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SpaceX releases preliminary results from Crew Dragon abort test – Spaceflight Now

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SpaceX’s Crew Dragon capsule is offloaded from the company’s recovery ship, Go Searcher, after returning to Port Canaveral on Jan. 19 following an in-flight launch escape demonstration. Credit: SpaceX

Data from the Jan. 19 in-flight launch escape demonstration of SpaceX’s Crew Dragon spacecraft indicate the performance of the capsule’s SuperDraco abort engines was “flawless” as the thrusters boosted the ship away from the top of a Falcon 9 rocket with a peak acceleration of about 3.3Gs, officials said Thursday.

The Jan. 19 test demonstrated the Crew Dragon’s ability to safely carry astronauts away from a launch emergency, such as a rocket failure, and return the crew to a parachute-assisted splashdown in the Atlantic Ocean.

For its final full-scale test before astronauts ride it into space, the Crew Dragon spacecraft lifted off at 10:30 a.m. EST (1530 GMT) on Jan. 19 from pad 39A at the Kennedy Space Center in Florida. A Falcon 9 rocket carried the capsule aloft — just as it would on a crewed mission — for the first 85 seconds of the mission.

The Crew Dragon began its launch escape maneuver at 10:31:25 a.m. EST (1531:25 GMT) — initiated by a low setting of an on-board acceleration trigger — when the Falcon 9 was traveling at a velocity around 1,200 mph (536 meters per second), according to SpaceX.

Eight SuperDraco thrusters immediately pressurized and ignited as the Falcon 9 rocket’s first stage engines were commanded to shut down as part of the abort sequence.

The escape engines on the Crew Dragon produced nearly 130,000 pounds of thrust at full power. The SuperDracos performed flawlessly, SpaceX said, accelerating the capsule away from the top of the Falcon 9 at a peak acceleration of 3.3Gs.

The SuperDracos accelerated the spacecraft from about 1,200 mph up to more than 1,500 mph (about 675 meters per second) in approximately seven seconds, according to SpaceX.

The Crew Dragon’s SuperDraco thrusters are seen igniting at the time of the launch escape command Jan. 19 to separate from the top of its Falcon 9 rocket. Credit: SpaceX

While the Crew Dragon boosted itself away from the Falcon 9, the rest of the rocket was expected to break apart from aerodynamic forces. It did just that, disintegrating suddenly in a fireball as the crew capsule safely sped away.

Although the Falcon 9 erupted in a fireball seconds after the Crew Dragon escaped the rocket on the Jan. 19 abort test, the crew capsule is designed to get away from a rocket even if it explodes or breaks apart with little warning, according to Elon Musk, SpaceX’s founder and CEO.

“In principle, the system is designed to withstand an adverse booster explosion … that happens even before the escape event,” Musk said at a press conference after Sunday’s abort test. “So it’s it’s intended to be very robust, in principle. And … it’s less of an explosion than it is fire. It’s a fireball, but it’s more for a fireball than it is an over overpressure event like an explosion.

“And since the spacecraft has a very powerful base heat shed and even the leeward side heat shield, it should be really not significantly affected by a fireball,” Musk said. “So it could quite literally — like something out of Star Wars — fly right out of the fireball. Obviously, we want to avoid doing that but. But it is really meant to be something that can fly out of the fireball.”

Unlike other crew capsules, such as Russia’s Soyuz spacecraft and NASA’s Orion deep space exploration vehicle, the Falcon 9 and Crew Dragon do not have a large abort tower mounted to the top of the rocket. The Soyuz and Orion capsules use solid-fueled “tractor” abort systems that pull the spacecraft away from its launch vehicle in the event of a failure.

The Crew Dragon uses SuperDraco engines fed by hydrazine and nitrogen tetroxide propellants to push the capsule away from a failing rocket.

Musk said the Jan. 19 abort test appeared “picture-perfect” at first glance.

SpaceX said the telemetry signal from the Falcon 9 rocket halted around 11 seconds after the escape burn, suggesting a “comfortable” distance of about 4,900 feet (1.5 kilometers) between the Crew Dragon and the Falcon 9 fireball.

The Crew Dragon reached a top speed on the abort test of about Mach 2.3, and a maximum altitude of more than 131,000 feet (40 kilometers).

The capsule jettisoned its unpressurized trunk section, which fell to the Atlantic Ocean, before deploying parachutes to slow itself for splashdown.

The drogue chutes deployed at an altitude of about 19,000 feet (5.8 kilometers), and the Crew Dragon’s four main chutes unfurled around 6,500 feet (2 kilometers) above the ocean.

The capsule splashed down in the Atlantic Ocean around 26 miles (42 kilometers) east of the launch site at 10:38:54 a.m. EST (1538:54 GMT), just under nine minutes after liftoff, according to data released by SpaceX.

Recovery teams picked up the capsule from the sea and hoisted it on the deck of SpaceX’s Crew Dragon retrieval ship — named Go Searcher — for the trip back to Port Canaveral. The spaceship returned to port less than nine hours after launch, demonstrating SpaceX teams can quickly return the capsule to land after a splashdown close to shore.

With the Crew Dragon in-flight escape test complete, engineers will analyze additional data over the coming weeks to verify everything functioned as designed. Assuming no showstoppers, the abort demonstration was the final planned test flight of a full-scale Dragon capsule before NASA clears the commercial crew ferry ship to carry astronauts Doug Hurley and Bob Behnken to the International Space Station.

At least two more drop tests to test the Crew Dragon’s parachutes are planned beginning in mid-February.

The parachutes and launch abort propulsion system have been the primary drivers of Crew Dragon schedule delays over the last year. SpaceX encountered chute failures during the capsule’s development, and an explosion destroyed a Crew Dragon spacecraft during an attempted ground test-firing of its SuperDraco thrusters last year.

While data reviews are underway, NASA is evaluating whether to extend the duration of the Crew Dragon’s first piloted test flight from a week-long mission to the space station to a longer stay that could have Hurley and Behnken live and work aboard the orbiting outpost for months.

Officials said they will factor in the astronauts’ training schedules — which may be lengthened if they’re approved for an extended stay at the space station — and the schedule of other crew rotation missions to the orbiting research lab before setting a target launch date for Hurley and Behnken.

NASA and SpaceX said after the Jan. 19 abort test that the first Crew Dragon launch with astronauts could occur in the second quarter of this year, between the beginning of April and the end of June.

SpaceX’s Crew Dragon spacecraft and Boeing’s Starliner crew capsule are in the final stages of testing before NASA approves the vehicles to carry astronauts. NASA has multibillion-dollar contracts with both companies to develop the human-rated spaceships.

Both capsules are designed to end NASA’s sole reliance on Russian Soyuz spacecraft for crew rotation missions to the space station, an operating scheme NASA has been in since the retirement of the space shuttle in 2011.

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Follow Stephen Clark on Twitter: @StephenClark1.

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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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