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Q: Is it true that a black hole isn't a hole at all?

Watch a TV show on this fact.

1 year 10 weeks ago in  Teaching & Learning - Other cities

 
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I heard a blackhole was detected by a drunk foreign junkie in a sleazy bar carpark somewhere in Shanghai.

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Did you know ''1 billion ..." is 1000 millions ... by using short scale? There are two scales ... 

https://en.wikipedia.org/wiki/Billion

 

 Next, ... we must count the distance of three (3) billion light years ...

'One light year' is the distance light travels through the universe ... Light travels fast-er measured by Earth's measures ..

 

"Light travels at a speed of 299.792 km per second; 186,287 miles per second ...", so one light year would come exactly to :

 

"365 days X 24 hours X 60 minutes X 60 seconds" ... equals to

 

"31,536,000 seconds, i.e. one year seconds X 299,792 km =

  "9,354,240,512 km" .. or in other English words, light travels more than 9 billion km in one light year ... 

 

Now, c&p ...

Please pay attention, so you won't confuse different numbers:

 

"million' & 'billion' & 'brazillion"

 

Unexplained fast radio burst just ‘woke up’ exactly as scientists predicted

Unexplained fast radio burst just ‘woke up’ exactly as scientists predicted

Aug 24, 2020 10:35

 

Astronomers researching the mysterious Fast Radio Burst (FRB) 121102 have confirmed that the powerful phenomenon has a predictable cycle, which may allow us to find out what exactly is causing it once and for all.

First discovered in 2012, the FRB is located in a dwarf galaxy ... 3 billion light-years ... away making it very difficult to monitor, requiring some of Earth’s most powerful instruments. 

FRBs are intense blasts of radio waves which can release as much power as hundreds of millions of suns in mere milliseconds, but the majority of them that we have observed have flared once only to disappear, never to be heard from again. 

This makes it extremely difficult to discover their composition, monitor their behavior and determine their source. In other words, they are extraordinarily difficult to study let alone predict as scientists have just managed. 

A team led by Marilyn Cruces of the Max Planck Institute for Radio Astronomy, in conjunction with other research carried out at the University of Manchester by astronomer Kaustubh Rajwade, has unveiled their model for the FRB’s cycle.

For 67 days, FRB 121102 goes dark, not making any noise and effectively disappearing only to ‘wake up’ again for 90 days, producing these breathtaking millisecond radio flares that are so powerful we can see them billions of light-years away here on Earth. 

According to Cruces’ prediction for the FRB’s repeating and predictable 157-day cycle, it’s current flaring phase will last from July 9 and October 14, 2020 before it hibernates once more. 

Multiple international teams, including the National Astronomy Observatory of China which uses the Five-hundred-meter Aperture Spherical radio Telescope (FAST), will continue to monitor FRB 121102 to try and figure out what's behind these bursts. 

Now researchers all over the world have a specific timeframe in which to gather data before having a predetermined period for intense study without worrying they might miss some key detail or event. 

Just a tiny few FRBs have been detected repeating and they will likely hold the key to unravelling the mystery once and for all and allow us to determine what's really behind these phenomenally powerful blasts. The leading theory suggests that a certain kind of neutron star called a magnetar is responsible, but the mystery remains for the time being at least.

 

It says on the bottom:

 Think your friends would be  interested? Share this story! 

 

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Since, your knowledge of blaack hol-ines is mucho wider, I feel content of releasing my latest 'discovery' ... 

 

https://www.rt.com/news/501196-primordial-black-holes-dark-matter-mystery/

 

Monstrous black holes, the size of 100 billion suns, could help shed light on dark matter mystery

 

A new study has suggested that “stupendously large” black holes may exist, which harbor the mass of 100 billion suns. The discovery of such an enormous region of spacetime could shed light on the mystery of dark matter.

In the center of most galaxies, there are supermassive black holes with masses that are millions to billions of times that of Earth’s sun. In the heart of our own Milky Way lies Sagittarius A*, which weighs in at about 4.5 million solar masses. The largest black hole ever discovered is TON 618 and it has an incredible mass of 66 billion solar masses. 

But what if even bigger black holes are out there? A new study has posited the possible existence of “stupendously large black holes,” or SLABs, which could be the size of 100 billion suns, or bigger.

One burning question about SLABs is how would such a staggeringly enormous region of spacetime ever form? The theory of multiple black holes merging has already been discounted by previous research as they could not have reached supermassive size because the universe simply isn’t old enough.

However, one possible explanation is that the black holes could have primordial origins, dating back to the aftermath of the Big Bang that created the universe. The theory proposes that random fluctuations in density could have pooled enough matter to collapse into black holes, which then served as “seeds” for gigantic SLABs. 

