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Four revelations from the Webb telescope about distant galaxies – Nature.com

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Astronomers found these two distant galaxies in the same small part of the sky. They estimate that the one on the right is from 300 million years after the Big Bang.Credit: JWST GLASS Survey NASA/CSA/ESA/STScI; Pascal Oesch/University of Geneva

NASA built its state-of-the-art James Webb Space Telescope to peer into the distant Universe and back towards the dawn of time — and it’s already doing so spectacularly. In the two weeks since Webb’s first science images and data became available for astronomers to work with, they have reported a flood of preliminary discoveries, including multiple contenders for what could be the most distant galaxy ever seen.

Webb’s images reveal a wealth of galaxies glimmering in the distant cosmos, appearing as they did just a few hundred million years after the Big Bang 13.8 billion years ago. The telescope’s astonishingly sharp pictures have shattered astronomers’ preconceptions about the early Universe.

“We had in mind an idea of what galaxies at these [distances] would look like, and how much detail we’d be able to see, but I think the reality is just kind of blowing our mind,” says Jeyhan Kartaltepe, an astronomer at the Rochester Institute of Technology in New York.

Here are some things astronomers are learning from Webb’s first observations.

There are an awful lot of galaxies way out there.

Because Webb detects infrared light, and because the expansion of the cosmos stretches light to redder wavelengths, the telescope is well suited to spotting galaxies that formed early in the Universe’s history. In its first observing programmes, which kicked off in June, Webb discovered many distant galaxies that lie beyond the reach of other observatories, such as the Hubble Space Telescope.

“It suggests what many of us have been arguing, that there are galaxies out there beyond what we saw with Hubble,” says Richard Ellis, an astronomer at University College London.

The era of early galaxies began at ‘cosmic dawn’, starting perhaps around 250 million years after the Big Bang, when the first stars formed and lit up the Universe. Later generations of stars amassed themselves into galaxies, which are the faint red blobs that Webb is beginning to discover.

Many of the Webb images are peppered with never-before-seen galaxies in the distant Universe. “There’s hardly any empty space that doesn’t have something,” Kartaltepe says.

One study combed through data from many of the distant galaxy fields Webb has observed so far, to analyse the rate at which stars formed in the early Universe. It found 44 previously unknown galaxies stretching back to within 300 million years of the Big Bang. Combined with 11 previously known galaxies, the findings show that there was a significant population of galaxies forming stars in the early Universe1. The results “re-affirm the enormous potential of forthcoming larger [Webb] programmes to transform our understanding of the young Universe,” wrote the team, led by Callum Donnan of the University of Edinburgh, UK, in a paper on the arXiv preprint server.

Many galaxies are competing for the ‘most distant’ title.

Perhaps the highest-profile rush is the stampede of research teams vying to identify the most distant galaxy in the Webb data. A number of candidates have been spotted that will need to be confirmed through further studies, but all of them would break Hubble’s record for the most-distant galaxy, which dates to around 400 million years after the Big Bang2,3.

Maisie’s Galaxy: Astronomer Steven Finkelstein nicknamed this distant galaxy after his daughter. He estimates that it is from 280 million years after the Big Bang.Credit: Steven Finkelstein (UT Austin), Micaela Bagley (UT Austin), Casey Papovich (Texas A&M) and the CEERS Team

One contender popped up in a Webb survey called GLASS that included another, slightly less faraway galaxy in the same image4. “The fact that we found these two bright galaxies, that was really a surprise,” says Marco Castellano, an astronomer at the National Institute for Astrophysics in Rome. He and his colleagues weren’t expecting to find any galaxies that distant in this small part of the sky. A second team also independently spotted the two galaxies5.

Astronomers characterize the distance of galaxies with a measure known as redshift, which quantifies how much a galaxy’s light has been shifted to redder wavelengths; the higher the redshift, the more distant the galaxy. The GLASS candidate has a redshift of about 13. But on 25 and 26 July, days after astronomers reported the GLASS galaxies, papers claiming even higher redshifts flooded the arXiv preprint server. “This is just the beginning of the beginning,” says Rohan Naidu, an astronomer at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts.

One candidate, at a redshift of 14, emerged in a survey called CEERS, one of Webb’s highest-profile early projects. The CEERS principal investigator, Steven Finkelstein at the University of Texas at Austin, nicknamed the object Maisie’s Galaxy, after his daughter6. Another study looked at the very first deep-field image from Webb, released by US President Joe Biden on 11 July, and found two potential galaxies at a redshift of 16, which would place them just 250 million years after the Big Bang7. And other arXiv papers speculate on other candidates, even out to redshifts of 208.

Some early galaxies are surprisingly complex.

Webb’s distant galaxies are also turning out to have more structure than astronomers had expected.

One study of Webb’s first deep-field image found a surprisingly large number of distant galaxies that are shaped like disks9. Using Hubble, astronomers had concluded that distant galaxies are more irregularly shaped than nearby ones, which, like the Milky Way, often display regular forms such as disks. The theory was that early galaxies were more often distorted by interactions with neighbouring galaxies. But the Webb observations suggest there are up to 10 times as many distant disk-shaped galaxies as previously thought.

US President Joe Biden released this deep-field image on 11 July — the first scientific view from Webb revealed publicly.Credit: NASA, ESA, CSA, and STScI

“With the resolution of James Webb, we are able to see that galaxies have disks way earlier than we thought they did,” says Allison Kirkpatrick, an astronomer at the University of Kansas in Lawrence. That’s a problem, she says, because it contradicts earlier theories of galaxy evolution. “We’re going to have to figure that out.”

Another preprint manuscript suggests that massive galaxies formed earlier in the Universe than previously known. A team led by Ivo Labbé of the Swinburne University of Technology in Melbourne, Australia, reports finding seven massive galaxies in the CEERS field, with redshifts between 7 and 1010. “We infer that the central regions of at least some massive galaxies were already largely in place 500 million years after the Big Bang, and that massive galaxy formation began extremely early in the history of the Universe,” the scientists wrote.

And studies of galactic chemistry also show a rich and complicated picture emerging from the Webb data. One analysis of the first deep-field image examined the light emitted by galaxies at a redshift of 5 or greater. (Spectral lines that appear at various wavelengths of light correlate with the chemical elements composing the galaxies.) It found a surprising richness of elements such as oxygen11. Astronomers had thought that the process of chemical enrichment — in which stars fuse hydrogen and helium to form heavier elements — took a while, but the finding that it is under way in early galaxies “will make us rethink the speed at which star formation occurs”, Kirkpatrick says.

Closer galaxies are smaller than expected.

The surprises from Webb continue even a little later in the Universe’s evolution. One study looked at Webb’s observations of ‘cosmic noon’, the period approximately 3 billion years after the Big Bang. This is when star formation peaked in the Universe, and the most light was created.

Wren Suess, an astronomer at the University of California, Santa Cruz, compared Hubble images of galaxies at cosmic noon with Webb images of the same galaxies. At the infrared wavelengths detected by Webb, most of the massive galaxies looked much smaller than they did in Hubble images12. “It potentially changes our whole view of how galaxy sizes evolve over time,” Suess says. Hubble studies suggested that galaxies start out small and grow bigger over time, but the Webb findings hint that Hubble didn’t have the whole picture, and so galaxy evolution might be more complicated than scientists had anticipated.

With Webb just at the beginning of a planned 20-plus years of work, astronomers know they have a lot of changes ahead. “Right now I find myself lying awake at three in the morning,” Kirkpatrick says, “wondering if everything I’ve ever done is wrong.”

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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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‘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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