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SpaceX’s Crew Dragon slated to bring NASA astronauts home for the first time this weekend – The Verge

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This weekend, two NASA astronauts are slated to return home to Earth inside SpaceX’s new passenger capsule, the Crew Dragon. It’ll be the first time that the Crew Dragon carries passengers back to the planet’s surface, ultimately proving if the vehicle can safely transport people to space and back.

Veteran astronauts Bob Behnken and Doug Hurley will be aboard the spacecraft. The duo made history at the end of May when they launched to the International Space Station inside the Crew Dragon, marking the first time a privately made vehicle carried people to orbit. The launch heralded the return of human spaceflight in the US. The last time people flew to orbit from the United States was in 2011, with the last flight of the Space Shuttle. For nine years, NASA relied on Russian rockets to get astronauts to the ISS — but now the agency can use SpaceX’s vehicles instead.

While the launch received lots of fanfare, getting the astronauts home is an equally critical part of this mission. “From the laws of physics standpoint, we’re only halfway done,” Garrett Reisman, a former NASA astronaut and SpaceX consultant who used to work on the Crew Dragon, tells The Verge. “All that energy you put in [during launch], you have to take every bit of that energy out when you come home.” The Crew Dragon, with Behnken and Hurley inside, will have to undock from the station and plunge itself into Earth’s thick atmosphere. A heat shield should protect the crew from the intense heat created during the descent, which can reach up to 3,500 degrees Fahrenheit. Eventually, the Crew Dragon will deploy a suite of parachutes, slowing the vehicle down so that it can splash down relatively gently in the Atlantic Ocean.

SpaceX has brought multiple spacecraft back from space before, but all of those vehicles were cargo versions of the Crew Dragon, which are different in shape and overall function. The Crew Dragon is more asymmetrical than its predecessor, thanks to the inclusion of an emergency abort system. The company has brought the Crew Dragon back to Earth from space before — but only once, during an uncrewed test flight of the vehicle in March 2019.

“Bringing a spaceship home, that’s a really big deal,” Benji Reed, director of crew mission management at SpaceX, said during a press conference on the landing. “And it’s very important, as part of that sacred honor that we have, for ensuring that we bring Bob and Doug back home to their families, to their kids, and making sure that they’re safe.”

This landing is the last big test for SpaceX as part of NASA’s Commercial Crew Program, an initiative aimed at developing private spacecraft to ferry astronauts to and from low Earth orbit. But before those flights can get started in earnest, SpaceX has to prove to NASA that its Crew Dragon vehicles are safe. The company had to do an uncrewed test flight of the Crew Dragon — sending it to the station and then back home again — as part of a mission called Demo-1. Behnken and Hurley are part of SpaceX’s first crewed test flight, a mission dubbed Demo-2.

The Crew Dragon has remained docked since arriving at the station on May 31st. The astronauts and NASA have done tons of analysis on the Crew Dragon to see how it’s held up in the space environment, and the vehicle seems to be doing just fine. “The systems on Dragon are doing very well,” Steve Stich, the manager of NASA’s Commercial Crew Program, said during the conference. “The spacecraft is very healthy.”

Right now, Behnken and Hurley are scheduled to undock from the space station at around 7:34PM ET on Saturday, August 1st. The capsule will then slowly distance itself from the ISS over the next several hours. Then on Sunday, August 2nd, the Crew Dragon is scheduled to fire up its thrusters at around 1:56PM ET, taking the vehicle out of orbit. The capsule should touch down in the Atlantic Ocean off the coast of Florida about an hour later at around 2:42PM ET. There are seven different landing sites where the Crew Dragon can potentially touch down.

This is all subject to change, as weather is a big limiting factor. The Crew Dragon is the first human-carrying spacecraft, since the Apollo missions, designed to land in water when it comes back to Earth, which means good weather at the landing site is key. NASA doesn’t want the astronauts landing in choppy water after pulling extra G forces on the way down to Earth. If things are too rough, the capsule could tip over, making it difficult for the astronauts to get out.

So for this landing, NASA wants calm waters and winds below 10 miles per hour at the landing site. The mission team doesn’t want rain or lightning in the area either. Originally, things weren’t looking good for a landing this weekend, as Hurricane Isaias was projected to track up the east coast of Florida on Saturday and Sunday. However, SpaceX has the option to land on the western coast of Florida if necessary, and NASA said it is moving forward with the schedule after a recent weather check.

NASA and SpaceX will continue to evaluate if they need to move the undocking. But ultimately, undocking can be called off right at the last minute. “Literally, we have about an hour period where we can undock and if at the last minute we thought that the weather or something wasn’t okay, the SpaceX team could command the vehicle and Bob or Doug could stop and stop the whole undock sequence,” Reed said.

Once the Crew Dragon does undock from the station, that means the spacecraft is most likely going to splash down, according to Reisman. “Once you separate from the space station, you’re committed to coming back,” he says. “Because you are using up consumables on board the vehicle — like propellant, oxygen, and so forth.” SpaceX does have flexibility over when that splashdown occurs. Most of the landing opportunities occur about 15 or 17 hours after undocking, according to Reed. But SpaceX can delay the splashdown until two days later if necessary. The Crew Dragon also has enough resources on board — such as food, oxygen, and more — to last up to three days.

Once in the water, Behnken and Hurley will wait inside the Crew Dragon until SpaceX’s two recovery boats arrive. The first vessel is designed to pull the Crew Dragon out of the water, while a crew of more than 40 people on board will help the astronauts out of the capsule. A second boat will recover the Crew Dragon’s parachutes, which will detach from the capsule after landing. If for some reason the astronauts are experiencing some kind of emergency, there is a helipad on board the main recovery boat, enabling a helicopter to evacuate Behnken and Hurley quickly from the splashdown site. But if that’s not necessary, the boat will take everyone to shore.

A successful landing should help pave the way for SpaceX to start doing routine missions to the ISS. A new Crew Dragon is already slated to fly in late September, carrying a crew of four to the space station for a longer mission. And then in spring of 2021, the Crew Dragon is scheduled for another flight with a crew of four. In fact, that mission next year will use the same Crew Dragon that Behnken and Hurley are coming home in. Just after SpaceX launched this Crew Dragon, NASA approved the company to reuse the capsules on future flights. And SpaceX says it won’t take long to turn them around. “We should be able to have Dragon refurbished and ready to go in just a matter of a couple months — two months,” Reed said.

But before Crew Dragon can be fly again, it has to come home. All eyes are on Behnken and Hurley’s return, and anxiety is high as the two attempt a safe landing. “Until they’re on the boat or even until they’re on shore and I see them get out of the Gulfstream [jet] in Houston, waving to the crowd, I’m still going to be nervous,” Reisman says.

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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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