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NASA’s DART Kinetic Impactor Spacecraft Launches in World’s First Planetary Defense Test Mission – SciTechDaily

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NASA’s Double Asteroid Redirection Test (DART) spacecraft sets off to collide with an asteroid in the world’s first full-scale planetary defense test mission. Riding atop a SpaceX Falcon 9 rocket, DART took off Wednesday, November 24, from Space Launch Complex 4 East at Vandenberg Space Force Base in California. Credit: NASA/Bill Ingalls

Lighting up the California coastline early in the morning of November 24, a SpaceX Falcon 9 rocket carried <span aria-describedby="tt" class="glossaryLink" data-cmtooltip="

NASA
Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. It’s vision is "To discover and expand knowledge for the benefit of humanity."

“>NASA’s Double Asteroid Redirection Test (DART) spacecraft off the planet to begin its one-way trip to crash into an asteroid.

DART — a mission designed, developed, and managed by the Johns Hopkins Applied Physics Laboratory (APL) in Laurel, Maryland, for NASA’s Planetary Defense Coordination Office — is the world’s first full-scale mission to test technology for defending the planet against potential asteroid or comet hazards. The spacecraft launched Wednesday morning at 1:21 a.m. EST from Space Launch Complex 4 East at Vandenberg Space Force Base in California.

As just one part of NASA’s larger planetary defense strategy, DART will send a spacecraft to impact a known asteroid that is not a threat to Earth, to slightly change its motion in a way that can be accurately measured via ground-based telescopic observations. DART will show that a spacecraft can autonomously navigate to a target asteroid and intentionally collide with it. It’s a method called kinetic impact, and the test will provide important data to help humankind better prepare for an asteroid that might post an impact hazard to Earth, should one ever be discovered.

“The Double Asteroid Redirection Test represents the best of APL’s approach to space science and engineering: identify the challenge, devise an innovative and cost-effective technical solution to address it, and work relentlessly to solve it,” said APL Director Ralph Semmel. “We are honored that NASA has entrusted APL with this critical mission, where the fate of the world really could rest on our success.”

Andy Cheng

Andy Cheng, a Johns Hopkins APL planetary scientist and one of the DART investigation leads, reacts after the successful launch of the DART spacecraft. Cheng was the individual who came up with the idea of DART. He watched the launch from the Mission Operations Center at APL’s Laurel, Maryland, campus. Credit: Johns Hopkins APL/Craig Weiman

At 2:17 a.m. EST, DART separated from the second stage of its launch vehicle. Minutes later, mission operators at APL received the first spacecraft telemetry data and started the process of orienting the spacecraft to a safe position for deploying its solar arrays. Almost two hours later, the spacecraft successfully unfurled its two 28-foot-long roll-out solar arrays. They will power both the spacecraft and NASA’s Evolutionary Xenon Thruster – Commercial (NEXT-C) ion engine, one of several technologies being tested on DART for future application on space missions.

“The DART team overcame the technical, logistical and personal challenges of a global pandemic to deliver this spacecraft to the launch pad, and I’m confident that its next step — actually deflecting an asteroid — will be just as successful,” said Mike Ryschkewitsch, head of APL’s Space Exploration Sector. “It gives me a lot of assurance that if we ever have to embark on an urgent planetary defense mission, we have the people and the playbook to make it happen.”

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DART’s one-way trip is to the Didymos asteroid system, which comprises a pair of asteroids — one small, the other large — that orbit a common center of gravity. DART’s target is the asteroid moonlet Dimorphos, which is approximately 530 feet (160 meters) in diameter and orbits Didymos, which is approximately 2,560 feet (780 meters) in diameter. Since Dimorphos orbits the larger asteroid Didymos at a much slower relative speed than the pair orbits the Sun, the slight orbit change resulting from DART’s kinetic impact within the binary system can be measured much more easily than a change in the orbit of a single asteroid around the Sun.

The spacecraft will intercept the Didymos system in late September of 2022, intentionally slamming into Dimorphos at roughly 4 miles per second (6 kilometers per second) so that the spacecraft alters the asteroid’s path around Didymos. Scientists estimate the kinetic impact will shorten Dimorphos’ orbit by several minutes, and they will precisely measure that change using telescopes on Earth. The results will be used to both validate and improve scientific computer models that are critical to predicting the effectiveness of kinetic impact as a reliable method for asteroid deflection.

Double Asteroid Redirection Test Illustration

Illustration of NASA’s DART spacecraft and the Italian Space Agency’s (ASI) LICIACube prior to impact at the Didymos binary system. Credit: NASA/Johns Hopkins, APL/Steve Gribben

“It is an indescribable feeling to see something you’ve been involved with since the ‘words on paper’ stage become real and launched into space,” said Andy Cheng, one of the DART investigation leads at APL and the individual who came up with the idea of DART. “This is just the end of the first act, and the DART investigation and engineering teams have much work to do over the next year preparing for the main event — DART’s kinetic impact on Dimorphos. But tonight we celebrate!”

DART’s single instrument, the camera DRACO (Didymos Reconnaissance and Asteroid Camera for Optical navigation), will turn on a week from now and provide the first images from the spacecraft. DART will continue to travel just outside of Earth’s orbit around the Sun for the next 10 months until Didymos and Dimorphos will be a relatively close 6.8 million miles (11 million kilometers) from Earth.

A sophisticated guidance, navigation, and control (GNC) system, working with algorithms developed at APL called SMART Nav (Small-body Maneuvering Autonomous Real Time Navigation) will enable the DART spacecraft to identify and distinguish between the two asteroids and then, working in concert with the other GNC elements, direct the spacecraft toward Dimorphos, all within roughly an hour of impact.

Provided by the Italian Space Agency, the Light Italian CubeSat for Imaging of Asteroids (LICIACube) will ride along with DART and be released prior to impact. LICIACube will then capture images of the DART impact, the resulting ejecta cloud and possibly a glimpse of the impact crater on the surface of Dimorphos. It will also look at the back side of Dimorphos, which DRACO will never have a chance to see, gathering further data to enhance the kinetic models.

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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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