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New Wrinkle Added to Cosmology’s Hubble Crisis

Source: quantamagazine.org
Date: 26 February, 2020

A problem confronts cosmology: Two independent measurements of the universe’s expansion give incompatible answers. Now a third method, advanced by an astronomy pioneer, appears to bridge the divide.

. Then in July, a new measurement of cosmic expansion using objects called quasars, when combined with the other measurement, pushed past “five sigma,” a statistical level that physicists usually treat as their standard of proof of an unaccounted-for physical effect. In this case, cosmologists say there might be some extra cosmic ingredient, beyond dark matter, dark energy and everything else they already include in their equations, that speeds the universe up.

But that’s if the measurements are correct. A new line of evidence, first announced last summer, suggests that the cosmic expansion rate may fall much closer to the rate predicted by early-universe measurements and the standard theory of cosmology.

https://www.quantamagazine.org/new-wrinkle-added-to-cosmologys-hubble-crisis-20200226/
And they just keep on moving the goalposts.
 

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Our galaxy’s huge black hole may have created organic molecules

Source: newscientist.com
Date: 26 February, 2020

The Milky Way’s black hole may have given life a helping hand

The supermassive black hole at the centre of the Milky Way may have been crucial to the evolution of life in the galaxy.

These days, the black hole, known as Sagittarius A*, is relatively calm. But there are hints that millions of years ago it may have been much more active, swallowing down matter and spewing out high-energy radiation including large amounts of X-rays.

https://www-newscientist-com.cdn.am...3A%2F%2Fwww.google.com&amp_tf=From%20%251%24s
 

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Starter' Earth grew in a flash. Here's how the planet did it.

Source: livescience.com
Date: 24 February, 2020

If the solar system formed in 24 hours, then proto-Earth formed in just 1.5 minutes.

Dust from meteorites that crash-landed on Earth have revealed that Earth's precursor, known as proto-Earth, formed much faster than previously thought, a new study finds.

An analysis of this meteorite dust showed that proto-Earth formed within about 5 million years, which is extremely fast, astronomically speaking.

Put another way, if the entire 4.6 billion years of the solar system's existence were compressed into a 24-hour period, proto-Earth formed in just 1 minute and 30 seconds, the researchers said.

The new finding breaks with the previously held idea that proto-Earth formed when larger and larger planetary bodies randomly slammed into one another, a process that would have taken several tens of millions of years, or about 5 to 15 minutes in the fictional 24-hour timescale.

https://www-livescience-com.cdn.amp...m/meteorite-iron-shows-earth-formed-fast.html
 

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THE UNIVERSE MIGHT JUST BE CURVED

Source: John Hopkins University
Date: 26 February, 2020

A recent analysis of the cosmic microwave background by Johns Hopkins cosmologist Joseph Silk and others suggests that maybe, just maybe, the universe could be sphere-shaped, a theory that contradicts the conventional idea that the universe stretches infinitely in all directions

More than 2,000 years ago, the ancient Greeks figured out that Earth was round rather than flat. Now, cosmologist Joseph Silk thinks the same might be true of the entire universe.

Together with colleagues in Italy and the United Kingdom, Silk recently analyzed data from the Planck Collaboration, a European Space Agency project that from 2009 to 2013 mapped the cosmic microwave background, a wash of low-level radiation that fills the sky. Cosmologists have been probing Planck's data on the CMB—a remnant of the first light to flood the universe after the big bang more than 13 billion years ago—to better understand conditions in the early universe and reconstruct how the cosmos evolved over time.

While the CMB is fairly uniform and quite dim, it nonetheless displays minute peaks and valleys in intensity, like hot and cold spots on a temperature map. These tiny fluctuations represent variations in the energy density of the early universe. And those variations eventually translated into differences in the density of matter, with the hot spots giving rise to the clusters of galaxies that are now strewn across the sky like seeds bearing fruit in a celestial garden—even as traces of the seeds themselves remain fixed in the CMB.

"It's a bit like archaeology," Silk explains. "We're looking at the fossil record of everything that formed subsequently."

Silk and his colleagues noticed something odd about the Planck data, however: The peaks in the CMB were smoother than predicted. They attributed this to a phenomenon called gravitational lensing, whereby the light of the CMB is bent and diffused by gravity—in this case, the gravity exerted by dark matter, the unseen exotic material that makes up roughly a quarter of the universe. Yet astronomers already know how much dark matter exists, and there isn't enough to account for the gravitational lensing indicated by the Planck data.

[...]

