Off-Earth Manufacturing: Using Local Resources To Build a New Home on Another World

By EUROPEAN SPACE AGENCY (ESA) JANUARY 3, 2022

A vision of a future Moon base that could be produced and maintained using 3D printing. Credit: RegoLight, visualisation: Liquifer Systems Group, 2018

Humanity is heading back to the Moon, and this time, we’re planning to stay. But for long-term space missions, astronauts would need infrastructure to live and work, to move around, to communicate with Earth, and to produce oxygen and water vital for survival. Taking all this infrastructure from Earth would likely be prohibitively expensive. Instead, we need to figure out how to make it on site. ESA Discovery & Preparation has supported many studies to explore how we can do this.

Using local materials to build infrastructure and produce amenities is known as in-situ resource utilization (ISRU). Past research in this area has explored and demonstrated fundamental ISRU concepts using a combination of resources found on the exploration site and materials brought from Earth.

By testing the market for transport services to the Moon, ESA aims to push the limits of technology and create new models of space business. Credit: ESA

ISRU is needed to build a habitat that shields astronauts from harsh environments including thin or non-existent atmospheres, extreme temperatures, intense radiation, and even micrometeoroids. It would enable us to build roads to move around the surface, and launch and landing pads for traveling to and from Earth. It could be used to produce equipment that can generate and store energy for producing electricity, as well as antenna towers for communication. And it could produce huge amounts of water and oxygen for keeping astronauts alive and creating propellants for traveling around and eventually coming back to Earth.

Discovery & Preparation activities

In 1999, one of the first ISRU-related Discovery & Preparation studies focused on propulsion and power systems, assessing the needs for advanced propulsion in the current century. The study concluded that ISRU could reduce the costs of missions to Mars whilst increasing our capabilities, but that research and development in ISRU technologies should begin right away.

And so, in coordination with all ESA programs, research continued. A study completed in 2000 focused on the power systems required for future space exploration, including designing an ISRU chemical plant to produce propellant, chemicals for life support, and fuel for surface activities.

A close-up view of GOCE’s ion-propulsion assembly. Credit: ESA /AOES Medialab

Other studies happening at the same time took a broader look at long-term space exploration, with one considering what architectures and technologies would be required for Mars exploration. The study investigated the possibility of producing propellant and fluids necessary for crew survival – including nitrogen, oxygen, hydrogen and water – from the Martian atmosphere and soil. Another study on the survivability and adaptability of humans to long-duration interplanetary and planetary environments also found that ISRU could be particularly useful for producing propellants and life support consumables.

Fast forwarding 13 years, the technology had developed enough to explore more specific ISRU concepts, including a system to collect and store carbon dioxide from the Martian atmosphere and deliver it to a propulsion system. The study, carried out by Airbus, suggested ways in which dust and water could be removed from the carbon dioxide, as well as how it could be liquified for storage.

Over the last few years, Discovery & Preparation has supported more research into building infrastructure using lunar soil and more specific methods of energy generation and storage; a recent study explored how lunar regolith could be used to store heat and provide electricity for astronauts, rovers, and landers.

Setting up a future lunar base could be made much simpler by using a 3D printer to build it from local materials. Industrial partners including renowned architects Foster+Partners joined ESA to test the feasibility of 3D printing using lunar soil. Credit: ESA/Foster + Partners

One study explored how lunar analog facilities could support the development of ISRU technologies, including testing the excavation and processing of local materials, as well as how these materials could be used to build structures using processes like 3D printing.

Another confirmed the suitability of lunar soil as a building material, selected a suitable process for printing structures from it, and even designed a printable habitat. And a third recently went one step further and explored how any necessary structures, equipment, and spare parts could be 3D printed using lunar regolith, even selecting which specific printing processes would work best.

As an alternative to existing 3D printing technologies, a 2019 study looked into turning lunar soil into fibers to build strong structures. The researchers produced a sample of material to show that it is possible to use this process to make structures that are locally impermeable.

A set of Discover & Preparation studies recently explored and defined ESA’s lunar IRSU demonstration mission, which aims to prove by 2025 that producing water or oxygen on the Moon is possible. These studies looked into the system that would actually produce the water and oxygen, proposing a package that extracts oxygen from the soil and uses it to produce water, using a ‘carbo-thermal reactor’. Another explored how the system could rely on a lander as a power supply and a third investigated how it could communicate with Earth.

What else is ESA doing?

To implement the lunar ISRU demonstration mission, ESA intends to procure mission-enabling services from the commercial sector, including payload delivery, communication, and operations services. In doing so, ESA will both leverage on and further nurture existing commercial initiatives that may find widespread applications in a future lunar exploration scenario.

