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Gravitational waves reveal merger between black hole and mystery 'mass gap' object – CTV News

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A mysterious astronomical object merged with a black hole 780 million light-years away and created gravitational waves that could be detected on Earth. The object exists inside what scientists call the “mass gap,” a range between the heaviest known neutron star and the lightest known black hole. And it could change how astronomers understand black holes.

In August 2019, astronomers using gravitational wave detectors in the US and Italy detected ripples in space and time, a gravitational wave event they dubbed GW190814. Given the fact that this occurred so far from Earth, the event occurred 780 million years ago, but the gravitational waves are just now reaching us.

The merger occurred between an object that was 2.6 times the mass of our sun with a black hole that was 23 times the mass of our sun. This large difference in the sizes of both objects, differing by a factor of nine, makes it the most extreme mass ratio for a gravitational wave event known to date.

The merger led to a black hole about 25 times the mass of the sun. Some of the mass was blasted out as gravitational waves.

The Laser Interferometer Gravitational-Wave Observatory, or LIGO, and Virgo were used to detect the event. The National Science Foundation’s LIGO includes two detectors — one in Livingston, Louisiana, and another in Hanford, Washington. The Virgo detector is located in Cascina, Italy.

Black holes are created when massive stars die and collapse. Stars that are less massive explode in a supernova. The remnant of this outburst is a neutron star, which is small but very dense.

Currently, the heaviest known neutron star is 2.5 times the mass of our sun and the lightest black hole is five times the mass of our sun. In between is the “mass gap” into which this object fits.

An international team of astronomers were involved in the study, which published Tuesday in The Astrophysical Journal Letters.

“We’ve been waiting decades to solve this mystery,” said Vicky Kalogera, study coauthor and Daniel I. Linzer distinguished university professor of physics and astronomy at Northwestern University, in a statement.

“Mergers of a mixed nature — black holes and neutron stars — have been predicted for decades, but this compact object in the mass gap is a complete surprise. We are really pushing our knowledge of low-mass compact objects,” Kalogera said.

“Even though we can’t classify the object with conviction, we have seen either the heaviest known neutron star or the lightest known black hole. Either way, it breaks a record,” said Kalogera, who is also director of Northwestern’s Center for Interdisciplinary Exploration and Research in Astrophysics (CIERA).

A DIFFERENT KIND OF DETECTION

When LIGO and Virgo scientists detected this event, they sent out an immediate alert across the astronomy community to allow for follow-up by Earth and space-based telescopes. The hope is to find light waves also caused by the event.

This has only been seen once during a gravitational wave event, known as GW170817, which occurred in August 2017. It was the result of two neutron stars colliding and releasing light, gravitational waves and even creating elements like gold. Neutron star collisions are fiery, energetic and messy, releasing matter in all directions, and light is a by-product.

Mergers between two black holes, however, aren’t believed to create light.

When telescopes followed up on the August 2019 event, they didn’t pick up any signals of light waves. Scientists believed this is due to the distance of the event, which was six times farther away than the 2017 merger. If it was in fact a merger between two black holes, no light would be produced. And if it was a neutron star, the black hole was so much larger that it may have simply swallowed it.

“I think of Pac-Man eating a little dot,” Kalogera said. “When the masses are highly asymmetric, the smaller compact object can be eaten by the black hole in one bite.”

The detection challenges current theoretical models of how stars die as well as how they pair up in binary systems. Binary systems, like two stars orbiting each other, occur when the two objects are close enough for gravity to create a central orbit.

“The mass gap has been an interesting puzzle for decades, and now we’ve detected an object that fits just inside it,” said Pedro Marronetti, program director for gravitational physics at the National Science Foundation, in a statement.

“That cannot be explained without defying our understanding of extremely dense matter or what we know about the evolution of stars,” Marronetti said. “This observation is yet another example of the transformative potential of the field of gravitational-wave astronomy, which brings novel insights to light with every new detection.”

AN ASYMMETRIC BINARY SYSTEM

The researchers said they didn’t expect to find a binary system including two objects with such different masses, but now they know these are actually being created somewhere in the universe. Next, they have the challenge of trying to figure out what exactly they are and how they work, according to Alberto Vecchio, study co-author and director of the Institute for Gravitational Wave Astronomy.

Though the opportunity to study this event in detail has passed, this discovery will change the way astronomers understand and study neutron stars and black holes going forward.

Future detections of similar events could help astronomers determine if there are more objects that exist in the mass gap.

“This is the first glimpse of what could be a whole new population of compact binary objects,” said study coauthor Charlie Hoy, a member of the LIGO Scientific Collaboration and a graduate student at Cardiff University, in a statement.

“What is really exciting is that this is just the start,” Hoy said. “As the detectors get more and more sensitive, we will observe even more of these signals, and we will be able to pinpoint the populations of neutron stars and black holes in the universe.”

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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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