The researchers say that the possibility of such massive black holes existing has been the focus of surprisingly little research despite the fact that they could exist in principle and they could help unravel some of the questions about dark matter that have dogged physics for decades.

Dark matter is believed to account for around 80 percent of the matter in the universe, but it has yet to be detected directly. Finding it would finally solve one of science’s most head-scratching mysteries, but for now researchers have had to rely only on studying its gravitational effects on normal matter.

“Some people may be skeptical about the existence of SLABs on the grounds that they would be hard to form,” study co-author Bernard Carr, a theoretical cosmologist at Queen Mary University of London, explained to Space.com.

“However, people were also skeptical about intermediate-mass and supermassive black holes until they were found. We do not know if SLABs exist, but we hope our paper will motivate discussion among the community.”

 

... you slabs ...

 

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‘No earthly fireworks display can compete’: Hubble beams back unreal footage of supernova explosion 70mn light years away

NASA's Hubble Space Telescope has captured the spectacular death of a star 70 million light-years away in incredible detail, which will help measure the elusive expansion rate of the universe.

Oct 2, 2020 08:50

NASA's Hubble Space Telescope has captured the spectacular death of a star 70 million light-years away in incredible detail, which will help measure the elusive expansion rate of the universe.

Hubble began observing the star, designated SN 2018gv, in February 2018, after an incredibly bright explosion was spotted in the area in January. In fact, the explosion was so bright it actually released as much as energy in a matter of days as our star does in a few billion years.

“No earthly fireworks display can compete with this supernova, captured in its fading glory by the Hubble Space Telescope," said Nobel laureate Adam Riess, of the Space Telescope Science Institute (STScI) and Johns Hopkins University in Baltimore.

Hubble took snapshots of the spectacular scene, which have been painstakingly turned into a video.

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ARSE - Australia Research and Space Exploration

https://spaceaustralia.com.au/

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Nobel Prize awarded to trio of BLACK HOLE scientists who discovered supermassive object and proved Einstein right

Nobel Prize awarded to trio of BLACK HOLE scientists who discovered supermassive object and proved Einstein right

A trio of scientists have been awarded the 2020 Nobel Prize for Physics for their discoveries which deepened humanity's understanding of black holes.

Oct 6, 2020 10:39 

Roger Penrose, Reinhard Genzel and Andrea Ghez were unveiled as the newest Nobel winners on Tuesday. “The discoveries of this year's Laureates have broken new ground in the study of compact and supermassive objects,” said David Haviland, chair of the Nobel Committee for Physics.

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https://theconversation.com/nobel-prize-how-penrose-genzel-and-ghez-help...

 

Nobel prize: how Penrose, Genzel and Ghez helped put black holes at the centre of modern astrophysics

 

The award of this year’s Nobel prize in physics to Roger Penrose, Reinhard Genzel and Andrea Ghez will be greeted with enormous pleasure by physicists and astronomers worldwide. It recognises the central importance of black holes in modern astrophysics, and the unique contributions of these three scientists in establishing this.

The physics that describes black holes comes from Einstein’s general theory of relativity (usually abbreviated to GR). GR is a little over a century old, and was from the start seen as a theory of unprecedented mathematical complication.

After some early successes, such as the observation that the paths of starlight bent under gravity as they passed near the Sun, the huge algebraic complexity of GR rapidly made it a backwater of physics. Laboriously derived solutions of Einstein’s equations found no practical application for experiments to test the theory.

Although one of these solutions hinted at properties we now know were characteristic of black holes, these were not understood at the time. And, in any case, they were often dismissed as artificial products of assumptions made for mathematical convenience. There seemed little hope of experimental tests that would reveal large and fundamentally new effects of GR.

Penrose is the theoretical physicist who made the crucial discovery that began the resurrection of GR theory from this apparent impasse to its dynamic state today, where its predictions – particularly about black holes – are constantly tested and verified.

Genzel and Ghez are the two astronomers whose observing teams independently verified the most extravagant prediction of GR by showing that our own galaxy, the Milky Way, has at its heart an enormously massive black hole described in intricate detail by the theory.

Roger Penrose, Andrea Ghez and Reinhard Genzel.

 

Penrose’s fundamental insight was that GR specifies physical causality: no physical effect can travel faster than light, and gravity bends light and determines how it moves. And in particular, gravity always attracts and never repels. In 1965, he showed that these properties alone make the objects we now call black holes an inescapable consequence of GR.

A crucial feature of this fundamental result is that it does not assume any geometrical symmetries in the matter that will eventually collapse under its own gravity to form a black hole. It need not be perfectly spherical, for example. Any misshapen collection of matter will end as a black hole if it has passed what Penrose identified as its point of no return, as it first traps light around itself.