A computer model of Luna-27, which will fly to the Moon’s south pole. Credit: Roscosmos

ESA is also currently working on the PROSPECT mission, which will access and assess potential resources on the Moon to prepare for the technologies that may be used to extract these resources in the future. PROSPECT will drill beneath the Moon’s surface near its South Pole and extract samples expected to contain frozen water and other chemicals that can become trapped at extremely low temperatures. The drill will then pass the samples to a chemical laboratory where they will be heated to extract these chemicals. The mission will operate as part of the Russian-led Luna-27 mission and will test processes that could be applied to resource extraction in the future.

To support the ambition to have a human presence on the Moon sustained by local resources by 2040, in May 2019, ESA published its Space Resources Strategy. The strategy considers what we need to discover and develop to support sustainable space exploration. The strategy covers the period up to 2030, by which time the potential of lunar resources will have been established through measurements at the Moon, key technologies will have been developed and demonstrated and a plan for their introduction into international mission architectures will have been defined. Following the publication of the strategy, ESA hosted a workshop to identify the next steps needed to make space resource utilization a reality.

Producing oxygen and metal out of simulated moondust inside ESA’s Materials and Electrical Components Laboratory. Credit: ESA–A. Conigili

In 2020, ESA set up a prototype plant to produce oxygen out of simulated moondust. Removing the oxygen from lunar soil leaves various metals; another line of research, therefore, is to see what are the most useful alloys that could be produced from them, and how they could be used on the Moon. The ultimate aim would be to design a ‘pilot plant’ that could operate sustainably on the Moon, with the first technology demonstration targeted for the mid-2020s.

What are other space agencies doing in this area?

NASA’s Lunar Reconnaissance Orbiter already indicated the presence of water ice buried under the lunar soil at certain locations. The orbiter launched with the Lunar CRater Observation and Sensing Satellite that was released from the orbiter and impacted the Moon; observations of the resulting 16-kilometer-high plume showed the chemical make-up of the lunar surface.

The US Agency is also developing several CubeSat orbital missions that will visit the Moon. Lunar Flashlight, LunaH-MAP, and Lunar IceCube will aim to find out how much water ice there is and where exactly it can be found.

Artist’s impression of NASA’s Mars Perseverance rover. Credit: NASA/JPL-Caltech

NASA’s first Mars lander, Viking, returned important data about the Martian atmosphere, revealing that it is made up of 95.9 percent carbon dioxide. Based on this discovery and information returned by subsequent robotic missions, the Agency has developed technologies to convert Mars’ atmospheric carbon dioxide into oxygen to benefit human missions to the red planet. Recently, NASA selected the Mars Oxygen In-Situ Resource Utilization Experiment, or MOXIE, as one of seven instruments on the Mars Perseverance rover.

Volatiles are substances that vaporize easily and could be a source of water on the Moon. Together with other space agencies, NASA is conducting an international coordination of lunar polar volatiles exploration to increase scientific knowledge, determine the viability of volatiles as potential resources, and to use the Moon as a proving ground for Mars ISRU technologies.

Future China National Space Administration missions are also expected to target lunar polar volatiles as potential resources. China’s vision of an international lunar research station, to be established initially as a robotic facility for science and research during the late 2020s and early 2030s may provide an early opportunity for lunar resources to be utilized.

The Russian space agency, Roscosmos, is working with ESA on the series of three Luna missions, including Luna-27, which will host ESA’s PROSPECT package. The mission will target measurements in the polar region of the Moon, focusing on cold trapped volatiles that may be found there.

What’s next at ESA?

Through its Open Space Innovation Platform (OSIP), ESA sought ideas on enabling technologies for in-situ construction, manufacturing, and maintenance of infrastructure and hardware to support long-term exploration of a planetary body.

The proposed ideas support the construction of habitats, mobility infrastructure (e.g. roads and landing pads), ancillary infrastructure (e.g. for communication and energy generation and storage), and hardware (e.g. tools, interior equipment, machinery and clothing).

An idea submitted to the Open Space Innovation Platform (OSIP) proposed that orbital debris could be used for in-situ resource manufacturing on the Moon. Credit: ESA/Orbit Recycling

Ideas include many novel methods for melting and 3D printing lunar soil, making solar cells from lunar soil, optimizing energy storage, finding methods to grow plants from organic waste without needing soil, using lunar soil to build crop-friendly greenhouses, and building infrastructure using space debris. Many of the ideas are now being implemented by ESA as studies, co-funded research projects or early technology development projects. To find out more, visit the results section of this call for ideas.

The use of space resources for exploration is now within reach thanks to advances in our knowledge and understanding of the Moon and asteroids, increased international and private sector engagement in space technologies, and the emergence of new technologies.

Developing technologies and methods to use local resources to support future astronauts remains a challenge, but in doing so we are stimulating innovation on Earth through technology needs as well as new approaches to managing limited resources. This will hopefully help us find new ways to address global challenges and generate near to mid-term economic returns for terrestrial industries.

