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China's Chang'e-5 mission offers new insights into evolution of Moon – CCTV

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BEIJING, Oct. 19 (Xinhua) — Chinese researchers have studied the
lunar samples brought back by the Chang’e-5 mission and dated the
youngest rock on the Moon at around 2 billion years in age, extending
the “life” of lunar volcanism 800-900 million years longer than
previously known.

The study, conducted mainly by a research team at the Institute of
Geology and Geophysics (IGG), Chinese Academy of Sciences (CAS), was
presented in three Nature papers and published online Tuesday.

Last year, China’s Chang’e-5 mission retrieved samples from the Moon
weighing about 1,731 grams, which were the first lunar samples in the
world in over 40 years.

“The Chang’e-5 mission was a success and the lunar samples brought
back shed new light on the evolution of the Moon,” said Li Xianhua, an
academician with CAS who led the research team.

DATING MOON ROCKS

“The magma of the Moon has solidified, and the Moon’s geologic
activity has already ceased. When the Moon’s volcanic activity stopped,
it emerged as one of the major issues in its evolutionary history,” said
Li Qiuli, head of the secondary ion mass spectrometry laboratory of
IGG.

The youngest dated rock from the Apollo and Luna missions and lunar
meteorites was around 2.8-2.9 billion years old. However, more samples
are needed and one of the Chang’e-5 tasks is to explore the youngest
magmatic activity of the Moon.

“The dimply surface we see when we look up at the Moon through a
telescope is due to the fact that many asteroids have collided with it
over billions of years. Older rocky regions have experienced more impact
craters over time, and regions with younger rocks have fewer craters,”
said Li Qiuli.

Using the method of chronology known as crater counting, researchers
inferred that the Oceanus Procellarum, the landing site of the Chang’e-5
mission, was most likely to have been witness to one of the Moon’s last
volcanic eruptions. Researchers could then calibrate the results from
crater counting with radioisotopically dated samples.

Radioisotopic dating works on the principle that radioactive elements
have constant decay rates. By measuring the relative abundances of the
parent and daughter isotopes, researchers will know how long the decay
has been taking place.

Using the microscope, researchers manually picked out rock fragments
from their 3-gram lunar samples, which is as difficult as separating
black flour from white flour by hand. Most of these minerals suitable
for dating are only one-twentieth of the diameter of a hair.

Li Qiuli said that the research team had been well-prepared for
studying the lunar samples retrieved by China, and has continuously
developed the ion probe technology in the past decade, reaching an
internationally acclaimed level of expertise.

“Our palms were sweaty as we loaded the sample and turned on the mass
spectrometer. When we saw the age it spat out, we couldn’t believe our
luck. But we wanted to be sure,” said Li Qiuli, adding that they carried
out more than 200 tests.

In total, the team analyzed 47 different rock fragments extracted
from the sample materials and dated the youngest rock on the Moon at
2.03 billion years old. The new age extends the life of lunar volcanism
800-900 million years longer than previously known.

OUT OF EXPECTATION

“The Moon is only around one percent the mass of Earth. At that
strikingly small size, theoretically, at least, it should have
completely solidified at a quick pace. Our team investigated further why
volcanic activity still existed on the Moon so late,” said Li Xianhua.

Lunar scientists focused on KREEP, an acronym built from the letters K
(for potassium), REE (for rare-earth elements) and P (for phosphorus),
which is a distinctive geochemical component of some lunar rocks.

“A widely accepted hypothesis is that radioactive elements (U, Th and
K) supplied the heat necessary for the late volcanic activity. Because
KREEP is rich in radiogenic elements U, Th and K, it is therefore
thought to be responsible for the young volcanic activity,” said Yang
Wei, a researcher with IGG.

“Isotopes are an effective way to identify the KREEP component as
they are like the DNA of a rock and will not change through the magmatic
evolution,” said Yang.

However, the difficulty lies in the small size of the basalt clasts
in the Chang’e-5 lunar samples. It is hard to obtain the isotope ratios
of the Chang’e-5 basalt.

“It’s like DNA testing, which requires a large tube of blood, but we can only use one drop,” said Yang.

Thanks to the institute’s efforts over a decade, a state-of-the-art
method for analyzing samples under high magnification has been
developed, allowing researchers to obtain the strontium and neodymium
isotope ratios of specific minerals.

The results were beyond expectations. The Chang’e-5 basalt, the
youngest basalt dated on the Moon so far, originated from a depleted
mantle source with a KREEP component measuring less than 0.5 percent of
its weight.

In other words, it is unlikely that the KREEP components in the lunar
mantle supplied the heat necessary for the late volcanic activity.

WATER CONTENT

Another possible cause of volcanic activity on the Moon at such a
late age is that the mantle source might have contained water to reduce
its melting point, said scientists.

“The water content of the lunar mantle is a key question for lunar
exploration because it provides critical constraints on the formation of
the Moon. Furthermore, since water can significantly decrease the
melting temperature of rocks, understanding its abundance is important
for understanding the history of lunar volcanism,” said Lin Yangting, a
researcher with IGG.

The large discrepancy in water abundance estimates of the lunar
mantle could be mainly attributed to the Apollo samples and lunar
meteorites being generally quite old.

Most previous lunar samples with measured water content date back to 3
billion years or earlier. Such old rocks could have undergone heavy
modifications over a long time by the impact of asteroids and particles
from the sun.

“The samples retrieved by Chang’e-5 were from a single basaltic lava
flow. With such a simple and clear geological setting, the samples,
therefore, provide a good opportunity to address the question of whether
the mantle reservoir at 2 billion years was wet or dry,” said Lin.

The research team analyzed the water contents and hydrogen isotopes
of pockets of melt preserved in some minerals as well as the mineral
apatite, which can contain water, from Chang’e-5 basalts.

“We used a nano-scale ion probe called the nanoSIMS, a secondary ion
mass spectrometer with an ion beam down to 50 nanometers in diameter.
The relative abundances of the two isotopes of hydrogen (deuterium [D]
and hydrogen [H]) can serve as a ‘fingerprint’ to trace the reservoirs
of water and the magmatic processes involved,” said Lin.

The results indicated that the mantle source of the Chang’e-5 basalts
was drier than the estimated water content based on the Apollo samples
and lunar meteorites, which rules out the possibility that high water
content in the mantle source was the cause of the usually young volcanic
eruption.

The mystery of the late lunar volcanic activity is yet to be solved.

“Our discoveries raise new questions for the future of lunar
exploration and scientists need to further explore the formation
mechanism of the lunar magma,” said Li Xianhua.

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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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