Category: 7. Science

  • The Chang’e-6 “illuminates” the dark side of the moon, thanks to the samples collected

    The Chang’e-6 “illuminates” the dark side of the moon, thanks to the samples collected

    The Chinese Mission Chang’e-6 has returned to Earth with over 1.9 kg of samples with a hidden face of the moon: this is what this “scientific treasure” tells.

    The Chinese Mission Chang’e-6 returned to Earth in June 2024 with over 1.9 kg of samples from the hidden face of the moon. Thanks to this scientific treasure, the Guangzhou Institute of Geochemistry (CAS) group has established the age of the Apollo basin, where Chang’e-6 landed: about 4.16 billion years ago, anticipating the beginning of the so-called Late Heavy Bombardment (LHB) of at least 100 million years compared to previous estimates.

    The Late Heavy Bombardment was a period in which the Earth, the Moon and the other rocky planets of the Solar System were affected by an exceptionally high number of asteroids and comets. It seems that it has lasted about 100 million years.

    Without sudden peaks. The new study published on Nature Astronomy It reveals that the impact flow during the LHB was not a sudden tsunami between 3.8 and 4 billion years ago, but a slow influx of material over time, dismantling the hypothesis of a sudden peak.

    Previously, another study had already dated the gigantic South Pole – Aitken (Spa) Basin – inside which the Apollo basin is located – at about 4.25 billion years ago, based on the Champs of Chang’e -6 and published on National Science Review.

    A magma ocean. This discovery follows various other discoveries to bring from the moon champions of the Chinese probe. Among these, a surprising result comes from a study published on Science: thanks to isotopic analysis of the champions, it is confirmed that the moon, in its very first moments, was covered entirely by an magma ocean.

    This suggests that the model of the “Crustal Flotation” and the formation of the lunar crust, so far based only on the champions of the nearby side, is also valid for the hidden side.

    Volcani at the poles. Another discovery of great interest comes from the basalts collected: some of these have an age of about 2.8 billion years, a sign that the hidden face of the moon has known volcanic activity much more recent than what was thought.

    Others, on the other hand, are 4.2 billion years older and thus tell a long and complex fusion and cooling story.

    Stratified land. But that’s not all, because a geological study of the landing area then published on Journal of Geophysical Research: Planetsreveals a fluid story: the mission has collected materials linked to three distinct phases of volcanism (EMSAP1, EMSAP2, and EMSAP3), separated from intervals of about one billion years. The unit on which Chang’e-6 (EMSAP2) landed dates back to 2.81 ga, while 30 % of the regolite comes from external craters, transported to the place by impact material of large asteroids.

    The face hidden. For decades, we have had clues to the history of the moon only from material from the face addressed to us and this thanks to the samples brought to the ground by the Apollo mission and the Russian missions called “Luna”.

    Now, thanks to Chang’e-6, we finally know that there were oceans of magma everywhere, that the hidden face has had active volcanoes up to much more recent periods and that the isotopic and geochimic structure differs-industry parallel but different evolutions in the two hemispheres.

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  • Amycolatopsis cyclosori sp. nov., isolated from the rhizosphere soil of Cyclosorus parasiticus

    Amycolatopsis cyclosori sp. nov., isolated from the rhizosphere soil of Cyclosorus parasiticus

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  • Characterization of toxin systems of Paenibacillus strains isolated from honeybees

    Characterization of toxin systems of Paenibacillus strains isolated from honeybees

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  • Rare milky plumes paint stunning swirls in world’s largest ‘soda lake’ — Earth from space

    Rare milky plumes paint stunning swirls in world’s largest ‘soda lake’ — Earth from space

    QUICK FACTS

    Where is it? Lake Van, Turkey [38.91395038, 43.12483070]

    What’s in the photo? Rare plumes of mostly inorganic matter swirling in an alkaline lake

    Who took the photo? NASA astronaut Kate Rubins, on board the International Space Station

    When was it taken? Sept. 12, 2016

    This stunning astronaut photo shows a series of milky swirls that appeared in the waters of Turkey’s Lake Van, the largest “soda lake” on Earth. While the swirls look like a common natural phenomenon, they’re actually something much rarer.

    Lake Van is the largest lake in Turkey with a surface area of around 1,200 square miles (3,100 square kilometers), which is slightly smaller than Rhode Island. Its surface is located at an altitude of 5,380 feet (1,640 meters) above sea level and has a pH of around 10, which is highly alkaline.