Extinct species of fish reintroduced into its native habitat in Mexico

Locals and international organizations worked together to make it happen.

 by Alexandru Micu
January 3, 2022


A little river in Mexico is the site of one of 2021’s most heartwarming tales — the reintroduction of a species that had gone extinct in the wild.

Tequila splitfin (Zoogoneticus tequila). Image via Wikimedia.

We often hear stories about animals going extinct, and they’re always heartbreaking. But, every so often, we get to hear of the reverse: a species that had gone extinct, being reintroduced into the wild. The waters of the Teuchitlán, a river in Mexico that flows near a town bearing the same name, can now boast the same tale.

Efforts by local researchers, conservationists, and citizens, with international support, have successfully reintroduced the tequila splitfin (Zoogoneticus tequila), a tiny fish that only lived in the Teuchitlán river but had gone extinct during the 1990s, to the wild.

Re-fishing

In the 1990s, populations of the tequila splitfin began to dwindle in the Teuchitlán river. Eventually, it vanished completely.

Omar Domínguez, one of the researchers behind the program that reintroduced the species, and a co-authored of the paper describing the process, was a university student at the time and worried about the fish’s future. Pollution, human activity, and invasive, non-native species were placing great pressure on the tequila splitfin.

Now a 47-year-old researcher at the University of Michoacán, he recounts that then only the elderly in Teuchitlán remembered the fish — which they called gallito (“little rooster”) because of its brightly-colored, orange tail.

Conservation efforts started in 1998 when a team from the Chester Zoo in England, alongside members from other European institutions, arrived with several pairs of tequila splitfin from the aquariums of collectors and set up a lab to help preserve the species.

The first few years were spent reproducing the fish in aquariums. Reintroducing these to the river directly was deemed to be too risky. So Domínguez and his colleagues built an artificial pond on-site, in which the fish could breed in semi-captivity. The then-40 pairs of tequila splitfins were placed in this pond in 2012, and by 2014 they had multiplied to around 10,000 individuals.

By now, their results gave all the organizations involved in the effort (various zoos and wildlife conservation groups from Europe, the United States, and the United Arab Emirates) enough confidence to fund further experimentation. So the team set their sights on the river itself. Here, they studied the species’ interactions with local predators, parasites, microorganisms, and how they fit into the wider ecosystem of the area.

Then, they placed some of the tequila splitfins back into the river — inside floating cages. This step, too, was a marked success, and the fish multiplied quickly inside the cages. When their numbers grew large enough, around late 2017, the researchers marked the individual fish and set them free. In the next six months, their population increased by 55%, the authors report. The fish are still going strong, they add: in December 2021, they were seen inhabiting a new area of the river, where they were completely extinct in the past.

It’s not just about giving a species a new lease on life, the team explains. Their larger goal was to restore the natural equilibrium of the river’s ecosystem. Although there is no hard data on environmental factors in the past to compare with, Domínguez is confident that the river’s overall health has improved. Its waters are cleaner, the number of invasive species has declined, and cattle are no longer allowed to drink directly from the river in some areas.

Local communities were instrumental in the conservation effort.

“When I started the environmental education program I thought they were going to turn a deaf ear to us — and at first that happened,” Domínguez said.

However, the conservationists made sustained efforts to educate the locals through puppet shows, games, and educational materials, and presentations about zoogoneticus tequila. Among others, citizens were told about the ecological role of the species, and the part it plays in controlling dengue-spreading mosquitoes.

The tequila splitfin is currently listed as endangered on the IUCN’s red list.

The paper “Progress in the reintroduction program of the tequila splitfin in the springs of Teuchitlán, Jalisco, Mexico” has been published online by the IUCN CTSG (Conservation Translocation Specialist Group). An update on the project has been published in the magazine Amazonas.




Alexandru Micu
Stunningly charming pun connoisseur, I have been fascinated by the world around me since I first laid eyes on it. Always curious, I'm just having a little fun with some very serious science.

© 2007-2019 ZME Science - Not exactly rocket science. All Rights Reserved.

A starfish-shaped soft robot that creeps, changes its color, and self-heals broken parts

by Wiley

Credit: Wiley

Natural camouflage is one of nature's most interesting traits. Materials scientists have now developed a material that can mimic the camouflage capabilities of marine mollusks. They created a starfish-shaped soft robot that responds to heat and pressure with deformation, movement, and color changes. Cut-off tentacles can be welded together, and the material can be fully recycled, they write in the journal Angewandte Chemie.

Octopuses, jellyfish, and starfish are capable of natural camouflage; that is, they can quickly change their colors or shapes to match the background. A research team led by Quan Li from Southeast University, China, has now created a soft material that can mimic such traits. As an underlying material, they chose a liquid crystal elastomer that changes phases at different temperatures. When heated up, the oriented liquid crystal molecules of the elastomer lose ordering, causing the material part to shrink.

