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Scientists thrilled with first look at asteroid sampler in action – Spaceflight Now

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The first images beamed back to Earth by NASA’s OSIRIS-REx spacecraft after it briefly landed an asteroid buoyed expectations Wednesday that the probe collected enough samples to meet the mission’s minimum requirement for return to Earth.

But it will take another week for ground teams to get a reasonably precise estimate of how much material OSIRIS-REx captured during its touch and go landing Tuesday on asteroid Bennu, a loosely-assembled clump of carbon-rich rock and dust spanning a third of a mile (about 500 meters) wide.

The diamond-shaped mini-world was the destination for NASA’s $1 billion Origins, Spectral Interpretation, Resource Identification, Security, Regolith Explorer, which aims to become the first U.S. spacecraft to complete a round-trip journey to an asteroid.

Dante Lauretta, the mission’s chief scientist from the University of Arizona, said Wednesday that the spacecraft’s 11-foot-long (3.4-meter) sampling arm appeared to come down on a “relatively large rock” that measured a little more than 8 inches, or 20 centimeters.

“Literally, we crushed it,” Lauretta said. “When the spacecraft made contact, that rock appears to fragment and shatter, which is great news because that means that ingestible material … is probably being created just by the motion of the spacecraft pushing into the surface.”

The spacecraft’s Touch And Go Sample Acquisition Mechanism, or TAGSAM, on the end of the robot arm is about the size of a dinner plate. About one second after touching the asteroid surface, the sampling system discharged a bottle of high-pressure nitrogen gas to help blow rock fragments and dust into a collection chamber, acting like a reverse vacuum cleaner.

A sped-up video sequence released Wednesday showed the sampling mechanism touching down on the asteroid and generating a cloud of debris.

Ground teams at OSIRIS-REx mission control near Denver received confirmation that the spacecraft contacted the asteroid at 6:08 p.m. EDT (2208 GMT) Wednesday, according to NASA.

In real time, the touch and go landing actually happened more than 18 minutes earlier. It took that long for radio signals from OSIRIS-REx to make the one-way trip at the speed of light from Bennu — located some 207 million miles (333 million kilometers) from Earth — back to mission control.

NASA said Wednesday that a preliminary analysis of data from OSIRIS-REx indicated the spacecraft contacted the asteroid at a relative velocity of just 0.2 mph, or 10 centimeters per second, a fraction of a walking pace. The spacecraft was on the asteroid for around six seconds before the probe fired thrusters to back away from Bennu.

Captured on Oct. 20 during the OSIRIS-REx mission’s Touch-And-Go (TAG) sample collection event, this series of two images shows the SamCam imager’s field of view at the moment before and after the NASA spacecraft touched down on asteroid Bennu’s surface. Credits: NASA/Goddard/University of Arizona

The spacecraft’s autonomous navigation software guided OSIRIS-REx to an on-target touchdown, steering clear of nearby boulders and rugged terrain. The spacecraft found Bennu had a more rocky surface than expected, requiring engineers to introduce more precise navigation algorithms to use natural landmarks on the asteroid to help itself maneuver toward the correct landing site.

The target for Tuesday’s touch and go landing — nicknamed “Nightingale” — was just the size of a tennis court. In the end, OSIRIS-REx contacted the asteroid within a meter, or 3.3 feet, of its target, according to Rich Burns, OSIRIS-REx’s project manager at NASA’s Goddard Space Flight Center.

OSIRIS-REx was relaying low-rate telemetry back to ground controllers as it descended toward Bennu on Tuesday. A few hours later, the spacecraft reestablished a higher-rate data link with Earth and started beaming back images taken during the touch and go, or TAG, maneuver.

Lauretta said much of OSIRIS-REx’s science team was up late Tuesday night to begin analyzing the pictures.

“We were watching the images come down one by one,” Lauretta said.

Finally, well after midnight in Denver, the science team got the picture they were looking for. The craft’s robotic arm appeared to press into the asteroid’s porous surface, and the burst of nitrogen gas launched a cloud of tiny particles off Bennu and into the sampling camera’s field-of-view.

“You can see that particle are flying all over the place,” Lauretta said. “We really did kind of make a mess on the surface of this asteroid, but it’s a good mess. It’s the kind of mess we were hoping for. Lots of material has been mobilized giving us additional confidence that we actually pushed material up into the sampler head.”

