, learn from them, and go forth to do better and better. Be a little less wrong about everything every day, rather than holding up a book written 2000 years ago and claiming it’s right about everything.

OK, enjoy this piece. Keep in mind it was drafted 35 years ago. Ask yourself: Does anything we currently think we know about UFOs make anything said here false? If you’re honest, you’ll say no, it doesn’t. So what’s the big hullabaloo all about?

As with all forms of mysticism, the acceptance of myths ranging from astrology and UFOs to religion and the concept of God can have detrimental effects on an individual’s thinking and integration processes. In fact, this acceptance can severely hinder a person’s personal power, productive competence, financial well-being, psychuous pleasures, and long-range happiness.

When one embraces mysticism, they often surrender critical thinking and rationality in favor of beliefs that lack empirical evidence or logical reasoning. By doing so, they limit their ability to objectively analyze and understand the world around them. This impaired thinking can prevent individuals from making informed decisions, solving problems effectively, and adapting to new situations.

Moreover, the integration processes of a person, which involve synthesizing different aspects of their life and experiences, are also compromised. The acceptance of myths can create cognitive dissonance and conflicts within an individual’s belief system, leading to a fragmented sense of self and difficulty in establishing coherent values and principles. This lack of integration can hinder personal growth and development, as well as negatively impact relationships and social interactions.

Furthermore, embracing mysticism can have adverse effects on an individual’s personal power and sense of agency. By relying on external forces such as astrological predictions or supernatural entities, people may feel disempowered and dependent on factors beyond their control. This can lead to a sense of helplessness and passivity, preventing individuals from taking charge of their own lives and pursuing their goals with determination.

In addition, the acceptance of myths can impede productive competence. Instead of focusing on acquiring practical skills, knowledge, and expertise, individuals may invest their time and energy in pursuits that lack a solid foundation in reality. This diversion of resources can hamper professional growth, limit career opportunities, and hinder financial well-being.

Moreover, the pursuit of psychuous pleasures, which encompass both physical and emotional gratification, can be compromised by the acceptance of myths. By attributing supernatural or cosmic significance to experiences, individuals may overlook the genuine sources of joy and fulfillment in their lives. This can lead to a perpetual search for external validation or transcendent experiences, neglecting the simple pleasures and meaningful connections that can bring long-lasting happiness.

Ultimately, the acceptance of myths in various forms of mysticism can have far-reaching consequences. It can cripple an individual’s thinking and integration processes, limiting their personal power, productive competence, financial well-being, psychuous pleasures, and long-range happiness. By embracing critical thinking, rationality, and evidence-based beliefs, individuals can open themselves up to a world of possibilities, empowering themselves to live a more fulfilled and successful life.

Many popular myths rely on so-called “scientific” evidence to create an illusion of credibility. Supporters of astrology argue that the incredibly weak celestial forces that interact with humans have an impact on their thoughts, actions, behavior, and fate. They use the example of how the moon’s gravitational forces cause ocean tides as “proof.” However, facts and rational thinking demonstrate that humans are solely responsible for their own destiny. A person’s mind has the ability to overpower all the forces of nature combined. In a society that values freedom, an individual’s conscious mind has much more control over their future than all the obvious, direct influences of nature, government, and religion combined.

One’s destiny is primarily determined by their own choices rather than their surroundings. With the exception of natural disasters or oppressive totalitarian regimes, the impact of nature and social environment on an individual’s long-term future is minimal or negligible when compared to the power of the rational conscious mind.

To allow one’s future to be impacted by natural forces like the weather, wind, or rain would diminish the power of their mind and actions. However, astrologers take it a step further by suggesting that even the faintest celestial forces from outer space can influence human beings and their minds. This perspective undermines the potential of the human mind, eroding confidence and self-esteem. Furthermore, those who allow themselves to be controlled or influenced by nonexistent forces like the God myth face even more serious consequences in their confidence and self-esteem.