The researchers used this shrinking effect to enable a soft robot to "crawl." For this purpose, they molded the polymer material in the shape of a starfish and added an infrared-sensitive dye to the underside of one of the tentacles. This modified site contracted when heated up by a photothermal effect resulting from near-infrared irradiation, and expanded when cooled down. Since only one arm received the light stimulus, the starfish robot slowly moved over the surface, pushed by the contracting–expanding tentacle like a caterpillar.

The starfish soft robot was capable of changing its color. The researchers integrated a cross-linker in the material—a molecular dye linking polymer strands. However, the dynamic covalent cross-linking system used here was made to break easily. During heating and under pressure, its molecular parts separated, and the previously yellowish dye molecule turned red. "Similar to the natural camouflage effect of a starfish," the authors said.

Finally, the starfish robot also demonstrated self-healing and even recycling qualities. When the researchers cut off a tentacle, it healed seamlessly after the parts were heated up again. The same thing occurred when the whole robot was cut to pieces. Molding it again into a starfish shape, the researchers regained a new, soft robot with properties that were intact.

According to the authors, the key to this multiple adaptation capability was the integration of the cross-linking dye molecule, tetraarylsuccinonitrile, which could perform several functions simultaneously. It acted as a light-absorbing chromophore, and it provided dynamic covalent bonding to the elastomeric network. The authors suggest use of such biomimetic soft materials with thermal and mechanochromic properties (color change due to heat and pressure) in biomimetic robots, sensors, and for artificial camouflage.Watch these tube-shaped robots roll up stairs, carry carts, and race one another

More information: Zhongcheng Liu et al, Thermo‐ and Mechanochromic Camouflage and Self‐Healing in Biomimetic Soft Actuators Based on Liquid Crystal Elastomers, Angewandte Chemie International Edition (2021). DOI: 10.1002/anie.20211575

Provided by Wiley 

Study finds reduced microbial diversity in guts of wild bears that eat human food

by Matt Shipman, North Carolina State University

Credit: Tom Gillman

A recent study suggests that eating human food has a pronounced effect on the microbiome of black bears. Specifically, researchers from North Carolina State University and Northern Michigan University found that wild bears who consumed a lot of processed foods had far less diversity in the microbial ecosystems of their guts.

"We know a 'western' diet can reduce microbial diversity in the guts of humans, mice and other species, which can have an adverse effect on their health," says Erin McKenney, co-author of the study and an assistant professor of applied ecology at NC State. "We want to know if the same is true for wildlife, particularly given the increasing overlap between where people live and where wildlife lives. One possibility our work here raises is that if wildlife begin consuming human foods, it may affect their ability to derive as much nutrition from their traditional, wild diet if they stop eating human foods."

"One step toward seeing if the same is true for wildlife is to assess the impact that human foods have on the gut microbiome of wild mammals," says Sierra Gillman, first author of the study and a Ph.D. student at the University of Washington. "In this particular study, we wanted to know how human foods influence the gut microbiome of black bears." Gillman did the work while a grad student at NMU.

The researchers focused the study on Michigan, which allows hunters to "bait" bears by leaving out large quantities of human food, such as sugary cereals and candy. Hunters will bait specific sites for weeks or months to lure bears to a specific area on a regular basis. As a result, some bears have a diet that is rich in human junk food for an extended period of time.

To collect samples from the wild bear population, the researchers worked with guides who lead scheduled trips with hunters in the Upper Peninsula of Michigan. The guides collected samples from bears that were harvested when the guides went on their regularly scheduled trips with hunters. Specifically, the guides followed a detailed protocol for retrieving hair samples and two gut samples. The gut samples were from the jejunum, which is the middle section of the small intestine, and the colon, which is also called the large intestine. Ultimately, the researchers were able to retrieve samples from 35 legally-harvested bears.

The researchers processed the gut samples to identify both what kinds of microbes were present in each bear's microbiome as well as how many of each type of microbe was present.

The researchers also conducted a carbon isotope analysis of the bear's hair, which gave them an assessment of each bear's long-term diet. More specifically, the analysis told researchers the extent to which each bear was consuming sugar and corn, which are more likely to be found in processed foods.

When analyzing the data, the researchers looked at two measures of gut biodiversity. First they look at the total number of different species present. Second, they looked at a measure called Faith's phylogenetic diversity, which looks at how many different types of species are present.

"Basically, Faith's phylogenetic diversity assesses how many branches of the bacterial family tree are represented," Gillman says.

Both measures of gut biodiversity were substantially lower in bears that had been eating more processed foods.

"Essentially, we found that the more human food black bears eat, and the longer they eat it, the less diverse their gut microbiomes," Gillman says

"Sugar is very easy to digest," McKenney says. "Lots of bacteria can consume it. In practical terms, that means processed human foods actually have less food available for bacteria that specialize in breaking down fiber or other microaccessible carbohydrates. Those bacterial specialists have trouble competing with the other bacteria for sugar, and their niche in the food web isn't sustainable if bears don't eat enough of their traditional diet. We think that's one of the mechanisms for reducing gut microdiversity.

