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Astronomers Should Shift Focus To Understanding Exoplanets We’ve Already Discovered, Says Researcher – Forbes

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This summer marks nearly three decades since the discovery of 51 Pegasi b, the first known extrasolar planet to circle a sunlike star. Today, there are more than 5000 known planetary systems circling sunlike stars and as many as half of all sunlike stars are now thought to harbor planets.

Exoplanet discoveries in the last decade alone —- in large part due to the work of NASA’s now defunct Kepler Space Telescope —- are enough to boggle the mind. But astronomers are just now beginning to characterize most of these planets in earnest. And arguably that’s where the focus in this burgeoning field of exoplanetary science should now be.

Thus, two years after Covid-19 stymied in-person meetings, one of the world’s major exoplanetary science conferences —- Exoplanets IV (Exo4) —- has just wrapped up in Las Vegas. This past week, I was able to catch up with Exo4’s organizing chair, Jason Steffen, to chew over some of the field’s major issues.

At the top of my list was simply why after decades of looking with both ground- and space-based telescopes, we’ve yet to find a veritable exo-earth.

We know of Earth-sized planets that are near the habitable zone, Steffen, an astrophysicist at the University of Nevada in Las Vegas, told me. But he says that in terms of understanding the properties of their atmospheres; the nature of any liquid water in the atmosphere or on their surfaces, we are still a generation away from telescopes that can give us those types of measurements.

When will we actually start getting spectra from an exo-earth?

2050 is a guess, says Steffen.

What does our study of exoplanets tell us about our own solar system?

“That you can have solar systems that look very different from our own,” said Steffen.

We have a relatively good handle on how our solar system formed and evolved, but exoplanetary science says here’s all the other things that didn’t happen in our solar system that produces different kinds of planets, he says.

As for the synergy between solar system science and exoplanetary science?

Planetary scientists who focus on bodies within our own solar system have an abundance of riches, says Steffen. Mars researchers have had the luxury of taking samples of the surface there and doing in situ analysis which can indicate abundances of dozens of chemical compounds. Solar system scientists also have access to the world’s finest ground-based spectrometers which can identify dozens of chemical species on bodies throughout our solar system —- from Mercury to Pluto.

But at this point, extrasolar planet researchers are lucky if they can detect hydrogen in the atmosphere of an exoplanet, says Steffen. However, he notes that there’s one area where there’s more of a fair competition. That is in extrasolar dynamical measurements of a given planet’s movements. And how the motions of one planet affects the motions and movements of other planets within the same system.

We can understand the orbital properties of exoplanetary systems and compare those with the orbital properties of planets in our solar system, says Steffen.

One of the more interesting presentations at the Exo4 conference involved identifying putative planetary material accreted onto dying stellar remnants known as white dwarfs.

White dwarf stars are superdense and if you dumped something onto a white dwarf it would only stay visible on the surface for a few thousand years before it would all sink into the interior, says Steffen.

So, if you observe something that only has a one-thousand-year lifetime on a star that’s been there for a billion years, that tells you it must have been a recent influx onto the surface of a white dwarf, says Steffen. That must be leftover planetary stuff, he says. This is the only method I know of where you can measure the composition of the planet forming material; that is, the nickel, iron and sodium abundance, says Steffen.

Would this material have originated from planets that were destroyed by the stellar endgame of the system itself?

It’s not clear where that material originates; whether from planets that have been destroyed in the star’s red giant phase, or before the planet was engulfed by the dying red giant, says Steffen.

The other big discussion at Exo4 was evidence for the existence of a third terrestrial mass planet circling our nearest stellar neighbor, Proxima Centauri. Located only 4.2 light years away, Proxima Centauri is a faint red dwarf that is literally the next star over.

The evidence that there’s a third terrestrial planet seems convincing, says Steffen. Whether it’s habitable seems a bit of a stretch but the fact that we observe this around the nearest star to us just indicates how common planet formation actually is, he says.

Is this a numbers game? Should we be out to find the most planets or to study them in detail?

We haven’t done detailed studies of even 10 percent of the planets that have been discovered by Kepler, says Steffen. While there’s value in finding more planets, there’s also value in understanding the planets that we’ve discovered, he says.

Steffen says that the Webb Space Telescope and the next generation of ground-based extremely large telescopes are one way to characterize atmospheres of many of the planets that we’ve found. Observations that span a longer time period also add insights into the systems where those planets reside, he says.

But exoplanetary science still lacks the kind of funding it needs to enable more high risk, high reward initiatives possible, says Steffen.

“Everything is competitive to the point where the overwhelming majority of proposals get rejected,” said Steffen. “The current funding situation [makes] the discipline too risk averse.”

A 30 percent success rate for grant proposals would be much healthier than the less than 10 percent success rate that we see now, he says.

“Science would advance faster if there was enough room for more studies that don’t pan out,” said Steffen.

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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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