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  • Final Call For Six-Planet ‘Parade’ On Wednesday — When To See It

    Final Call For Six-Planet ‘Parade’ On Wednesday — When To See It

    Topline

    Six planets line up in the pre-dawn sky on Wednesday, Aug. 27 — but not for long. Venus, Jupiter, and Saturn will shine brilliantly, joined by fainter Mercury rising shortly before the sun. Uranus and Neptune are also in the parade, though only binoculars or a telescope will reveal them. With Mercury slipping into the sun’s glare, this rare six-planet spectacle will soon give way to a five-planet show.

    Key Facts

    Best seen at least an hour before sunrise, the most easily found members of the alignment will be Venus and Jupiter in the eastern sky. They will be about 15 degrees apart.

    Saturn shines in the southwest, higher than Mercury but fainter than Venus and Jupiter. The moon is not in the sky at all during the parade this week.

    Mercury, the smallest and hardest to find of the group, will appear just above the horizon about 45 minutes before sunrise. Find an unobstructed view toward the east for the best chance of spotting it.

    Mercury is not easy to see because it appears below about 10 degrees altitude, according to NASA. It will remain easily visible until around Aug. 26, after which it will sink into the eastern horizon. Seeing the outer ice giants Uranus and Neptune requires binoculars or a telescope.

    Planet-rise and planet-set times for an exact location vary, so use an online planetarium that displays that data. The following planet parade will occur in October 2028, when five planets will be visible together, again before sunrise.

    Finding The ‘winter Triangle’

    Look to the right of Jupiter and Venus and you’ll see the bright stars that make up a triangle — Betelgeuse in Orion at the top, a little higher than Jupiter, and, below it, Procyon in Canis Major (left, close to Venus) and Sirius in Canis Major (right). Its name comes from the fact that it’s typically visible from November in the post-sunset night sky. However, since we’re four months away from that, it resides in the pre-sunrise night sky.

    What’s Next In The Night Sky

    The fading planet parade will give way to September’s mix of eclipses, conjunctions and planetary drama. Three bright planets — Saturn, Jupiter and Venus — will be left to anchor the evening skies after Mercury disappears into sunlight in late-August. September’s headline event arguably comes on Sept. 7 with a “blood moon” total lunar eclipse, though that’s only visible from Asia and Africa. On Sept. 19, Venus will be visible before sunrise very close to both a super-slim crescent moon and Regulus, the brightest star in the constellation Leo. On Sept. 21, a partial solar eclipse occurs over the Pacific on the same day that Saturn reaches opposition, shining at its biggest, brightest and best for all of 2025.

    Further Reading

    Forbes‘Planet Parade’ Myths Debunked And How To Truly See It — By A StargazerBy Jamie CarterForbesNASA Urges Public To Leave The City As Milky Way Appears — 15 Places To GoBy Jamie CarterForbes9 Places To Experience The Next Total Solar Eclipse A Year From TodayBy Jamie Carter

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  • New SpaceX Mission Will Launch 3D Printed Liver Tissue to the ISS

    New SpaceX Mission Will Launch 3D Printed Liver Tissue to the ISS

    Researchers from Wake Forest Institute for Regenerative Medicine (WFIRM) will soon launch 3D printed liver tissue to the International Space Station (ISS) aboard SpaceX’s Falcon 9 rocket.  

    The project, sponsored by the ISS National Laboratory, will investigate how microgravity environments impact the behavior of functional artificial organ constructs. This could provide new insights into how scientists can manufacture longer-lasting cellular structures for researching diseases and treating patients on Earth.  

    Two research teams from the institute, Team Winston and Team WFIRM, utilized 3D bioprinting technology to create live organ tissue samples, complete with complex vascular channels, as part of NASA’s Vascular Tissue Challenge. This competition seeks to accelerate tissue engineering and advance regenerative medicine technologies.  

    They received $400,000 in funding as a result of their earlier earth-bound demonstrations, where their 3D printed tissues functioned in laboratories for up to 30 days. In space, however, zero gravity alters cell distribution, behaviour, and adhesion in vascularised constructs. These changes could hold the key to improving the viability of artificial organs.

    Team Winston will be the first of the two to dispatch its samples to the ISS. Once in orbit, the 3D printed tissues will be assessed using Redwire Space’s Multi-Use Variable-Gravity Platform (MVP).  

    The project is slated to launch aboard SpaceX’s 33rd Commercial Resupply Services mission, scheduled to lift off from Cape Canaveral Space Force Station no earlier than August 24th, 2025, at 2:45 a.m. Eastern time. The NASA-contracted flight will ferry more than 20 experimental payloads, sponsored by the ISS National Lab, on SpaceX’s Falcon 9 rocket.

