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Your Umbrella is Insufficient on a Planet Where it Rains Iron – Universe Today

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Imagine a planet where it rained iron. Sounds impossible. But on one distant exoplanet, which is tidally locked to its star, the nightside has to contend with a ferrous downpour.

The planet is called WASP-76b and it’s about 390 light years away from us in the constellation Pisces. It was discovered in 2013, and it’s the only known planet orbiting the star WASP-76. It’s a huge planet, and the dayside temperature can reach 2,400 Celsius (4350 F) which is hot enough to not only melt iron, but to split molecules into atoms.

“One could say this planet gets rainy in the evening, except that it rains iron.”

Professor David Ehrenreich, Lead Author.

A new study published in Nature outlines the iron-rain nature of the planet. The study is titled “Nightside condensation of iron in an ultrahot giant exoplanet.” Lead author is David Ehrenreich, a professor in the Department of Astronomy in the Faculty of Science at University of Geneva, Switzerland.

The planet was discovered by WASP, the Wide Angle Search for Planets. In a previous study it was identified as an irradiated and bloated Hot Jupiter. Hot Jupiters are a classification of exoplanets that are similar to Jupiter, but orbit very close to their host stars, and have very high surface temperatures.

Artist’s impression of a “hot Jupiter”, a gas giant that orbits it sun at a fraction of the distance between the Earth and Sun. Credit: ESA/ATG medialab

Hot Jupiters are an exotic planet type, compared to the planets in our Solar System. But Wasp-76b is exotic, even for a Hot Jupiter. “One could say this planet gets rainy in the evening, except that it rains iron”, says Ehrenreich, the first author of the study.

This discovery was made with the ESPRESSO instrument on the European Southern Observatory’s (ESO) Very Large Telescope (VLT). ESPRESSO stands for Echelle SPectrograph for Rocky Exoplanets and Stable Spectroscopic Observations. It’s a high-resolution spectrograph that can work with light from a single one of the four 8.2 meter telescopes that make up the VLT. Or it can work with more light, up to all four telescopes at the facility.

The four Unit Telescopes that make up the ESO’s Very Large Telescope, at the Paranal Observatory> Image: By ESO/H.H.Heyer [CC BY 4.0 (http://creativecommons.org/licenses/by/4.0)], via Wikimedia Commons

The unusual planet is tidally-locked to its star. Just like our Moon, it’s day length is the same as its year: It takes as long to orbit its star as it does to complete one rotation. And since it’s so close to its star, this leads to some strange and exotic conditions, which we can hardly call weather.

The star-facing side receives and enormous amount of insolation. But in a Jekyll and Hyde twist, the other side is in darkness. What does that mean?

“In other words, it rains iron on the night side of this extreme exoplanet.”

Christophe Lovis, University of Geneva, Lead Data Analyst at ESPRESSO

It means the Sun-side is baking in heat high enough to melt iron, not into liquid, but into vapour. It also means that vapourized iron is blown from the scorching hot dayside to the much cooler nightside, where it falls as rain. And ESPRESSO detected this vapour where the evening side and the Sun side meet.

“Surprisingly, however, we don’t see iron vapour on the other side of the planet, in the morning,” says Christophe Lovis, a researcher at UNIGE and lead-data analyst of ESPRESSO. “The conclusion is that the iron has condensed during the night. In other words, it rains iron on the night side of this extreme exoplanet.”

The ESPRESSO (Echelle SPectrograph for Rocky Exoplanet and Stable Spectroscopic Observations) instrument collects the light from all four of the 8.2-metre telescopes of the ESO’s Very Large Telescope in Chile. The combined light-collecting area makes it the largest optical telescope in existence. Image: ESO/L. Calcada

The discovery if WASP-76b’s iron rain dates back to 2018, and the first observations made with ESPRESSO. The iron rain, though shocking and unusual from an Earthly perspective, is in-line with predictions.

Planets with extremely high insolation are predicted to be free from clouds, and to be dominated by atomic species. At the much cooler night-side, those species are expected to recombine into molecules. That makes abundant sense.

But it’s never been detected before.

In this case, ESPRESSO detected the neutral iron absorption signal, blue-shifted on the trailing limb. In their paper, the authors make it clear that this “can be explained by a combination of planetary rotation and wind blowing from the hot dayside.” And on the other hand, “… no signal arises from the nightside close to the morning terminator, showing that atomic iron is not absorbing starlight there.”

Tidal locking is not rare. For example, Pluto and its moon Charon are tidally locked to each other, as are the Earth and the Moon. Credit: NASA/JHUAPL/SwRI

This leads to the only real conclusion: “Iron must thus condense during its journey across the nightside.”

WASP-76b and other Hot Jupiters show thermal phase curves that suggest nightside clouds. The authors conclude that “On WASP-76b and similarly hot planets, these clouds could be made out of iron droplets, since liquid iron is the most stable high-temperature iron-bearing condensate. Hence, it could literally rain iron on the nightside of WASP-76b.”

The ESPRESSO instrument was initially devised as a method of discovering new planets, and to characterize known ones. But it’s done so much more.

“We thought very early on that we could use the instrument not only to discover new planets, but also to characterize those that are already known. However, until 2018, we didn’t realise how powerful ESPRESSO really was in this field”, explains Francesco Pepe, professor at the Department of astronomy of the Faculty of Science at UNIGE and principal investigator of the ESPRESSO consortium.

“Thanks to this technology, we now have a completely new way of tracing the climate of the most extreme exoplanets”, concludes David Ehrenreich.

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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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