In later years, he recalled implicitly recognising this crucial point while crossing a London street in the company of the engaging fellow physicist Ivor Robinson, and being so taken by their conversation that he could not at first recall just what had made him feel so happy on crossing the street.

I can well remember the shock of realising how utterly new this approach was as a young PhD student of GR a few years later. It bypassed the complexity of solving the GR equations, and its completely general methods forced astrophysicists to take seriously the idea of black holes as potentially observable objects.

We now know, for example, of many stellar binary systems where one of the stars has collapsed to form a black hole, a discovery that led to a share of the 2002 Nobel Prize for Riccardo Giacconi.

Supermassive discovery

Genzel and Ghez lead research groups that have independently shown that there is a much more massive black hole at the centre of the Milky Way. They did this by observing the motions of stars around this invisible object.

Years of painstaking observation by both groups reveal a rich pattern of about 40 stars orbiting with different periods, eccentricities and inclinations on the sky. Each of these orbits tells us the mass of the object whose gravity pulls on them, and all of them agree on a single huge value about 4 million times that of the Sun. But evidence from radio waves emitted near the object indicates that it is remarkably small, strongly suggesting that it must be a black hole.

Recent observations reveal that the orbits of the closest stars to the galactic centre are not quite perfect ellipses, but slowly move to trace out rosettes on the sky. This is precisely what GR predicts for very close orbits around a black hole. The independent but almost identical results of the two groups leave very little room for doubt that this is our own local supermassive black hole.

The consequences are profound, and I am just one of many astrophysicists studying them. Observations strongly suggest that the centre of almost every galaxy has its own supermassive black hole – many of them far more massive than in the Milky Way – and that these masses are closely related to detailed properties of the host galaxies. These supermassive black holes evidently play a major role in making galaxies as they are, creating the architecture of the universe we live in.

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  Through my constant vigilance ..   .. and some good fortune cookies, butT .. you knew that ...

 

Astronomers capture exact moment supermassive black hole DEVOURED entire star

Through constant vigilance and some good fortune, astronomers have managed to capture the moment a supermassive black hole in a galaxy 215 million light-years away tore a star apart.   

The so-called ‘tidal disruption event’ (TDE) is the closest such death of a star humanity has ever witnessed.

Astronomers were alerted by the intense flash of light, visible hundreds of millions of light years away, just before parts of the star disappeared into the black hole’s event horizon after being ‘spaghettified’ by the immense gravity.

... more with short vid ...

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 Have you ever had a thorn? ... like me ... 

 

Astronomers solve riddle of ‘impossible’ galaxy made of 99.99% dark matter

Astronomers solve riddle of ‘impossible’ galaxy made of 99.99% dark matter

The Dragonfly 44 galaxy has been a thorn in the scientific community’s side ever since it was found to consist almost entirely of dark matter in 2016. New research has allowed for a collective sigh of relief, however.

Oct 14, 2020 11:09

The galaxy, located some 330 million light-years away in the Coma Cluster, contains 1,000 times fewer stars than the Milky Way, making it extremely dim.

Four years ago, astronomer Pieter van Dokkum of Yale University counted the number of clusters around the galaxy and, using the standard technique for determining the quantity of dark matter in an area of space, was startled by what he found.

Dragonfly 44 was apparently made up of 99.99 percent dark matter, a finding which, if confirmed, would have forced a massive overhaul of our physics, cosmological models and our entire understanding of the universe.

Dark matter cannot be observed directly, instead we can only observe its impacts on the universe around it, much like we can only see the wind rustling through the leaves or blowing debris about the streets.

In the case of dark matter, we can infer its presence by observing phenomena such as gravitational lensing, in which light bends around massive objects thanks to their immense gravity. The degree to which the light bends allows us to determine the mass of an object, for instance a galaxy.

Scientists then examine the galaxy and tally up all of the matter we can detect directly (on all electromagnetic wavelengths) including stars, planets, nebulae etc. This is then subtracted from the initial figure implied by the gravitational lensing, and voila, the amount of dark matter in a given area is determined.

A recount conducted by astronomer Teymoor Saifollahi of the Kapteyn Astronomical Institute in the Netherlands using the same Hubble Space telescope data as the initial study, but using far stricter criteria, found far less matter, and thus far less dark matter in Dragonfly 44.

“Dragonfly 44 (DF44) has been an anomaly all these years that could not be explained with the existing galaxy formation models,” said Saifollahi.

“Now we know that the previous results were wrong and that DF44 is not extraordinary. It is time to move on.”

These kinds of revisions help us refine our research into one of the most elusive, enigmatic but arguably most important aspects of our universe.

Using this technique, the scientific community's best guess places average dark matter concentrations across the universe at around 85 percent (though this figure varies depending on galaxy type) – a good deal short of the 99.99 percent originally suspected to inhabit Dragonfly 44.