Assuming that the universe is curved may have solved the lensing problem, but it comes at a price.

https://hub.jhu.edu/2020/02/26/closed-universe-curve-999-em1-art1-nr-science/
 

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Astronomers detect biggest explosion in the history of the Universe

Source: phys.org
Date: 1 hour ago

International Centre for Radio Astronomy
Scientists studying a distant galaxy cluster have discovered the biggest explosion seen in the Universe since the Big Bang.

The blast came from a supermassive black hole at the centre of a galaxy hundreds of millions of light-years away.

It released five times more energy than the previous record holder.

Professor Melanie Johnston-Hollitt, from the Curtin University node of the International Centre for Radio Astronomy Research, said the event was extraordinarily energetic.

"We've seen outbursts in the centres of galaxies before but this one is really, really massive," she said.

"And we don't know why it's so big.

"But it happened very slowly—like an explosion in slow motion that took place over hundreds of millions of years."

The explosion occurred in the Ophiuchus galaxy cluster, about 390 million light-years from Earth.

It was so powerful it punched a cavity in the cluster plasma—the super-hot gas surrounding the black hole.

Lead author of the study Dr. Simona Giacintucci, from the Naval Research Laboratory in the United States, said the blast was similar to the 1980 eruption of Mount St. Helens, which ripped the top off the mountain.

"The difference is that you could fit 15 Milky Way galaxies in a row into the crater this eruption punched into the cluster's hot gas," she said.

Professor Johnston-Hollitt said the cavity in the cluster plasma had been seen previously with X-ray telescopes.

But scientists initially dismissed the idea that it could have been caused by an energetic outburst, because it would have been too big.

https://phys-org.cdn.ampproject.org...omers-biggest-explosion-history-universe.html
 

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...The explosion occurred in the Ophiuchus galaxy cluster, about 390 million light-years from Earth. ..

How do they come to this kind of conclusion ?
 

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What specifically bothers you?

I only have a vague grasp of this!
What I find annoying..No, too strong, frustrating is that these cosmologists just keep on adding more 'well, maybe it's...' to the theory. Either the Standard Model of Cosmology is correct, or it isn't. There needs to be more emphasis on proving beyond all reasonable doubt the parts that the theory is comprised of.
Maybe the problem is further back in the way the model was constructed and they are working on a false premise. Some, maybe quite small, error that is screwing the whole thing up.

By all means keep on with the search, but let's see something positive.

INT21.
 

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The Milky Way Is Warped, And It May Be The Legacy of an Ongoing Galactic Collision

Source: sciencealert.com
Date: 3 March, 2020

The Milky Way isn't like other barred spiral galaxies. Instead of a nice, tidy flat disc, it has a kink in its spine, a twist in its swagger. As we have long known, and two separate studies recently confirmed, the Milky Way is seriously warped around the edges, a strange idiosyncrasy that's been puzzling astronomers for years.

Now a new analysis of data from the Gaia mission has ponied up an explanation: it's the result of a collision with a smaller galaxy sometime in the Milky Way's murky past.

It's unclear when, or which galaxy. But the way the warp whirls around the galactic centre seems like it could only have been caused by a relatively recent, or even ongoing, kerfuffle with one of the Milky Way's satellite galaxies.

The Gaia mission has already done great work revealing our galaxy's somewhat violent past.

A collision with another galaxy 8 to 11 billion years ago puffed up the Milky Way's thick disk, filling it with stars. An encounter with a ghost galaxy millions of years ago left ripples in the Milky Way's hydrogen. And let's not forget a smash-up with a galaxy called the Gaia Sausage, which left stars reeling about in peculiar orbits.

https://www.sciencealert.com/the-mi...-because-of-an-ancient-galactic-collision/amp
 
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Strange 'Super-Puff' Planets Floating in Space Might Not Be What We Thought

Source: sciencealert.com
Date: 3 March, 2020

As we find more and more exoplanets in the Milky Way - numbering in the thousands now - astronomers are discovering some strange objects that don't exist in the Solar System. One such phenomenon are the strangely fluffy "super-puff" planets - the size of gas giants, but way, way less massive.

Exactly how these planets can exist has been a puzzle to astronomers. In extreme cases, a super-puff planet can be less than one percent of the mass of a gas giant of similar size. Now researchers have crunched the numbers and come up with a new explanation: What if they are actually smaller planets with giant rings?

This could solve some of the stranger aspects of super-puff planets, as well as help us to find a feature that has so far proven elusive on exoplanets: planetary rings.