There is a common misconception among many individuals that the authority of government and religion surpasses their own power. This belief is understandable, given the historical destructive impact these forces have had on humanity. However, it is important to recognize that government and religious influences, although often destructive, do not have to control an individual’s present or future. By employing critical thinking and rational decision-making, one can typically evade or reduce the impact of government and religion on their personal lives, enabling them to live independently, productively, and happily.

Sometimes, the devastating impacts on individuals can be caused by various entities such as the government, religion, or even natural occurrences like earthquakes, floods, and tornadoes. The government has the power to seize or exploit someone’s belongings, as well as imprison or unjustly kill innocent individuals. Religion has the potential to harm a person’s mental well-being and overall happiness. Additionally, when the church wields direct political influence, it has historically inflicted torture and death upon countless innocent people, exemplified by instances like the Dark Ages, Inquisitions, Jonestown, Ayatollah Iran, Witch Trials, and the crusades. However, none of these potential or actual forces essentially govern or determine the course of human lives or destiny. The human mind, in conjunction with the choices made throughout an individual’s life, ultimately shapes the life and future of a productive person, unless they are directly incapacitated or destroyed by government or religious forces.

Believing in “scientific” myths like UFOs, which are unidentified flying objects from intelligent outer space, can have negative effects on a person’s self-esteem and their ability to experience pleasure and happiness. Similar to astrology and other forms of “scientific” mysticism[1], UFO advocates use a scientific-sounding foundation to create the illusion of credibility. They often take the valid hypothesis that there are millions of Earth-like planets in outer space with advanced civilizations and technology beyond our own. These civilizations would likely be capable of communication or even traveling across vast distances to reach Earth, as their conscious beings would have achieved biological immortality a long time ago.

The aforementioned hypotheses hold statistical validity and are likely factual. Based on statistical data, it is plausible to conclude that there are millions, if not billions, of Earth-like planets harboring intelligent life forms across the universe. It is highly probable that a significant number of these civilizations, being far more advanced than ours, have the capability to establish contact with Earth. However, logical reasoning and statistical evidence suggest that these civilizations would not think to contact Earth or any number of other millions of civilizations on par with Earth’s advancement, or more primitive.

The primary rationale for holding the belief that Earth has never been contacted by any extraterrestrial civilization is the lack of any compelling evidence suggesting such an encounter. Any purported evidence that has surfaced thus far has been deemed dubious, fraudulent, or scientifically invalid. Had there been actual contact with intelligent extraterrestrial life, the proof would have been both instantaneous and overwhelmingly convincing. Take, for instance, the highly sophisticated artifacts that would inevitably be left behind by any civilization devoid of mysticism, yet possessing the necessary technological prowess and energy to establish contact with Earth.

Surely, numerous highly sophisticated civilizations within the cosmos possess the technology to reach and communicate with Earth. However, using the following rationale, it is unlikely that they would make contact. The advancement of any civilization is directly proportional to the amount of energy it can harness. This energy capacity is a direct reflection of scientific knowledge and technological development. The energy necessary for interstellar communication and travel far outweighs Earth’s total energy capacity, given our current technological state. Therefore, a civilization capable of reaching us would be significantly more advanced. This implies that such a civilization would have surpassed the Nuclear-Decision Threshold. This critical juncture is one that every advanced civilization must navigate successfully to ensure survival. Currently, our civilization is at this threshold. The Nuclear-Decision Threshold represents the stage at which a civilization’s energy, knowledge, and technology have evolved to the extent that they can produce enough artificial energy (such as nuclear energy) to obliterate all life on their planet. From this point, all civilizations must select one of two paths:

(1) Follow a philosophical system that is irrational, altruistic, and Platonistic, where authoritarian initiatory force persuades others to back “higher” mystical causes that support the deceptive livelihoods of parasitical elites. Such systems will ultimately result in either complete nuclear warfare[2] or a regression to an anti-technological Dark Ages where the majority of knowledge and technology are lost. Regardless of the outcome, the majority of the world’s population will perish and civilization will be destroyed due to the manipulation of pointless mysticism to provide false power and deceptive livelihoods to those who destroy value.

