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James Webb Space Telescope sees major star factory near the Milky Way’s black hole (image)

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Behold, a region of intense star formation, partially hidden by thick dust, just 300 light-years from the supermassive black hole sitting at the center of our galaxy. Better yet, the scene was imaged in all its spectacular glory by none other than the James Webb Space Telescope (JWST).

This star-forming region, known as “Sagittarius C,” exhibits 500,000 stars strewn like glitter across a blueish glowing backdrop. One of the major sights owes itself to the James Webb Space Telescope’s Near Infrared Camera (NIRCam) and involves members of a dense cluster of baby stars, or protostars, visible just left of center. Within this cluster also lies a burgeoning star that has already assembled a mass 30 times greater than our sun‘s, yet is still growing. For this star, it will be a short life. In a few million years’ time, the ultra-massive object will explode as a supernova, in contrast to stars with masses similar to our sun‘s that can survive for billions of years.

Stars form inside clumps of cold, dense molecular hydrogen that collapse in on themselves due to gravity. These clumps are laced with interstellar dust that helps keep temperatures within 10 degrees of absolute zero — absolute zero being the coldest temperature theoretically possible in our universe. In some places, the large, clumpy swathes of dust are so thick that not even the JWST’s infrared vision can penetrate them.

However, we know that deep inside these clouds are nascent stars just beginning to form. Some of those stars, such as the protocluster shown here, have grown to a stage in which their winds can blow away those dusty wombs, rendering the stars themselves visible.

Related: James Webb Space Telescope could soon solve mysteries of the Milky Way’s heart

(Image credit: NASA/ESA/CSA/STScI/Samuel Crowe (UVA))

The analysis of this new JWST image of Sagittarius C, captured by an international team studying star formation in the Galactic Center, or Milky Way’s heart, is being led by Samuel Crowe, an undergraduate student at the University of Virginia in Charlottesville.

“We are seeing lots of features here for the first time,” Crowe said in a statement, reflecting on the superior resolution and sensitivity of the 6.5-meter mirror of the JWST, which is the largest space telescope ever launched.

Among those features are outflows from the protostars that glow like fire when set against the darker, more opaque molecular hydrogen cloud. In front of that dark cloud, to the top of the image, are foreground stars; around the lower edge are sections of bright, ionized hydrogen energized by the ultraviolet light of other young, massive stars.

This ionized hydrogen had been detected previously, the team says, but the sheer size of the region — 25 light years across as seen by the JWST —was a surprise. Crowe intends to investigate this finding further, as well as track down the identity of the “needles,” or elongated slivers poking radially through the ionized gas in seemingly random directions.

Located about 26,000 light years from us, the Galactic Center is deliberately targeted by astronomers using the JWST because it is such an intense region of star formation. Indeed, in some ways, the Galactic Center shares similarities with early star-forming galaxies the JWST found to have existed just a few hundred million years after the Big Bang. Those galaxies appear brighter than expected; one possibility for why is that they are forming more massive stars than older galaxies are.

An annotated version of JWST’s image of Sagittarius C.  (Image credit: NASA/ESA/CSA/STScI/Samuel Crowe (UVA))

“The Galactic Center is the most extreme environment in our Milky Way galaxy, where current theories of star formation can be put to their most rigorous test,” said Jonathan Tan, one of Crowe’s supervisors at the University of Virginia.

In particular, astronomers are probing to see whether massive stars are more likely to form in regions of star-birth at the center of our galaxy than in the suburbs of the Milky Way’s spiral arms. Typically, star-forming nebulas give birth to the least massive stars, M-dwarfs — and with increasing stellar mass comes a drop in the birth rate. This is illustrated by the fact that there are only a handful of the most massive stars, hundreds of times the mass of our sun, existing in the Milky Way.

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This tendency to form more of the least massive stars and fewer of the most massive stars is called the stellar initial mass function (IMF), and astronomers still do not fully understand what governs it. However, the intensity of star formation in the Galactic Center may subvert the IMF, leading to the preferential formation of a greater abundance of massive stars. If this proves to be the case, then it may also apply to the earliest galaxies. If they had a higher IMF than we realized, it could explain why they are so luminous since the most massive stars shine the brightest.

“The Galactic Centre is a crowded, tumultuous place,” concluded Rubén Fedriani, a team-member of Crowe’s the Instituto Astrofísica de Andalucía in Spain, in the same press statement. “There are turbulent, magnetized gas clouds that are forming stars, which then impact the surrounding gas with their outflowing winds, jets and radiation. Webb has provided us with a ton of data on this extreme environment, and we are just starting to dig into it.”

 

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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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