Tag Archives: universe

Astronomers produce the most extensive map of quasars in the universe ever recorded

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of new mapThis quasar, called Quaia, contains about 1,295,502 quasars from across the visible universe and could help astronomers better understand the properties of dark matter.

story fisher other. This is an all-sky quasar catalog that samples the largest comoving volume of any existing spectroscopic quasar sample.Image credit: Story Fisher other., doi: 10.3847/1538-4357/ad1328.

Quasars are powered by supermassive black holes at the centers of galaxies and can be hundreds of times brighter than entire galaxies.

When the black hole's gravity kicks up nearby gas, the process creates a very bright disk, and sometimes a jet of light, that can be observed with telescopes.

The galaxies that quasars live in are hidden in huge clouds of invisible dark matter.

The distribution of dark matter gives insight into how much dark matter is present in the universe and how strongly clustered it is.

Astronomers compare these measurements across cosmic time to test current models about the composition and evolution of the universe.

Quasars are so bright that astronomers use them to map dark matter in the distant universe and fill in a timeline of how the universe evolved.

For example, scientists are already comparing the new quasar map to the Cosmic Microwave Background, the oldest snapshot of light in the universe.

As this light travels to us, it is bent by an intervening web of dark matter (the same web drawn by quasars), and by comparing the two, scientists can determine how matter changes over time. You can measure how strongly it clumps together.

“The new quasar catalog differs from all previous catalogs in that it provides the largest volumetric three-dimensional map in the history of the universe,” said David, an astronomer at the Center for Computational Astrophysics at the Flatiron Institute in New York.・Professor Hogg said. University.

“This is not the catalog with the most quasars or the highest quality quasar measurements, but it is the catalog with the largest total volume of the universe mapped.”

Professor Hogg and his colleagues constructed the Quasar map using data from the third data release of ESA's Gaia mission, which includes 6.6 million quasar candidates, as well as data from NASA's Wide-field Infrared Explorer and Sloan Digital Sky Survey. did.

By combining the datasets, contaminants such as stars and galaxies were removed from Gaia's original dataset and the distance to the quasar was determined more precisely.

“We were able to measure how matter clustered in the early universe with as much precision as those from major international research projects. Data as a 'bonus' from the Milky Way This is quite remarkable considering that we got . We are focusing on the Gaia project,” said Dr. Kate Storey-Fisher, a postdoctoral researcher at the International Physics Center Donostia.

“It's very exciting to see this catalog spurring so much new science.”

“Researchers around the world use quasar maps to measure everything from variations in the initial density that seeds the cosmic web, to the distribution of voids in the universe, to the movement of our solar system through space. ”

Astronomers have created a map showing where dust, stars, and other nuisances are expected to obstruct the view of certain quasars. This is important in interpreting quasar maps.

“This catalog of quasars is a great example of how productive astronomy projects can be,” Professor Hogg said.

“Gaia was designed to measure stars in our galaxy, but it also discovered millions of quasars, giving us a map of the entire universe.”

of result will appear in astrophysical journal.

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Kate Story Fisher other. 2024. Quair, Gaia-unWISE quasar catalog: all-sky spectroscopic quasar samples. APJ 964, 69; doi: 10.3847/1538-4357/ad1328

Source: www.sci.news

Stephen Hawking’s closest collaborator explains his final theory: The Universe as a hologram

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In 1998, Stephen Hawking accepted me as a doctoral student to “work on the quantum theory of the Big Bang.” This PhD project turned into a close collaboration that lasted almost 20 years, ending with his passing on March 14, 2018, five years ago. .

Our research focused on the mystery of how the Big Bang created conditions conducive to life. The intention behind this mysterious occurrence puzzled us.

These questions pushed the boundaries of physics, a realm Hawking enjoyed exploring. He was motivated by the possibility of unraveling the mysteries surrounding the universe’s design.

Our joint scientific endeavors brought us closer as collaborators. His determination and optimism towards solving cosmic mysteries were inspiring and influential.

He made us feel like we were crafting our own creation narrative, a shared journey we embarked on.

The concept of time initiating with the Big Bang was initially proposed by Georges Lemaître, which Einstein initially dismissed. Eventually, Hawking and Roger Penrose validated Lemaître’s theory.

The inception of time has remained a fundamental aspect of Big Bang cosmology, posing questions about its existence.

Hawking’s final theory on the Big Bang proposes a unique and bold perspective: the universe as a holographic projection.

His visualization of this idea involved a disc-shaped image, resembling the one depicted above. The holographic past cannot extend beyond the Big Bang.

Our theory points to the Big Bang as the origin of time, shedding light on the universe’s design mystery from a different angle.

Dr. Thomas Hertog, a Belgian cosmologist at the University of Leuven, is the author of the upcoming book “About ‘The Origin of Time’: Stephen Hawking’s final episode theory,” releasing on April 4, 2023. You can pre-order it at Penguin and Amazon UK.