(2) Adopt or transition to a rational, business-oriented, Aristotelian philosophical system that excludes the use of initiatory force. This system enables civilization to securely progress past the Nuclear-Decision Threshold.

Therefore, any civilization that has significantly surpassed this threshold would naturally exist in a logical Aristotelian society (logic: 1+1=2; identity: A is A). This would imply a free-market business society where initiating force is eliminated as it’s uncompetitive, powerless, and immoral. In such a progressed society, all forms of mysticism would naturally have been discredited and abandoned as foolish and harmful. This business-oriented society would be devoid of politicians, theologians, mooching leaches, oppressive governments, quasi-state fascistic Big Corp, and other exploiters and parasites. Actions would be grounded in reality-based logic exercised by free individuals living harmoniously and competitively in line with their sensible best interests.

In a highly advanced society, there would be no logical rationale or discernible advantages to justify the excessive time and energy needed to communicate with Earth or comparable extraterrestrial civilizations. Such an endeavor would neither be scientifically intriguing nor profitable for a civilization possessing such advanced knowledge and technology.

In other words, once a civilization reaches a point of technological progress where it can communicate with other civilizations, the incentive or desire to do so, along with the advantages gained from it, may decrease. This is because such societies would naturally be reasonable and self-serving. People within these societies would be capable of satisfying all their material, emotional, and developmental needs within a reasonable geographic boundary, even though they have the capacity to explore further into space. In addition, these developed civilizations could have access to an imagined universal interstellar computer network. Such a network would manage and provide all crucial knowledge for sharing among developed, advanced civilizations. It would require no access keys. Attaining the advanced knowledge to detect it would, in itself, be the access key.

To sum up, it’s likely that thousands or even millions of highly advanced civilizations exist in the cosmic realm, equipped with the technology to reach out to Earth. However, due to their non-altruistic, profit-driven nature, these societies would lack a rational reason or incentive to invest their time and energy in such contact.[3]

Our civilization would need to transition from our present Platonistic/altruistic philosophical foundation to an Aristotelian/rationally self-interested, business-like philosophical foundation to significantly progress beyond our existing Nuclear-Decision Threshold.

Interestingly, our current stage of civilization allows us to reap substantial economic, technological, and scientific rewards from studying outer space and venturing beyond our solar system. By transitioning to a rational and logical society, our civilization will significantly surpass the Nuclear-Decision Threshold. This will result in our knowledge, technology, and well-being advancing at such a rapid and extensive pace that when we have the energy capacity to communicate with civilizations in distant outer space, the logical reasons or incentives for such contact (economic, social, scientific) will become less relevant. This is because within such an advanced and benevolent society, each individual’s potential can be fully realized, representing the total creative power available in the universe. Upon reaching this potential, there is no need for anything more from outer space, especially once our scientists, driven by business interests, learn to tap into the universal interstellar computer.

The answer, therefore, to the outer-space UFO question reduces to:

1. It’s likely that numerous highly developed civilizations across the universe possess the ability to reach out to, and even visit Earth.
2. However, there has never been any credible scientific proof demonstrating that any communication or encounters with extraterrestrial intelligence have taken place on our planet.
3. It’s logical to assume that these advanced civilizations, equipped with the technology needed to contact Earth, would lack any economic, social, or scientific motivation to do so. This is because once such a civilization has thoroughly explored, understood, and utilized a certain area of space, the urge and incentive to continue probing further and deeper into space, incurring greater costs, would gradually vanish.

[1] “Scientific” mysticism often stems from the desire to find external forces or “authorities” that can relieve the human mind from the task of thinking. Mystics yearn for an effortless guide to knowledge and life, steered by forces beyond their control. However, such an effortless guide does not exist. No external force can replace the work of an individual’s mind. Instances such as the U.S. president relying on astrology or the U.S.S.R. government funding research into ESP, psychokinesis, PK, and other pseudosciences, highlight the intellectual inadequacy of these governments and their leaders. In truth, these governments appear foolish and their leaders are merely jesters. They are gradually becoming obsolete due to the global exposure of their many incompetencies.

