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Saturn’s moon Titan is perhaps one of the most fascinating moons in the Solar System. It’s the second largest of all the moons in our planetary neighbourhood and is the only one with a significant atmosphere. It’s composed of 95% nitrogen and 5% methane and is 1.5 times as dense as the Earth’s atmosphere. The methane in the atmosphere of Titan is what puzzles scientists. It should have all be broken up within 30 million years causing the atmosphere to freeze but it hasn’t! There must be an internal process replenishing it, but what is it?

Titan is the largest moon of Saturn and second only in size to Ganymede, the largest moon of Jupiter. The surface of Titan is covered with dunes, icy mountains, and liquid hydrocarbon lakes—primarily composed of methane and ethane. Beneath its icy crust, scientists believe a vast subsurface ocean of water exists, raising the possibility of microbial life. NASA’s Cassini-Huygens mission provided detailed insights into Titan’s climate, seasonal changes, and its resemblance to early Earth, making it a target for future exploration.

Natural color image of Titan taken by Cassini in January 2012. (Credit: NASA/JPL-Caltech/Space Science Institute)

Dr. Kelly Miller from the South West Research Institute and Lead author of a paper about Titan’s atmosphere said “While just 40% the diameter of the Earth, Titan has an atmosphere 1.5 times as dense as the Earth’s, even with a lower gravity, walking on the surface of Titan would feel a bit like scuba diving!” To try and understand the existence of methane in the atmosphere Southwest Research Institute joined forces with the Carnegie Institution for Science to conduct some experiments with interesting results. 

ASA’s Cassini spacecraft looks toward the night side of Saturn’s largest moon and sees sunlight scattering through the periphery of Titan’s atmosphere and forming a ring of color. Credit: NASA/JPL-Caltech/Space Science Institute

A model was proposed in 2019 that suggested just how the methane could be replenished over the years. It theorised that large amounts of organic materials are heated by the moon’s interior, releasing nitrogen and carbon based gas like methane. The gas seeps to the surface where it replenishes the atmosphere. The theory was developed off the back of data from NASA’s Cassini-Huygens spacecraft which arrived at the Saturnian system in 2004. It explored it for the next 13 years while the Huygens probe dropped onto the surface of Titan in 2005. 

Artist depiction of Huygens landing on Titan. Credit: ESA

The team led by Miller arranged experiments to heat up organic materials to temperatures up to 500 degrees Celsius at pressures up to 10 kilobars. This simulated the conditions found under the surface of Titan. The process generated sufficient quantities of methane that would enable Titan’s atmosphere to be replenished to the levels we observe today. 

To learn more about the atmosphere of Titan, NASA plans to launch another spacecraft to the Saturnian system in 2028. It’s been called Dragonfly and involves a quadcopter that will, like Ingenuity did on Mars, explore Titan’s atmosphere. The thick atmosphere and low surface gravity make it an ideal place to explore from the air. Not only will it help us to understand more about the atmospheric conditions but it will help to assess the moon’s habitability by analysing prebiotic molecules and searching for signs of past, or even present life! 

Source : SwRI-designed experiments corroborate theory about how Titan maintains its atmosphere

The post How Can Titan Maintain its Atmosphere? appeared first on Universe Today.

On Thursday January 30th, astronauts Suni Williams and Butch Wilmore are doing a 6.5-hour spacewalk outside the International Space Station. Among other goals, they’ll be collecting surface samples from the station to analyze for the presence of microbes.

The ISS “surface swab” is part of the ISS External Microorganisms project. It was developed to understand how microorganisms are transported by crew members to space. It also seeks to understand what happens to those “mini-critters” in the space environment.

The “bugs” that the two astronauts bring back in for analysis will come from areas on the space station near life-support system vents. The idea is to figure out if the station releases those microbes through the vents. Scientists also want to know the size of the release population, and where else they show up on the station.

The Microbes Experiment

Researchers seek to understand how microbes exist and thrive in space and planetary environments. At the moment, the best analog for those is on the ISS, particularly its exterior. So, when microbes find their way out, people want to know how long they survive the radiation. Do quick temperature changes affect them? What else happens to them? Also, scientists want to know if microbes manage to reproduce and how the environment changes that.

Samples from the ISS surface get frozen in special containers and eventually get returned to Earth. Once in the lab, they’re analyzed using culture-independent techniques such as next-generation deoxyribonucleic acid (DNA) sequencing to measure microbial community. Functional pathways in these microbial communities are characterized by targeting multi-gene analysis. This approach allows for a comprehensive assessment of the microbial diversity and metabolic function without cultivation. The samples collected at different locations or during different EVA opportunities allow investigators to map the microbial diversity of ISS external surfaces.

A member of the ISS External Microorganisms payload development team demonstrates removing a swab from the sampling caddy that is used by an astronaut during a spacewalk. A crew member uses the swabbing tool to collect microbes in samples from the exterior surface of the International Space Station at various locations. Results could inform preparations for future human exploration missions to the Moon and Mars. Credit: NASA. Why Test for Microbes?

