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Dealing with dust: A back-to-the-moon dilemma – SpaceNews

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If the political, technical and budgetary stars align for NASA and its partners in coming years, the moon could be the go-to place as the century unfolds. Astronauts would again explore Earth’s celestial next-door neighbor, perhaps setting in motion future mining endeavors to extract ices likely lurking in sunlight-shy craters for processing into water, oxygen, and rocket propellant. Humans that “settle in” on the moon could well be a future prospect.

Earth’s moon is a dusty denizen of deep space. View from the International Space Station. Credit: NASA/Jeff Williams

The next chapter in the U.S. human exploration of the moon, the Artemis Project, will dispatch crews there for extended periods of time, building upon Apollo’s heritage. Between 1969 and the end of 1972, a dozen astronauts kicked up the powdery regolith, the topside dirt of the moon. But there’s one flash back message from the Apollo moonwalkers worth heeding: the place is a Disneyland of dust.

During their landings, dust blown up into the thin lunar atmosphere impacted astronaut visibility. Once crews were out and about on the moon, the dust had deleterious effects on their spacesuits, helmets, equipment and instrumentation. Apollo expedition members could not escape tracking lunar material inside their lunar landers. After doffing their helmets and gloves, moonwalkers could feel the abrasive nature of the dust, even experiencing an “Apollo aroma” — a distinctive, odoriferous smell.

As explained by Apollo 17’s moon landing crew:

“I think dust is probably one of our greatest inhibitors to a nominal operation on the moon. I think that we can overcome other physiological or physical or mechanical problems except dust,” said mission commander Eugene Cernan. “One of the most aggravating, restricting facets of lunar surface exploration is the dust and its adherence to everything no matter what kind of material, whether it be skin, suit material, metal, no matter what it be and its restrictive friction-like action to everything it gets on,” said lunar module pilot and geologist, Harrison Schmitt.

AGENCY, INDUSTRY CONCERN

Study groups and technologists are assessing ways to lessen the negative impact of lunar dust on the astronauts, their equipment, and surface operations.

Apollo 17 commander Eugene Cernan prepares to doff dust-covered moonwalking spacesuit. Credit: NASA

Joel Levine, a research professor in applied science at The College of William and Mary in Williamsburg, Virginia, was convener and chair of a NASA workshop on lunar dust and its impact on human exploration. The message from that workshop held in February was clear. “Prior to the first Artemis human landing on the moon, we must better understand the particle size distribution, structure, chemical composition, potential toxicity, magnetic and electrical properties and the dynamics and distribution of lunar dust,” he said.

The workshop findings were published Sept. 24 as a NASA Engineering and Safety Center Technical Assessment Report, stating that the dust problem “is an agency and industry concern affecting most mission subsystems and it must be addressed.” The report also said that it is crucial that measurements and experiments be taken and carried out on the lunar surface by precursor landers to find out dust characteristics “that will influence hardware design, and provide toxicology data to safeguard crew health.”

PROTECTING LUNAR GEAR

Future machinery on the moon will be presented challenges, said Gerald Sanders, an expert on in-situ resource utilization (ISRU) for NASA’s Space Technology Mission Directorate at Johnson Space Center in Houston. Unlike other equipment and instruments that operate on the moon, ISRU systems and hardware need to operate continuously and in direct contact with lunar regolith and dust for very long periods of time. It is vital, he said, to develop techniques and technologies to resist abrasion, to safeguard optical coatings, as well as protect rotating mechanisms. In the end, easily replaceable components in lunar-situated gear will be critical.

Apollo 17 helmets and dusty spacesuits stuffed inside a lunar lander following the last human treks on the moon in December 1972. Credit: NASA

“While the Apollo missions and samples returned to Earth have provided a wealth of information, it will not be until the VIPER rover enters a permanently shadowed region that we will get a true sense of what the regolith is like to design future ice mining equipment,” Sanders said. NASA’s Volatiles Investigating Polar Exploration Rover, or VIPER, is a mobile robot that will go to the moon’s south pole, perhaps as early as December 2022 under NASA’s Commercial Lunar Payload Services program.

Philip Metzger, a planetary physicist with the Planetary Science faculty at the University of Central Florida, has focused his research on dust transport and its effects due to landing spacecraft on the moon.

“Lunar lander engine exhaust blows dust, soil, gravel, and rocks at high velocity and will damage surrounding hardware such as lunar outposts, mining operations, or historic sites unless the ejecta are properly mitigated,” said Metzger.

