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They found two new craters on the moon and discovered a new mystery – Kathimerini English Edition

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After months of scrutinizing photographs of the lunar surface, scientists have finally found the crash site of a forgotten rocket stage that struck the far side of the moon in March.

They still do not know for sure which rocket the wayward debris originated from. And they are perplexed about why the impact excavated two craters and not just one.

“It’s cool, because it’s an unexpected outcome,” said Mark Robinson, a professor of geological sciences at Arizona State University who serves as the principal investigator for the camera aboard NASA’s Lunar Reconnaissance Orbiter, which has been photographing the moon since 2009. “That’s always way more fun than if the prediction of the crater, its depth and diameter, had been exactly right.”

Robinson reported the discovery Friday on the website that stores images taken by the lunar orbiter.

The rocket crash intrigue started in January when Bill Gray, developer of Project Pluto, a suite of astronomical software used in calculating the orbits of asteroids and comets, tracked what looked like the discarded upper stage of a rocket. He realized it was on a collision course with the far side of the moon.

The crash was certain, at about 7:25 a.m. Eastern time on March 4. But the exact orbit of the object was not known, so there was some uncertainty about the time and place of the impact.

Gray said the rocket part was the second stage of a SpaceX Falcon 9 that launched the Deep Space Climate Observatory, or DSCOVR, for the National Oceanic and Atmospheric Administration in February 2015.

He was wrong.

A NASA engineer pointed out that the launch trajectory of DSCOVR was incompatible with the orbit of the object Gray was tracking. After some more digging, Gray concluded that the most likely candidate was a Long March 3C rocket that was launched from China a few months earlier, on Oct. 23, 2014.

Students at the University of Arizona reported that an analysis of the light reflected from the object found that the mix of wavelengths matched similar Chinese rockets rather than a Falcon 9.

But a Chinese official denied it was part of a Chinese rocket, saying that the rocket stage from that mission, which launched the Chang’e-5 T1 spacecraft, had reentered Earth’s atmosphere and burned up.

Regardless of what rocket it was part of, the object continued to follow the spiraling path dictated by gravity. At the predicted time, it slammed into the far side of the moon within the 350-mile-wide Hertzsprung Crater, out of sight of anyone on Earth.

The Lunar Reconnaissance Orbiter was not in a position to watch the impact, but the hope was that a freshly carved crater would show up in a photograph that the spacecraft took later.

Gray’s software made one prediction of the impact site. Experts at NASA’s Jet Propulsion Laboratory calculated a location a few miles to the east, while members of the Massachusetts Institute of Technology’s Lincoln Laboratory expected that the crash would occur tens of miles to the west.

That meant the researchers had to search a swath about 50 miles long for a crater a few tens of feet wide, comparing the lunar landscape before and after the crash to identify recent disturbances.

Robinson said he worried that “it was going to take us a year of imaging to fill in the box.”

While the Lunar Reconnaissance Orbiter has photographed the vast majority of the moon several times over the past 13 years, there are spots it has missed. It turned out that some of the gaps were near the expected crash site.

Robinson remembered thinking of Murphy’s Law and joking, “I know exactly where it’s going to hit.”

Because the crash was predicted a month ahead of time, the mission team was able to fill in most of the gaps.

Then the search started.

Usually, a computer program does the comparison, but that works best if the before-and-after pictures are taken at the same time of day. For this search, many of the images were taken at different times, and the difference in shadows confused the algorithm.

With all the false positives, “we just sat down and had several people manually going through the millions of pixels,” Robinson said.

Alexander Sonke, a senior in Arizona State’s geological sciences department, contributed to the effort. He estimated that he had spent about 50 hours over several weeks performing the tedious task.

Sonke graduated in May. He got married. He went on his honeymoon. A week and a half ago was his first day back at work — he is about to embark on his graduate school studies with Robinson as his adviser — and he resumed the search for the impact site.

He found it.

Sonke said he had seen “a group of pixels that looked significantly different in brightness” as the before-and-after images blinked back and forth.

“I was pretty confident when I saw it that this was a new geologic feature,” Sonke said. “I certainly jumped out of my seat a little, had a feeling that this was definitely it, and then tried to kind of restrain my excitement.”

The eastern crater, about 20 yards in diameter, is superimposed on the slightly smaller western one, which most likely formed a few thousandths of a second before the eastern one, Robinson said.

This is not the first time a spacecraft part has hit the moon. For example, pieces of the Saturn 5 rockets that took astronauts to the moon in the 1970s also carved craters. But none of those impacts created a double crater.

The reason this one did might point to its mystery identity. The October 2014 Chinese mission carried the Chang’e-5 T1 spacecraft, a precursor for another mission, Chang’e-5, which landed on the moon and brought rock samples back to Earth.

The precursor T1 spacecraft did not include a lander, but Robinson surmises that it had a heavy mass at the top of the stage to simulate the presence of one. If so, then rocket engines at the bottom and the lander simulator at the top could have created the two craters.

“That’s sheer speculation on my part,” Robinson said.

The other parts of the rocket stage would have been thin, light aluminum, not likely to make much of a dent on the lunar surface.

The actual impact site lay between the sites predicted by Gray and the NASA Jet Propulsion Laboratory, close to the NASA one. “It was within the margins of error that we had computed,” Gray said.

It was also fortunate that the Lunar Reconnaissance Orbiter team had filled in the gaps — called gores, in the language of mapmakers — in the images. “As Murphy would have it, that thing impacted in what was one of the gores,” Robinson said. “If I hadn’t been alerted, we wouldn’t have had a before image.”

The scientists might eventually have found the crash site. Dirt tossed out from a gouged crater is usually brighter, growing darker over time. That is how scientists identified the craters caused by Saturn 5 stages.

But they would still be looking for one small bright spot in the haystack of the moon.


This article originally appeared in The New York Times.

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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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