Researchers Identified the Source of Supermassive Black Hole Flares to be Magnetic "Reconnection" around the Event Horizon. - Optic Flux | Canada News Media
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Researchers Identified the Source of Supermassive Black Hole Flares to be Magnetic "Reconnection" around the Event Horizon. – Optic Flux

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Largest-ever simulations point to flickering caused by magnetic reconnection.’

Breaking and reconnecting magnetic field lines at the event horizon unleash the energy from a black hole’s magnetic field, speeding particles that cause intense flares, according to researchers at the Flatiron Institute and its partners.

The discoveries point to fascinating new possibilities for studying black holes.

Black holes do not necessarily exist in complete darkness.

Astronomers have discovered powerful light displays just beyond the event horizons of supermassive black holes, including the one at the center of our galaxy.

However, scientists could not determine the source of these flares other than the possible participation of magnetic fields.

Physicists claim to have answered the puzzle by using computer models of unprecedented power and resolution: energy produced near a black hole’s event horizon during the reconnection of magnetic field lines propels the flares, the researchers explain in The Astrophysical Journal Letters.

According to the new models, interactions between the magnetic field and material flowing into the black hole’s mouth lead the field to compress, flatten, break, and rejoin.

In the end, magnetic energy is used to slingshot hot plasma particles at near-light speed into the black hole or out into space.

Those particles may then immediately emit some kinetic energy as photons, providing an energy boost to adjacent photons.

The enigmatic black hole flares are made up of these powerful photons.

One of the latest black hole models in action. Astrophysical Journal Letters 2022, B. Ripperda et al.

This model expelled the disk of previously infalling material during flares, clearing the space surrounding the event horizon.

This cleaning up might provide astronomers a clear picture of the usually hidden activities occurring close beyond the event horizon.

Bart Ripperda, study co-lead author and a joint postdoctoral fellow at the Flatiron Institute’s Center for Computational Astrophysics (CCA) in New York City and Princeton University stated:

“The fundamental process of reconnecting magnetic field lines near the event horizon can tap the magnetic energy of the black hole’s magnetosphere to power rapid and bright flares. This is really where we’re connecting plasma physics with astrophysics.”

The new study was co-authored by Ripperda, CCA associate research scientist Alexander Philippov, Harvard University scientists Matthew Liska and Koushik Chatterjee, University of Amsterdam scientists Gibwa Musoke and Sera Markoff, Northwestern University scientist Alexander Tchekhovskoy, and University College London scientist Ziri Younsi.

Black Holes Thought to be Massive Chunks of Darkness

A black hole, as the name implies, emits no light.

So flares must come from beyond the event horizon of a black hole, which is the limit where the black hole’s gravitational pull becomes so intense that not even light can escape.

Orbiting and infalling material surrounds black holes in the form of an accretion disk, such as the one observed surrounding the M87 galaxy’s monster black hole.

This debris falls toward the event horizon, located near the black hole’s equator.

One of the latest black hole models in action. Green magnetic field lines are superimposed over a map of hot plasma in this image. The intersection of magnetic field lines going in opposing directions just beyond the event horizon creates an X-point where they crossover. This reconnection process sends some plasma particles into the black hole and others into space, which is a critical stage in the formation of black hole flares. Astrophysical Journal Letters 2022, B. Ripperda et al.

Jets of particles fly out into space at almost the speed of light from the north and south poles of some of these black holes.

Because of the physics involved, determining where flares emerge in the anatomy of a black hole is very challenging.

Black holes distort time and space while surrounded by tremendous magnetic fields, radiation fields, and swirling plasma… matter so hot that electrons separate from their atoms.

Despite the use of sophisticated computers, previous attempts could only mimic black hole systems at resolutions too low to discern the mechanism that fuels the flares.

Ripperda and his colleagues focused their efforts entirely on increasing the amount of detail in their simulations. They utilized computing time on three supercomputers: the Summit supercomputer at Oak Ridge National Laboratory in Tennessee, the Longhorn supercomputer at the University of Texas in Austin, and the Popeye supercomputer at the University of California, San Diego, run by the Flatiron Institute.

The project required millions of computation hours in total.

This processing power resulted in the highest-resolution simulation of a black hole’s surrounds yet created, with over 1,000 times the resolution of prior attempts.

The greater clarity provided the researchers with a previously unseen image of the events that lead to a black hole flare.

The process revolves on the black hole’s magnetic field, which has magnetic field lines that burst out from the event horizon of the black hole, generating the jet and linking to the accretion disk.

Previous simulations showed that material pouring into the equator of a black hole draws magnetic field lines toward the event horizon.

The dragging field lines continue to build up at the event horizon, eventually pushing back and preventing the inflow of material.

Ripperda believes that data from the newly launched James Webb Space Telescope, paired with those from the Event Horizon Telescope, will be able to establish if the process described in the new simulations is occurring and whether it affects photographs of a black hole’s shadow. We’ll have to wait and see, as Ripperda adds.

He and his colleagues are attempting to develop their simulations with more detail for the time being.

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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