"And if the gut biodiversity suffers when bears begin consuming more human food, that raises the possibility that it would be more difficult for bears to derive as much nutritional value from non-human foods if they return to a 'wild' diet," McKenney says. "Basically, it's not clear how quickly microbial species that break down fiber, etc., would return."

"Now that we've identified this association between eating human food and microbial biodiversity, we need to do additional work to determine what this means for the health of these animals—and potentially other animals," Gillman says.

"Many hunters use camera traps to monitor their bait sites, and people we've worked with have told us that they see a wide variety of species—raccoons, fishers, martens, deer, hares—eating the bear bait," says Diana Lafferty, co-author of the paper and an assistant professor of wildlife ecology at NMU.

"It's not clear how baiting might be affecting the microbiomes or health of other wildlife that is taking advantage of the free food. As we think about conservation, assessing the impact of our activities on diversity may need to extend to protecting microbial diversity. Because the evidence increasingly suggests that many of these microbial organisms are critical to the health of wildlife species. How does baiting fit into that? Those are issues I think we'll need to explore."

The paper, "Human-provisioned foods reduce gut microbiome diversity in American black bears (Ursus americanus)," is published in the Journal of Mammalogy.

Black bear gut biome surprisingly simple, scientists say

More information: Sierra J Gillman et al, Human-provisioned foods reduce gut microbiome diversity in American black bears (Ursus americanus), Journal of Mammalogy (2021). DOI: 10.1093/jmammal/gyab154

Journal information: Journal of Mammalogy 

Provided by North Carolina State University 

Predator interactions chiefly determine where Prochlorococcus microbes thrive

by Jennifer Chu, Massachusetts Institute of Technology

Credit: CC0 Public Domain

Prochlorococcus are the smallest and most abundant photosynthesizing organisms on the planet. A single Prochlorococcus cell is dwarfed by a human red blood cell, yet globally the microbes number in the octillions and are responsible for a large fraction of the world's oxygen production as they turn sunlight into energy.

Prochlorococcus can be found in the ocean's warm surface waters, and their population drops off dramatically in regions closer to the poles. Scientists have assumed that as with many marine species, Prochlorococcus's range is set by temperature: The colder the waters, the less likely the microbes are to live there.

But MIT scientists have found that where the microbe lives is not determined primarily by temperature. While Prochlorococcus populations do drop off in colder waters, it's a relationship with a shared predator, and not temperature, that sets the microbe's range. These findings, published today in the Proceedings of the National Academy of Sciences, could help scientists predict how the microbes' populations will shift with climate change.

"People assume that if the ocean warms up, Prochlorococcus will move poleward. And that may be true, but not for the reason they're predicting," says study co-author Stephanie Dutkiewicz, senior research scientist in MIT's Department of Earth, Atmospheric and Planetary Sciences (EAPS). "So, temperature is a bit of a red herring."

Dutkiewicz's co-authors on the study are lead author and EAPS Research Scientist Christopher Follett, EAPS Professor Mick Follows, François Ribalet and Virginia Armbrust of the University of Washington, and Emily Zakem and David Caron of the University of Southern California at Los Angeles.

Temperature's collapse

While temperature is thought to set the range of Prochloroccus and other phytoplankton in the ocean, Follett, Dutkiewicz, and their colleagues noticed a curious dissonance in data.

The team examined observations from several research cruises that sailed through the northeast Pacific Ocean in 2003, 2016, and 2017. Each vessel traversed different latitudes, sampling waters continuously and measuring concentrations of various species of bacteria and phytoplankton, including Prochlorococcus.

The MIT team used the publicly archived cruise data to map out the locations where Prochlorococcus noticeably decreased or collapsed, along with each location's ocean temperature. Surprisingly, they found that Prochlorococcus's collapse occurred in regions of widely varying temperatures, ranging from around 13 to 18 degrees Celsius. Curiously, the upper end of this range has been shown in lab experiments to be suitable conditions for Prochlorococcus to grow and thrive.

"Temperature itself was not able to explain where we saw these drop-offs," Follett says.

Follett was also working out an alternate idea related to Prochlorococcus and nutrient supply. As a byproduct of its photosynthesis, the microbe produces carbohydrate—an essential nutrient for heterotrophic bacteria, which are single-celled organisms that do not photosynthesize but live off the organic matter produced by phytoplankton.

"Somewhere along the way, I wondered, what would happen if this food source Prochlorococcus was producing increased? What if we took that knob and spun it?" Follett says.