    “This collaborative investigation has the potential to yield remarkable results,” explained James Yoo, the WFIRM professor leading the work. “By leveraging bioprinting technologies, we’ve created gel-like frameworks with channels for oxygen and nutrient flow that mimic natural blood vessels, opening up new possibilities for medical treatments both on Earth and in space.” 

    SpaceX's Falcon 9 Rocket, which will carry ISS National Lab-sponsored research to the International Space Station. Photo via NASA.
    SpaceX’s Falcon 9 Rocket, which will carry ISS National Lab-sponsored research to the International Space Station. Photo via NASA.

    Testing 3D Printed organ tissue in space  

    During 3D bioprinting, scientists load living human cells into bioinks and extrude them to create functional replicas of organ tissues. These can be used to study illnesses, test medications, and repair tissues damaged by injury, ageing, or pathological conditions.

    WFIRM’s two research teams at WFIRM used this method to fabricate liver tissue with vascular channels. On Earth, producing thick bioprinted tissue remains difficult because stable vascularisation is hard to achieve. Current 3D printed tissues struggle to take in oxygen and nutrients while removing metabolic waste. As a result, engineered tissue degrades quickly, with WFIRM’s 3D printed liver lasting only 30 days.

    Microgravity may offer a solution to these hurdles. Without Earth’s gravitational force, cells change how they distribute, behave, and adhere. Understanding these shifts, researchers argue, could yield insights into making longer-lasting functional tissue. 

    WFIRM’s ISS experiments will study how microgravity influences cell behaviour, with the goal of improving tissue growth and maturation. The team will test whether vascular cells can properly line the blood vessels in a liver construct. Yoo believes the results could advance tissue engineering on Earth and, in time, make space-printed constructs viable for transplants.

    NASA’s Vascular Tissue Challenge is part of the agency’s Centennial Challenges program under the Space Technology Mission Directorate. The Methuselah Foundation’s New Organ Alliance organized the competition and convened a panel of nine judges specializing in regenerative medicine. The effort is supported by experts from NASA, the National Institutes of Health, the ISS National Lab, and leading universities.

    “Our mission at the Methuselah Foundation involves advancing human longevity through regenerative medicine,” explained the Methuselah Foundation’s co-founder and CEO, David Gobel. “By collaborating with NASA and the ISS National Lab to accelerate innovation, we’re not only improving human health on Earth but also preparing for the challenges of space exploration and bolstering the future space industry.”

    3D bioprinted tissue construct used to replicate human tissue. Photo via Wake Forest Institute for Regenerative Medicine.

    Additive manufacturing on the ISS

    The ISS is a key hub for on-orbit 3D printing research. Over recent years, additive manufacturing companies, academic researchers, and commercial enterprises have sent 3D printing technologies for testing in microgravity conditions. 

    A recent review by researchers from Xi’an Jiaotong University and the China Academy of Space Technology offers a comprehensive account of in-space 3D printing using polymers and fiber-reinforced composites. The document, published on ScienceDirect, identified additive manufacturing as a transformative approach to fabricating space structures. 

    3D printing components on-orbit addresses challenges associated with payload mass, onboard spares, and launch geometry. Launching earth-made items into space can cost over $10,000 per kilogram. 

    The review identified FFF as the most viable microgravity technique due to its use of solid filament feedstock and absence of free-flowing liquids or powders. NASA first tested microgravity extrusion with ABS during a parabolic flight in 1999. Further campaigns by Made In Space Inc. (MIS) placed the first 3D printer aboard the ISS in 2014.

    More recently, Finnish bioprinting firm Brinter AM Technologies announced plans in 2024 to launch its Brinter Core 3D bioprinter to the ISS in a European Space Agency-funded mission. Once aboard, the Brinter Core will be used to 3D print biosamples in the ISS Columbus module’s 3D BioSystem facility. 

    ISS personnel will use the system to study how microgravity affects 3D printed cell constructs. The work aims to improve responses to medical emergencies in space and to advance personalized drug testing, toxicology studies, and the bioprinting of body parts. Tomi Kalpio, CEO of Brinter, noted that, in the future, astronauts could use bioprinters to “create tissue-like constructs to replace damaged parts of their bodies” when treating skin burns or bone damage. 

    Registrations are now open for Additive Manufacturing Advantage: Energy on September 17th. Reserve your free ticket now.

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    Featured image shows SpaceX’s Falcon 9 Rocket, which will carry ISS National Lab-sponsored research to the International Space Station. Photo via NASA.

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  • What first images from Vera Rubin telescope mean for space research

    What first images from Vera Rubin telescope mean for space research

    Prof Manda Banerji and Dr Phil Wiseman from the University of Southampton argue that the cosmic power of this telescope will expand our understanding of the universe beyond our wildest dreams.

