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NASA’s Artemis splashdown will put Orion through a nail-biting test

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The Orion moonship may weigh 25 tons, but in a few days, it will skip like a slight pebble across a pond before plummeting thousands of feet through the air to its target in the Pacific Ocean.

The capsule has begun saying farewell to the moon, with just one more space flyby scheduled for Monday, Dec. 5, before heading home. Already NASA has deployed a crew to San Diego, California, to join the Navy at sea for training exercises to prepare for its unprecedented return.

NASA plans to bring Orion back with a so-called “skip entry” into Earth’s atmosphere. It’ll be the first time the U.S. space agency has ever tried the technique with a passenger spacecraft. The maneuver involves the moonship traveling at an unfathomably high speed and enduring scorching temperatures.

“Orion will come home faster and hotter than any spacecraft has before,” NASA Administrator Bill Nelson told reporters in August. “It’s going to hit the Earth’s atmosphere at 32 times the speed of sound, it’s going to dip into the atmosphere, and bleed off some of that speed, before it starts descending through the atmosphere.”

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Orion’s re-entry into Earth’s atmosphere will experience temperatures reaching 5,000 degrees Fahrenheit.
Credit: NASA

Mission leaders say the advantage is breaking up the intense G-force loads — the heavy feeling pushing against a body during extreme acceleration — into two smaller events rather than one severe episode. Though the capsule doesn’t have any people onboard now, NASA believes mastering the skip entry will keep Artemis astronauts who would experience those effects safer in the future. When humans are subjected to forces much greater than normal gravity, their hearts are put under tremendous stress, causing dizziness and sometimes blackouts.

But when the capsule comes back in about a week on Dec. 11, NASA will have to prove Orion can actually survive the ordeal. The re-entry into Earth’s atmosphere will be a nail-biting grand finale to Artemis’ maiden 25-day space voyage, with success hinging on the new Lockheed Martin-built heat shield. The hardware it’s protecting will have to withstand up to 5,000 degrees Fahrenheit, according to NASA.

Imagine an inferno half the temperature of the sun’s surface.

“That heat shield on the back end is going to show us how we’ve taken that material from the Apollo days and brought that into the 21st century,” said Kelly DeFazio, Lockheed’s Orion production director, in August. NASA hopes to put astronauts in Orion as early as 2024 for a ride around the moon. The first landing on the lunar surface would follow on Artemis III, possibly one year later.

NASA inspecting the heat shield after a test
The final objective for the Artemis I mission will be a test of the heat shield during re-entry into Earth’s atmosphere.
Credit: NASA

When Orion plunges toward Earth, it will be traveling 24,500 mph. By comparison, the Space Shuttle’s descent reached about 17,500 mph, Nelson said. That initial dip into the upper air will use the atmosphere to slow the capsule down to about 300 mph. Then, it will re-enter for a final descent, slowing down even more with parachutes.

By the time Orion hits water, it should be coasting at 20 mph. NASA will have live coverage of the event beginning at 11 a.m. ET, with the splashdown at about 12:40 p.m., on Dec. 11.


“Orion will come home faster and hotter than any spacecraft has before.”

The idea of a skip entry has existed on paper since NASA’s Apollo days half a century ago but was never attempted. Spaceships then didn’t have the navigational systems and computer power to execute it.

“Apollo was just strictly a direct entry, so that pretty much your landing site was set earlier on, when you departed the moon, with only a minor ability to adjust,” Chris Edelen, deputy manager for Orion integration, told Mashable during a briefing on Wednesday.

Apollo 12 astronauts emerging after spashdown
NASA astronaut Alan Bean emerges from the Apollo 12 spacecraft after it splashes down in the ocean in August 1969.
Credit: NASA

For Apollo missions, the spacecraft dipped into Earth’s atmosphere and then could travel up to 1,725 miles horizontally before plopping down into the ocean. A swarm of ships and rafts dispersed at sea waited on standby for the recovery operation because of such a vast range of possible places it could fall, according to the U.S. space agency.