Lauretta was in contact with imaging scientists at the University of Arizona in Tucson via a virtual chat app as each new photo arrived on Earth overnight.

“The science team was analyzing them in real-time through the chat feature,” Lauretta said. “As you can imagine, the chat was filled with emojis and wows and all kinds of celebratory remarks.

“The best piece of information we got was that that TAGSAM head looked like it pushed down into the asteroid surface,” he said.

The nitrogen gas bottle was expected to drive rock fragments of up to 2 centimeters — about the size of a U.S. nickel — into OSIRIS-REx’s sample collection chamber. Stainless steel Velcro pads on the outside of the sampling device were also supposed to collect fine-grained dust.

Artist’s illustration of the OSIRIS-REx spacecraft touching down on asteroid Bennu. Credit: NASA/Goddard/CI Lab

Lauretta said the science team was encouraged by the indications that OSIRIS-REx’s sampling mechanism crushed the rocks when it contacted the asteroid. He said the sampling system performed best in pre-launch testing when it pressed into the ground.

“Everything that we can see from these initial images indicate sampling success,” Lauretta said. “We still have some work to do.”

On Thursday, the spacecraft will move its robot arm into position to allow a camera to take closer images of the sample collection mechanism. Officials hope to see asteroid material inside the sampling device, but Lauretta said there’s no guarantee of getting a clear shot of the sample.

OSIRIS-REx will fire its thrusters Friday to halt its flight away from Bennu after the touch and go landing earlier this week, Burns said.

The next activity will be a sample mass measurement Saturday, when OSIRIS-REx will extend its sampling arm and enter a spin to give ground teams an estimate of how much asteroid material it scooped up from Bennu. The spacecraft performed a similar spin maneuver before the touch and go landing.

“That way we can compare the moment of inertia, which will help us determine how much mass is actually in the sampler head,” said Sandra Freund, OSIRIS-REx mission operations manager at Lockheed Martin, which built the spacecraft for NASA.

The minimum amount of asteroid material OSIRIS-REx needs to return to meet mission success criteria is 60 grams, or about 2.1 ounces.

“The best outcome would be that we would collect a massive sample,” said Heather Enos, OSIRIS-REx’s deputy principal investigator at the University of Arizona, before the sample collection attempt. “We say we have a requirement for 60 grams, or 2 ounces, but we have the capability of collecting up to 2 kilograms. I would love for that capsule to be completely full.”

Lauretta said Wednesday that the sample mass measurement has some uncertainty, and a measurement of 80 grams would give managers some confidence that OSIRIS-REx gathered the required amount of material from Bennu.

“If we see SMM (the sample mass measurement) coming in at 80 grams or higher, we have a 90% confidence of having collected 60 grams of regolith,” Lauretta said. “So that’s a key number that I’m looking for.”

NASA has set Oct. 30 for a key decision point on whether to declare success, or plan for another sampling run at a different site on Bennu.

If NASA is satisfied OSIRIS-REx has the required sample mass, ground controllers will send commands for the TAGSAM arm to place the collection canister inside OSIRIS-REx’s landing capsule. Explosive bolts will sever the TAGSAM head from the craft’s robotic arm, and the capsule’s lid will close over the device for the trip home.

If not, the spacecraft could try another touch and go landing as soon as January to snatch up more asteroid material.

The robot explorer is scheduled to depart the vicinity of Bennu in March, when it can set off on an interplanetary trajectory back to Earth. OSIRIS-REx is scheduled to release its return capsule to parachute to a landing in the Utah desert on Sept. 24, 2023.

After OSIRIS-REx’s return carrier lands back on Earth, a recovery team will transport the craft to NASA’s Johnson Space Center in Houston, where scientists will open the canister inside a pristine sample curation laboratory and begin studying its contents.

Researchers at Johnson’s astromaterials lab also analyze rocks returned from the moon by the Apollo astronauts.

Data from NASA’s OSIRIS-REx spacecraft was used to create this shape model of asteroid Bennu at 75-centimeter resolution. Credit: NASA/Goddard/University of Arizona

The team that developed and built the OSIRIS-REx spacecraft took extra measures to ensure the asteroid sample will not be contaminated by organic materials from Earth.

