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Astronomers Just saw the Most Powerful Gamma-ray Burst Ever Recorded

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Gamma-ray bursts (GRBs) are one of the most mysterious transient phenomena facing astronomers today. These incredibly energetic bursts are the most powerful electromagnetic events observed since the Big Bang and can last from a few milliseconds to many hours. Whereas longer bursts are thought to occur during supernovae, when massive stars undergo gravitational collapse and shed their outer layer to become black holes, shorter events have also been recorded when massive binary objects (black holes and neutron stars) merge.

These bursts are characterized by an initial flash of gamma rays and a longer-lived “afterglow” typically emitted in X-ray, ultraviolet, radio, and other longer wavelengths. In the early-morning hours on October 14th, 2022, two independent teams of astronomers using the Gemini South telescope observed the aftermath of a GRB designated GRB221009A. Located 2.4 billion light-years away in the Sagitta constellation, this event was perhaps the closes and most powerful explosion ever recorded and was likely triggered by a supernova that gave birth to a black hole.

 

Longer-duration GRBs occur when massive stars go supernova, producing a remnant black hole and blowing off their outer layers. The force of this explosion creates powerful jets as ejected material is accelerated to nearly the speed of light, pushing through debris and emitting X-rays and gamma-rays as they reach further into space. If these jets travel in the general direction of Earth, astronomers will observe them as bright flashes of X-rays and gamma-rays. Using data from some of the most powerful telescopes on Earth and in space, astronomers were able to make unprecedented observations of a nearby GRB.

GRB221009A was first detected on the morning of October 9th, 2022, by X-ray and gamma-ray space telescopes – including NASA’s Fermi Gamma-ray Space Telescope, Neil Gehrels Swift Observatory, and the Wind spacecraft. Almost immediately after, observatories worldwide raced to conduct follow-up observations and determine what resulted. Using the Gemini South telescope (operated by NOIRLab), two independent teams made rapid Target of Opportunity (ToO) observations of the powerful event’s afterglow.

The teams were led by Brendan O’Connor, a graduate observational astronomer with the University of Maryland and George Washington University, and Jillian Rastinejad, a Ph.D. student at Northwestern University’s Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA). The two teams obtained the earliest-possible observations of the afterglow mere minutes apart using the Gemini South’s FLAMINGOS-2 near-infrared imaging instrument and the Gemini Multi-Object Spectrograph (GMOS), respectively.

As Rastinejad explained in a recent NOIRLab’s press release, their combined datasets produced an image of what could be the brightest GRB ever observed:

“In our research group, we’ve been referring to this burst as the ‘BOAT,’ or Brightest Of All Time, because when you look at the thousands of bursts gamma-ray telescopes have been detecting since the 1990s, this one stands apart. Gemini’s sensitivity and diverse instrument suite will help us to observe GRB221009A’s optical counterparts to much later times than most ground-based telescopes can observe. This will help us understand what made this gamma-ray burst so uniquely bright and energetic.

The speed with which the teams made their observations is a testament to the Gemini Observatory’s infrastructure and data-reduction software – including the Fast Initial Reduction Engine (FIRE) and Data Reduction for Astronomy from Gemini Observatory North and South (DRAGONS) platforms. Shortly after, the NASA Gamma-ray Coordinates Network began filling up with reports from observatories worldwide. Based on the available data, scientists believe that the GRB was the result of a collapse of a star many times the mass of our Sun that gave birth to a black hole.

Artistic representation of two merging neutron stars. Credit: Dana Berry, SkyWorks Digital, Inc.

What’s more, the data from this event may help resolve an ongoing mystery regarding GRBs. Whereas most gamma-ray bursts have been observed in distant galaxies, some appear as lonely flashes from intergalactic space. This has raised questions about the true origins and distances of GRBs, with many astronomers theorizing that certain short bursts originate in the intergalactic medium (IGM). However, these results suggest that short GRBs may have been more common in the past than expected.

The research teams came to this conclusion after consulting data on the 120 short GRBs observed by the two main instruments aboard NASA’s Neil Gehrels Swift Observatory – the Burst Alert Telescope (BAT) and the Swift X-ray Telescope, which detect bursts and examine the X-ray afterglow. They paired this with additional afterglow studies made with the Lowell Discovery Telescope (LDT), which found that 43 of the short GRBs were not associated with any known galaxy and appeared in the comparatively empty space between galaxies. As O’Connor explained in a University of Maryland news story:

“Many short GRBs are found in bright galaxies relatively close to us, but some of them appear to have no corresponding galactic home. By pinpointing where the short GRBs originate, we were able to comb through troves of data from observatories like the twin Gemini telescopes to find the faint glow of galaxies that were simply too distant to be recognized before.”

These findings could also have implications for our understanding of the early Universe. In recent years, astronomers have found evidence that precious metals like gold and platinum may have come from neutron star mergers that happened billions of years ago. If these events were more common in the past, it could mean that the Universe was seeded with precious metals earlier than expected. In the meantime, the energetic nature of this event makes it a once-in-a-lifetime opportunity for astronomers. As O’Conner explained:

“The exceptionally long GRB 221009A is the brightest GRB ever recorded and its afterglow is smashing all records at all wavelengths. Because this burst is so bright and also nearby, we think this is a once-in-a-century opportunity to address some of the most fundamental questions regarding these explosions, from the formation of black holes to tests of dark matter models.

Artist’s impression of two neutron stars colliding, known as a “kilonova” event. Credits: Elizabeth Wheatley (STScI)

Because of its relative proximity to Earth, this event is also a unique opportunity to study the origin of the elements heavier than iron (which form in the interiors of stars) and whether they come from neutron-star mergers alone or collapsing stars as well. Last, but not least, this event also led to disturbances in the Earth’s ionosphere that affected long-wave radio transmissions and produced very high-energy (18 tera-electron-volt) photons detected by the Chinese Large High Altitude Air Shower Observatory.

How these photons survived the 2.4 billion-year journey to Earth is a mystery. Therefore, this data could reveal new insight into how the laws of physics behave in extreme circumstances and allow astrophysics to predict the effect that future GRBs could have on Earth.

The International Gemini Observatory consists of the Gemini North Telescope in Hawaii and the Gemini South Telescope in Chile, which are operated by the National Optical-Infrared Astronomy Research Laboratory (NOIRLab) – part of the National Science Foundation’s (NSF). The papers that describe the two teams’ findings recently appeared in the Monthly Notices of the Royal Astronomical Society and The Astrophysical Journal.

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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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