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 Don't tell me you knew this ..   ... or you didn't? 

 

Closest to Earth ‘black hole’ turns out to be rare kind of star, after all

Closest to Earth ‘black hole’ turns out to be rare kind of star, after all

A growing body of research posits that the star system HR 6819 does not contain a black hole, contrary to earlier findings. It may instead boast a unique pair of stars.

Oct 20, 2020 11:58

The object located some 1,120 light-years from Earth has been preliminarily demoted from a bewildering black hole to a binary star system with a rather unusual orbit.

The system consists of a very hot Be spectral type star which spins at approximately 200km per second, shooting out a disc of hydrogen gas which surrounds it.

Previously, it was found to be accompanied by a B3 III star, measuring approximately six solar masses, with a roughly 40-day orbit. The Be star, also measuring in at about six solar masses, seemed to be spinning on the spot, which made no sense as two objects of similar mass should spin about a mutual center of gravity.

Following a serious amount of number crunching, researchers earlier this year concluded that the pair must be orbiting a third, massive object that wasn't visible which would explain why the spinning top star was essentially locked in place – a black hole.

...more ..

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I am goin' to ... "dark-matter-you"... just don't get me started ..

 

angel Physicists believe that dark matter has a propensity to structure itself into a hierarchy of haloes and subhaloes, via gravity. The masses of these clumps fall on a spectrum, with lower mass ones expected to be more numerous. Is there a limit to how light they could be? It depends on the nature of the dark matter particles. 

 

https://theconversation.com/dark-matter-our-method-for-catching-ghostly-...

 

The search for dark matter – an unknown and invisible substance thought to make up the vast majority of matter in the universe – is at a crossroads. Although it was proposed nearly 70 years ago and has been searched for intensely - with large particle colliders, detectors deep underground and even instruments in space – it is still nowhere to be found.

But astronomers have promised to leave “no stone unturned” and have started to cast their net wider out into the galaxy. The idea is to extract information from astrophysical objects that may have witnessed chunks of it as they were passing by. We have just proposed a new method of doing so by tracing galactic gas – and it may help tell us what it’s actually made of.

Physicists believe that dark matter has a propensity to structure itself into a hierarchy of haloes and subhaloes, via gravity. The masses of these clumps fall on a spectrum, with lower mass ones expected to be more numerous. Is there a limit to how light they could be? It depends on the nature of the dark matter particles.

Warm versus cold

Dark matter cannot be seen directly. We know it exists because we can see the gravitational effects it has on surrounding matter. There are different theories about what dark matter may actually be. The standard model suggests it is cold, meaning it moves very slowly and only interacts with other matter through the force of gravity. This would be consistent with it being made up of particles known as axions or WIMPS. Another theory, however, suggests it is warm, meaning it moves at higher speeds. One such particle candidate is the sterile neutrino.

If dark matter is cold, a Milky Way-type galaxy could harbour one or two subhaloes weighing as much as 1010 Suns, and most likely hundreds with masses of around 108 Suns. If dark matter is warm, haloes lighter than around 108 Suns cannot form easily. So tallying light mass dark haloes can tell us something about the nature of dark matter.

Halo imprints

We believe that the existence of lower mass haloes can be revealed by carefully planned observations. Astronomers have already got pretty good at this game of hide and seek with dark matter haloes and have devised observations to pick up the damage they leave behind.

To date, observations have targeted mostly the changes in the distribution of stars in the Milky Way. For example, the Large Magellanic Cloud, a smaller galaxy orbiting ours, seems to have a dark matter halo which is massive enough to trigger an enormous wake – driving the stars from across vast regions to move in unison.

A few of the smaller dark matter haloes thought to be whizzing inside the Milky Way may occasionally pierce through large stellar features, such as globular clusters (spherical collection of stars), leaving tell-tale gaps in them. Dark matter haloes can also affect how light bends around astrophysical objects in a process called gravitational lensing.

But the signals left in the stellar distributions are weak and prone to confusion with the stars’ own motions. Another way to probe the effect of haloes is by looking at the galactic gas it affects. Galaxies have plenty of hot gas (with a temperature of around 106 degrees Kelvin) which extends out to their edge, providing a wide net for catching these dark matter haloes.

Using a combination of analytical calculations and computer simulations, we have shown that dark haloes heavier than 108 solar masses can compress the hot gas through which they are moving. These will create local spikes in the density of the gas, which can be picked up by X-ray telescopes. These are predicted to be minute, of the order of a few per cent, but they will be within the reach of the upcoming Lynx and Athena telescopes.