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Source: www.sciencefocus.com

A Possible Discovery of a Parallel Universe with Time Reversed Travel

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Things happen at a glacial pace in Antarctica. Just ask Peter Gorham. For a month at a time, he and his colleagues float a giant balloon loaded with a collection of antennas above the ice, traversing more than a million square kilometers of frozen terrain in search of evidence of high-energy particles arriving from space. I watched it scan.

When the experimental aircraft returned to the ground after its first flight, it showed nothing of itself, except for the odd flash of ambient noise. The same situation occurred after the second flight over a year later.

During the balloon's third flight, the researchers decided to revisit past data, especially signals that had been ignored as noise. It was lucky that they did. Upon closer inspection, one signal appeared to be a signature of a high-energy particle. But that wasn't what they were looking for. Plus, it seemed impossible. These particles did not fall from above, but were ejected from the ground in an explosive manner.

This strange discovery was made in 2016. Since then, all kinds of proposals rooted in known physics have been put forward to explain this complex signal, but all have been ruled out. What is left behind is shocking in its implications. To explain this signal, we need the existence of a dizzying universe that was created in the same Big Bang as ours and exists in parallel. In this mirror world, plus is minus, left is right, and time goes backwards. This is probably the most heart-melting idea ever to come out of Antarctic ice, and it just might be true.

My ambition is…

Source: www.newscientist.com

Can consciousness exist in the universe? It may seem impossible, but the math tells a different story.

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They call it “the irrational validity of mathematics.” Physicist Eugene Wigner has the fascinating ability to describe and predict all kinds of natural phenomena, from the movements of planets and the strange behavior of fundamental particles to the effects of the universe, simply by manipulating numbers. He coined the term in the 1960s to summarize the facts. A collision between two black holes billions of light years away. Some are now wondering whether mathematics succeeds where all else fails, figuring out what it is that allows us to ponder the laws of nature in the first place.

That’s a big question. The question of how matter creates felt experiences is one of the most vexing problems we know of. And sure enough, the first fleshed-out mathematical model of consciousness sparked a huge debate about whether it could tell us anything meaningful. But as mathematicians strive to hone and expand the tools for looking deep within themselves, they are faced with some surprising conclusions.

In particular, they make clear that if we are to achieve an accurate account of consciousness, we must abandon our intuitions and realize that all kinds of inanimate objects, perhaps the entire universe, can be conscious. It seems to suggest that we may need to accept it. “This could be the beginning of a scientific revolution,” he says. Johannes KleinerMathematician at the Munich Center for Mathematics and Philosophy in Germany.

If so, it’s been going on for a long time. Philosophers have wondered about the nature of consciousness for thousands of years, but to little avail. Then half a century ago, biologists got involved. they discovered…

Article amended on May 4, 2020Fix: The campus of the Norwegian Inland University of Applied Sciences, where Hedda Hassel-Morch is based, has been updated to change the attribution of research on the effects of sleep or sedation on Phi.

Source: www.newscientist.com

New Study Suggests Photons from Dwarf Galaxies Helped Reionize the Early Universe

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Reionization of the universe happened about 500 million to 900 million years after the Big Bang. This represents the transformation of neutral hydrogen into an ionized gas and marks the end of the “Dark Ages” in the history of the universe. Currently, astronomers using the NASA/ESA/CSA James Webb Space Telescope have obtained spectra of eight ultrafaint dwarf galaxies that existed less than a billion years after the Big Bang. Their observations could help settle long-standing scientific debates about the driving force of reionization and could also be essential to understanding the formation of the first galaxies.

Astronomers estimate that 50,000 near-infrared sources are represented in the Webb image of galaxy cluster Abel 2744. Image credits: NASA / ESA / CSA / I. Labbe, Swinburne Institute of Technology / R. Bezanson, University of Pittsburgh / A. Pagan, STScI.

There is still much we don’t understand about the period in the early history of the universe known as the Era of Reionization.

It was a time of darkness, without stars or galaxies, and filled with a thick fog of hydrogen gas, until the first stars ionized the surrounding gas and light began to pass through.

Astronomers have spent decades trying to identify sources that emit radiation powerful enough to gradually remove this hydrogen fog that blanketed the early universe.

“Our discovery reveals the important role played by ultrafaint galaxies in the evolution of the early universe,” said astronomer Dr. Irina Chemelinska from the Paris Institute of Astrophysics.

“They produce ionizing photons that convert neutral hydrogen into ionized plasma during the reionization of the universe.”

“This highlights the importance of understanding low-mass galaxies in shaping the history of the universe.”

“These cosmic power plants collectively emit more than enough energy to accomplish their work,” said Dr. Hakim Atek, also of the Paris Institute of Astrophysics.

“Despite their small size, these low-mass galaxies produce large amounts of energetic radiation, and their abundance during this period is so great that their collective impact alters the state of the entire universe can do.”