    We are entering a new era of cosmic exploration. The new Vera C Rubin Observatory in Chile will transform astronomy with its extraordinary ability to map the universe in breathtaking detail. It is set to reveal secrets previously beyond our grasp.

    Here, we delve into the first images taken by Rubin’s telescope and what they are already showing us.

    These images vividly showcase the unprecedented power that Rubin will use to revolutionise astronomy and our understanding of the universe. Rubin is truly transformative, thanks to its unique combination of sensitivity, vast sky area coverage and exceptional image quality.

    These pictures powerfully demonstrate those attributes. They reveal not only bright objects in exquisite detail but also faint structures, both near and far, across a large area of sky.

    Cosmic nurseries

    The stunning pink and blue clouds in this image are the Lagoon (lower left) and Trifid (upper right) nebulae. The word nebula comes from the Latin for cloud, and these giant clouds are truly enormous – so vast it takes light decades to travel across them. They are stellar nurseries, the very birth sites for the next generation of stars and planets in our Milky Way galaxy.

    The intense radiation from hot, young stars energises the gas particles, causing them to glow pink. Further from these nascent stars, colder regions consist of microscopic dust grains. These reflect starlight (a process known in astronomy as ‘scattering’), much like our atmosphere, creating the beautiful blue hues. Darker filaments within are much denser regions of dust, obscuring all but the brightest background stars.

    To detect these colours, astronomers use filters over their instruments, allowing only certain wavelengths of light onto the detectors. Rubin has six such filters, spanning from short ultraviolet (UV) wavelengths through the visible spectrum to longer near-infrared light. Combining information from these different filters enables detailed measurements of the properties of stars and gas, such as their temperature and size.

    Rubin’s speed – its ability to take an image with one filter and then quickly move to the next – combined with the sheer area of sky it can see at any one time, is what makes it so unique and so exciting. The level of detail, revealing the finest and faintest structures, will enable it to map the substructure and satellite galaxies of the Milky Way like never before.

    Mapping galaxies across billions of light years

    The images of galaxies powerfully demonstrate the scale at which the Rubin observatory will map the universe beyond our own Milky Way. The large galaxies visible here (such as the two bright spiral shaped galaxies visible in the lower right quarter of the picture) belong to the Virgo cluster, a giant structure containing more than 1,000 galaxies, each holding billions to trillions of stars.

    A small section of NSF–DOE Vera C. Rubin Observatory’s view of the Virgo Cluster, offering a vivid glimpse of the variety in the cosmos. Image: NSF–DOE Vera C Rubin Observatory

    This image beautifully showcases the huge diversity of shapes, sizes and colours of galaxies in our universe revealed by Rubin in their full technicolour glory. Inside these galaxies, bright dots are visible – these are star-forming regions, just like the Lagoon and Trifid nebulae, but remarkably, these are millions of light years away from us.

    The still image captures just 2pc of the area of a full Rubin image revealing a universe that is teeming with celestial bodies. The full image, which contains around ten million galaxies, would need several hundred ultra-high-definition TV screens to display in all its detail.

    By the end of its ten-year survey, Rubin will catalogue the properties of some 20bn galaxies, their colours and locations on the sky containing information about even more mysterious components of our universe such as dark matter and dark energy.

    Dark matter makes up most of the matter in the cosmos but does not reflect or emit light. Dark energy seems to be responsible for the accelerating expansion of the universe.

    Handling all that data

    These unfathomable numbers demand data processing on a whole new scale. Uncovering new discoveries from this data requires a giant collaborative effort, in which UK astronomy is playing a major role.

    The UK will process around 1.5m Rubin images and hosts one of three international data access centres for the project, providing scientists across the globe with access to the vast Rubin data. Here at the University of Southampton, we are leading two critical software development contributions to Rubin.

    The first of these is the capability to combine the Rubin images with those at longer infrared wavelengths. This extends the colours that Rubin sees, providing key diagnostic information about the properties of stars and galaxies. Second is the software that will link Rubin observations to another new instrument called 4MOST, soon to be installed at the Vista telescope in Chile.

    Part of 4MOST’s job will be to snap up and classify rapidly changing ‘sources’, or objects, in the sky that have been discovered by Rubin.

    One such type of rapidly changing source is a stellar explosion known as a supernova. We expect to have catalogued more supernova explosions within just two years than have ever been made previously. Our contributions to the Rubin project will therefore lead to a totally new understanding of how the stars and galaxies in our universe live and die, offering an unprecedented glimpse into the grand cosmic cycle.