Our models also predict that the spikes in the density of the cooler galactic gas (with temperature of around 105 K) will be even more significant. This means that the cooler gas can record the passage of dark matter haloes even more sensitively than the hot gas.

Another promising way of observing the dark-matter-induced fluctuations in the gas is via the photons (light particles) from the cosmic microwave background – the light left over from the Big Bang. This light scatters off the highly energetic electrons in the hot gas in a way that we can detect, providing a complementary approach to the other studies.

Over the next few years, this new method can be used to test models of dark matter. Regardless of whether dark matter haloes below 108 solar masses are found in the numbers predicted or not, we will learn something useful. If the numbers match up, the standard cosmological model would have passed an important test. If they are missing, or are far fewer than expected, the standard model would be ruled out and we’ll have to find a more viable alternative.

Dark matter remains a mystery, but there’s a huge amount of work going into solving it. Whether the answer will come from instruments on Earth or astrophysical probes, it will no doubt be one of the most important discoveries of the century.

 

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https://theconversation.com/the-scariest-things-in-the-universe-are-blac...

 

The scariest things in the universe are black holes – and here are 3 reasons

 

Halloween is a time to be haunted by ghosts, goblins and ghouls, but nothing in the universe is scarier than a black hole.

Black holes – regions in space where gravity is so strong that nothing can escape – are a hot topic in the news these days. Half of the 2020 Nobel Prize in Physics was awarded to Roger Penrose for his mathematical work showing that black holes are an inescapable consequence of Einstein’s theory of gravity. Andrea Ghez and Reinhard Genzel shared the other half for showing that a massive black hole sits at the center of our galaxy.

Black holes are scary for three reasons. If you fell into a black hole left over when a star died, you would be shredded. Also, the massive black holes seen at the center of all galaxies have insatiable appetites. And black holes are places where the laws of physics are obliterated.

I’ve been studying black holes for over 30 years. In particular, I’ve focused on the supermassive black holes that lurk at the center of galaxies. Most of the time they are inactive, but when they are active and eat stars and gas, the region close to the black hole can outshine the entire galaxy that hosts them. Galaxies where the black holes are active are called quasars. With all we’ve learned about black holes over the past few decades, there are still many mysteries to solve.

Death by black hole

Black holes are expected to form when a massive star dies. After the star’s nuclear fuel is exhausted, its core collapses to the densest state of matter imaginable, a hundred times denser than an atomic nucleus. That’s so dense that protons, neutrons and electrons are no longer discrete particles. Since black holes are dark, they are found when they orbit a normal star. The properties of the normal star allow astronomers to infer the properties of its dark companion, a black hole.

The first black hole to be confirmed was Cygnus X-1, the brightest X-ray source in the Cygnus constellation. Since then, about 50 black holes have been discovered in systems where a normal star orbits a black hole. They are the nearest examples of about 10 million that are expected to be scattered through the Milky Way.

Black holes are tombs of matter; nothing can escape them, not even light. The fate of anyone falling into a black hole would be a painful “spaghettification,” an idea popularized by Stephen Hawking in his book “A Brief History of Time.” In spaghettification, the intense gravity of the black hole would pull you apart, separating your bones, muscles, sinews and even molecules. As the poet Dante described the words over the gates of hell in his poem Divine Comedy: Abandon hope, all ye who enter here.

A hungry beast in every galaxy

Over the past 30 years, observations with the Hubble Space Telescope have shown that all galaxies have black holes at their centers. Bigger galaxies have bigger black holes.

Nature knows how to make black holes over a staggering range of masses, from star corpses a few times the mass of the Sun to monsters tens of billions of times more massive. That’s like the difference between an apple and the Great Pyramid of Giza.

Just last year, astronomers published the first-ever picture of a black hole and its event horizon, a 7-billion-solar-mass beast at the center of the M87 elliptical galaxy.

It’s over a thousand times bigger than the black hole in our galaxy, whose discoverers snagged this year’s Nobel Prize. These black holes are dark most of the time, but when their gravity pulls in nearby stars and gas, they flare into intense activity and pump out a huge amount of radiation. Massive black holes are dangerous in two ways. If you get too close, the enormous gravity will suck you in. And if they are in their active quasar phase, you’ll be blasted by high-energy radiation.

How bright is a quasar? Imagine hovering over a large city like Los Angeles at night. The roughly 100 million lights from cars, houses and streets in the city correspond to the stars in a galaxy. In this analogy, the black hole in its active state is like a light source 1 inch in diameter in downtown LA that outshines the city by a factor of hundreds or thousands. Quasars are the brightest objects in the universe.