In other words, how would the balance of Prochlorococcus and bacteria shift if the bacteria's food increased as a result of, say, an increase in other carbohydrate-producing phytoplankton? The team also wondered: If the bacteria in question were about the same size as Prochlorococcus, the two would likely share a common grazer, or predator. How would the grazer's population also shift with a change in carbohydrate supply?

"Then we went to the whiteboard and started writing down equations and solving them for various cases, and realized that as soon as you reach an environment where other species add carbohydrates to the mix, bacteria and grazers grow up and annihilate Prochlorococcus," Dutkiewicz says.

Nutrient shift

To test this idea, the researchers employed simulations of ocean circulation and marine ecosystem interactions. The team ran the MITgcm, a general circulation model that simulates, in this case, the ocean currents and regions of upwelling waters around the world. They overlaid a biogeochemistry model that simulates how nutrients are redistributed in the ocean. To all of this, they linked a complex ecosystem model that simulates the interactions between many different species of bacteria and phytoplankton, including Prochlorococcus.

When they ran the simulations without incorporating a representation of bacteria, they found that Prochlorococcus persisted all the way to the poles, contrary to theory and observations. When they added in the equations outlining the relationship between the microbe, bacteria, and a shared predator, Prochlorococcus's range shifted away from the poles, matching the observations of the original research cruises.

In particular, the team observed that Prochlorococcus thrived in waters with very low nutrient levels, and where it is the dominant source of food for bacteria. These waters also happen to be warm, and Prochlorococcus and bacteria live in balance, along with their shared predator. But in more nutrient-rich environments, such as polar regions, where cold water and nutrients are upwelled from the deep ocean, many more species of phytoplankton can thrive. Bacteria can then feast and grow on more food sources, and in turn feed and grow more of its shared predator. Prochlorococcus, unable to keep up, is quickly decimated.

The results show that a relationship with a shared predator, and not temperature, sets Prochlorococcus's range. Incorporating this mechanism into models will be crucial in predicting how the microbe—and possibly other marine species—will shift with climate change.

"Prochlorococcus is a big harbinger of changes in the global ocean," Dutkiewicz says. "If its range expands, that's a canary—a sign that things have changed in the ocean by a great deal."

"There are reasons to believe its range will expand with a warming world," Follett adds." But we have to understand the physical mechanisms that set these ranges. And predictions just based on temperature will not be correct."By 2100, climate change could alter key microbial interactions in the ocean

More information: Trophic interactions with heterotrophic bacteria limit the range of Prochlorococcus, Proceedings of the National Academy of Sciences (2022). DOI: 10.1073/pnas.2110993118.

Journal information: Proceedings of the National Academy of Sciences 

Provided by Massachusetts Institute of Technology 

The significant roles of anthropogenic aerosols on surface temperature under carbon neutrality

by Li Yuan, Chinese Academy of Sciences

Credit: CC0 Public Domain

A new study finds that in the near future, the warming effect of anthropogenic aerosol reduction will superimpose on the cooling effect caused by the CO2 reduction, leading to greater surface temperature increase, delayed start of temperature reduction, and a decelerated cooling rate.

This aerosol effect will not only extend the time required to achieve Paris Agreement targets, but also trigger a long-term cooling trend in the subpolar North Atlantic that is distinct from other regions.

The study was published in Science Bulletin. It was completed by Dr. Ma Xiaofan, Prof. Huang Gang, and Prof. Cao Junji from the Institute of Atmospheric Physics, Chinese Academy of Sciences.

Though atmospheric CO2 makes an impact on surface temperature, the role of aerosols on the spatiotemporal changes of temperature cannot be ignored.

A large reduction in anthropogenic emissions is needed to achieve carbon neutrality and the low-warming target, which means that the concentration of CO2 and aerosols in the atmosphere will jointly show a downward trend in the future.

However, the same trends in aerosols and CO2 will cause opposite radiative effects. The warming effect produced by reduced aerosols works simultaneously with the cooling effect caused by reduced CO2. In addition, aerosols can also affect the dynamic processes from the surface to the deep layer in the ocean, thereby altering regional features of ocean temperature.

To explore the impact of future reductions in anthropogenic aerosols on surface temperature, the researchers used the Community Earth System Model (CESM) to perform fixed-aerosol experiments over the 21st century under a low-emission scenario (RCP2.6) and compared the results with those in all-forcing simulations under the same scenario.

They found that the additional warming effect caused by the continued decline of aerosols in the 21st century will make the global mean surface temperature increase for a longer period of time, rather than a decrease following the reduction of CO2 (after ~2050).

They also found that under the low-emission scenario, when other regions have long-term warming trends in surface temperature, the subpolar North Atlantic (south of Greenland) shows long-term cooling trends. This phenomenon is dominated by aerosols while CO2 plays a secondary role. The regional inconsistency of temperature changes is mainly due to the weakening of the Atlantic Meridional Overturning Circulation (AMOC).