[2] Ironically, unilateral peace and disarmament movements, often championed by professional mystics and looters, are not just dishonest and mystical, but they also push the world towards nuclear annihilation. On the other hand, a well-prepared and rational society can not only effectively guard against nuclear war but also thrive in the future. This is because self-protection is a fundamental moral duty. Therefore, developing an efficient Strategic Defense Initiative (SDI) or “Star-Wars” defense system is the most logical and ethical action any country could take to safeguard its citizens and their property. (Refer to No-Pill Advantage #110 for an in-depth discussion on the inherent right to self-defense.)

[3] The only plausible reason for a highly advanced civilization to communicate beyond their immediate star system might be the imminent death of their sun, their primary energy source, through a cataclysmic event or eventuality. Such a civilization would likely seek to explore and colonize planets in nearby star systems. Given the ever-shifting positions of stars within our Milky Way galaxy, Earth could, at certain instances, become a “nearby” star system (for instance, less than a hundred light years away) to a civilization needing to abandon their own solar system due to an impending solar detonation or other disaster. Under such circumstances, Earth could become a target for exploration or even colonization from space. However, statistically, the chance of such a convergence of events is extremely low.

{ https://freetheanimal.com/ }

16-06-2024 om 20:20 geschreven door peter  

Exploring the phenomena of precognitive dreams involves examining their definition, context within history, and intriguing theories about the nature of time as it relates to dreams.

Dreams May Predict the Future

A new study finds that while some neurons replay past events during sleep, others surprisingly anticipate future experiences, potentially explaining how dreams can sometimes predict the future.

Summary: A new study reveals that some neurons in the brain not only replay past events during sleep but also anticipate future experiences, which may explain how dreams can sometimes predict the future. This research, published in Nature, involved observing individual neurons in the hippocampus of rats during rest after navigating a maze. The study utilized a novel machine-learning approach to track the spatial tuning of neurons, discovering that while many neurons stabilize memories during sleep, others adapt to anticipate future experiences, highlighting significant neuroplasticity during sleep.

Key Takeaways:

• Predictive Dreams: The study found that some neurons in the brain not only replay past events during sleep but also anticipate future experiences, potentially explaining the phenomenon of predictive dreams.
• Neuroplasticity During Sleep: Researchers observed that neuroplasticity, the brain’s ability to form new neural connections, occurs during sleep as some neurons change their representations to anticipate future experiences.
• Innovative Methodology: The study employed a statistical machine-learning approach to track neuron activity during sleep, providing new insights into how the brain consolidates and anticipates experiences even in the absence of stimuli.

Some dreams may, in fact, predict the future: New research has found that during sleep, some neurons not only replay the recent past but also anticipate future experiences.

The discovery is one in a series of insights afforded by a study on sleep and learning published in Nature by a team of researchers from Rice University and the University of Michigan. The research offers a view of how individual neurons in the hippocampus of rats stabilize and tune spatial representations during periods of rest following the animals’ first time running a maze.

“Certain neurons fire in response to specific stimuli,” says Kamran Diba, PhD, an associate professor of anesthesiology at Michigan and corresponding author on the study, in a release. “Neurons in the visual cortex fire when presented with the appropriate visual stimulus. The neurons we’re studying show place preferences.”

Neuronal Activity During Sleep

Together with collaborators in Michigan’s Neural Circuits and Memory Lab led by Diba, Rice neuroscientist Caleb Kemere, PhD, has been studying the process by which these specialized neurons produce a representation of the world after a new experience. Specifically, the researchers tracked sharp wave ripples, a pattern of neuronal activation known to play a role in consolidating new memories and, more recently, also shown to tag which parts of a new experience are to be stored as memories.

“For the first time in this paper, we observed how these individual neurons stabilize spatial representations during rest periods,” says Kemere, associate professor of electrical and computer engineering and bioengineering at Rice, in a release.

Sleep is critical for memory and learning; science has quantified this age-old intuition by measuring performance on memory tests after a nap as opposed to after a period of waking or even sleep deprivation.