While people have been flying to and from space for decades now, the scientific community still has significant gaps in knowledge about understanding how microbes get released, how they thrive, and what their life cycles are in space. In particular, the ISS sees many visiting vehicles each year, and astronauts move around freely inside. Those activities likely increase the microbe population both inside and out.

Collecting microbes and analyzing them allows scientists to assess the types and numbers of microorganisms living on the outer shell of a spacecraft. The larger goal is to supply more information under the guidelines of NASA’s policy on Planetary Protection Requirements for Human Extraterrestrial missions. There are still many questions to be answered, including: what are the acceptable levels of microbial life? Which ones make it out through the vents? What are acceptable contamination rates? While NASA has designed this mission to answer those and other questions, the Russian space agency Roscosmos is also making similar investigations to sample the Russian side of the station. That resulted in the discovery of non-spore-forming bacteria growing on the outer skin of the station.

The results of microbe analysis from this and other microorganism collections could affect spacecraft design and spacesuit changes. This becomes doubly important when people venture out onto the surface of Mars, for example. While we see no direct evidence of life there now, it could be there and likely existed in the past. Not only do we want to avoid contaminating astronauts with that life, we also want to avoid (as much as possible) bringing Earth life to Mars. This same research has applications in other fields, such as agriculture and pharmaceuticals.

Info on the Space Walk

This isn’t the first time the ISS has been tested for exterior microbial life, and the long-term study is necessary. The planned sampling to be mission undertaken by Williams and Wilmore is officially called Spacewalk 92 and should start at 8 a.m. on January 30th. NASA will provide live coverage of the walk (check here for more information), which will also conduct some other maintenance on the station along with the sampling activities.

For More Information

Astronauts Set to Swab the Exterior of Station for Microbial Life
Space Station Research Explorer

The post Astronauts are Going to Check if There are Microbes on the Outside of the Station appeared first on Universe Today.

When an exoplanet is discovered, scientists are quick to describe it and explain its properties. Now, we know of thousands of them, many of which are members of a planetary system, like the well-known TRAPPIST-1 family of planets.

Patterns are starting to emerge in these exoplanetary systems, and in new research, a team of scientists says it’s time to start classifying exoplanet systems rather than just individual planets.

The paper is “Architecture Classification for Extrasolar Planetary Systems,” and it’s available on the pre-print site arxiv.org. The lead author is Alex Howe from NASA’s Goddard Space Flight Center. The authors say it’s time to develop and implement a classification framework for exoplanet systems based on our entire catalogue of exoplanets.

“With nearly 6000 confirmed exoplanets discovered, including more than 300 multiplanet systems with three or more planets, the current observational sample has reached the point where it is both feasible and useful to build a classification system that divides the observed population into meaningful categories,” they write.

The authors explain that it’s time for a systemic approach to identifying patterns in exoplanet systems. With almost 6,000 exoplanets discovered, scientists now have the data to make this proposition worthwhile.

Artist’s rendition of a variety of exoplanets featured in the new NASA TESS-Keck Survey Mass Catalog, the largest, single, homogenous analysis of TESS planets released by any survey thus far. Credit: W. M. Keck Observatory/Adam Makarenko

What categories do the authors propose?

The first step is necessarily broad. “The core of our classification system comes down to three questions for any given system (although, in several cases, we add additional subcategories). Does the system have distinct inner and outer planets?” the authors write.

Next comes the question of Jupiters. “Do the inner planets include one or more Jupiters?” After that, they ask if the inner planets contain any gaps with a period ratio greater than 5. That means if within the gaps between the inner planets, are there any instances where the ratio of the orbital periods of two hypothetical planets occupying those gaps would exceed 5? Basically, that boils down to asking if the absence of planets in specific regions in the inner solar system is related to unstable orbits.

These three questions are sufficient to classify nearly all of the exoplanet systems we’ve discovered.

“We find that these three questions are sufficient to classify ~97% of multiplanet systems with N ?3 planets with minimal ambiguity, to which we then add useful subcategories, such as where any large gaps occur and whether or not a hot Jupiter is present,” the authors write.

The result is a classification scheme that divides exoplanet systems into inner and outer regimes and then divides the inner regimes into dynamical classes. Those classes are:

• Peas-in-a-pod systems where the planets are uniformly small
• Warm Jupiter systems containing a mix of large and small planets
• Closely-space systems
• Gapped systems

There are further subdivisions based on gap locations and other features.

“This framework allows us to make a partial classification of one- and two-planet systems and a nearly complete classification of known systems with three or more planets, with a very few exceptions with unusual dynamical structures,” the authors explain.

In summary, the classification scheme first divides systems into inner and outer planets (if both are detected). Systems with more than three inner planets are then classified based on whether their inner planets include any Jupiters and whether (and if so, where) their inner planets include large gaps with a period ratio >5. Some systems have other dynamical features that are addressed separately from the overall classification system.