In the study, astronomers captured and analyzed the spectra of eight very faint galaxies magnified by the lensing star cluster Abel 2744.

They found that these galaxies emit large amounts of ultraviolet light, at levels four times higher than previously thought.

This means that most of the photons that reionized the Universe likely came from these dwarf galaxies.

“With the web, we have stepped into uncharted territory,” said Dr. Themiya Nanayakkara, an astronomer at Swinburne University of Technology.

“Our study reveals more provocative questions that must be answered in efforts to chart the evolutionary history of our beginnings.”

of result It was published in the magazine Nature.

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H. Atek other. 2024. Most of the photons that reionized the universe came from dwarf galaxies. Nature 626, 975-978; doi: 10.1038/s41586-024-07043-6

Source: www.sci.news

The Dark Universe: A Novel

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science of phenomena

Being optimistic, believing in your abilities, practicing affirmations, being grateful, and setting clear goals can bring real benefits. But is manifestation pure pseudoscience, or does it mean something? We look at how the WOOP approach can actively support you on your journey towards realizing your dreams. I’ll go.

volcanic eruption

After three years of violent eruptions, experts now believe that Iceland’s Reykjanes Peninsula has entered a new phase of volcanic activity.

counterintuitive universe

The world is not what it seems. This special feature explores how science has exposed fallacies and false beliefs about heaven and earth throughout history.

planet nine

Something strange is happening beyond Neptune, and it may change everything we think we know about our solar system. Could orbital oddities reveal the existence of undiscovered planets near our heavens? Or is it something else?

plus

  • CES 2024’s biggest innovations: Every year, Las Vegas hosts the Consumer Electronics Show, where technology manufacturers from around the world gather to unveil their latest developments. From transparent technology to domestic robots and the latest cooking appliances, technology expert Alex Hughes shares some of the highlights.
  • Pothole: There are 750,000 potholes in Britain’s roads, creating a crater-like structure. These can cause serious damage to vehicles and pose a danger to drivers, cyclists, and pedestrians. But with bacteria and self-healing asphalt, it could be smooth again.
  • First moon base: Head to the moon’s south pole to peer inside what may be the first human habitation on the moon. Initially he planned to house 144 people, but the modular design of the Lunar Habitat Master Plan will expand and evolve with the inhabitants.

Issue 402 Released on February 22, 2024

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don’t forget that BBC Science Focus Also available on all major digital platforms. There is a version of android, Kindle Fire and Kindle e-readers, but also, iOS app For iPad and iPhone.

Source: www.sciencefocus.com

The Complexity of the Human Brain: Is It Truly Unmatched in the Universe?

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Crescent Nebula: More complex than the human brain?

Reinhold Wittich/Stocktrek Images/Alamy

Back in 2012, neuroscientist Christoph Koch wrote in his book: Consciousness: Confessions of a Romantic Reductionist The human brain is “the most complex object in the known universe.” This seems intuitive, given that the brain has approximately 86 billion neurons, which are connected in ways that are still beginning to be understood. But when I put it, David Wolpert At New Mexico's Santa Fe Institute, founded in the 1980s as a hub for the budding field of complexity science, he doesn't think so. “It's almost a travesty that we are the most complex system in the universe,” he says. “That question is actually misguided.”

Nevertheless, I persevere. Is there a common measure of complexity that can be applied to complex systems of all kinds? After all, if you squint, galaxy clusters and the filaments that connect them look like intertwined circuits of neurons. Masu. The human brain even has almost as many neurons as there are galaxies in the observable universe. This formal similarity may have something to do with the general laws by which complexity emerges, he says. Ricard Sole At Pompeu Fabra University in Barcelona, ​​Spain. Or maybe not. “By chance, it might show up in both systems, but that doesn't mean anything,” he says.

Moreover, complexity is not defined by components and their interconnections. It's the idea that the whole is more than just something.

Source: www.newscientist.com

The Sun-Fueled Black Hole: Potential to Shine as the Brightest Object in the Universe

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CAPE CANAVERAL, Fla. — Researchers have identified a quasar with a black hole at its center that may be the most luminous object in the universe. This quasar is growing at an incredible rate, capable of consuming an amount equivalent to the sun in a single day.

The record-breaking quasar shines 500 trillion times brighter than the sun. Scientists reported in the journal Nature Astronomy that the black hole fueling this quasar is more than 17 billion times more massive than the sun.

Despite appearing as mere dots in images, scientists believe quasars to be formidable entities.

The disk of luminous gas and other material orbiting a quasar’s black hole is akin to a cosmic hurricane.

“This quasar is the most violent place in the universe as we know it,” said lead author Christian Wolff of the Australian National University.

The object, known as J0529-4351, was initially discovered by the European Southern Observatory in 1980 and misclassified as a star. It was not confirmed to be a quasar until last year, after telescope observations in Australia and the Atacama Desert in Chile.