Insights from Previous Studies

A couple of decades ago, scientists also discovered that neurons in the brains of sleeping animals that had been allowed to explore a new setting just before resting were firing in ways that replayed the animals’ trajectories during exploration. 

This finding aligned with the knowledge that sleep helps new experiences crystallize into stable memories, thus suggesting that the spatial representations of many of these specialized neurons in the hippocampus are stable during sleep. However, the researchers wanted to see if there was more to the story.

“We imagined that some neurons might change their representations—reflecting the experience we’ve all had of waking up with a new understanding of a problem,” Kemere says in a release. “Showing this, however, required that we track how individual neurons achieve spatial tuning, ie, the process by which the brain learns to navigate a new route or environment.”

Tracking Neuronal Preferences

The researchers trained rats to run back and forth on a raised track with a liquid reward at either end and observed how individual neurons in the animals’ hippocampus would “spike” in the process. By calculating an average spiking rate over many laps back and forth, the researchers were able to estimate the neurons’ place field—or the area in the environment that a given neuron “cared” about most.

“The critical point here is that place fields are estimated using the behavior of the animal,” Kemere says in a release, highlighting the challenge of assessing what happens to place fields during rest periods when the animal is not physically moving through the maze.

“I’ve been thinking for a long time about how we can evaluate the preferences of neurons outside of the maze, such as during sleep,” Diba says in a release. “We addressed this challenge by relating the activity of each individual neuron to the activity of all the other neurons.”

This was the study’s key innovation: The researchers developed a statistical machine-learning approach that used the other neurons surveyed to map out an estimate of where the animal was dreaming of being. They next used those dreamed positions to estimate the spatial tuning process for each neuron in their data sets.

New Findings

“The ability to track the preferences of neurons even without a stimulus was an important breakthrough for us,” Diba says in a release.

Both Diba and Kemere commended Kourosh Maboudi, a postdoctoral researcher at Michigan and the lead author on the study, for his role in the development of the learned tuning approach.

The method confirmed that the spatial representations that form during the experience of a new environment are, for most neurons, stable across several hours of postexperience sleep. But as the researchers had anticipated, there was more to the story.

“The thing that I loved the most about this research and the reason that I was so excited about it is finding that it’s not necessarily the case that during sleep the only thing these neurons do is to stabilize a memory of the experience,” Kemere says in a release. “It turns out some neurons end up doing something else. 

“We can see these other changes occurring during sleep, and when we put the animals back in the environment a second time, we can validate that these changes really do reflect something that was learned while the animals were asleep. It’s as if the second exposure to the space actually happens while the animal is sleeping.”

Neuroplasticity Observed

This is significant because it constitutes direct observation of neuroplasticity as it is happening during sleep. Kemere underscored that almost all plasticity research, which examines the mechanisms that allow neurons to rewire and form new representations—looks at what happens during waking periods as stimuli are being presented rather than during sleep when the relevant stimuli are absent.

“It seems like plasticity or rewiring in the brain requires really fast timescales,” Diba says in a release, pointing to the fascinating relationship between the duration of actual experience, “which can take up the span of seconds, minutes but also hours or days,” and actual memories, “which are super compressed.”

“If you remember anything, the memory, it’s instant,” Diba says in a release, referencing a famous literary passage by French modernist writer Marcel Proust in which a childhood memory unspools a whole lost world of past experience at barely a moment’s notice.

Future of Brain Science

The study is an example of advancements in neuroscience enabled in the past few decades by technological progress in the design of stable, high-resolution neural probes as well as by machine learning-backed computation power.

In light of these advancements, Kemere says brain science stands poised to make significant progress in the future, while at the same time expressing concern for the impact of recent budget cuts on continued research.

“It’s quite possible that if we were starting this work today, we might not have been able to do these experiments and get these results,” Kemere says in a release. “We’re definitely grateful that the opportunity was there.”

• Photo 2993492 © Richard Griffin | Dreamstime.com

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13-06-2024 om 22:44 geschreven door peter