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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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Chinese national flag debuts on moon: CNSA – Global Times

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Photo:CNSA

The China National Space Administration (CNSA) on Friday showed photos of the first Chinese national flag on the moon. The photo was taken with the flag on board the Chang’e-5 lander vehicle before the ascender blasted off from the moon, marking another proud, inspiring moment in the memories of the Chinese people. 

As soon as the photo was released, it brought cheers from Chinese netizens on twitter-like Sina Weibo. As thousands of netizens left emojis of hearts, clapping hands, and celebrating ribbons on the social platform, some said “if there’s a color for a miracle, it must be the color red on our Chinese national flag.”

The flag, more stylish than before, was made from some special material and weighs only 12 grams. It is the third time that the five-starred red flag on the moon following the mission’s two predecessors, chang’e-3 and -4. Only this time, it comes in the form of actual fabrics other than previous coating on.

The Chinese national flag made its moon debut in December 2013 during the country’s first lunar landing mission of Chang’e-3, and it was recorded in pictures from the spacecraft’s lander and its rover Yutu-1 took for each other.

Chang’e-4 lander and rover Yutu-2 brought China’s national flag to the dark side of the moon, as the Chinese spacecraft made a historic landing in the unvisited region in January 2019.

The flags that Chang’e-3 and -4 carried were in the form of the craft’s coatings, rather than an actual flag. Chinese space technological development has allowed it to take a step forward in the Chang’e-5 mission, the third consecutive safe soft landing on the moon in seven years. 

The Chang’e-5 flag presentation system was developed by China Space Sanjiang Group under the State-owned China Aerospace Science and Industry Corporation, better known as the CASIC.

To ensure a complete and smooth unfolding of the flag, the system adopted a secondary rod-type structure, which is applied in solar panel extending for satellites and other types of spacecraft, CASIC developers told the Global Times on Thursday.

The system weight has been controlled at around one kilogram, and all connecting parts of the system have been given special protection, such as coldness-resistance measures, to help overcome unfavorable lunar surface conditions, including a drastic temperature difference on the moon ranging from 150 C to minus 150 C, Li Yunfeng, the project leader, said in a statement the CASIC company sent to the Global Times.

“An ordinary national flag on Earth would not survive the severe lunar environment,” so the research team also spent more than a year selecting the proper materials to make sure the eventual flag would be strong enough, survive under extreme coldness and heat and capable of showing the fine colors of the national flag and remain so forever, said Cheng Chang, another leading member of the developer team.

The 12-gram national flag represents cutting-edge technology, they said.

How to preserve its original color and shape are the two most crucial questions in designing a national flag that must survive more than 380,000 kilometers away from Earth, under extreme temperatures and radiation during its journey, Wang Ya’nan told the Global Times. 

To get a sense of how difficult the task it is, five of the six flags (except for the one Apollo 11 placed on the moon) brought to the moon in the late 1960s and early 1970s during six US crewed moon landings, have been bleached white due to decades-long solar radiation, although they are reportedly still standing and casting shadows.

Many reports say the Apollo 11 flag was blown over by the exhaust from the ascent engine during lift-off.

The Soviet Union was the first country to imprint its national symbol on the moon, with a football-sized metal ball, carved with its national flag, full of explosives, smashing to the lunar ground in the Luna 2 mission in 1959.

Compared to such a method, China has a more advanced approach, which also greatly increased the complexity of the design, Wang noted.

The Chinese flag that Chang’e-5 displayed officially became the first and only fabric national flag that has ever been placed on the moon in the 21st century, which reminds many of the classic footage of an American national flag planted by Neil Armstrong in the Apollo 11 lunar mission more than five decades ago, observers said.

And they hailed that as the fresh and new icon of human’s lunar exploration, the Chinese national flag would inspire today’s mankind, just as Apollo 11 did, encourage and celebrate generations to make an endeavor to space. 

Displaying a national flag on a celestial body represents the comprehensive strength and technological advancement of the country, Song Zhongping, an aerospace expert and TV commentator, told the Global Times. 

“Yesterday’s memory is still fresh and clear, when the US astronauts stepped outside their cabins and planted the first flag in human history, an American national flag, on the moon in 1969,” Song recalled. “But China is about to showcase our own national flag as well, which I believe is a recognition of the achievements and breakthroughs that we have made, which will be the most valuable thing.”

Some readers have left comments under images and video of the Chang’e-5 landing published on the Global Times twitter account in recent days, saying they would not be convinced and acknowledge China’s achievements until the lander takes an actual photo of the American flag planted by the previous Apollo mission. 

“Is it an original video, or a TikTok post taken in the Gobi desert,” one Twitter user wrote. “Where is the lunar dust while landing,” another asked.

The landing was closely followed by space agencies from all over the world, and the European Space Agency, Russia’s Roscosmos and NASA scientists have extended their congratulations.

Pang Zhihao, a senior space expert based in Beijing, said “the lander vehicle of Chang’e-5 was designed to turn off its engine about two meters above the surface to deliberately avoid blowing dirt.”