“What’s interesting about this quasar is that it’s hiding in plain sight and was previously misclassified as a star,” said Priyamvada Natarajan of Yale University.

Further analysis revealed that the quasar consumes the equivalent of 370 suns a year, or one sun a day, and the black hole at its center has a mass between 17 billion and 19 billion times that of the sun. More observations are needed to understand its growth rate.

Quasars are located 12 billion light years away and have existed since the beginning of the universe. One light year is 5.8 trillion miles.

Source: www.nbcnews.com

CERN’s New 91km-Long Particle Accelerator May Soon Unveil the End of the Universe

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Officials at CERN, the world’s leading particle physics research institute, have announced plans to build the world’s largest particle accelerator. The machine is designed to smash molecules at near the speed of light, marking a significant step forward.

The proposed super collider, called the Future Circular Collider (FCC), will be a massive 91 km in length, three times the size of the Large Hadron Collider (LHC). This new machine will allow scientists to collide particles with greater precision and energy than ever before, potentially unraveling some of the universe’s biggest mysteries. These include the existence of more matter than antimatter, the nature of dark matter and energy, the presence of hidden extra dimensions, and the existence of the universe as a whole.

This step forward is significant because scientists hope the FCC will deepen their understanding of particle physics, aiming to explain why particles have specific masses and forces, and to uncover the nature of dark matter and dark energy, which account for 95% of the mass-energy of the universe. If approved, construction is expected to start by the mid-2030s, with the first stage operating around 2045, followed by a second phase extending research into the 2070s, establishing the FCC as a multigenerational scientific research effort.

Is bigger always better?

The importance of building larger particle accelerators lies in the fact that they can achieve higher collision energies. The goal is to put in enough energy to create new particles, such as the Higgs boson. The FCC aims to eventually reach seven times the collision energy of the LHC, offering a new and more complete understanding of physics.

The FCC will be capable of creating millions of Higgs particles, providing scientists with the opportunity to study them in great detail to understand how they interact with other particles. The Higgs boson is a carrier particle of the Higgs field that permeates space and gives mass to other particles, challenging previously held concepts about matter and mass.

CERN’s proposed super collider would be 91 km long and would be the largest particle collider ever built. The hope is that its increased precision and higher collision energies will eventually allow physicists to understand the nature of the Higgs boson, and perhaps even reality itself. – Image credit: CERN

god particle

In addition to providing deeper insight into the Higgs boson, the FCC will also aim to uncover the mechanisms by which the Higgs boson interacts and its significance in the universe. It is thought to have played a crucial role in the very beginning of the universe, nanoseconds after the big bang, by giving mass to matter as the universe grew and cooled. The influence of the Higgs boson is also relevant in understanding how the universe will end, as it affects the stability of the universe itself.

The FCC is expected to contribute to our understanding of whether the universe is in a stable or unstable state, providing the key to answering fundamental questions about the universe’s fate.

the beginning and end of the universe

The FCC will play a crucial role in answering questions about the beginning and the end of the universe, with the expertise of notable scientists like Marcus Chown, professor Andy Parker, and Matthew McCullough. The expectation is that this new accelerator will contribute to an in-depth understanding of the fundamental physics that govern the universe and our place within it.

About our experts

Marcus Chown is an award-winning author, broadcaster, and former radio astronomer. He is the author of Breakthrough: The Spectacle of Scientific Discovery His Story from the Higgs Boson to the Black Hole (Faber & Faber, 2021). Professor Andy Parker is a British physicist and professor of high-energy physics at the University of Cambridge. He is a member and chair of the CERN Science Policy Committee and the Scientific Advisory Committee on Future Circular Colliders, among other notable positions. Matthew McCullough is a theoretical physicist and researcher at CERN, focused on areas of interest including collisional physics, cosmology, astroparticle physics, and quantum field theory, involved in FCC feasibility studies.

Source: www.sciencefocus.com

10 of the Biggest Stars in the Universe

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The stars that exist in our universe are definitely huge. In fact, our closest star, the Sun, has a diameter of an astonishing 1.4 million km (865,000 miles), which is large enough to fit 1.3 million Earths within it.

However, within the grand scale of the universe, this is a fairly average size. Although many stars are small, scientists have discovered many cosmic giants that are hundreds of times larger. But what is the largest star in the universe?

Introducing the 10 biggest stars ever known to humanity.

10.HV888

HV 888 is circled in the center of the image. Photo courtesy of ESO/Digitalized Sky Survey 2

HV 888 looks a lot like Clifford the dog, except it is located 163,000 light-years away, and is red and very large.

With a solar radius of 1,374 (our Sun has a solar radius of 1), this scarlet supergiant’s color actually indicates that it is nearing the end of its life. Scientists don’t know exactly when the star will go supernova. It could be today, or the star could continue to burn for millions of more years.