    The Rubin observatory isn’t just a new telescope – it’s a new pair of eyes on the universe, revealing the cosmos in unprecedented detail. A treasure trove of discoveries await, but most interesting among them will be the hidden secrets of the universe that we are yet to contemplate.

    The first images from Rubin have been a spectacular demonstration of the vastness of the universe. What might we find in this gargantuan dataset of the cosmos as the ultimate timelapse movie of our universe unfolds?

    The Conversation
    By Prof Manda Banerji and Dr Phil Wiseman

    Prof Manda Banerji is professor of astrophysics in the Astronomy Group and associate dean for equality, diversity and inclusion in the Faculty of Engineering and Physical Sciences at the University of Southampton.

    Dr Phil Wiseman is Ernest Rutherford fellow at the University of Southampton. He researches the most extreme events in the universe: exploding stars (supernovae) and giant flares from super-massive black holes.

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  • precision molecules for tomorrow’s electronics

    precision molecules for tomorrow’s electronics

    Empa researchers have succeeded for the first time in binding organic porphyrin molecules with functional metal centers to a graphene nanoribbon with atomic precision. The resulting hybrid system is magnetically and electronically coupled, paving the way for a wide range of applications in molecular electronics, from chemical sensing to quantum technologies.

    A graphene nanoribbon connects porphyrin molecules – each featuring a metal center (red) – like a molecular string of Christmas lights. The metal atoms are held in place by four nitrogen atoms (blue) within the porphyrin core

    Empa

    Empa

    Ultimate precision: With their method, Empa researchers can synthesize the molecular structure with atomic precision, as confirmed by microscopy imaging (top: scanning tunneling microscopy; bottom: non-contact atomic force microscopy).

    Empa

    Empa
    Empa

    Organic chemistry, the chemistry of carbon compounds, is the basis of all life on Earth. However, metals also play a key role in many biochemical processes. When it comes to “marrying” large, heavy metal atoms with light organic compounds, nature often relies on a specific group of chemical structures: porphyrins. These molecules form an organic ring; in its center, individual metal ions such as iron, cobalt, or magnesium can be “anchored”.

    The porphyrin framework forms the basis for hemoglobin in human blood, photosynthetic chlorophyll in plants, and numerous enzymes. Depending on which metal is captured by the porphyrin, the resulting compounds can display a wide range of chemical and physical properties. Chemists and materials scientists have long sought to exploit this flexibility and functionality of porphyrins, including for applications in molecular electronics.

    However, for electronic components – even molecular ones – to function, they must be connected to each other. Wiring up individual molecules is no easy task. But this is precisely what researchers at Empa’s nanotech@surfaces laboratory have achieved, in collaboration with synthetic chemists from the Max Planck Institute for Polymer Research. They have succeeded in attaching porphyrins to a graphene nanoribbon in a perfectly precise and well-defined manner. The corresponding study has just been published in the journal Nature Chemistry.

    A carbon “backbone”

    Graphene nanoribbons are long, narrow strips of the two-dimensional carbon material graphene. Depending on their width and the shape of their edges, they exhibit a wide range of physical properties, including different conductivities, magnetism, and quantum behavior. The Empa researchers used a ribbon just one nanometer wide with so-called zigzag edges as a molecular wire. Along these edges, the porphyrin molecules are docked at perfectly regular intervals, alternating between the ribbon’s left and right sides.

    “Our graphene ribbon exhibits a special type of magnetism thanks to its zigzag edge,” explains Feifei Xiang, lead author of the study. The metal atoms in the porphyrin molecules, on the other hand, are magnetic in a more “conventional” way. The difference lies in the electrons that provide the spin responsible for magnetism. While the spin-carrying electrons in the metal center stay localized on the metal atom, the corresponding electrons in the graphene ribbon “spread out” along both edges. “Thanks to the coupling of the porphyrins to the graphene backbone, we have succeeded in combining and connecting both types of magnetism in a single system,” explains co-author Oliver Gröning, deputy head of the nanotech@surfaces laboratory.

    This coupling opens many doors in the field of molecular electronics. The graphene ribbon serves as both an electrical and magnetic conductor – a kind of nanoscale “cable” between the porphyrin molecules. The correlated magnetism of such graphene nanoribbons is considered particularly promising for quantum technology applications, where the spin underlying magnetism acts as an information carrier. “Our graphene ribbon with the porphyrins could function as a series of interconnected qubits,” says Roman Fasel, head of the “nanotech@surfaces” laboratory.

