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New study finds the Universe has less dark energy than previously theorized

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The makeup and the growth of the Universe have never been clearer — or as confusing — as they’ve been revealed to be in a massive new survey of the markers astronomers use to measure the cosmos.

A new analysis called Pantheon+ has narrowed down the uncertainty in the expansion and makeup of the Universe. To do this, Pantheon+ builds on two long-standing astronomical projects — one called Pantheon, combining observations of 1,550 supernovae reaching back 10 billion years; and another called SH0ES, which measures relatively close pulsing stars known as Cepheids within 10 million light years.

The Pantheon+ analysis of the makeup and expansion of the Universe published recently in The Astrophysical Journal finds that 66.2 percent of the Universe is made up of dark energy, the mysterious accelerator driving the Universe’s speeding expansion, slightly less than past estimates of about 68 percent.

Only 33.8 percent of the Universe is matter — and the vast majority of that is impossible-to-observe dark matter, whose existence astronomers can only infer from galactic-scale gravitational effects. At the accepted rate of 85 percent dark matter to 15 percent normal (baryonic) matter, that means just slightly less than 5 percent of the mass of the Universe is the stuff we can see around us.

Pantheon+ was also able to measure the Universe’s expansion to within 1.3 percent uncertainty, close enough that it is now undeniable that the early Universe and the current Universe don’t expand at the same pace.

Speaking with Inverse, lead author Dillon Brout, a NASA Einstein fellow at the Center for Astrophysics | Harvard-Smithsonian, says that this degree of precision means that instead of being limited by the data for measuring the growth of the Universe, “we’re approaching the limit where we’re limited by the uncertainties of our method.”

WHAT’S NEW — Pantheon+ offers as precise a measurement of dark energy, dark matter, and baryonic matter as can currently be assembled.

And “assembled” is the right word — this work combines analysis from the original Pantheon, which measured dark matter, and the Supernova H0 for the Equation of State (SH0ES), which measures the Hubble constant at which the Universe expands.

Pantheon+ synthesizes two decades of data from different telescopes and astronomers into a single analysis; it represents “an all-star sample,” Brout explains. And this is the biggest set of exploding stars that have been put together — over 1500, half again as many as an earlier version that focused just on the supernovae.

But Brout notes that’s about all that can be gained with current equipment. The limiting factor is time. “We get about one supernova per year that helps us measure the Hubble constant, and we’ve got 42 of them now. So we’re going to have to wait a while just to double our data set,” he says.

The cosmic microwave background is one of the best ways to understand the early universe. Print Collector/Hulton Archive/Getty Images

WHY IT MATTERS — Surveys like Pantheon+ allow astronomers to cross-check their results across different methods and different targets. Some components measure Cepheids, relatively nearby stars whose brightness waxes and wanes regularly; others measure supernovae who outshone galaxies up to 10 billion years ago.

For the time being, this is about as accurate as these kinds of measurements can get. “A lot of people will think ‘of course, you have to use James Webb,’” says Brout, “and the answer to that is ‘yes’ — but it’s not immediately clear how much it’s going to help us.” The James Webb Space Telescope will let astronomers look at the ways stellar dust and observations in different wavelengths impact observations of the anchors that hold their measurements in place.

The increasing accuracy of this analysis has also increased one of the biggest problems in cosmology. Pantheon+ has narrowed down the speed at which the Universe is expanding to 73.4 kilometers per second per megaparsec — give or take 1.3 percent. This means that, locally, space is getting bigger at about 164,000 miles per hour.

But that’s just here and, more importantly, now. Measurements of the cosmic microwave background show that in its earliest days, the Universe was definitely expanding slower, about 67 kilometers per second per megaparsec. As surveys like Pantheon+ get more accurate, it gets clearer and clearer that this discrepancy — the Hubble tension — can’t just be explained away by the difficulty of getting clear observations.

The Universe’s expansion has undeniably sped up, but it’s not quite clear why.

WHAT’S NEXT — As an overview of the field, Brout notes Pantheon+ is a way of capturing the state of the art right before an enormous transformation. Over the next two years, the Vera Rubin Observatory in Chile will come on line, and “the game is going to kind of change in the future.”

While work measuring dark matter, dark energy, and the expansion of the cosmos have been built on many different observations with many different tools, “going forward we have these big, billion-dollar telescopes that are collecting really enormous samples on their own.”

How enormous? The Rubin Observatory expects to find over a million of the right kind of ancient supernovae in the next dozen years – a thousand times more than what Pantheon+ collates.

The scale of the teams working on this data will change, too: “these are going to be huge collaborations with hundreds of people and they’re going to nail a lot of these things down.” But for now, “before these really big giant telescopes turn on,” Brout hopes Pantheon+ can be the apex of an era.

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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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