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NASA to roll back its mega rocket after failing to complete countdown test – Ars Technica

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Enlarge / The Space Launch System rocket rolls out of the Vehicle Assembly Building in mid-March, 2022.
Trevor Mahlmann

After three attempts to complete a critical fueling test of the Space Launch System rocket, NASA has decided to take a break.

On Saturday night the space agency announced plans to roll the large SLS rocket from the launch pad at Kennedy Space Center to the Vehicle Assembly Building in the coming days. This marks a notable step back for the program, which has tried since April 1 to complete a “wet dress rehearsal” test, during which the rocket is fueled and brought to within 10 seconds of launch.

The decision comes after three tries during the last two weeks. Each fueling attempt was scuttled by one or more technical issues with the rocket, its mobile launch tower, or ground systems that supply propellants and gases. During the most recent attempt, on Thursday April 14, NASA succeeded in loading 49 percent of the core-stage liquid oxygen fuel tank and 5 percent of the liquid hydrogen tank.

While this represents progress, it did not include the most dynamic portion of the test, during which the rocket is fully fueled and pressurized; and it, the ground systems, and computer systems are put into a terminal countdown when every variable is closely monitored. NASA had hoped to complete this wet dress rehearsal test to work out the kinks in the complicated launch system so that, when the rocket is rolled out later this year for its actual launch, the countdown will proceed fairly smoothly.

NASA said that its contractors, as well as its agency’s, will use the next several weeks to address problems that cropped up during the fueling tests when the SLS rocket returns to the large Vehicle Assembly Building. For example, gaseous nitrogen system supplier Air Liquide will upgrade its capabilities. NASA will also replace a faulty check valve on the upper stage of the rocket, as well as fix a leak on the mobile launch tower’s “tail service mast umbilical,” a 10-meter-tall structure that provides propellant and electricity lines to the rocket on the pad.

The space agency announcement did not provide any information about schedule impacts. It seems probable that it will take a week or so to prepare and roll the SLS rocket back to the Vehicle Assembly Building. Work on the rocket at that location will probably take up most of the month of May, at least.

NASA will then have to make some difficult decisions. It could opt to roll the rocket and its mobile launch tower to the pad a second time and try again to complete the wet dress rehearsal test. Then, following its normal procedure, NASA would roll the rocket back to its assembly building to arm the “flight safety system,” before rolling for a third time to the launch pad for liftoff. It seems the absolute earliest the SLS rocket could launch in such a scenario would be August, but a fall liftoff may be more likely.

Another option NASA could pursue is to roll-out, complete a wet-dress test on the pad, and then if that is successful, to go ahead and launch within a few days. Under such a scenario NASA might be able to launch the SLS rocket in June or July. However, this would be risky due to the flight safety system.

During a teleconference on Friday, Artemis Launch Director Charlie Blackwell-Thompson confirmed that there is a 20-day timeline once the flight safety system is armed. (This is a range safety mechanism used by all orbital rockets that destroys the booster in case it veers off course.) After the system is activated, it will take about a week to make final preparations in the Vehicle Assembly Building and a week to roll to the launch pad and make preparations there. That would leave just a single week for a fueling test, recycling of commodities, and perhaps one or two launch attempts before the 20-day window closes.

In other words, this means the wet dress test would have to be nearly flawless, and then the launch attempt would need to be flawless as well. It would also mean that summertime weather in Florida—when there are numerous thunderstorms and other inclement conditions—would have to cooperate.

Finally, NASA engineers must weigh a host of other factors, such as wear and tear on the rocket, its side-mounted boosters being exposed outside, as well as seemingly innumerable lifetime considerations with the hardware. For example, agency officials are closely tracking the health of the fuel in the solid-rocket boosters, which were stacked about 16 months ago, among other issues.

Still, NASA seems confident that it will get through this painful teething process for the SLS rocket: a program that is now 11 years old and in which NASA has invested more than $30 billion in the rocket and ground systems now being tested.

“There’s no doubt in my mind that we will finish this test campaign, and we will listen to the hardware, and the data will lead us to the next step,” Blackwell-Thompson said Friday. “And we will take the appropriate steps, and we will launch this vehicle. I don’t know exactly what that date is, but there’s no doubt in my mind that we’ll finish the test campaign, and we will be ready to go fly.”

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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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