    But that’s not all: Porphyrins are also natural pigments, as seen in molecules like chlorophyll and hemoglobin. For materials scientists, this means that “the porphyrin centers are optically active,” says Gröning. And optics is an important way of interacting with the electronic and magnetic properties of such molecular chains. Porphyrins can emit light whose wavelength changes with the magnetic state of the entire molecular system – a kind of molecular string of lights, where information could be read out by subtle shifts in color.

    The reverse process is also possible: The porphyrins could be excited by light, thereby influencing the conductivity and magnetism of the graphene backbone. These molecular all-rounders could even serve as chemical sensors. Porphyrin molecules can be easily functionalized – that is, chemically modified by attaching specific chemical groups. If one of these added groups binds to a target chemical substance, this interaction also affects the conductivity of the graphene ribbon.

    “Our system is a toolbox that can be used to tune different properties,” says Fasel. Next, the researchers plan to explore different metal centers inside the porphyrins and investigate their effects. They also aim to broaden the graphene ribbon backbone, giving their molecular system an even more versatile electronic base. The synthesis of these “string lights” is anything but trivial. “Our partners at the Max Planck Institute were able to produce precursor molecules consisting of a porphyrin core complemented by a few carbon rings placed at exactly the right positions,” says Gröning. These complex molecules are then “baked” at several hundred degrees Celsius under ultra-high vacuum to form the long chains. A gold surface serves as the “baking sheet”. This is the only way to achieve these nanometer-fine structures with atomic precision. With support from the Werner Siemens Foundation, the Empa team is now working to make these novel designer materials usable for future quantum technologies.

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  • Rare Space Dust Reveals a Shocking Link Between Very Different Asteroids

    Rare Space Dust Reveals a Shocking Link Between Very Different Asteroids

    Two very different asteroid families may share the same ancient roots, linked by a rare mineral fingerprint and revealed through cutting-edge polarization studies. (Artist’s concept.) Credit: SciTechDaily.com

    Scientists studying asteroids found that two seemingly unrelated types share a strange dusty coating of troilite.

    By using polarization of light instead of traditional spectra, Joe Masiero uncovered evidence that these space rocks may have originated from the same ancient parent bodies, offering a new glimpse into the chaotic past of the early solar system.

    Ancient Solar System Origins

    Around 4.6 billion years ago, the solar system took shape out of a vast swirl of gas and dust surrounding the Sun. The asteroids that remain today are among the most complete relics from that chaotic era, comparable to scraps and spare parts left behind at a construction site. By analyzing their shapes, surfaces, and chemical makeup, scientists can uncover clues about what conditions were like when the solar system first formed.

    To better understand these rocky remnants, researchers sort asteroids into groups based on shared traits. A new study in The Planetary Science Journal, led by IPAC scientist Joe Masiero, presents evidence that two very different types of asteroids may have endured the same turbulent history.

    “Asteroids offer us the chance to look at what was going on in the early solar system like a freeze frame of the conditions that existed when the first solid objects formed,” said Masiero.

    Asteroid Phases Mosaic
    This image shows how an asteroid would appear during different phases depending on its location relative to the Sun, similar to how the Moon has phases. Credit: Caltech/IPAC/K. Miller

    A Rare Fingerprint in Space Rocks

    Drawing on data from Caltech’s Palomar Observatory, Masiero and his team examined two asteroid types: one dominated by metal and another composed largely of silicates and other minerals. Despite their contrasting makeups, both were found to carry the same unusual dusty coating made of iron and sulfur, a substance known as troilite.

    “Troilite is very uncommon, so we can use it as a fingerprint that links these two different types of objects to each other,” said Masiero.

    This animation shows how an asteroid would appear during different phases depending on its location relative to the Sun, similar to how the Moon has phases. Credit: Caltech/IPAC/K. Miller

    Asteroid Spectra and Classifications

    Asteroids are separated into different classes based on the spectrum of light reflected off of their surface, denoted by letters such as M, K, C, and more. The spectra can show the presence of carbon, silicates, or metals in the regolith, or surface dirt, of the asteroid.

    In this study, Masiero looked at M- and K-type asteroids. M-types are metal-rich, while K-types are composed of silicates and other materials and thought to be linked to an ancient giant collision between asteroids. About 95 percent of Earth’s crust and mantle are made up of silicates.

    But the same materials on asteroids can appear differently depending on the shape of the asteroid, the size of the regolith (dust, pebbles, boulders), and the phase angle of the asteroid relative to the Sun.

    Asteroids in our solar system are constantly moving: orbiting the Sun and rotating on their own axis, and because of this, just like how the Moon has phases, asteroids do too. The phase angle is the angle between the Sun, asteroid, and the Earth.