Researchers will use optical and electron microscopes, super-computing labs, and synchrotron accelerators — instruments the size of a large room or a building — in their asteroid sample analysis.

Scientific equipment qualified to fly in space have to operate in extreme temperatures, an airless vacuum, and intense radiation, all while functioning on very little power.

Scientists will attempt to determine the chirality, or handedness, of amino acids and other compounds grabbed from Bennu. Molecules associated with life, such as DNA, have a distinctive orientation. In the case of DNA in organisms on Earth, the double helix always twists in a right-handed direction, and the atoms that make up amino acids in biology are almost always left-handed.

The preference for a left or right orientation among the atoms making up biological molecules makes it easier for chemicals to latch together and build more complex structures.

“Bennu is one of over a million known asteroids in our solar system, and these asteroids are relics of that earliest material that formed the planets in the solar system, and they hold the key information to unlocking how the solar system formed, and how it evolved over time,” said Lori Glaze, director of NASA’s planetary science division.

Named for a bird-like ancient Egyptian deity linked with the sun, creation and rebirth, Bennu follows a path around the sun that intersects Earth’s orbit, and the asteroid makes a relatively close approach to Earth once every six years.

That makes Bennu a potentially hazardous asteroid, and it poses a low threat of eventually hitting Earth. There is a 1-in-2,700 chance of Bennu impacting Earth in the late 2100s.

Bennu was discovered in 1999 by a survey with a ground-based telescope searching for near-Earth asteroids. OSIRIS-REx is the first mission to visit Bennu.

Since arriving at Bennu nearly two years ago, OSIRIS-REx has determined the asteroid is shedding material into space. The mission has also found that Bennu — known as a B-type asteroid — is covered in carbon-rich, water-bearing minerals. The organic material may contain carbon in a form often found in biology or in compounds associated with biology, scientists announced Oct. 8.

Data from OSIRIS-REx’s surveys of Bennu show many of the asteroid’s darkest boulders are weaker and more porous than expected. Scientists say most of the boulders on the asteroid are too weak to survive entry into Earth’s atmosphere, so the specimens targeted by OSIRIS-REx could offer a “missing link” because similar rocks are not well represented in meteorite collections.

“Returned samples from Bennu could help us answer some key astrobiology questions, such as how water and organic materials were delivered to Earth, and the role those key ingredients played in the early initiation of life on Earth,” Glaze said.

Another objective of the OSIRIS-REx mission is to characterize the forces pushing on Bennu and gradually changing its orbit. One of the forces is called the Yarkovsky effect, in which thermal emissions from an asteroid can alter its trajectory through the solar system. Solar radiation pressure is another influence on asteroid orbits.

That data will help scientists better predict when asteroids might threaten Earth.

While it is the first U.S. asteroid sample return probe, OSIRIS-REx is not the only spacecraft currently traveling the solar system on a mission to retrieve materials from an asteroid and bring them back to Earth.

Japan’s Hayabusa 2 spacecraft is on course to bring home samples from asteroid Ryugu on Dec. 6, capping a six-year expedition in space. The mission captured bits of rock from two locations on the half-mile-wide (900-meter) asteroid last year.

Like Bennu, Ryugu is an asteroid rich in carbon and organics.

NASA and the Japan Aerospace Exploration Agency have agreed to share Hayabusa 2 and OSIRIS-REx samples with scientists in each country. JAXA will get about 0.5% of OSIRIS-REx’s samples from Bennu, according to Lauretta.

The Canadian Space Agency will receive 4% of the material from Bennu in exchange for Canada’s contribution of a laser altimeter for OSIRIS-REx, Lauretta said.

Assuming the sample mass measurement Saturday confirms scientists’ suspicions that OSIRIS-REx gathered more than 60 grams of samples from Bennu, the spacecraft’s science mission at Bennu is over, Lauretta said.

“We are then solely focused on the return cruise,” he said. “And quite honestly, the real scientific payoff which this mission is designed to do is that sample return and that sample science, and we’ll be putting our focus and our resources into that.

“We have met, and in most cases, vastly exceeded all the science requirements associated with the remote sensing campaign at Bennu,” Lauretta said Wednesday. “So all we have left to do to deliver on our promise to the agency is get that sample safely back to the Earth, get it into our laboratories, and answer the fundamental questions about the formation of our solar system and why Earth is a habitable world.”

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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.

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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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