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A New Study of Lifeless Suns Finds How Life on Earth May Not Exist With no Them – haveeruonline

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Carbon. You could possibly not believe about it quite considerably, but you wouldn’t be alive with out it. It is the principal ingredient in organic compounds identified in all dwelling organisms on Earth, but just wherever carbon will come from has been a matter of some discussion.

Now, new analysis has located that the primary resource of carbon in the Milky Way is white dwarf stars – the dead cores of stars that ended up after a great deal like our Sun.

It is properly recognized that elements heavier than hydrogen and helium are cast by stars across the Universe. The fusion of elements in the cores of stars can construct aspects as heavy as iron by way of a process named stellar nucleosynthesis even heavier aspects are produced via processes this kind of as the neutron seize found in enormous supernovae.

Carbon is shaped by using the triple-alpha process, in which a few helium nuclei fuse jointly to kind carbon, a procedure that requires spot towards the finish of a star’s lifespan.

But it was unclear to astronomers regardless of whether the abundance of carbon in our galaxy was mostly the outcome of Sunlight-sized stars shedding their skins as they quietly collapsed into white dwarfs, or if it was blasted out by considerably additional massive stars as they went supernova.

A staff of astronomers led by Paolo Marigo of the University of Padova in Italy went seeking for answers in open up star clusters – teams of up to countless numbers of stars that are all additional or considerably less the very same age, formed in the same molecular cloud.

In five molecular clouds, the staff determined the white dwarfs, using observations obtained by the W. M. Keck Observatory in Hawaii in 2018. These observations shipped the star spectra – ‘fingerprints’ of light that can be decoded to expose info about the star, this kind of as temperature (and as a result age), chemical composition, and surface gravity (and consequently mass).

“From the evaluation of the noticed Keck spectra, it was achievable to evaluate the masses of the white dwarfs. Employing the principle of stellar evolution, we ended up equipped to trace back again to the progenitor stars and derive their masses at start,” spelled out astrophysicist Enrico Ramirez-Ruiz of the University of California Santa Cruz.

The mass of a dead star is recognised to be linked to that of its progenitor. It tends to make sense – the a lot more large a white dwarf, the far more large the progenitor star that generated it. These masses usually are not exactly the exact same, although, considering the fact that the progenitor star ejects so significantly content into area. This partnership concerning the two masses of the white dwarf is regarded as the preliminary-closing mass relation.

In white dwarfs, the mass relation can be calculated if you have a white dwarf’s spectrum. As useless stars, they are no longer fusing nuclei, and are thus cooling any heat a white dwarf retains is residual, and will gradually radiate out into area in excess of billions of decades. If we know its mass, temperature and chemical composition, we can compute the amount of this cooling. In change, this permits astronomers to determine the white dwarf’s age – how prolonged given that core collapse.

This is where the open up clusters occur into the photograph. Due to the fact we know how outdated the clusters are, we can subtract the time due to the fact core collapse from the age of the cluster to find out how aged the star was when it died – and this information can be employed to work out the preliminary mass of the progenitor star.

But when the group utilized it to some of their white dwarfs – exclusively, all those with a progenitor mass bigger than about 1.5 situations the mass of the Solar – they seen a little something actually peculiar. The masses of the white dwarfs were higher than envisioned for the masses of their progenitors, what the group calls an initial-last mass relation kink.

“Our analyze interprets this kink in the original-closing mass romantic relationship as the signature of the synthesis of carbon produced by minimal-mass stars in the Milky Way,” Marigo said.

The staff thinks that the event usually takes place in white dwarf progenitor stars in the direction of the finishes of their lifespans. They fuse helium into carbon, deep in their cores. Then this carbon is transported to the floor, exactly where it is blown off into house in comparatively light stellar winds. Simply because the procedure happens so little by little, the star has time to acquire mass in the core. It is this additional enormous core that collapses into a heavier-than-expected white dwarf.

Generally, this occurs in stars of much more than about 2 solar masses, but it can be not seen in stars of fewer than 1.5 photo voltaic masses, which destinations a really excellent lower restrict on the mass of carbon-spewing stars. Importantly, a glance at equivalent stars in other galaxies assists us improved understand the timing of dying stars dusting the Milky Way with carbon, producing the progenitors of white dwarfs the most very likely supply.

This could also assistance us to fully grasp what is going on in distant galaxies, where we are not able to make out personal stars. A carbon signature in the combination light can convey to us about distant white dwarf populations.

And the study will also far better help us have an understanding of how carbon will get seeded in the course of the Milky Way – which, in convert, could have implications for the search for extraterrestrial lifetime.

The analysis has been revealed in Nature Astronomy.

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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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