Supermassive black holes are strange

The biggest black hole discovered so far weighs in at 40 billion times the mass of the Sun, or 20 times the size of the solar system. Whereas the outer planets in our solar system orbit once in 250 years, this much more massive object spins once every three months. Its outer edge moves at half the speed of light. Like all black holes, the huge ones are shielded from view by an event horizon. At their centers is a singularity, a point in space where the density is infinite. We can’t understand the interior of a black hole because the laws of physics break down. Time freezes at the event horizon and gravity becomes infinite at the singularity.

The good news about massive black holes is that you could survive falling into one. Although their gravity is stronger, the stretching force is weaker than it would be with a small black hole and it would not kill you. The bad news is that the event horizon marks the edge of the abyss. Nothing can escape from inside the event horizon, so you could not escape or report on your experience.

[Deep knowledge, daily. Sign up for The Conversation’s newsletter.]

According to Stephen Hawking, black holes are slowly evaporating. In the far future of the universe, long after all stars have died and galaxies have been wrenched from view by the accelerating cosmic expansion, black holes will be the last surviving objects.

The most massive black holes will take an unimaginable number of years to evaporate, estimated at 10 to the 100th power, or 10 with 100 zeroes after it. The scariest objects in the universe are almost eternal.

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 Now, you know ... what I've 'discovered' yesterday ...

 

Strange ‘electron’ object discovered around binary black holes could shed light on dark matter & space-time mysteries

A team of astronomers have discovered a strange object that can exist around a pair of black holes. The discovery could help to unravel the identity of dark matter and reveal the nature of space-time.

Nov 15, 2020 16:51

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You were convinced black holes in the Universe are acting as some huge garbage containers ..., but that ain't a fact.

 

Black holes were/are there first ... and contribute to the Universe creation ... he he.

 

Watch 90' presentation of physic Nassim Haramein with the title "Black Wholes" 2010, and get an explanation of the term "singularity" and "vacuum as connector"... of everything.

 

 

https://www.gaia.com/video/black-whole

 

Flick's free d/l over FrostWire ... or if you register at Gaia ...

 

 

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I heard a blackhole was detected by a drunk foreign junkie in a sleazy bar carpark somewhere in Shanghai.

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yeah,, this 'Topic' is one very big set-up for Blue jokes!   *get it,, haha,, blue,, not black,,, I feel like Kramer explaining to Jerry.  

 

anyway,,, here goes......

 

all I can come up with is punch-line,,, 'baby, that's not a hole at all!'  bada boom ~

 

ok,, I'll leave it to others to make with the funny. 

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This looks  like women are really from the Sun ..., 

 

 

Sauron, is that you? World’s largest solar observatory releases incredible, if ominous, close-up of sunspot

Sauron, is that you? World’s largest solar observatory releases incredible, if ominous, close-up of sunspot

Researchers working at the world’s largest solar observatory have shared a test image showing the surface of the sun in unprecedented detail, with more to come as our star enters a possible record-breaking period of activity.

Dec 8, 2020 11:03

 

... doesn't it .. ? 

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Black holes can grow ‘hair’ when spinning fast enough in dramatic extension of Einstein’s theory of gravity

Black holes can grow ‘hair’ when spinning fast enough in dramatic extension of Einstein’s theory of gravity

An international team of scientists has found that black holes can grow hair-like structures if they spin fast enough, providing fresh insights at the fringe of our understanding of the universe.

Dec 9, 2020 15:52

In a new study, researchers used numerical simulations which indicated that black holes can spontaneously erupt what has been described as a hair (otherwise known as a scalar field), once they reach a certain spin speed.

This new insight into the behavior of fast-spinning black holes or neutron stars would come as an extension to Einstein’s theory of gravity.

“While previous studies have already provided examples of 'hairy' black hole solutions, we have shown for the first time, thanks to numerical simulations, that black holes can spontaneously grow the simplest form of permanent hair (a scalar field) once they start spinning fast enough,” says Alexandru Dima, astrophysicist at SISSA and INFN and first author of the paper.

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First Radio Signals From Planet Outside Solar System Could Have Been Received, Astronomers Say

 

...locusts, plague, and now... aliens? 

 

SUN DEC 20, 2020 AT 12:30 AM

 

“We present one of the first hints of detecting an exoplanet in the radio realm,” said Jake D. Turner, a postdoctoral researcher at Cornell University who helped spearhead the study, the findings of which are reported in the journal Astronomy & Astrophysics.

“The signal is from the Tau Boötes system, which contains a binary star and an exoplanet,” Turner added.

“We make the case for an emission by the planet itself. From the strength and polarization of the radio signal and the planet’s magnetic field, it is compatible with theoretical predictions.”

Furthermore, in order to verify the origin of the bursts, additional research must be conducted. However, if it is the case, then it will offer a completely new way to understand worlds that are many light years away, according to The Independent.

