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Is life a gamble? Scientist models universe to find out – Space.com

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Scientists suspect that the complex life that slithers and crawls through every nook and cranny on Earth emerged from a random shuffling of non-living matter that ultimately spit out the building blocks of life. 

Even so, the details to support the idea are lacking. 

But researchers recently got creative in figuring out the probability of life actually emerging spontaneously from such inorganic matter — a process called abiogenesis.

In the study, Tomonori Totani, a professor of astrophysics at the University of Tokyo, modeled the microscopic world of molecules across the epic scale of the entire universe to see if abiogenesis is a likely candidate for the origin of life. He was essentially looking at whether there were enough stars with habitable planets in the universe at the time to allow complexity to arise. His results, published Feb. 3 in the journal Nature, show the betting odds for life emerging are not good, at least for the observable universe.

Related: 7 wild theories on the origin of life

“I hoped to find at least one realistic path of abiogenesis, to explain abiogenesis by words of science,” Totani told Live Science. “Sometimes people claim that abiogenesis probability is incredibly low and that the origin of life cannot be understood by science. I, as a scientist, dreamed to find a scientific explanation of why we are here.”

Totani’s study looks at a leading hypothesis for abiogenesis, that life as we know it began in what researchers call an RNA world. This hypothesis suggests that before the evolution of proteins and the double-stranded genetic molecule called DNA, or deoxyribonucleic acid — which today provides the instructions for life on Earth — the world was dominated by similar but less efficient molecules called RNA, or ribonucleic acid

In an RNA world, RNA was the first molecule capable of copying and storing information, and of starting and accelerating chemical reactions — two essential characteristics of life on Earth. This world would be a more primitive molecular world to the DNA-protein based chemistry that defines life today.

Although primitive, RNA is made up of many chemicals called monomers that link together to form a polymer. Particularly, RNA is made up of a chain of nitrogen-based molecules called nucleotides. Researchers think that in order for RNA to perform its essential function of copying itself, it needs to be composed of a chain of nucleotides longer than 40 to 60 nucleotides. 

So, how would these RNA molecules made up of at least 40 to 60 nucleotides have popped up on their own? Nucleotides have been shown experimentally to randomly organize into RNA given enough time and under the right conditions. But these experiments show that the abundance of RNA rapidly decreases with the length of their chains and none of the experiments could consistently produce strands longer than 10 monomers.

“It has been experimentally confirmed that RNA polymerization can occur by a basic random process,” Totani said. “Some experiments claimed that more than 50 (monomer long) RNA were produced, but these are not reproducible. One problem is that aggregates are easily mistaken for a long RNA polymer.”

Totani’s model uses the most conservative method of RNA polymerization, where each monomer is attached randomly one-by-one until a chain of monomers is formed. Scientists have suggested that polymers (each made up of multiple monomers) could attach to each other to speed up the process, but Totani said such a process is “highly speculative and hypothetical.”

Life as we know it

Scientists think life emerged on Earth around 500 million years after the planet formed. Given that there are an estimated 10 sextillion (10^22) stars in the observable universe, it may seem that the odds of life popping up in the universe should be good. But researchers have found that the random formation of RNA with a length greater than 40 is incredibly unlikely given the number of stars — with habitable planets — in our cosmic neighborhood. There are too few stars with habitable planets in the observable universe for abiogenesis to occur within the timeframe of life emerging on Earth.

“However, there is more to the universe than the observable,” Totani said in a statement. “In contemporary cosmology, it is agreed the universe underwent a period of rapid inflation, producing a vast region of expansion beyond the horizon of what we can directly observe. Factoring this greater volume [of stars with habitable planets] into models of abiogenesis hugely increases the chances of life occurring.”

After our universe flashed into existence some 13.8 billion years ago during the Big Bang, it underwent a period of rapid expansion that continues today. If we think of the universe as a loaf of bread baking in the oven, our observable universe is like a bubble of air trapped in the dough, where the walls of the bubble are the farthest distance light can travel since the Big Bang. As the loaf rises (inflation), our bubble grows while other pockets of air within the bread get farther away. Our observable bubble of air is all that we can see, even though the rest of the loaf is out there.

Related: From Big Bang to Present: Snapshots of Our Universe Through Time

It is estimated that the whole universe could contain more than 1 googol (10^100) stars. When Totani factored in this new abundance of stars, he found that the emergence of life was no longer improbable, but very likely. 

This may be good news for the RNA world hypothesis, though it could also mean that the search for life in the universe is a hopeless pursuit.

If life first got its start in RNA, “life on Earth was created by a very rare chance of producing a long RNA polymer,” said Totani. “Most likely, Earth is the only planet harboring life in the observable universe. I predict that future observations or explorations of extraterrestrial life will yield no positive results. 

If by chance, life is discovered elsewhere in our cosmic neighborhood, Totani believes it would likely be of the same origin as life on Earth. Life may have hitched a ride from comets and asteroids across interplanetary or interstellar space, seeding the local universe with life from a single origin event.

Totani’s work is far from an answer to one of science’s most existential questions but it may guide further research on the origins of life. Whether we are alone in the universe still remains unanswered, but if Totani’s numbers tell us anything, you shouldn’t bet on it.

Originally published on Live Science.

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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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