"In principle, rings should be detectable from detailed photometric or spectroscopic changes to transits. The difficulty is that such signals are subtle and difficult to discern in current data," the researchers wrote in their paper.

"There is clearly still a lot we do not know about the rings of exoplanets."

https://www.sciencealert.com/the-puffiness-of-super-puff-planets-could-be-huge-rings/amp
 

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No Galaxy Will Ever Truly Disappear, Even In A Universe With Dark Energy

Source: Forbes
Date: 4 March, 2020

And yet, despite all of this, there are more galaxies that we can observe today, 13.8 billion years after the hot Big Bang, than at any prior point in our cosmic history. Even more puzzling: as time goes on, the number of potentially observable galaxies will increase, more than doubling as the cosmological clock continues ticking by. Even as they recede faster and faster, not a single galaxy will ever disappear from our view entirely. Here’s the puzzling science of how this happens.

https://www.forbes.com/sites/starts...pear-even-in-a-universe-with-dark-energy/amp/
 

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THEORETICAL HOLES IN SPACETIME COULD SWALLOW THE ENTIRE UNIVERSE

Source: futurism.com
Date: 6 March, 2020

In a new paper, physicists argue that extradimensional holes known as “bubbles of nothing” could cause the universe to consume itself from the inside out, Motherboard reports.

Three researchers from the University of Oviedo in Spain and the University of Uppsala in Sweden submitted a paper, appropriately titled “Nothing Really Matters,” to the Journal of High-Energy Physics this month — about a hypothetical, mind-bending hole that could destroy the entire universe.

The paper revives a theory that dates back to 1982, by theoretical physicist Edward Witten.

“A hole spontaneously forms in space and rapidly expands to infinity, pushing to infinity anything it may meet,” Witten wrote in his paper.

Physicists have long posited that most of our universe is made up of nothingness, or vacuum. Anything in a more “excited” or unstable state tends to decay to lower energy states by releasing energy. That means our universe is relatively stable.

https://futurism.com/the-byte/theoretical-holes-spacetime-swallow-entire-universe
 

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Faster-Than-Light Speeds Could Be Why Gamma-Ray Bursts Seem to Go Backwards in Time

Source: sciencealert.com
Date: 7 March, 2020

Time, as far as we know, moves only in one direction. But in 2018, researchers found events in some gamma-ray burst pulses that seemed to repeat themselves as though they were going backwards in time.

Now, recent research suggests a potential answer for what might be causing this time reversibility effect. If waves within the relativistic jets that produce gamma-ray bursts travel faster than light - at 'superluminal' speeds - one of the effects could be time reversibility.

Such speeding waves could actually be possible. We know that when light is travelling through a medium (such as gas or plasma), its phase velocity is slightly slower than c - the speed of light in a vacuum, and, as far as we know, the ultimate speed limit of the Universe.

Therefore, a wave could travel through a gamma-ray burst jet at superluminal speeds without breaking relativity. But to understand this, we need to back up a little to look at the source of those jets.

https://www.sciencealert.com/faster...a-ray-bursts-seem-to-go-backwards-in-time/amp
 

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Scientists Claim to Have Found The First Known Extraterrestrial Protein in a Meteorite

Source: sciencealert.com
Date: 2 March, 2020

A new discovery could be a clue for us to see if life could emerge elsewhere in the Solar System. Using a new analysis technique, scientists think they have found an extraterrestrial protein, tucked inside a meteorite that fell to Earth 30 years ago.

If their results can be replicated, it will be the first protein ever identified that didn't originate here on Earth.

"This paper characterises the first protein to be discovered in a meteorite," the researchers wrote in a paper uploaded to preprint server arXiv. Their work is yet to be peer reviewed, but the implications of this finding are noteworthy.

https://www.sciencealert.com/scient...n-extraterrestrial-protein-in-a-meteorite/amp
 

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In case you need a seemingly bigger issue to take your mind off the coronavirus pandemic, this might be the headline for you ...

Ancient Supermassive Black Hole Has Its Particle Beam Aimed Right at Earth

FULL STORY: https://www.sciencealert.com/scient...ar-aiming-its-particle-beam-directly-at-earth
So... the light from this 'blazar' (cool term I've not come across before) was emitted 13 billion years ago... (I am always in awe to think that we are seeing celestial objects as they were all that long ago)

... is there any way of knowing if the blazar is still there now? The article talks about it in the present tense, but... it might not be there now, am I right? Or it could have changed? But we wouldn't know it for some time (if we even lived long enough that is)?