But during a skip entry, Orion should be able to fly over 5,500 miles beyond the point it initially pokes into the upper air, giving the capsule more control over where it ultimately splashes down. NASA gets that extra wiggle room by bouncing back out of the atmosphere, where there is little drag on the spacecraft.

“One of the major advances with Artemis is that the spacecraft has the ability…to steer up and out of a denser part of the atmosphere, glide farther downrange or less downrange, so that you can pick the best landing site,” Edelen said.

NASA and Navy practicing a recovery operation for Orion
The U.S. Navy and NASA will work together to recover Artemis I’s Orion spacecraft after it splashes down in the Pacific Ocean on Dec. 11, 2022.
Credit: NASA / Tony Gray
Recovering Orion during a 2014 test
Orion is expected to return to Earth about 50 miles off the coast of San Diego, California.
Credit: NASA / Kim Shiflett

The goal is to drop Orion into the water closer to the U.S. coastline, allowing crews to get to weary returning astronauts quicker and reduce the number of boats, helicopters, and divers needed to get the job done.

Most Apollo moon missions concluded with re-entries into Earth’s atmosphere that put astronauts through the wringer of 6Gs, or six times the normal force of gravity. Apollo 16, the second to last crewed moon mission, had the highest G-level, tipping just over 7Gs.

If all goes according to plan, the three test dummies in Orion — Commander Moonikin Campos, Helga, and Zohar — will instead face two rounds of 4G-level forces. That’s a little more intense than what carnival-goers might experience on a spinning Gravitron, the superfast centrifuge ride that pins people against the wall with about 3.2 times the normal force of gravity.

Perhaps it’s a blessing the two female mannequins aren’t wearing helmets. As limbless torsos, they’d have a hard time hanging onto their hats.

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Rare ‘big fuzzy green ball’ comet visible in B.C. skies, a 50000-year sight

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In the night sky, a comet is flying by Earth for the first time in 50,000 years.

Steve Coleopy, of the South Cariboo Astronomy Club, is offering some tips on how to see it before it disappears.

The green-coloured comet, named C/2022 E3 (ZTF), is not readily visible to the naked eye, although someone with good eyesight in really dark skies might be able to see it, he said. The only problem is it’s getting less visible by the day.

“Right now the comet is the closest to earth and is travelling rapidly away,” Coleopy said, noting it is easily seen through binoculars and small telescopes. “I have not been very successful in taking a picture of it yet, because it’s so faint, but will keep trying, weather permitting.”

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At the moment, the comet is located between the bowl of the Big Dipper and the North Star but will be moving toward the Planet Mars – a steady orange-coloured point of light- in the night sky over the next couple of weeks, according to Coleopy.

“I have found it best to view the comet after 3:30 in the morning, after the moon sets,” he said. “It is still visible in binoculars even with the moon still up, but the view is more washed out because of the moonlight.”

He noted the comet looks like a “big fuzzy green ball,” as opposed to the bright pinpoint light of the stars.

“There’s not much of a tail, but if you can look through the binoculars for a short period of time, enough for your eyes to acclimatize to the image, it’s quite spectacular.”

To know its more precise location on a particular evening, an internet search will produce drawings and pictures of the comet with dates of where and when the comet will be in each daily location.

Coleopy notes the comet will only be visible for a few more weeks, and then it won’t return for about 50,000 years.


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Extreme species deficit of nitrogen-converting microbes in European lakes

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Sampling of Lake Constance water from 85 m depth, in which ammonia-oxidizing archaea make up as much as 40% of all microorganisms

Dr. David Kamanda Ngugi, environmental microbiologist at the Leibniz Institute DSMZ

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Leibniz Institute DSMZ

 