Until then, HV 888 will shine incredibly brightly, about 300,000 to more than 500,000 times brighter than the Sun. In other words, anyone living on one of this star’s possible exoplanets would likely need some pretty bright sunglasses.

9. Ah, Scorpio

Star AH Scorpio. Photo courtesy of ESO/Digitalized Sky Survey 2

AH Scorpii is a red supergiant star found in the constellation Scorpius, hence its name. Although she is 1,411 times larger than the Sun, the star is probably much cooler, with a surface temperature between 3,176.85°C (5750.33°F) and 3,408.85°C (6167.93°F). For comparison, our sun is hot at 5,226.85°C (9380.33°F).In other words, AH Scorpio is still very very hot.

8.CM Velorum

Star CM Verorum. Photo courtesy of ESO/Digitalized Sky Survey 2

CM Bellorum, located in the constellation Vela, is a red star 1,416 times larger than the Sun. However, despite its size, this star is invisible to the naked eye without a telescope. This is partly due to its distance from Earth, which is calculated to be approximately 15,000 light-years away.

7.HD12463

Star HD 12463. Photo credit: ESO/Digitized Sky Survey 2

Not much is known about the star, known as HD 12463, but it is estimated to be 1,420 times larger than the Sun. It is located about 163,000 light-years from us in the Large Magellanic Cloud, a galaxy derived from the Milky Way.

6. VY Canis Major

Star VY Canis Major. Photo courtesy of ESO/Digitalized Sky Survey 2

VY Canis Majoris is an oxygen-rich supergiant star 1,420 times larger than the Sun. It is so large that even traveling at the speed of light, it would take him 6 hours to circumnavigate its surface (try this with the Sun and it would take only 14.5 seconds).

Even if you have the time, I don’t recommend it. The temperature of this star is 3,730°C (6,740°F). It’s also incredibly bright, about 300,000 to 500,000 times brighter than the Sun.

5.HD 269551

Star HD 269551 in the Large Magellanic Cloud. Photo courtesy of ESO/Digitalized Sky Survey 2

HD 269551 may not have the catchiest name in the universe, but it’s still a memorable star for its massive size. Its size has been measured to be 1,439 times that of the Sun.

Like many of the large stars on this list, HD 269551 is highly unstable and nearing the end of its life, and will explode as a supernova within the next few million years (a very short time in the grand scale of the universe) It is expected that

4.RSGC1-F01

Spitzer telescope image of the RSGC1 star cluster, home to RSGC1 F01 and many other massive stars. Photo by NASA/Spitzer Telescope

RSGC1 F01 is located in a star cluster in the Milky Way galaxy in the constellation Scuta. Its size is estimated to be 1,436 to 1,530 times that of the Sun.

Remarkably, if RSGC1-F02 were placed at the center of our solar system, the star’s surface (known as the photosphere) would reach Jupiter’s orbit.

3.WOH 5170

WOH S170 shot with DSS2. Photo courtesy of Eso/Digitalized Sky Survey 2

WOH S170, located in the constellation Leo, is a red star 1,461 times larger than the Sun. Wow, sure.

2.WOH G64

This image shows WOH G64 (circled) in the Large Magellanic Cloud, a satellite galaxy of our Milky Way. Photo courtesy of NASA

WOH G64 is a very large star, 1,540 times the size of the Sun.That’s also very likely very Dusty: Encased in a thick layer of tiny particles about 1 light-year in diameter.

WHO G64 is also a very cool star (literally), with a temperature of 3,100°C (or 5,600°F). Compare this to the surface temperature of the sun. The sun’s surface temperature is a fairly warm 5,226.85°C (9380.33°F).

1. UY spine

Photo courtesy of Eso/Digitalized Sky Survey 2

UY Scuti is the largest star ever observed in the universe. The red supergiant star is 1,708 times the width of the Sun and has a radius of 1.2 billion km (738 million miles). This star is located approximately 9,500 light-years from Earth in the constellation Scutum, near the center of the Milky Way.

Despite its massive size, UY Scutum’s temperature is actually 40 percent colder than the Sun’s 3092°C (1700°F). This is because the star has already used up most of its hydrogen fuel, which produces heat and light. This lower temperature means the star emits a reddish glow.

UY Scuti is also a surprisingly young star, probably only 10 to 20 million years old. It may sound like an exaggeration, but the age of our sun is estimated to be 4.6 billion years. But UY Scuti burns through its fuel so quickly that the star is likely at the end of its life and may only have a few million years left.

It is not clear what happens to UY Scuti at the end of its life cycle. It’s possible that the star could explode in a polar nova (triggering a shock wave that triggers the formation of new stars), but one theory suggests UY Scuti would collapse to form a hotter star.