    “While spectra indicate that there are different minerals on the surface of these objects, we’re trying to figure out how different these bodies truly are,” said Masiero. “We want to wind the clock back to when these formed and what conditions they formed under in the early solar system.”

    Probing Asteroids with Polarization

    Masiero turned to polarization, particularly in the near-infrared, as a method for studying asteroids. By measuring the polarization of the reflected light on the M- and K-type asteroids he was studying, Masiero shows that the two previously discrete asteroid spectral classes may actually be linked through their surface composition.

    Polarization describes the direction of the waves that make up light, similar to how brightness is a measurement of how many photons there are, or how color is a measurement of the wavelength. Different surface minerals have different polarization responses when they reflect light, the same way they can have different colors.

    Changes in an asteroid’s phase angle can significantly affect polarization, and this response is a result of the variety of materials on the surface. Masiero used the way the degree of polarization changes with phase angle to investigate the makeup of the asteroids’ surfaces. This technique can probe the composition even when the minerals don’t show any color or spectral response.

    “Polarization gives us insight into the minerals in the asteroids that we can’t get from just how well the asteroid reflects sunlight, or what the reflected light’s spectrum looks like,” said Masiero. “Polarization gives you a third axis to ask questions about the surface mineralogy that’s independent of brightness or spectral information.”

    Unlocking Secrets at Palomar

    Masiero used the WIRC+Pol instrument at Caltech’s Palomar Observatory in the mountains above San Diego, California.

    “Palomar is such a fabulous facility. It’s great to interact with the observing team there; the telescope operators and the support astronomers really are helpful in making sure you can get the best data possible,” said Masiero. “For the infrared polarization data I needed, there is no other instrument that can get nearly as deep. This is an asset unique to Palomar.”

    Tracing a Shared Ancestry

    After the polarization studies, Masiero concludes that both M- and K-type asteroids share the same dusty surface of troilite, an iron sulfide material.

    Masiero argues that the evidence of troilite is a sign that these two types of asteroids actually came from similar types of original, larger objects that later broke apart to create the asteroids we see today.

    The different overall compositions of the asteroids can be linked to the different layers within the large original objects. Like how Earth has a core, mantle, and crust made of different materials, these types of asteroids could originate from the different layers.

    The troilite dust may have been abundant on an original object before breaking up, or it could have been a cloud of dust that covered everything after it broke up, but its roots are still unknown.

    “You can’t go and rip the Earth open to see what is inside, but you can look at asteroids—the leftover bits and pieces, the unused components from solar system formation—and use them to see how our planets were built,” said Masiero.

    Reference: “The Mineralogical Connection between M- and K-type Asteroids as Indicated by Polarimetry” by Joseph R. Masiero, Yuna G. Kwon, Elena Selmi and Manaswi Kondapally, 20 August 2025, The Planetary Science Journal.
    DOI: 10.3847/PSJ/ade433

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  • Scientists Think This Star Could Be the Next Supernova

    Scientists Think This Star Could Be the Next Supernova

    Red supergiant DFK 52 and its surroundings as seen by ALMA. The vast, complex bubble blown by this extreme star is about 1.4 light-years across, thousands of times wider than our Solar System. ALMA measures light invisible to the human eye, with a wavelength of around 1.3 millimeters, emitted by molecules of carbon monoxide and silicon monoxide. Thanks to the Doppler effect, the team has measured how fast the gas is moving along our sightline towards the star. In this image, parts of the bubble moving away from us relative to the star are shown in red, and material moving towards us in blue. Credit: ALMA (ESO/NAOJ/NRAO)/M. Siebert et al.

    A red supergiant star has blown an enormous bubble of gas and dust, baffling astronomers.

    The structure, as massive as the Sun and larger than our solar system, formed in a sudden eruption thousands of years ago. Why the star didn’t explode as a supernova remains a mystery.

    Discovery of a Vast Stellar Bubble

    Astronomers at Chalmers University of Technology in Sweden have identified a gigantic, expanding bubble of gas and dust surrounding a red supergiant star. It is the largest structure of this kind ever observed in the Milky Way. Containing as much mass as the Sun, the bubble was expelled in a violent stellar eruption about 4000 years ago. Scientists are still puzzled as to how the star managed to survive such a dramatic event.

    The findings, published in the journal Astronomy and Astrophysics, come from a team led by Mark Siebert of Chalmers. Using the ALMA radio telescope in Chile, the researchers studied the red supergiant known as DFK 52, a star similar in many ways to the famous Betelgeuse.