Decades of research have developed a consistent picture of the physics of rocket exhaust blowing lunar soil, “but significant gaps exist,” Metzger added. “No currently available modeling method can fully predict the effects. However, the basics are understood well enough to begin designing countermeasures.”

Metzger is principal investigator for the Ejecta Sheet Tracking, Opacity, and Regolith Maturity (STORM) instrument, set to fly on a Masten Space Systems Xodiac vertical takeoff and vertical landing system. The upcoming flight in Mojave, California, will gauge the density and sizes of particles that churn up during terrestrial simulations of lunar landings.

INTEGRATED DUST MITIGATION STRATEGY

NASA wants to place the first woman and next man at the lunar south pole in 2024. That location is advocated as a future base camp given possible access to ice and other mineral resources. However, still unknown are the true physical properties of the lunar dust and regolith in the polar regions.

Dust being displaced by engine exhaust from the Apollo 15 mission’s lunar lander, Falcon. Credit: NASA

Jorge Núñez of the Planetary Exploration Group at Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Maryland, said a host of questions need to be tackled. “We can approximate and extrapolate based on the data we already have, but we will not really know until we land in those regions,” he said.

“As we learned from the Apollo missions, lunar dust can cause a wide range of issues, including being a hazard to astronaut health, sticking to all kinds of surfaces like spacesuits, visors and windows, solar panels, and radiators,” Núñez said. Lunar dust also degrades seals, fabrics, and mechanisms. Dealing with dust is going to require an “integrated dust mitigation strategy,” he added, such as using slow, methodical movements and allow adequate time for dust cleaning protocols, as well as keeping spacesuits outside of the pressurized habitat or lunar rover, to utilizing an electrodynamic dust shield to repel dust off materials.

Núñez said that NASA’s Lunar Surface Innovation Initiative is accelerating the development of many of these dust mitigation technologies that are important for enabling human missions on the surface of the moon.

MOON SIMULANTS

The reactive nature of lunar dust to humans is another area flagged by APL’s Karl Hibbitts, lead facilitator for the ISRU focus group of the Lunar Surface Innovation Consortium. The lunar dust has been known to be troublesome in this area since the Apollo era. The particles are chemically very reactive, he said, thus the potential health concern (although various passivation techniques to make them less reactive are being explored).

Apollo 11 Lunar Module Pilot Buzz Aldrin’s bootprint. Aldrin photographed this bootprint about an hour into their lunar extra-vehicular activity on July 20, 1969, as part of investigations into the soil mechanics of the lunar surface. This photo would later become synonymous with humankind’s venture into space. Credit; NASA

“We have attempted to study the reactivity of lunar soils in the lab,” Hibbitts said, “but the studies I know of have all been on samples already altered by the Earth’s atmosphere. The new studies on carefully curated lunar soils will hopefully shed some new insights.” Furthermore, as far as “simulants” go — concoctions of made-on-Earth material to imitate the properties of the lunar regolith — one has to choose which properties one needs the simulants to mimic. “It’s not possible to create literally tons of lunar soil, or possibly even a small amount. Facilities are just now learning how to make realistic agglutinates,” he added, and yet to be reproduced is the nanophase metallic iron that’s resident in the moon’s regolith.

“We’re getting better at approximating the shape and size distribution function, but the reactivity could only be mimicked by production in a vacuum chamber and will always be limited to tiny quantities,” Hibbitts told SpaceNews.

So far, human contact with tiny, very sharp, glassy lunar dust particles only occurred briefly during the Apollo missions, said Peter Sim, an emergency medicine specialist in Newport News, Virginia. But in returning to the moon and establishing a long-term presence, lunar dust, in sufficient doses, represents a “toxic threat” to human health, he said.

The respiratory system is particularly susceptible, Sim said, but the eyes, skin, and possibly the gastrointestinal tract and other organs may also be affected. Primary prevention of human exposure to lunar dust “should be our number one goal,” he advised.

He added that NASA’s new Exploration Extravehicular Mobility Unit (xEMU) spacesuit will help keep the dust at bay. It has a group of dust-tolerant features, to prevent inhalation, or contamination of the suit’s life support system. Still, keeping habitats dust-free by minimizing incursions, and using effective atmospheric filtration systems, will be a major challenge. “Monitoring of the dust that is present inside lunar habitats will be crucial, since the hab is the place where astronauts are most likely to be exposed. Because of this, the quantity, size, and potential toxicity of the ‘hab dust’ is of paramount importance,” he said.