Star Estimation size (radius)
HV888 956 million km (595 million miles)
Oh, Scorpio 983 million km (611 million miles)
CM Velorum 987 million km (613 million miles)
HD12463 987 million km (613 million miles)
VY Canis Major 987 million km (613 million miles)
HD 269551 1.01 billion kilometers (622 million miles)
RSGC1-F01 1.01 billion km (627 million miles)
WOH S170 1,019 million km (633 million miles)
WOH G64 1,072 million km (666 million miles)
UY spine 1.19 billion km (739 million miles)

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Source: www.sciencefocus.com

Interview with Jim Peebles: Renowned cosmologist discusses the search for deeper theories of the universe

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Jim Peebles is widely known as the architect of modern cosmology and its nice-guy chief executive.give half a share of 2019 Nobel Prize in Physics, the committee said he “took up the universe” and helped create the framework known as the Standard Model of Cosmology, which is now considered “the basis of modern understanding of the history of the universe.” Others described him as an “extraordinary physicist” and “extraordinarily thoughtful, polite and kind.”

Now the Albert Einstein Professor Emeritus of Science at Princeton University, Peebles' career began there in the 1960s, focusing on Einstein's theory of general relativity, in which gravity occurs as a result of distortions of mass in spacetime. . He later characterized the cosmic microwave background (CMB), an “echo” of the Big Bang, a discovery that made cosmology an experimental science. He also showed that halos of dark matter around galaxies create a mass distribution consistent with astronomers' observations, and that the description of our universe requires reinstatement of Einstein's much-derided cosmological constant. I convinced the field that there was. Initially incorporated into the equations of general relativity as an unwieldy trick, it is now thought of as dark energy, the repulsive force driving the accelerating expansion of the universe.

Despite the success of the standard cosmological model, Peebles has always sought to undermine it. In recent years, he has focused his musings on observing astronomical anomalies – strange galaxies and other interesting phenomena – that may expose flaws in our thinking.

he says new scientist On his vision for cosmology and why it's important to deviate from the mainstream…

Source: www.newscientist.com

Possible Widespread Presence of Diamond Rain in the Universe

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Diamond rain could fall on many exoplanets

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The sky of an icy planet in space may be full of diamonds. Compacted carbon compounds may turn into diamonds at less extreme temperatures than researchers thought would be necessary, which could make diamond rain a common phenomenon inside giant ice cubes. there is.

In the past, laboratory experiments have confused the conditions under which diamonds form inside ice giants like Uranus and Neptune. There are two types of experiments to investigate this: dynamic compression experiments, in which a carbon compound is subjected to a sudden impact, and static compression experiments, in which it is placed in a chamber and gradually compressed. Previous dynamic compression experiments required much higher temperatures and pressures to form diamonds.

mango frost Using static compression and dynamic heating, researchers at SLAC National Accelerator Laboratory in California sandwiched polystyrene (the same polymer used to make Styrofoam) between two diamonds and applied an X-pulse. We conducted a new series of experiments to compress Ray of light. They observed diamonds begin to form from polystyrene at temperatures of about 2,200 degrees Celsius and pressures of about 19 gigapascals, conditions similar to the shallow interiors of Uranus and Neptune.

These pressures are much lower than those found necessary for diamond formation in previous experiments using dynamic compression. This reaction took longer than the typically performed dynamic compaction experiments. This may explain why no low-pressure diamond formation was detected in such experiments. “It didn't match the established results and wasn't what we expected, but it was a good fit and brought everything together,” Frost says. “It turns out it's all due to different timescales.”

This could mean that diamonds could rain on smaller planets than previously thought. The researchers calculated that of the approximately 5,600 exoplanets identified, more than 1,900 could rain diamonds.

This also means that diamonds may form at shallower depths within our solar system than we think, which could change our understanding of the internal dynamics of giant planets. There is a possibility that it will change. This shallow geological formation could allow diamond rain to pass through layers of ice as it sinks toward the centers of these planets. This, in turn, will affect the icy world's magnetic fields, which are complex and poorly understood.

topic:

Source: www.newscientist.com

The Impact of Plasma Instability on Our Understanding of the Universe

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Scientists have discovered a new instability in plasma, revolutionizing our understanding of cosmic rays. This groundbreaking discovery reveals that cosmic rays generate electromagnetic waves within plasma and influence their paths. This collective behavior of cosmic rays, similar to waves formed by water molecules, challenges previous theories and holds promise for insights into intragalactic cosmic ray transport and its role in galaxy evolution. Credit: SciTechDaily.com

Scientists at the Potsdam Leibniz Institute for Astrophysics (AIP) have discovered a new substance. plasma This instability is expected to revolutionize our understanding of the origin of cosmic rays and their dynamic impact on galaxies.

At the beginning of the last century, Victor Hess discovered a new phenomenon called cosmic rays, for which he was later awarded the Nobel Prize. He conducted high-altitude balloon flights and discovered that the Earth’s atmosphere was not ionized by ground radiation. Instead, he confirmed that the origin of ionization was extraterrestrial. Later, it was discovered that cosmic “rays” are composed of charged particles that travel from space at speeds close to the speed of light. radiation. However, the name “cosmic rays” outlasted these discoveries.