    Red Supergiant Star DFK 52
    Red supergiant star DFK 52 is a member of the star cluster Stephenson 2. In this image, the brightest stars are all supergiants and all members of the cluster. This image is made from data taken with the Spitzer Space Telescope in light much redder than our eyes can see (wavelengths 3.6, 4.5, 5.8, and 8 micrometers). Despite its remarkable bubble, too small to see in this image, DFK 52 is not unusually bright. The bright star in the lower left is another red supergiant, known as DFK 1 or Stephenson 2-18. It may be one of the largest stars known. Credit: NASA/JPL-Caltech/IPAC

    A Giant, Expanding Cloud of Gas and Dust

    “We got a big surprise when we saw what ALMA was showing us. The star is more or less a twin of Betelgeuse, but it’s surrounded by a vast, messy bubble of material,” says Mark Siebert at Chalmers.

    This immense cloud, made of gas and dust, holds as much mass as the Sun and stretches 1.4 light years from the star. To put that in perspective, the bubble is thousands of times wider than our entire solar system.

    If DFK 52 were as close to Earth as Betelgeuse, the bubble would appear to cover about one third of the full Moon’s width in the night sky.

    Mark Siebert
    Mark Siebert, astronomer, Department of Space, Earth and Environment, Chalmers University of Technology, Sweden. Credit: Chalmers University of Technology | Christian Löwhagen

    By tracking the movement of molecules in the gas with ALMA’s radio observations, astronomers determined that the bubble is still expanding. They believe it originated when the star violently ejected part of its outer layers during an explosive outburst a few thousand years ago.

    “The bubble is made of material that used to be part of the star. It must have been ejected in a dramatic event, an explosion, that happened about four thousand years ago. In cosmic terms, that’s just a moment ago,” says Elvire De Beck, astronomer at Chalmers.

    The Galaxy’s Next Supernova?

    Why DFK 52 shed so much mass without exploding as a supernova is still unclear. One possibility is that the star has a hidden companion that helped it cast off its outer layers.

    “To us, it’s a mystery as to how the star managed to expel so much material in such a short timeframe. Maybe, like Betelgeuse seems to, it has a companion star that’s still to be discovered,” says Mark Siebert.

    Elvire De Beck
    Elvire De Beck, astronomer, Department of Space, Earth and Environment, Chalmers University of Technology, Sweden. Credit: Chalmers University of Technology | Christian Löwhagen

    Red supergiants like DFK 52 are nearing the ends of their lives and are expected to eventually explode as supernovae. Could this star be next?

    “We’re planning more observations to understand what’s happening – and to find out whether this might be the Milky Way’s next supernova. If this is a typical red supergiant, it could explode sometime in the next million years,” says Elvire De Beck.

    Reference: “Stephenson 2 DFK 52: Discovery of an exotic red supergiant in the massive stellar cluster RSGC2” by M. A. Siebert, E. De Beck, G. Quintana-Lacaci and W. H. T. Vlemmings, 6 August 2025, Astronomy & Astrophysics.
    DOI: 10.1051/0004-6361/202555975

    The study was carried out by Mark Siebert, Elvire De Beck, and Wouter Vlemmings from Chalmers University of Technology in Sweden, together with Guillermo Quintana Lacaci from the Instituto de Fisica Fundamental in Spain.

    Red supergiants are among the brightest and rarest stars visible in the universe. They represent the final stage in the lives of stars that began with far greater mass than our Sun (more than eight times its mass). For astronomers, these stars are crucial for piecing together the life cycles of stars and planets. The most massive ones produce and release newly created elements into interstellar space, stirring up gas and dust and fueling the formation of future generations of stars.

    Within our own galaxy, the Milky Way, some red supergiants are visible without a telescope to anyone under a dark sky. Two of the best-known examples are Betelgeuse in the constellation Orion and Antares in Scorpius.

    ALMA Antennas Pointing to the Milky Way on Atacama Desert
    ALMA antennas pointing to the Milky Way in the Atacama Desert. Credit: NSF/ AUI/ NSF NRAO/ B.Foott

    The Atacama Large Millimeter/submillimeter Array (ALMA) is a world-class observatory located in Chile. It is operated as a collaboration between ESO, the U.S. National Science Foundation (NSF), and Japan’s National Institutes of Natural Sciences (NINS), working together with the Republic of Chile.

    In Sweden, Onsala Space Observatory at Chalmers University of Technology has played a role in ALMA from the very beginning. Among its contributions are specialized receivers built for the telescope. Onsala also hosts the Nordic ALMA Regional Centre, which offers technical expertise for the project and helps astronomers across the Nordic countries make full use of ALMA’s capabilities.

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