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NASA’s Artemis splashdown will put Orion through a nail-biting test

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The Orion moonship may weigh 25 tons, but in a few days, it will skip like a slight pebble across a pond before plummeting thousands of feet through the air to its target in the Pacific Ocean.

The capsule has begun saying farewell to the moon, with just one more space flyby scheduled for Monday, Dec. 5, before heading home. Already NASA has deployed a crew to San Diego, California, to join the Navy at sea for training exercises to prepare for its unprecedented return.

NASA plans to bring Orion back with a so-called “skip entry” into Earth’s atmosphere. It’ll be the first time the U.S. space agency has ever tried the technique with a passenger spacecraft. The maneuver involves the moonship traveling at an unfathomably high speed and enduring scorching temperatures.

“Orion will come home faster and hotter than any spacecraft has before,” NASA Administrator Bill Nelson told reporters in August. “It’s going to hit the Earth’s atmosphere at 32 times the speed of sound, it’s going to dip into the atmosphere, and bleed off some of that speed, before it starts descending through the atmosphere.”

Orion’s re-entry into Earth’s atmosphere will experience temperatures reaching 5,000 degrees Fahrenheit.
Credit: NASA

Mission leaders say the advantage is breaking up the intense G-force loads — the heavy feeling pushing against a body during extreme acceleration — into two smaller events rather than one severe episode. Though the capsule doesn’t have any people onboard now, NASA believes mastering the skip entry will keep Artemis astronauts who would experience those effects safer in the future. When humans are subjected to forces much greater than normal gravity, their hearts are put under tremendous stress, causing dizziness and sometimes blackouts.

But when the capsule comes back in about a week on Dec. 11, NASA will have to prove Orion can actually survive the ordeal. The re-entry into Earth’s atmosphere will be a nail-biting grand finale to Artemis’ maiden 25-day space voyage, with success hinging on the new Lockheed Martin-built heat shield. The hardware it’s protecting will have to withstand up to 5,000 degrees Fahrenheit, according to NASA.

Imagine an inferno half the temperature of the sun’s surface.

“That heat shield on the back end is going to show us how we’ve taken that material from the Apollo days and brought that into the 21st century,” said Kelly DeFazio, Lockheed’s Orion production director, in August. NASA hopes to put astronauts in Orion as early as 2024 for a ride around the moon. The first landing on the lunar surface would follow on Artemis III, possibly one year later.

The final objective for the Artemis I mission will be a test of the heat shield during re-entry into Earth’s atmosphere.
Credit: NASA

When Orion plunges toward Earth, it will be traveling 24,500 mph. By comparison, the Space Shuttle’s descent reached about 17,500 mph, Nelson said. That initial dip into the upper air will use the atmosphere to slow the capsule down to about 300 mph. Then, it will re-enter for a final descent, slowing down even more with parachutes.

By the time Orion hits water, it should be coasting at 20 mph. NASA will have live coverage of the event beginning at 11 a.m. ET, with the splashdown at about 12:40 p.m., on Dec. 11.


“Orion will come home faster and hotter than any spacecraft has before.”

The idea of a skip entry has existed on paper since NASA’s Apollo days half a century ago but was never attempted. Spaceships then didn’t have the navigational systems and computer power to execute it.

“Apollo was just strictly a direct entry, so that pretty much your landing site was set earlier on, when you departed the moon, with only a minor ability to adjust,” Chris Edelen, deputy manager for Orion integration, told Mashable during a briefing on Wednesday.

NASA astronaut Alan Bean emerges from the Apollo 12 spacecraft after it splashes down in the ocean in August 1969.
Credit: NASA

For Apollo missions, the spacecraft dipped into Earth’s atmosphere and then could travel up to 1,725 miles horizontally before plopping down into the ocean. A swarm of ships and rafts dispersed at sea waited on standby for the recovery operation because of such a vast range of possible places it could fall, according to the U.S. space agency.

But during a skip entry, Orion should be able to fly over 5,500 miles beyond the point it initially pokes into the upper air, giving the capsule more control over where it ultimately splashes down. NASA gets that extra wiggle room by bouncing back out of the atmosphere, where there is little drag on the spacecraft.

“One of the major advances with Artemis is that the spacecraft has the ability…to steer up and out of a denser part of the atmosphere, glide farther downrange or less downrange, so that you can pick the best landing site,” Edelen said.

The U.S. Navy and NASA will work together to recover Artemis I’s Orion spacecraft after it splashes down in the Pacific Ocean on Dec. 11, 2022.
Credit: NASA / Tony Gray
Orion is expected to return to Earth about 50 miles off the coast of San Diego, California.
Credit: NASA / Kim Shiflett

The goal is to drop Orion into the water closer to the U.S. coastline, allowing crews to get to weary returning astronauts quicker and reduce the number of boats, helicopters, and divers needed to get the job done.

Most Apollo moon missions concluded with re-entries into Earth’s atmosphere that put astronauts through the wringer of 6Gs, or six times the normal force of gravity. Apollo 16, the second to last crewed moon mission, had the highest G-level, tipping just over 7Gs.

If all goes according to plan, the three test dummies in Orion — Commander Moonikin Campos, Helga, and Zohar — will instead face two rounds of 4G-level forces. That’s a little more intense than what carnival-goers might experience on a spinning Gravitron, the superfast centrifuge ride that pins people against the wall with about 3.2 times the normal force of gravity.

Perhaps it’s a blessing the two female mannequins aren’t wearing helmets. As limbless torsos, they’d have a hard time hanging onto their hats.

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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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