An international team of researchers led by microbiologists from the Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures GmbH in Braunschweig, Germany, shows that in the depths of European lakes, the detoxification of ammonium is ensured by an extremely low biodiversity of archaea. The researchers recently published their findings in the prestigious international journal Science Advances. The team led by environmental microbiologists from the Leibniz Institute DSMZ has now shown that the species diversity of these archaea in lakes around the world ranges from 1 to 15 species. This is of particularly concern in the context of global biodiversity loss and the UN Biodiversity Conference held in Montreal, Canada, in December 2022. Lakes play an important role in providing freshwater for drinking, inland fisheries, and recreation. These ecosystem services would be at danger from ammonium enrichment. Ammonium is an essential component of agricultural fertilizers and contributes to its remarkable increase in environmental concentrations and the overall im-balance of the global nitrogen cycle. Nutrient-poor lakes with large water masses (such as Lake Constance and many other pre-alpine lakes) harbor enormously large populations of archaea, a unique class of microorganisms. In sediments and other low-oxygen environments, these archaea convert ammonium to nitrate, which is then converted to inert dinitrogen gas, an essential component of the air. In this way, they contribute to the detoxification of ammonium in the aquatic environment. In fact, the species predominant in European lakes is even clonal and shows low genetic microdiversity between different lakes. This low species diversity contrasts with marine ecosystems where this group of microorganisms predominates with much greater species richness, making the stability of ecosystem function provided by these nitrogen-converting archaea potentially vulnerable to environmental change.

Maintenance of drinking water quality
Although there is a lot of water on our planet, only 2.5% of it is fresh water. Since much of this fresh water is stored in glaciers and polar ice caps, only about 80% of it is even accessible to us humans. About 36% of drinking water in the European Union is obtained from surface waters. It is therefore crucial to understand how environmental processes such as microbial nitrification maintain this ecosystem service. The rate-determining phase of nitrification is the oxidation of ammonia, which prevents the accumulation of ammonium and converts it to nitrate via nitrite. In this way, ammonium is prevented from contaminating water sources and is necessary for its final conversion to the harmless dinitrogen gas. In this study, deep lakes on five different continents were investigated to assess the richness and evolutionary history of ammonia-oxidizing archaea. Organisms from marine habitats have traditionally colonized freshwater ecosystems. However, these archaea have had to make significant changes in their cell composition, possible only a few times during evolution, when they moved from marine habitats to freshwaters with much lower salt concentrations. The researchers identified this selection pressure as the major barrier to greater diversity of ammonia-oxidizing archaea colonizing freshwaters. The researchers were also able to determine when the few freshwater archaea first appeared. Ac-cording to the study, the dominant archaeal species in European lakes emerged only about 13 million years ago, which is quite consistent with the evolutionary history of the European lakes studied.

Slowed evolution of freshwater archaea
The major freshwater species in Europe changed relatively little over the 13 million years and spread almost clonally across Europe and Asia, which puzzled the researchers. Currently, there are not many examples of such an evolutionary break over such long time periods and over large intercontinental ranges. The authors suggest that the main factor slowing the rapid growth rates and associated evolutionary changes is the low temperatures (4 °C) at the bottom of the lakes studied. As a result, these archaea are restricted to a state of low genetic diversity. It is unclear how the extremely species-poor and evolutionarily static freshwater archaea will respond to changes induced by global climate warming and eutrophication of nearby agricultur-al lands, as the effects of climate change are more pronounced in freshwater than in marine habitats, which is associated with a loss of biodiversity.

Publication: Ngugi DK, Salcher MM, Andre A-S, Ghai R., Klotz F, Chiriac M-C, Ionescu D, Büsing P, Grossart H-S, Xing P, Priscu JC, Alymkulov S, Pester M. 2022. Postglacial adaptations enabled coloniza-tion and quasi-clonal dispersal of ammonia oxidizing archaea in modern European large lakes. Science Advances: https://www.science.org/doi/10.1126/sciadv.adc9392

Press contact:
PhDr. Sven-David Müller, Head of Public Relations, Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures GmbH
Phone: ++49 (0)531/2616-300
Mail: press@dsmz.de

