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How to Create a Black Hole Out of Thin Air – The New York Times

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Black holes were thought to arise from the collapse of dead stars. But a Webb telescope image showing the early universe hints at an alternative pathway.

How many ways are there to leave this universe?

Perhaps the best known exit entails the death of a star. In 1939 the physicist J. Robert Oppenheimer and his student Harlan Snyder, of the University of California, Berkeley, predicted that when a sufficiently massive star runs out of thermonuclear fuel, collapses inward and keeps collapsing forever, shrink-wrapping space, time and light around itself in what today is called a black hole.

But it turns out that a dead star might not be needed to make a black hole. Instead, at least in the early universe, giant clouds of primordial gas may have collapsed directly into black holes, bypassing millions of years spent in stardom.

That is the tentative conclusion recently reached by a group of astronomers studying UHZ-1, a speck of light dating from not long after the Big Bang. In fact, UHZ-1 is (or was) a powerful quasar that spat fire and X-rays from a monstrous black hole 13.2 billion years ago, when the universe was not quite 500 million years young.

That is unusually soon, cosmically speaking, for so massive a black hole to have come into being through stellar collapses and mergers. Priyamvada Natarajan, an astronomer at Yale and the lead author of a paper published in the Astrophysical Journal Letters, and her colleagues, contend that in UHZ-1 they have discovered a new celestial species, which they call an overmassive black hole galaxy, or O.B.G. In essence, an O.B.G. is a young galaxy anchored by a black hole that became too big too fast.

The discovery of this precocious quasar could help astronomers solve a related puzzle that has tantalized them for decades. Nearly every galaxy visible in the modern universe seems to harbor at its center a supermassive black hole millions of billions of times as massive as the sun. Where did those monsters come from? Could ordinary black holes have grown so large so fast?

Dr. Natarajan and her colleagues propose that UHZ-1, and so perhaps many supermassive black holes, began as primordial clouds. These clouds could have collapsed into kernels that were precociously heavy — and were sufficient to jump-start the growth of overmassive black hole galaxies. They are another reminder that the universe we see is governed by the invisible geometry of darkness.

“As the first O.B.G. candidate, UHZ-1 provides compelling evidence for the formation of heavy initial seeds from direct collapse in the early universe,” Dr. Natarajan and her colleagues wrote. In an email, she added: “Nature does seem to make BH seeds many ways, beyond just stellar death!”

Daniel Holz, a theorist at the University of Chicago who studies black holes said: “Priya has found an extremely exciting black hole, if true.”

He added, “It is simply too big too early. It’s like looking in at a kindergarten classroom and there among all the 5-year-olds is one that is 150 pounds and/or six feet tall.”

According to the story that astronomers have been telling themselves about the evolution of the universe, the first stars condensed out of clouds of hydrogen and helium left over from the Big Bang. They burned hot and fast, quickly exploding and collapsing into black holes 10 to 100 times as massive as the sun.

Over eons, successive generations of stars were formed from the ashes of previous stars, enriching the chemistry of the cosmos. And the black holes left over from their deaths kept merging and growing somehow, into the supermassive black holes at the centers of galaxies.

The James Webb Space Telescope, launched two years ago this Christmas, was designed to test this idea. It possesses the biggest mirror in space, 21 feet in diameter. More important, it was designed to record infrared wavelengths from the light of the most distant and therefore earliest stars in the universe.

But as soon as the new telescope was trained on the sky, it caught sight of new galaxies so massive and bright that they defied cosmologists’ expectations. Arguments have raged for the last couple of years about whether these observations in fact threaten a longstanding model of the cosmos. The model describes the universe as composed of a trace of visible matter, astounding amounts of “dark matter,” which provides the gravity to hold galaxies together, and “dark energy,” pushing these galaxies apart.

The discovery of UHZ-1 represents an inflection point in these debates. In preparation for a future observation by the James Webb Space Telescope of a massive cluster of galaxies in the constellation Sculptor, Dr. Natarajan’s team asked for time on NASA’s Chandra X-ray Observatory. The cluster’s mass acts as a gravitational lens, magnifying objects far behind it in space and time. The researchers hoped to get a glimpse in X-rays of whatever the lens might bring into view.

What they found was a quasar powered by a supermassive black hole about 40 million times as massive as the sun. Further observations by the Webb telescope confirmed that it was 13.2 billion light-years away. (The Sculptor cluster is about 3.5 billion light-years away.) It was the most distant and earliest quasar yet found in the universe.

“We needed Webb to find this remarkably distant galaxy, and Chandra to find its supermassive black hole,” Akos Bogdan of the Center for Astrophysics Harvard & Smithsonian said in a news release. “We also took advantage of a cosmic magnifying glass that boosted the amount of light we detected.”

The results indicate that supermassive black holes existed as early as 470 million years after the Big Bang. That isn’t enough time to allow the black holes created by the first generation of stars — starting out at 10 to 100 solar masses — to grow so big.

Was there another way to make even bigger black holes? In 2017 Dr. Natarajan suggested that collapsing clouds of primordial gas could have birthed black holes more than 10,000 times as massive as the sun.

“You can then imagine one of these subsequently growing into this young, precociously large black hole,” Dr. Holz said. As a result, he noted, “at every subsequent time in the universe’s history there will always be some surprisingly large black holes.”

Dr. Natarajan said, “The fact that these start out in life overmassive implies that they will likely eventually evolve into supermassive black holes.” But no one knows how that works. Black holes make up 10 percent of the mass in the early quasar UHZ-1, whereas they compose less than one one-thousandth of a percent of the mass of modern-day galaxies like the giant Messier 87, whose black hole weighed in at 6.5 billion solar masses when its picture was taken by the Event Horizon Telescope in 2019.

That suggests that complicated environmental feedback effects dominate the growth and evolution of these galaxies and their black holes, causing their mass in stars and gas to bulk up.

“So in effect these extremely early O.B.G.s are really telegraphing much more information about, and illuminating, seeding physics rather than later growth and evolution,” Dr. Natarajan said. She added: “Though they have important implications.”.

Dr. Holz said, “It would certainly be cool if it turns out to be what’s happening, but I’m genuinely agnostic.” He added, “It’s going to be a fascinating story no matter how we solve the mystery of early big black holes.”

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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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