By utilizing a radio telescope in the Netherlands, the astronomers discovered the bursts. They located signals emanating from a star system that is a host to a variety of planet known as a hot Jupiter, which is massive and gaseous like Earth’s neighbor but much closer to its own system’s star, per The Independent.

“If confirmed through follow-up observations,” explains Ray Jayawardhana, a Cornell professor and a co-author on the new research, “this radio detection opens up a new window on exoplanets, giving us a novel way to examine alien worlds that are tens of light-years away.”

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Quick update ... from the constellation Fornax ... many ... 45 million light years away ...

 

Spectacular ‘rose’ of star-forming regions snapped encircling distant supermassive black hole

Spectacular ‘rose’ of star-forming regions snapped encircling distant supermassive black hole

In a galaxy far, far away, astronomers have discovered an incredibly beautiful phenomenon which sees a star-bursting ring surrounding a supermassive black hole, like the petals of a rose.

The European Southern Observatory captured the stunning stellar light show thanks to the MUSE instrument on its Very Large Telescope (VLT).

The magnificent image captures the distant spiral galaxy known as NGC 1097, which is located 45 million light-years away from Earth, in the constellation of Fornax.

A supermassive black hole lies at the center of the fascinating galaxy and the extraordinary ring of star-forming regions entirely encircles it.

Research indicates that the glowing ring of star-forming regions have a network of gas and dust that spirals to the black hole. The ESO said the image shows a “textbook example” of a star-bursting nuclear ring.

The ring births new stars thanks to an inflow of material towards the center of the galaxy. It stretches approximately 5,000 light-years in diameter, meaning it is dwarfed by the full size of the galaxy which extends tens of thousands of light-years beyond it.

The darker lanes captured in the MUSE image show dust, gas and debris being funneled into the supermassive black hole.

“This process heats up the surrounding matter forming an accretion disc around the black hole and launching huge amounts of energy into the surrounding area,” the ESO explained.

“Nearby dust is heated up and star formation accelerates in the area around the supermassive black hole, forming the star-bursting nuclear ring shown in pink and purple tones in the image,” it added.

MUSE, which stands for Multi-Unit Spectroscopic Explorer, is attached to one of the four, 8.2-meter telescopes that make up the Very Large Telescope. Its unique design allows researchers to map complex mechanisms within many galaxies and analyse the formation of stars and star clusters.

The telescope is positioned at the ESO’s Paranal Observatory in the Atacama Desert of northern Chile.

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After an extensive search, I found the entrance to a black holi-ness. In case OP is interested, please contact me through PM (private massage)! 

 

https://www.rt.com/news/514460-humans-safely-enter-black-holes/

 

A pair of physicists have proposed the exact set of circumstances necessary for a human to enter a black hole, but caution that it would be the loneliest one-way trip ever undertaken in the history of mankind.

For the purposes of their proposal, Leo and Shanshan Rodriquez, both assistant professors of physics at Grinnell College, compared two types of black hole: stellar-sized, with roughly the same mass as our sun, and supermassive, with a mass millions or even billions of times larger. 

The former does not rotate, with an event horizon radius of approximately two miles (3.2km). The event horizon is the point of no return where the gravitational or tidal forces of the black hole become so powerful that not even light can escape.

RTA person falling into a black hole and being stretched. © Leo Rodriguez/Shanshan Rodriguez/CC BY-ND

By contrast, supermassive black holes like the one at the center of the Milky Way galaxy can measure up to and beyond four million solar masses, with an event horizon radius of 7.3 million miles. 

In the case of a stellar-sized black hole, the event horizon is far closer to its center than a supermassive black hole, meaning that the difference in terms of gravitational pull between the event horizon and its center is somewhere in the region of 1,000 billion times. 

If a person were to cross the event horizon of a stellar-sized black hole, they would undergo a process known as spaghettification, in which all the atoms of their body would be stretched out in a long thing strand given the extraordinary difference in gravitational pull from one point in spacetime to the next. It is highly likely that this process would kill the intrepid astronaut. 

However, a person falling into a supermassive black hole would experience a much more gradual and protracted freefall without the unsightly spaghettification, passing through the event horizon unaffected by extreme differences in gravity given the staggering distances involved.

RT© Leo and Shanshan Rodriguez/CC BY-ND)

One other obstacle stands in the way of this extreme freefall though; most black holes have extremely hot accretion discs of superheated material ripped from the universe around them which is being crushed together on their doorstep.

In order for a human to “safely” enter a supermassive black hole, it would need to be isolated from the universe around it, having chowed down on planets, gas and stars around it long before the intrepid astronaut dared to approach the event horizon. 

 

Alas, surviving the journey past the event horizon would be the most lonely and personal voyage ever undertaken, as no information can possibly escape the black hole, given the aforementioned gravitational tidal forces which light itself cannot escape.