Under the reduction of anthropogenic aerosols, the AMOC continues to weaken since the beginning of the 21st century, which causes the northward heat transport in the Atlantic continue to weaken. The anomalous cold signals gradually accumulate in the subpolar North Atlantic, leading to significant cooling trends in sea surface temperatures over this region in the second half of the century. The cooling of the sea surface further induces the local ocean to absorb more heat from the atmosphere through air-sea heat flux.

"Our study indicates that when planning a specific path to achieve carbon neutrality and low-warming targets, it is necessary to consider the important role of anthropogenic aerosols on the climate system," said Prof. Huang, the corresponding author of the study.Cutting emissions makes North Atlantic focus of ocean heat uptake under global warming

More information: Xiaofan Ma et al, The significant roles of anthropogenic aerosols on surface temperature under carbon neutrality, Science Bulletin (2021). DOI: 10.1016/j.scib.2021.10.022

Provided by Chinese Academy of Sciences 

Are Black Holes and Dark Matter the Same? Astrophysicists Upend Textbook Explanations

By UNIVERSITY OF MIAMI JANUARY 3, 2022

This animation shows an artist’s rendition of the cloudy structure revealed by a study of data from NASA’s Rossi X-Ray Timing Explorer satellite. Credit: Wolfgang Steffen, UNAM

Upending textbook explanations, astrophysicists from the University of Miami, Yale University, and the European Space Agency suggest that primordial black holes account for all dark matter in the universe.

Proposing an alternative model for how the universe came to be, a team of astrophysicists suggests that all black holes—from those as tiny as a pinhead to those covering billions of miles—were created instantly after the Big Bang and account for all dark matter.

That’s the implication of a study by astrophysicists at the University of Miami, Yale University, and the European Space Agency that suggests that black holes have existed since the beginning of the universe ­­and that these primordial black holes could be as-of-yet unexplained dark matter. If proven true with data collected from this month’s launch of the James Webb Space Telescope, the discovery may transform scientific understanding of the origins and nature of two cosmic mysteries: dark matter and black holes.

“Our study predicts how the early universe would look if, instead of unknown particles, dark matter was made by black holes formed during the Big Bang—as Stephen Hawking suggested in the 1970s,” said Nico Cappelluti, an assistant professor of physics at the University of Miami and first author of the study slated for publication in The Astrophysical Journal.

“This would have several important implications,” continued Cappelluti, who this year expanded the research he began at Yale as the Yale Center for Astronomy and Astrophysics Prize Postdoctoral Fellow. “First, we would not need ‘new physics’ to explain dark matter. Moreover, this would help us to answer one of the most compelling questions of modern astrophysics: How could supermassive black holes in the early universe have grown so big so fast? Given the mechanisms we observe today in the modern universe, they would not have had enough time to form. This would also solve the long-standing mystery of why the mass of a galaxy is always proportional to the mass of the supermassive black hole in its center.”

Dark matter, which has never been directly observed, is thought to be most of the matter in the universe and act as the scaffolding upon which galaxies form and develop. On the other hand, black holes, which can be found at the centers of most galaxies, have been observed. A point in space where matter is so tightly compacted, they create intense gravity.

Co-authored by Priyamvada Natarajan, professor of astronomy and physics at Yale, and Günther Hasinger, director of science at the European Space Agency (ESA), the new study suggests that so-called primordial black holes of all sizes account for all black matter in the universe.

How did supermassive black holes form? What is dark matter? In an alternative model for how the Universe came to be, as compared to the ‘textbook’ history of the Universe, a team of astronomers propose that both of these cosmic mysteries could be explained by so-called ‘primordial black holes’. In the graphic, the focus is on comparing the timing of the appearance of the first black holes and stars, and is not meant to imply there are no black holes considered in the standard model. Credit: ESA

“Black holes of different sizes are still a mystery,” Hasinger explained. “We don’t understand how supermassive black holes could have grown so huge in the relatively short time available since the universe existed.”

Their model tweaks the theory first proposed by Hawking and fellow physicist Bernard Carr, who argued that in the first fraction of a second after the Big Bang, tiny fluctuations in the density of the universe may have created an undulating landscape with “lumpy” regions that had extra mass. These lumpy areas would collapse into black holes.

That theory did not gain scientific traction, but Cappelluti, Natarajan, and Hasinger suggest it could be valid with some slight modifications. Their model shows that the first stars and galaxies would have formed around black holes in the early universe. They also propose that primordial black holes would have had the ability to grow into supermassive black holes by feasting on gas and stars in their vicinity, or by merging with other black holes.

“Primordial black holes, if they do exist, could well be the seeds from which all the supermassive black holes form, including the one at the center of the Milky Way,” Natarajan said. “What I find personally super exciting about this idea is how it elegantly unifies the two really challenging problems that I work on—that of probing the nature of dark matter and the formation and growth of black holes—and resolves them in one fell swoop.”