SpaceNews contributor Leonard David is the author of “Moon Rush: The New Space Race” published by National Geographic in May 2019.

This article originally appeared in the Dec. 14, 2020 issue of SpaceNews magazine.

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New species of crested dinosaur identified in Mexico

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A team of palaeontologists in Mexico have identified a new species of dinosaur after finding its 72 million-year-old fossilized remains almost a decade ago, Mexico’s National Institute of Anthropology and History (INAH) said on Thursday.

The new species, named Tlatolophus galorum, was identified as a crested dinosaur after 80% of its skull was recovered, allowing experts to compare it to other dinosaurs of that type, INAH said.

The investigation, which also included specialists from the National Autonomous University of Mexico, began in 2013 with the discovery of an articulated tail in the north-central Mexican state of Coahuila, where other discoveries have been made.

“Once we recovered the tail, we continued digging below where it was located. The surprise was that we began to find bones such as the femur, the scapula and other elements,” said Alejandro Ramírez, a scientist involved in the discovery.

Later, the scientists were able to collect, clean and analyze other bone fragments from the front part of the dinosaur’s body.

The palaeontologists had in their possession the crest of the dinosaur, which was 1.32 meters long, as well as other parts of the skull: lower and upper jaws, palate and even a part known as the neurocranium, where the brain was housed, INAH said.

The Mexican anthropology body also explained the meaning of the name – Tlatolophus galorum – for the new species of dinosaur.

Tlatolophus is a mixture of two words, putting together a term from the indigenous Mexican language of Nahuatl that means “word” with the Greek term meaning “crest”. Galorum refers to the people linked to the research, INAH said.

 

(Reporting by Abraham Gonzalez; Writing by Drazen Jorgic; Editing by Ana Nicolaci da Costa)

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Alberta family searches for answers in teen's sudden death after COVID exposure, negative tests – CBC.ca

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A southern Alberta mother and father are grappling with the sudden, unexplained death of their 17-year-old daughter, and with few answers, they’re left wondering if she could be the province’s youngest victim of COVID-19.

Sarah Strate — a healthy, active Grade 12 student at Magrath High School who loved singing, dancing and being outdoors — died on Monday, less than a week after being notified she’d been exposed to COVID-19.

While two tests came back negative, her parents say other signs point to the coronavirus, and they’re waiting for more answers. 

“It was so fast. It’s all still such a shock,” said Sarah’s mother, Kristine Strate. “She never even coughed. She had a sore throat and her ears were sore for a while, and [she had] swollen neck glands.”

Kristine said Sarah developed mild symptoms shortly after her older sister — who later tested positive for COVID-19 —  visited from Lethbridge, one of Alberta’s current hot spots for the virus.

The family went into isolation at their home in Magrath on Tuesday, April 20. They were swabbed the next day and the results were negative.

‘Everything went south, super-fast’

By Friday night, Sarah had developed fever and chills. On Saturday, she started vomiting and Kristine, a public health nurse, tried to keep her hydrated.

“She woke up feeling a bit more off on Monday morning,” Kristine said. “And everything went south, super-fast.”

Sarah had grown very weak and her parents decided to call 911 when she appeared to become delirious.

“She had her blanket on and I was talking to her and, in an instant, she was unresponsive,” said Kristine, who immediately started performing CPR on her daughter.

When paramedics arrived 20 minutes later, they were able to restore a heartbeat and rushed Sarah to hospital in Lethbridge, where she died.

“I thought there was hope once we got her heart rate back. I really did,” recalled Sarah’s father, Ron.

“He was praying for a miracle, and sometimes miracles don’t come,” said Kristine.

Strate’s parents say her health deteriorated quickly after being exposed to COVID-19. She died at Chinook Regional Hospital in Lethbridge on Monday. (Ron Strate)

Searching for answers

At the hospital, the family was told Sarah’s lungs were severely infected and that she may have ended up with blood clots in both her heart and lungs, a condition that can be a complication of COVID-19.

But a second test at the hospital came back negative for COVID-19.

“There really is no other answer,” Ron said. “When a healthy 17-year-old girl, who was sitting up in her bed and was able to talk, and within 10 minutes is unconscious on our floor — there was no reason [for it].”

The province currently has no record of any Albertans under the age of 20 who have died of COVID-19.