Recent advances in cosmic ray research

In the new study, AIP scientist and lead author of the study, Dr. Mohammad Shalaby, and his collaborators performed numerical simulations to trace the trajectories of many cosmic ray particles, showing that these particles We studied how the plasma interacts with the surrounding plasma, which is made up of electrons and electrons. proton.

Simulation of cosmic rays flowing in the opposite direction to the background plasma and causing plasma instability. The distribution of background particles in response to streaming cosmic rays is shown in phase space spanned by the particle’s position (horizontal axis) and velocity (vertical axis). Color visualizes number density, and holes in phase space represent the highly dynamic nature of instabilities that break up ordered motion into random motion. Credit: Shalaby/AIP

When researchers studied cosmic rays flying from one side of the simulation to the other, they discovered a new phenomenon that excites electromagnetic waves in the background plasma. These waves exert a force on the cosmic rays, causing them to change their meandering paths.

Understanding cosmic rays as a collective phenomenon

Most importantly, this new phenomenon is best understood if we think of cosmic rays as supporting collective electromagnetic waves rather than acting as individual particles. When these waves interact with the background fundamental waves, they are strongly amplified and a transfer of energy occurs.

“This insight allows us to think of cosmic rays in this context as behaving more like radiation than individual particles, as Victor Hess originally believed,” said AIP Cosmology and High Energy Astrophysics. says Professor Christoph Pfrommer, head of the section. .

Momentum distribution of protons (dashed lines) and electrons (solid lines). The appearance of a high-energy electron tail in a slowly moving shock is shown. This is the result of interactions with electromagnetic waves caused by newly discovered plasma instabilities (red) that are absent from faster shocks (black). This shows the importance of understanding the physics of the acceleration process, since only high-energy electrons produce observable radio radiation. Credit: Shalaby/AIP

A good analogy for this behavior is that individual water molecules come together to form waves that break on the shore. “This progress was only made possible by taking into account smaller scales, which had been overlooked until now and called into question the use of effective fluid dynamics theory when studying plasma processes,” explains Dr. Mohammad Shalaby. To do.

Meaning and application

This newly discovered plasma instability has many applications, including the first study of how electrons from thermal interstellar plasma are accelerated to high energies in supernova remnants. It also includes an explanation.

“This newly discovered plasma instability represents a major advance in our understanding of acceleration processes and finally explains why these supernova remnants glow in radio waves and gamma rays.” Mohammad Shalaby reports.

Moreover, this breakthrough opens the door to a deeper understanding of the fundamental processes of cosmic ray transport in galaxies. This represents the biggest mystery in understanding the processes that form galaxies during the evolution of the universe.

References:

“Deciphering the physical basis of mesoscale instability” by Mohammad Shalaby, Timon Thomas, Christoph Pfrommer, Reuven Lemmerz, and Virginia Bresci, December 12, 2023, Plasma Physics Journal.
DOI: 10.1017/S0022377823001289

“Mechanism of efficient electron acceleration in parallel non-relativistic shocks” by Mohammad Shalaby, Reuven Lemmerz, Timon Thomas, and Christoph Pfromer, May 4, 2022, Astrophysics > High-energy astrophysical phenomena.
arXiv:2202.05288

“New Cosmic Ray Instabilities” by Mohammad Shalaby, Timon Thomas, and Christoph Pfrommer, February 24, 2021, of astrophysical journal.
DOI: 10.3847/1538-4357/abd02d

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NASA’s Webb and Hubble team up to capture the most vivid image of the universe

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This panchromatic view of galaxy cluster MACS0416 was created by combining infrared observations from NASA’s James Webb Space Telescope with visible-light data from NASA’s Hubble Space Telescope. Credits: NASA, ESA, CSA, STScI, Jose M. Diego (IFCA), Jordan CJ D’Silva (UWA), Anton M. Koekemoer (STScI), Jake Summers (ASU), Rogier Windhorst (ASU), Haojing Yan ( University of Missouri)https://chat.openai.com/c/de5c3def-7d31-49b0-bd44-3d61675a3ae5

The result is a vivid landscape of the galaxy and more than a dozen newly discovered time-changing objects.

When the two flagship observatories come together, they reveal a wealth of new details that are only possible through their combined power. Webb and Hubble collaborated on studying MACS0416, a galaxy cluster about 4.3 billion light-years from Earth. Combining these data yields a prismatic panorama of blue and red. These colors provide clues to the galaxy’s distance. While the images themselves are surprising, researchers are already using these observations to fuel new scientific discoveries, such as identifying gravitationally expanded supernovae and ordinary stars.