 

 

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... am reporting straight from Spain ... and it's about yer DNA, in case you were wondering ... like me ... 

 

Spanish stargazers discover a new hidden structure in the Milky Way, with clues to the building blocks of our DNA

Spanish stargazers discover a new hidden structure in the Milky Way, with clues to the building blocks of our DNA

Spanish astronomers say they have completed the most accurate picture yet of the Milky Way and have discovered a huge new hidden structure made up of massive blue stars spanning 10,000 light-years.

Apr 1, 2021 15:03

 

Astronomers had already known that the Milky Way consists of great spiral arms of stars, but the scientists from Spain’s Centro de Astrobiología (CAB) put together the most detailed map yet of the Orion arm, where our solar system is, along with those of Perseus at the outer edge of the Milky Way, and Sagittarius, located towards the center of our galaxy.

 

They were able to detect the previously unknown region of our galaxy through observations form the European space Agency’s Gaia telescope and called it “the Cepheus spur.”
“The moment of discovery of the spur was curious,” Michelangelo Panteleoni Gonzalez, a lead researcher at CAB, told Spanish newspaper El Pais. “It wasn’t an explosive revelation, but there was something inside me that was transformed. It is what hooks you and what gives meaning to so much effort.”

He and colleague Jesus Maiz Apellaniz have published their findings in a paper to the Royal Astronomical Society.

 

They say it is a bridge of massive blue stars that spans a branch 10,000 light years in length, exits the spiral arm of Orion and connects to Perseus.

The study says the spur is a compact structure of stars that appears to have consistent motion and is located about 300 light years high above the midplane of the galaxy.

Astronomers looking at other galaxies had observed similar height consistencies, but the pair’s discovery is the first time that it has been confirmed in our home galaxy.

 

“In the galactic map that we have drawn… an over-density of stars is observed in a space that was previously apparently empty,” said Panteleoni.

Blue stars are the largest, rarest and hottest stars in the galaxy. Of the estimated 400 billion stars in the Milky Way, less than one in a million is a blue star. While the surface of a star like the Sun is around 5,500 degrees Celsius, the temperatures on blue stars exceed 30,000C and are tens of times their mass.

Apellaniz and Pantaleoni said the blue stars are the most interesting objects in the universe because the nuclear reactions that occur inside them are particularly violent, making them factories where the largest elements in the universe are created.

 

“The elements that our planet is made of, such as silicon or phosphorous atoms in our DNA, mostly come from inside stars of this type that died billions of years ago,” Pantaleoni added. 

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Has anybody seen OP   recently?  

 

We have an answer or in other words, Einstein was right ... surprise

 

https://news.yahoo.com/astronomers-see-back-black-hole-141927796.html

 

 

  Astronomers see the back of a black hole for the first timeAstronomers see the back of a black hole for the first time

Astronomers have managed to look behind a black hole for the first time and have proved that Albert Einstein was right about how these mysterious celestial behemoths behave.

An international team of researchers used high-powered X-ray telescopes to study a supermassive black hole 800 million light years away at the centre of a distant galaxy.

The researchers saw the usual hallmarks of a black hole, but they also spotted light – in the form of X-rays – which was being emitted by the far side of the black hole.

Black holes are born when a gargantuan star explodes in a supernova and then collapses in on itself. This forms an incomprehensibly dense material which swallows up everything in its general vicinity, and therefore it should be impossible to see light from the back of a black hole.

However, Einstein’s dogmatic theory of general relativity predicted in 1915 that the gravitational pull of black holes is likely so enormous that they warp the very fabric of space, twisting magnetic fields and bending light.

As a result, Einstein’s work asserted that it should be possible to see light waves ejected from the far side of the black hole because of the distorted magnetic fields acting as a mirror.

Experts accepted the theory, but have been unable to directly observe the phenomenon until now, thanks to modern telescopes and the development of highly sensitive instruments.

Dan Wilkins, an astrophysicist at Stanford University, was studying the mechanics of how a black hole rips atoms and electrons apart, and the X-rays this subsequently produces. Upon inspecting the data he saw what he expected, X-rays spewed directly towards Earth from the black hole’s core, but he also saw unexpected echoes shortly afterwards.

These, he said, were X-rays which were flung out in the opposite direction of Earth, but were reflected by the black hole’s mangled magnetic field.

The finding, published in Nature, yet again proves Einstein was correct, and further backs up the theory of general relativity.

“Fifty years ago, when astrophysicists starting speculating about how the magnetic field might behave close to a black hole, they had no idea that one day we might have the techniques to observe this directly and see Einstein’s general theory of relativity in action,” said Prof Roger Blandford, a co-author of the research, also from Stanford University.

 

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