(Like if something happens to the sun we only see it 8 minutes later or somesuch).... but obviously with this blazar its quite a bit longer than that....
 

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The factor that motivated me to post about this in the Fortean Headlines thread was the ominous-sounding bit about the blazar's "particle beam" being aimed directly at earth.

If it weren't aimed in our direction it wouldn't be recognized as a blazar. We can reliably observe "blazing" of directional bursts from such objects only if they're aimed at us.

The originating object may well have gone extinct before earth even formed, and the light indicating such an extinction may not arrive here in our Sol system until earth itself is long gone.

The more pressing issue would be whether or not such blazars can or do emit beams as potentially dangerous as gamma ray bursts. If such a lethal emission is possible, it means our ability to see such objects as blazars implies we are by definition "in their line of fire", so to epeak.
 

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The factor that motivated me to post about this in the Fortean Headlines thread was the ominous-sounding bit about the blazar's "particle beam" being aimed directly at earth.

If it weren't aimed in our direction it wouldn't be recognized as a blazar. We can reliably observe "blazing" of directional bursts from such objects only if they're aimed at us.

The originating object may well have gone extinct before earth even formed, and the light indicating such an extinction may not arrive here in our Sol system until earth itself is long gone.

The more pressing issue would be whether or not such blazars can or do emit beams as potentially dangerous as gamma ray bursts. If such a lethal emission is possible, it means our ability to see such objects as blazars implies we are by definition "in their line of fire", so to epeak.
The particle beam is interesting and I should have commented more about it, I do apologise. I also find it ominous that it is aimed directly at us... I can just imagine when they found out... "where's it pointing?" "erm... right at us" :)

Even if the blazar is long gone, the beam, being pointed at us, would still eventually 'reach' us, is that right?...

... Or should I say 'zap' us...


According to this article, gamma ray bursts can indeed be emitted from blazars... https://blogs.voanews.com/science-w...ys-from-halfway-across-the-universe-detected/

So in the line of fire, indeed, it would seem.
 

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... Even if the blazar is long gone, the beam, being pointed at us, would still eventually 'reach' us, is that right?...
In principle - yes.

The light we see from the ancient blazar cited here left the blazar circa 13 billion years ago. Any changes (including emission of a different / more dangerous burst) may be billions of years in the blazar's past but who-knows-how-many years in our own future at this relatively remote location.

I'm not sure how focused or how energetic a gamma ray burst would be if it had traveled from as far away as far as the most ancient blazar cited here.

Still, this same situation applies to all the other blazars we've identified.
 

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How to see bright Comet ATLAS
Posted by Eddie Irizarry in SPACE | March 22, 2020
Recently discovered comet C/2019 Y4 (ATLAS) isn’t bright enough to see with the unaided eye … yet. But it’s getting brighter. Will it provide a good show or fizzle out? Click here to learn more.

A recently discovered comet is getting the attention of astronomers and sky enthusiasts as it’s become brighter than expected in the last few days. Astronomers using the ATLAS (Asteroid Terrestrial-impact Last Alert System) in Hawaii discovered Comet C/2019 Y4 (ATLAS) on December 28, 2019. As of mid-late March, it shines at about the brightness of an 8th-magnitude star – not visible to the eye yet – but within reach of medium-sized telescopes in dark skies. The comet is currently crossing Mars’ orbit and is approaching the inner solar system. As it gets closer to us, it’ll get brighter still. You’ll find charts for observers at the bottom of this post.
Comet ATLAS should become bright enough to be easily visible in binoculars, and perhaps bright enough to be seen with the unaided eye from dark sky locations.
etc
https://earthsky.org/space/how-to-see-bright-comet-c-2019-y4-atlas
 

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The comet mentioned upthread is getting brighter...

https://www.space.com/comet-atlas-may-be-brightenting.html

The possible celestial showpiece is known as Comet ATLAS, or C/2019 Y4. When it was discovered on Dec. 28, 2019, it was quite faint, but since then, it has been brightening so rapidly that astronomers have high hopes for the spectacle it could put on. But given the tricky nature of comets, skywatchers are also being cautious not to get their hopes up, knowing that the comet may fizzle out.
And...

Until a couple of weeks ago, it was brightening at an astounding rate. That brightening has slowed somewhat, but it is still an impossible rate of brightening to maintain. Were ATLAS to continue to brighten at this rate all the way to its closest approach to the sun at the end of May, it would end up rivaling the planet Venus in brightness!
So... will it get amazingly bright just in time for us all to see it?
 
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