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The Atmosphere of One of The Hottest Exoplanets in The Galaxy Is Full of Metal – ScienceAlert

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Using the light of the star it orbits, astronomers have peered into the atmosphere of an exoplanet 850 light-years away. Not just any exoplanet, but one of the hottest we’ve ever found – and at least seven metals have now been identified floating around its atmosphere as gas.

The exoplanet is WASP-121b, a type of planet we call a hot Jupiter. That’s because it’s a gas giant so close to its star that its temperature rivals that of stars itself; cool stars, to be sure, but stars nevertheless.

WASP-121b is pretty famous, as far as exoplanets go. It was first discovered in 2015, an exoplanet about 1.18 times the mass and 1.81 times the size of Jupiter, on a close orbit of just 1.27 days. Two years later, it became the first exoplanet in whose stratosphere water had been found – although, given the planet’s extreme heat, it’s highly unlikely to be habitable.

Now astronomers have taken a closer look at the exoplanet’s atmosphere, and what they found has surprised them.

At temperatures between 2,500 and 3,000 degrees Celsius (roughly 4,500 and 5,500 degrees Fahrenheit), it isn’t the hottest of these exoplanets that we’ve seen.

But it is so hot that its atmosphere should be a lot simpler than what astronomers have observed in earlier studies – complex molecules should not be able to form in such high temperatures.

These earlier studies suggested that molecules containing the rare metal vanadium and a lack of titanium could explain the spectrum in earlier observations of WASP-121b’s atmosphere.

“Previous studies tried to explain these complex observations with theories that did not seem plausible to me,” said astronomer Jens Hoeijmakers of the Universities of Bern and Geneva in Switzerland.

“But it turned out that they were right. To my surprise, we actually found strong signatures of vanadium in the observations.”

Peering into exoplanet atmospheres is not an easy thing to do. First, you need the exoplanet to pass between us and the star. This is actually a good way to find exoplanets in the first place – you look for really faint, regular dips in starlight to tell you something large is orbiting the star.

To study the atmosphere, you need even fainter signals.

As the exoplanet passes in front of the star, some of the star’s light passes through the atmosphere. Depending on the elements present in the atmosphere, some wavelengths of light will be absorbed and enhanced. If you can take a full spectrum of wavelengths, these will appear as absorption and emission lines.

As you can imagine, the signal isn’t very strong, and there’s a lot of noise. So, for a start, you need good noise reduction tools that aren’t going to destroy the data you need.

The signal can also be magnified and clarified by taking multiple transit spectra and stacking them – so exoplanets with short orbital periods that allow us to take more transit spectra will be easier to analyse. An exoplanet on a 12-year orbit like Jupiter’s would not be an ideal candidate, for example. But WASP-121b’s tight orbit works well.

To obtain a strong spectrum for WASP-121b, Hoeijmakers and his team used three transits previously observed using the HARPS spectrograph instrument on the European Southern Observatory’s La Silla 3.6m telescope, and reprocessed the data.

And they found an interesting metallic cocktail in the exoplanet’s atmosphere. There was the aforementioned vanadium, of course. In addition, the team identified the spectral signatures of iron, chromium, calcium, sodium, magnesium, and nickel. Notably, there’s no titanium – consistent with the earlier findings.

“All metals evaporated as a result of the high temperatures prevailing on WASP-121b, thus ensuring that the air on the exoplanet consists of evaporated metals, among other things,” Hoeijmakers explained.

Hot Jupiters are very mysterious planets, and such analyses of their atmospheres can help us understand them. We don’t know why or how they are so close to their stars, and learning about what’s in their atmospheres can help us figure out if they formed there, or if they migrated inwards from a farther orbit.

But these studies are also helping develop the toolkit for probing planets in search of alien life. What we use to identify iron and sodium today could, with more sensitive equipment, one day help find the molecules produced and used by living organisms, such as oxygen and methane.

“After years of cataloguing what is out there, we are now no longer just taking measurements,” Hoeijmakers said

“We are really beginning to understand what the data from the instruments show us. How planets resemble and differ from each other. In the same way, perhaps, that Charles Darwin began to develop the theory of evolution after characterising countless species of animals, we are beginning to understand more about how these exoplanets were formed and how they work.”

The research has been published in Astronomy & Astrophysics.

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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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