Primordial black holes also may resolve another cosmological puzzle: the excess of infrared radiation, synced with X-ray radiation, that has been detected from distant, dim sources scattered around the universe. The study authors said growing primordial black holes would present “exactly” the same radiation signature.

And, best of all, the existence of primordial black holes may be proven—or disproven—in the near future, courtesy of the Webb telescope scheduled to launch from French Guiana before the end of the year and the ESA-led Laser Interferometer Space Antenna (LISA) mission planned for the 2030s.

Developed by NASA, ESA, and the Canadian Space Agency to succeed the Hubble Space Telescope, the Webb can look back more than 13 billion years. If dark matter is comprised of primordial black holes, more stars and galaxies would have formed around them in the early universe, which is precisely what the cosmic time machine will be able to see.

“If the first stars and galaxies already formed in the so-called ‘dark ages,’ Webb should be able to see evidence of them,” Hasinger said.

LISA, meanwhile, will be able to pick up gravitational wave signals from early mergers of primordial black holes.

For more on this research, see Black Holes Could Be Dark Matter – And May Have Existed Since the Beginning of the Universe.

Reference: “Exploring the high-redshift PBH-ΛCDM Universe: early black hole seeding, the first stars and cosmic radiation backgrounds” by N. Cappelluti, G. Hasinger and P. Natarajan, Accepted, The Astrophysical Journal.
arXiv:2109.08701

Astronomers detect magnetic star flashing in an instant with the energy produced by the sun in 100,000 years

Astronomers have called it a "cosmic monster".

 by Tibi Puiu
January 3, 2022
in News, Space

Artist impression of the GRB 2001415 magnetar.

 Credit: Universitat de València.

Sure we might have enormous gas giants and menacing asteroids, but compared to other corners of the universe, our solar system is pretty vanilla. There are black holes whose mass exceeds billions of solar masses, generating a gravitational pull so intense that they shape the formation and evolution of entire galaxies. Then there are magnetars, much less famous than black holes but incredibly powerful in their own right. Case in point, astronomers in Spain have witnessed such an object erupt with as much energy as the sun produces in 100,000 years, concentrating it in just 0.1 seconds.

When truly massive stars die, they do so with a bang, triggering a supernova explosion. In the aftermath, some collapse under their own weight, forming into black holes. Those that don’t make the cut, often become neutron stars, second only to black holes in their stupendous density. A teaspoon of neutron star material would weigh around a billion tons, for instance.

There are multiple types of neutron stars, including magnetars. These objects have extremely powerful magnetic fields, a thousand trillion times stronger than the Earth’s, and between 100 and 1,000 times stronger than that of a radio pulsar. They’re essentially the most powerful magnets in the universe.

Magnetars are quite rare, with only a couple dozen such objects having been identified so far. One of them, located in the Sculptor Galaxy about 13 million light-years away, was under observation by astronomers using the Atmosphere-Space Interactions Monitor (ASIM) aboard the International Space Station when a giant flare was detected.

The flare, known as the GRB 2001415 event, released roughly the energy the sun radiates in about 100,000 years in just two short quasi-periodic pulsations that lasted approximately 160 milliseconds.

“Even in an inactive state, magnetars can be one hundred thousand times more luminous than our Sun, but in the case of GRB 2001415, the energy that was released is equivalent to that which our Sun radiates in 100,000 years,” said Dr. Alberto Castro-Tirado, an astrophysicist with the Instituto de Astrofísica de Andalucía del Consejo Superior de Investigaciones Científicas (IAA-CSIC) and the Universidad de Málaga. “It’s a true cosmic monster,” added Professor Víctor Reglero, an astrophysicist at the Universitat de València and co-author of the new study.

The magnetar explosion was detected on April 15, 2020 thanks to an artificial intelligence system integrated with ASIM. If this kind of system wasn’t in place, the astronomers would have been oblivious to the event, whose signal decayed into background noise within a fraction of a second.

No one’s really sure what triggered the eruption, but the researchers believe it could have been due to instabilities in the magnetosphere or ‘earthquakes’ produced in their crust. Further research could help scientists reveal the mechanisms that trigger these frightening but, at the same time, fascinating cosmic burps.

“Although these eruptions had already been detected in two of the thirty known magnetars in our Galaxy and in some other nearby galaxies, GRB 2001415 would be the most distant magnetar eruption captured to date, being in the Sculptor group of galaxies about 11 million light-years,” said Professor Reglero.

“Seen in perspective, it has been as if the magnetar wanted to indicate its existence to us from its cosmic solitude, singing in the kHz with the force of a Pavarotti of a billion suns.”

The findings appeared in the journal Nature.


Tibi Puiu is a science journalist and co-founder of ZME Science. He writes mainly about emerging tech, physics, climate, and space. In his spare time, Tibi likes to make weird music on his computer and groom felines.