And for the sake of innovation, the lander touched down on an unvisited region, which explains why there were no US craft nearby, Pang said.

Global Times

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Footage shows catastrophic collapse of iconic Puerto Rico telescope – cjoy.com

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Dramatic video from Puerto Rico captures the moment when a 816-tonne platform came crashing down on the Arecibo Observatory, shattering one of the world’s largest telescopes and striking a crushing blow to the global scientific community.

The catastrophic collapse happened on Dec. 1, less than two weeks after the U.S. National Science Foundation (NSF) warned that such a disaster was imminent. The NSF had already shuttered operations at the facility after a suspension cable snapped and slashed a hole in the dish last month.

Read more:
Massive Puerto Rico radio telescope collapses after cables snap

The telescope was the largest of its kind when it opened in 1963, and it has contributed to all manner of astronomical discoveries over the years, from asteroids to planets to mysterious radio signals in space. It also won a place in pop culture as the set for such films as Contact and GoldenEye, the first James Bond movie starring Pierce Brosnan.

The observatory’s telescope consisted of a 816-tonne reflector dish platform suspended 137 metres above a massive, bowl-like dish, which measured 305 metres across.

Suspension cables holding up the platform snapped on Dec. 1, dropping the heavy platform on the dish with a tremendous crash.

Video captured by the Arecibo control tower shows one of the three major cables snapping, causing the platform to swing down on the remaining cables before snapping them, too.

The footage shows the reflector dish platform falling apart in mid-air, while dragging down several support towers behind it.

Drone footage captured from one of the support towers shows the moment when the first cable snapped. The cable snapped at the tower, then the whole structure came crashing down, pulling other towers with it and cracking the bowl of the telescope. Large clouds of dust rose from the bowl after the catastrophe.

Read more:
Mysterious radio signal from space traced to ‘zombie’ in our galaxy

Jonathan Friedman, who worked for 26 years at the facility and still lives nearby, described the awful sound of the collapse in an interview with the Associated Press.

“It sounded like a rumble. I knew exactly what it was,” he said. “I was screaming. Personally, I was out of control. … I don’t have words to express it. It’s a very deep, terrible feeling.”

Many scientists, Puerto Rico residents and other public figures mourned the telescope’s loss after it was closed, and again after it collapsed.

Ángel Vázquez, the telescope’s director of operations, said it was no surprise when the telescope fell apart early Tuesday.

“It was a snowball effect,” he said. “There was no way to stop it. … It was too much for the old girl to take.”

© 2020 Global News, a division of Corus Entertainment Inc.

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Footage shows catastrophic collapse of iconic Puerto Rico telescope – Global News

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Dramatic video from Puerto Rico captures the moment when a 816-tonne platform came crashing down on the Arecibo Observatory, shattering one of the world’s largest telescopes and striking a crushing blow to the global scientific community.

The catastrophic collapse happened on Dec. 1, less than two weeks after the U.S. National Science Foundation (NSF) warned that such a disaster was imminent. The NSF had already shuttered operations at the facility after a suspension cable snapped and slashed a hole in the dish last month.

Read more:
Massive Puerto Rico radio telescope collapses after cables snap

The telescope was the largest of its kind when it opened in 1963, and it has contributed to all manner of astronomical discoveries over the years, from asteroids to planets to mysterious radio signals in space. It also won a place in pop culture as the set for such films as Contact and GoldenEye, the first James Bond movie starring Pierce Brosnan.

Story continues below advertisement

The observatory’s telescope consisted of a 816-tonne reflector dish platform suspended 137 metres above a massive, bowl-like dish, which measured 305 metres across.

Suspension cables holding up the platform snapped on Dec. 1, dropping the heavy platform on the dish with a tremendous crash.






0:43
Aerial footage shows damage caused by Arecibo radio telescope collapse


Aerial footage shows damage caused by Arecibo radio telescope collapse

Video captured by the Arecibo control tower shows one of the three major cables snapping, causing the platform to swing down on the remaining cables before snapping them, too.

The footage shows the reflector dish platform falling apart in mid-air, while dragging down several support towers behind it.

Drone footage captured from one of the support towers shows the moment when the first cable snapped. The cable snapped at the tower, then the whole structure came crashing down, pulling other towers with it and cracking the bowl of the telescope. Large clouds of dust rose from the bowl after the catastrophe.

Story continues below advertisement

Read more:
Mysterious radio signal from space traced to ‘zombie’ in our galaxy

Jonathan Friedman, who worked for 26 years at the facility and still lives nearby, described the awful sound of the collapse in an interview with the Associated Press.

“It sounded like a rumble. I knew exactly what it was,” he said. “I was screaming. Personally, I was out of control. … I don’t have words to express it. It’s a very deep, terrible feeling.”

Many scientists, Puerto Rico residents and other public figures mourned the telescope’s loss after it was closed, and again after it collapsed.

Ángel Vázquez, the telescope’s director of operations, said it was no surprise when the telescope fell apart early Tuesday.

“It was a snowball effect,” he said. “There was no way to stop it. … It was too much for the old girl to take.”

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© 2020 Global News, a division of Corus Entertainment Inc.

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