According to the Strate family, the medical examiner is running additional blood and tissue tests, in an effort to uncover the cause of Sarah’s death.

‘Unusual but not impossible’

University of Alberta infectious disease specialist Dr. Lynora Saxinger, who was not involved in Sarah’s treatment, says it is conceivable that further testing could uncover evidence of a COVID-19 infection, despite two negative test results.

However, she hasn’t seen a similar case in Alberta.

“It would be unusual but not impossible because no test is perfect. We have had cases where an initial test is negative and then if you keep on thinking it’s COVID and you re-test, you then can find COVID,” she said.

According to Saxinger, the rate of false negatives is believed to be very low. But it can happen if there are problems with the testing or specimen collection.

She says people are more likely to test positive after symptoms develop. 

“The best sensitivity of the test is around day four or five of having symptoms,” she said. “So you can miss things if you test very, very early. And with new development of symptoms, it’s always a good time to re-test because then the likelihood of getting a positive test is a little higher. But again, no test is perfect.” 

Sarah deteriorated so quickly — dying five days after she first developed symptoms — she didn’t live long enough to make it to her follow-up COVID-19 test. Instead, it was done at the hospital.

‘An amazing kid’

The Strate family now faces an agonizing wait for answers — one that will likely take months — about what caused Sarah’s death.

But Ron, who teaches at the school where Sarah attended Grade 12, wants his daughter to be remembered for the life she lived, not her death.

Strate, pictured here at three years old, had plans to become a massage therapist. She attended Grade 12 at Magrath High School and was an active, healthy teenager who was involved in sports, music and the school’s suicide prevention group. (Ron Strate)

Sarah was one of five children. Ron says she was strong, active and vibrant and had plans to become a massage therapist after graduating from high school.

She played several sports and loved to sing and dance as part of a show choir. She was a leader in the school’s suicide prevention group and would stand up for other students who were facing bullying.

“She’s one of the leaders in our Hope Squad … which goes out and helps kids to not be scared,” he father said.

“She’s an amazing kid.”

Sarah would often spend hours helping struggling classmates, and her parents hope her kindness is not forgotten.

“She’d done so many good things. Honestly, I’ve got so many messages from parents saying, ‘You have no idea how much your daughter helped our kid,'” said Ron.

“This 17-year-old girl probably lived more of a life in 17 years than most adults will live in their whole lives. She was so special. I love her so much.”

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China launches key module of space station planned for 2022

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BEIJING (Reuters) -China launched an unmanned module on Thursday containing what will become living quarters for three crew on a permanent space station that it plans to complete by the end of 2022, state media reported.

The module, named “Tianhe”, or “Harmony of the Heavens”, was launched on the Long March 5B, China’s largest carrier rocket, at 11:23 a.m. (0323 GMT) from the Wenchang Space Launch Centre on the southern island of Hainan.

Tianhe is one of three main components of what would be China’s first self-developed space station, rivalling the only other station in service – the International Space Station (ISS).

The ISS is backed by the United States, Russia, Europe, Japan and Canada. China was barred from participating by the United States.

“(Tianhe) is an important pilot project in the building of a powerful nation in both technology and in space,” state media quoted President Xi Jinping as saying in a congratulatory speech.

Tianhe forms the main living quarters for three crew members in the Chinese space station, which will have a life span of at least 10 years.

The Tianhe launch was the first of 11 missions needed to complete the space station, which will orbit Earth at an altitude of 340 to 450 km (211-280 miles).

In the later missions, China will launch the two other core modules, four manned spacecraft and four cargo spacecraft.

Work on the space station programme began a decade ago with the launch of a space lab Tiangong-1 in 2011, and later, Tiangong-2 in 2016.

Both helped China test the programme’s space rendezvous and docking capabilities.

China aims to become a major space power by 2030. It has ramped up its space programme with visits to the moon, the launch of an uncrewed probe to Mars and the construction of its own space station.

In contrast, the fate of the ageing ISS – in orbit for more than two decades – remains uncertain.

The project is set to expire in 2024, barring funding from its partners. Russia said this month that it would quit the project from 2025.

Russia is deepening ties with China in space as tensions with Washington rise.

Moscow has slammed the U.S.-led Artemis moon exploration programme and instead chosen to join Beijing in setting up a lunar research outpost in the coming years.

(Reporting by Ryan Woo and Liangping Gao; Editing by Christian Schmollinger, Simon Cameron-Moore and Lincoln Feast.)

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