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Astronomers solve mystery of the vanishing planet with new NASA data – CNET

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Fomalhaut b… smashed to smithereens? 


NASA/ESA/A. Gaspar/G. Rieke/University of Arizona

Fomalhaut b is a ghost with a complicated history. 

In 2004, Paul Kalas, an astronomer at the University of California, Berkeley, made a surprising find. Using NASA’s powerful Hubble telescope, Kalas and his colleagues saw direct evidence of a planet moving around the star Fomalhaut, which is about 25 light-years away from Earth. They published their findings in the journal Science, describing the the massive, young planet as three times the mass of Jupiter. 

It was, and still is, a rare feat for astronomers to see a planet in optical light from outside our solar system directly — usually they are obscured by the light from their stars and so far away they don’t blink at us like a star might. So planet hunters use indirect methods to detect exoplanets like seeing how much a star wobbles due to the gravitational effects of a planet. But in 2004, Kalas used Hubble to look at Fomalhaut and noticed a speckle of light in the images. It was one of the first times an exoplanet had ever been imaged. 

“Fomalhaut b is one of the most intriguing discoveries ever made with the Hubble Space Telescope,” Kalas says.  

But Fomalhaut b vanished. Disappeared. New research, published in the journal Proceedings of the National Academy of Sciences on Monday, reveals Fomalhaut b may not be a planet at all. Instead, it may be the lingering light from a giant collision between two huge asteroids. 

As luck would have it

An animation simulating the collision of two huge asteroids. The ring of debris surrounding star Fomalhaut is displayed in yellow, while inset, a simulation shows the fading signal from 2004 to 2015. 


NASA/ESA/A. Gaspar/G. Rieke/University of Arizona

The notion Fomalhaut b may not be an exoplanet has been raised since its discovery by Kalas in 2004. Although visible in optical light, researchers couldn’t find the infrared signature a planet that size should create. As a result, Fomalhaut b’s true identity has remained enigmatic. 

Alternative hypotheses have been suggested in the past, including in Kalas’s original 2008 paper. There have been suggestions Fomalhaut b is a dust-cloud or material captured from the huge disk of debris surrounding Fomalhaut, the star.

“Astronomers have struggled categorizing Fomalhaut b,” says András Gáspár, an astronomer at the University of Arizona and co-author on the new paper. “That alone makes it an interesting object.”

Gáspár is part of the science team at the University of Arizona which has access to NASA’s James Webb Space Telescope, a Hubble successor scheduled to launch in 2018 but plagued with development delays. The team has already scheduled in almost 50 days of observation time for Fomalhaut b when James Webb gets off the ground in 2021. 

In preparation, Gáspár downloaded archival Hubble telescope data and started looking for things other researchers may have missed in a couple of unpublished datasets. 

He noticed something weird with Fomalhaut b: Its light was fading. 

“That’s how it started, pure luck,” he says. 

Gáspár and colleague George Rieke studied the Hubble data and noticed Fomalhaut b was vanishing over time. From a pinprick of light in 2004 data, Fomalhaut b became a ghost of a planet, the light that appeared in Hubble data began to dissipate and expand before disappearing in 2014.

The archival Hubble data, from 2014, led Gáspár to investigate further.

Gáspár has modelled debris disks and collisions in the past and investigated the fading signal with computer modelling. Plugging the collision of two gargantuan pre-planets, around 125 miles wide (200 kilometers), into their system, the team discovered the characteristics seen by Hubble matched up neatly.

“Our modeling shows the observed characteristics agree with a model of an expanding dust cloud produced in a massive collision,” says Gáspár. The model accounts for all of the strangeness seen with Fomalhaut b during its observation history, from Kalas’s discovery to some of the last observations seven years ago.

Collide-o-scope

Gáspár and Rieke aren’t the first to propose Fomalhaut b is not a planet. Previous analyses of the Hubble data suggested Fomalhaut b was just an unlucky dual wipeout. But the latest study is the first to show a model demonstrating two big space rocks (a little smaller than the “dwarf planet” Hygiea) smashing into each other as a definitive explanation. And that’s pretty phenomenal: When Kalas pointed the Hubble Space Telescope at Fomalhaut in 2004, he saw something incredibly rare.

Kalas says a collision that could cause such a dust cloud would only happen “once every 100,000 years” and the resulting cloud would linger for just a decade. Such odds have seem him wrestle with his own good fortune.

“Was I really the luckiest astronomer in the world when I pointed the Hubble Space Telescope at Fomalhaut back in 2004?” he asks. “If I had tried just a few years earlier or a few years later, I never would have discovered it.”

Gáspár and Rieke’s observations suggest he may be even luckier — with their calculations showing such a collision might occur once every 200,000 years. That would mean the collisions have only occurred twice in the history of humanity. Gáspár says it’s “genuinely exciting” to be able to measure and analyze such an event. 

Is there still hope for the planet hypothesis? It seems less and less likely. Planets don’t just vanish. Gáspár doubts we will ever see this object again now that it has disappeared. 

“As far as I am concerned, we can put a period at the end of the sentence describing Fomalhaut b,” he says.

But our understanding of the cosmos is constantly evolving with new observations. Indeed, the latest study shows the scientific method in action: Discoveries are scrutinized and, with new evidence, hypotheses change. 

And Kalas will continue to examine Fomalhaut, a system he’s been studying since he was a student in the 1990s. He’s asked for some time using the Hubble Space Telescope to re-observe Fomalhaut in the next year. This, he says, could validate the collision hypothesis.

The mystery of Fomalhaut b seems mostly settled, but now researchers await the launch of the James Webb Telescope in 2021. Kalas says the telescope will “probably give the next big leap in understanding the planetary system around Fomalhaut.” Imaging instruments on that space telescope may discover bona fide planets and Gáspár notes any new discoveries will contribute to our understanding of how planetary systems — like our solar system — evolve over time.

“The Fomalhaut system, with its massive planetary debris disk, still holds many mysteries to uncover,” he says.

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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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