This side-by-side comparison of galaxy cluster MACS0416 seen in optical light from the Hubble Space Telescope (left) and infrared light from the James Webb Space Telescope (right) reveals different details. Both images show hundreds of galaxies, but the Webb image shows galaxies that are invisible or only barely visible in the Hubble image. This is because Webb’s infrared vision can detect galaxies that are too far away or covered in dust to be seen by Hubble. (Light from distant galaxies is redshifted due to the expansion of the universe.) Webb’s total exposure time was about 22 hours, while the exposure time of the Hubble image was his 122 hours. Credit: NASA, ESA, CSA, STScI

NASA’s Webb Space Telescope and Hubble Space Telescope combine to create the most colorful view of the universe. NASA’s james webb space telescope and hubble space telescope They teamed up to study a vast galaxy cluster known as MACS0416. The resulting panchromatic images combine visible and infrared light to assemble one of the most comprehensive views of the universe ever captured. MACS0416, located approximately 4.3 billion light-years from Earth, is a pair of colliding galaxy clusters that will eventually merge to form an even larger cluster. Details revealed by the combination of stretching and contraction forces

This image reveals a wealth of detail only possible by combining the power of both space telescopes. This includes an abundance of galaxies outside the cluster and a scattering of light sources that change over time, possibly due to gravitational lensing (distortion and amplification of light from distant background sources). It is.

The galaxy cluster was the first in a series of unprecedented cosmic views into ultra-deep space from an ambitious joint Hubble program called Frontier Fields, launched in 2014. Hubble pioneered the search for some of the faintest and youngest galaxies ever detected. Webb’s infrared vision greatly enhances this deep observation by going even deeper into the early universe with its infrared vision.

This image of galaxy cluster MACS0416 highlights gravitational lensing background galaxies that existed about 3 billion years after the Big Bang. The galaxy contains an ephemeral object that the scientific team has named Mothra, whose brightness changes over time. Mothra is a star that is magnified at least 4,000 times. The researchers believe that Mothra is magnified not only by the gravity of the galaxy cluster MACS 0416, but also by an object known as a millilens, which weighs about the same as the globular cluster. Credits: NASA, ESA, CSA, STScI, Jose M. Diego (IFCA), Jordan CJ D’Silva (UWA), Anton M. Koekemoer (STScI), Jake Summers (ASU), Rogier Windhorst (ASU), Haojing Yan ( University of Missouri)

Roger Windhorst of Arizona State University, principal investigator of the PEARLS program (Extragalactic Field for Reionization and Lensing Science), which carried out the Webb observations, said: “We are looking at objects that are farther away and fainter. “By doing so, we are building on Hubble’s legacy.”Understand image color and scientific goals

To create the images, the shortest wavelengths of light were generally color-coded as blue, the longest wavelengths as red, and the intermediate wavelengths as green. The wide range of wavelengths from 0.4 to 5 microns provides particularly vivid galactic landscapes.

These colors provide clues to the galaxy’s distance. The bluest galaxies, as most commonly detected by Hubble, are relatively nearby and often exhibit intense star formation, while the redder galaxies, as detected by Webb, tend to be more distant. Some galaxies appear very red because they contain large amounts of cosmic dust that tends to absorb bluer-colored starlight.

“Until we combine the Webb data with the Hubble data, we won’t get the full picture,” Windhorst said.Scientific discoveries and the “Christmas Tree Galaxy Cluster”

New Webb observations contribute to this aesthetic view, but they were taken for a specific scientific purpose. The research team combined his three epochs, each conducted a few weeks apart, with his fourth epoch by the CANUCS (Canadian NIRISS Unbiased Cluster Survey) research team. The goal was to search for objects that change in brightness observed over time, known as transients.

They identified 14 such transients across the visual field. Twelve of these transients are located in three galaxies that are highly magnified by gravitational lensing, and may be individual stars or star systems that are temporarily highly magnified. The remaining two transients are in more moderately expanded background galaxies and may be supernovae.

“We call MACS 0416 the Christmas Tree Galaxy Cluster, both because it is so colorful and because of the flashing lights found within it. Transients are seen everywhere. ” said Haojing Yang of the University of Missouri-Columbia, lead author of a paper describing the scientific results.

Among the transients the team identified, one in particular stood out. It is located in a galaxy that existed about 3 billion years after the Big Bang and has been magnified by at least 4,000 times. The research team nicknamed the system “Mothra” for its “monstrous nature” of being extremely bright and highly magnified. It joins another lensed star that researchers previously identified and named “Godzilla.” (Godzilla and Mothra are both giant monsters known as kaiju in Japanese movies.)

Interestingly, Mothra can also be seen in Hubble observations taken nine years ago. This is unusual because zooming in on stars this much requires a very specific alignment between the foreground galaxy cluster and the background stars. The mutual motion of stars and star clusters should eventually dissolve the alignment.

Credits: NASA, ESA, CSA, STScI, Jose M. Diego (IFCA), Jordan CJ D’Silva (UWA), Anton M. Koekemoer (STScI), Jake Summers (ASU), Rogier Windhorst (ASU), Haojing Yan ( University of Missouri)”

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