About the Leibniz Institute DSMZ
The Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures is the world’s most diverse collection of biological resources (bacteria, archaea, protists, yeasts, fungi, bacteriophages, plant viruses, genomic bacterial DNA as well as human and animal cell lines). Microorganisms and cell cultures are collected, investigated and archived at the DSMZ. As an institution of the Leibniz Association, the DSMZ with its extensive scientific services and biological resources has been a global partner for research, science and industry since 1969. The DSMZ was the first registered collection in Europe (Regulation (EU) No. 511/2014) and is certified according to the quality standard ISO 9001:2015. As a patent depository, it offers the only possibility in Germany to deposit biological material in accordance with the requirements of the Budapest Treaty. In addition to scientific services, research is the second pillar of the DSMZ. The institute, located on the Science Campus Braunschweig-Süd, accommodates more than 82,000 cultures and biomaterials and has around 200 employees. www.dsmz.de

PhDr. Sven David Mueller, M.Sc.
Leibniz-Institut DSMZ
+49 531 2616300
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Scientists are closing in on why the universe exists

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Particle astrophysicist Benjamin Tam hopes his work will help us understand a question. A very big one.

“The big question that we are trying to answer with this research is how the universe was formed,” said Tam, who is finishing his PhD at Queen’s University.

“What is the origin of the universe?”

And to answer that question, he and dozens of fellow scientists and engineers are conducting a multi-million dollar experiment two kilometres below the surface of the Canadian Shield in a repurposed mine near Sudbury, Ontario.

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Ten thousand light-sensitive cameras send data to scientists watching for evidence of a neutrino bumping into another particle. (Tom Howell/CBC)

The Sudbury Neutrino Observatory (SNOLAB) is already famous for an earlier experiment that revealed how neutrinos ‘oscillate’ between different versions of themselves as they travel here from the sun.

This finding proved a vital point: the mass of a neutrino cannot be zero. The experiment’s lead scientist, Arthur McDonald, shared the Nobel Prize in 2015 for this discovery.

The neutrino is commonly known as the ‘ghost particle.’ Trillions upon trillions of them emanate from the sun every second. To humans, they are imperceptible except through highly specialized detection technology that alerts us to their presence.

Neutrinos were first hypothesized in the early 20th century to explain why certain important physics equations consistently produced what looked like the wrong answers. In 1956, they were proven to exist.

A digital image of a sphere that is blue and transparent with lines all over.
The neutrino detector is at the heart of the SNO+ experiment. An acrylic sphere containing ‘scintillator’ liquid is suspended inside a larger water-filled globe studded with 10,000 light-sensitive cameras. (Submitted by SNOLOAB)

Tam and his fellow researchers are now homing in on the biggest remaining mystery about these tiny particles.

Nobody knows what happens when two neutrinos collide. If it can be shown that they sometimes zap each other out of existence, scientists could conclude that a neutrino acts as its own ‘antiparticle’.

Such a conclusion would explain how an imbalance arose between matter and anti-matter, thus clarifying the current existence of all the matter in the universe.

It would also offer some relief to those hoping to describe the physical world using a model that does not imply none of us should be here.

A screengrab of two scientists wearing white hard hat helmets, clear googles and blue safety suits standing on either side of CBC producer holding a microphone. All three people are laughing.
IDEAS producer Tom Howell (centre) joins research scientist Erica Caden (left) and Benjamin Tam on a video call from their underground lab. (Screengrab: Nicola Luksic)

Guests in this episode (in order of appearance):

Benjamin Tam is a PhD student in Particle Astrophysics at Queen’s University.

Eve Vavagiakis is a National Science Foundation Astronomy and Astrophysics Postdoctoral Fellow in the Physics Department at Cornell University. She’s the author of a children’s book, I’m A Neutrino: Tiny Particles in a Big Universe.

Blaire Flynn is the senior education and outreach officer at SNOLAB.

Erica Caden is a research scientist at SNOLAB. Among her duties she is the detector manager for SNO+, responsible for keeping things running day to day.


*This episode was produced by Nicola Luksic and Tom Howell. It is part of an on-going series, IDEAS from the Trenches, some stories are below.

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