This is a quick reference chart for the new system of classifying planetary system architectures, with representative model systems for each category. Each row is one planetary system, where the horizontal spacing corresponds to the orbital period, and the point sizes correspond to planet sizes. Colours correspond to planet type: Jupiters (>6 Earth radii, red), Neptunes (3.5-6 Earth radii, gold), Sub-Neptunes (1.75-3.5 Earth radii, blue), and Earths (<1.75 Earth radii, green). Image Credit: Howe et al. 2025.

The classification system is based on NASA’s Exoplanet Archive, which listed 5,759 exoplanets as of September 2024. It’s a comprehensive archive, but it also contains some questionable exoplanets drawn from papers that can sometimes be inaccurate, poorly constrained, or even contradicted by subsequent papers. The researchers filtered their catalogue to remove data they considered unusable. As a result, they removed 2% of the exoplanets in their archive.

They also filtered out some of the stars because of incomplete data, which meant that planets around those stars were removed, too. Planets orbiting white dwarfs and pulsars were removed, as were planets orbiting brown dwarfs. The idea was to “represent the population of planets orbiting main sequence stars,” as the authors explain.

This table from the research shows the number of confirmed planetary systems by multiplicity after the researchers applied all of their filters. Image Credit: Howe et al. 2025.

As the table above makes clear, most exoplanet systems contain only a single detected planet. 78% of them host only one planet, often a hot Jupiter, though selection effects play a role in the data. Jupiters are a key planet type in nature and in the classification scheme.

“As expected, Jupiter-sized planets are far less likely to occur in multiplanet systems at periods of <10 days and virtually none do at <5 days, as indicated by the near-coincidence of the two Jupiter distributions at those periods. Meanwhile, roughly half of all other planet types and even a third of Jupiters at periods >10 days occur in multiplanet systems,” the authors explain.

This figure shows the cumulative distributions of confirmed exoplanets with orbital periods. It compares the total numbers of planets (dashed) to those in single-planet systems (solid). “Hot Jupiters show far fewer companions than other planet types, as illustrated by the near-coincidence of the two Jupiter distributions at <10 days,” the authors explain.

The classification system does a good job of capturing the large majority of exoplanet system architectures. However, there are some oddballs, including the WASP-148 system, the only known system with a hot Jupiter and a nearby Jupiter companion. “Given the high detection probability of such a companion and the fact that 10 hot Jupiters are known to have smaller nearby companions, this points to an especially rare subtype of system and potential unusual migration processes,” the authors write.

This table presents the seven oddballs in NASA’s Exoplanet Archive according to the classification scheme. Image Credit: Howe et al. 2025.

Though exoplanet systems seem to be very diverse, this classification scheme shows that there’s a lot of uniformity in the patterns. Even though there’s a large diversity of planet types, most inner systems are either peas-in-a-pod systems or warm Jupiter systems. “Only a tiny minority of N ?3 systems (9 out of 314) prove difficult to classify into one of these two categories,” the authors write.

Like much exoplanet science, this system is hampered by detection biases. We struggle to detect small planets like Mars with our current capabilities. There could be more of them hiding in observed exoplanet systems. There are more detection problems, too, like planets on long orbits. However, the scheme is still valuable and interesting.

“This classification scheme provides a largely qualitative description of the architectures of currently observed multiplanet systems,” the authors explain. “The next step is to understand how such systems are formed, and, perhaps equally important, why other dynamically plausible systems are not present in the database.”

One outcome concerns the peas-in-a-pod systems. Since they’re so prevalent, scientists are keen to develop theories on their formation.

The system also has implications for habitability. The outcomes show that in peas-in-a-pod systems, the planets are often too close to main sequence stars to be habitable. Conversely, these same types of systems around M-dwarfs likely have planets in their stars’ habitable zones. “This may suggest that the majority of habitable planets reside around lower-mass stars in peas-in-a-pod systems,” the authors explain. That brings up the familiar problem of flaring and red dwarf habitability.

Another problem this classification scheme highlights concerns super-Earth habitability. “Most planets in peas-in-a-pod systems are super-Earths, rather than Earth-sized, and may be too large for the canonical definition of a habitable planet,” the authors write.

In their conclusion, the researchers explain that exoplanet systems seem to have clear organizing principles that we can use to classify distinct types of solar systems.

“Though far from complete, we believe this classification provides a better understanding of the population as a whole, and it should be fertile ground for future studies of exoplanet demographics and formation,” the researchers conclude.

The post It’s Time to Start Classifying Exoplanetary Systems appeared first on Universe Today.

Astronomers have found some pretty wild exoplanets. Some are balls of lava the temperature of hell, one is partially made of diamond, and another may rain molten iron. However, not all exoplanets are this extreme. Some are rocky, roughly Earth-sized worlds in the habitable zones of their stars.

Could simple Earth life survive on some of these less extreme worlds?

We currently describe a solar system’s habitable zone by liquid water. If a planet is at the right distance range from its star to host stable surface water, we consider it to be in the habitable zone. However, new research is taking a different approach by emphasizing the role a planet’s atmosphere plays in habitability.

The scientists behind this research tested their idea by seeing if microbes could survive on simulated worlds.

The new research is “The Role of Atmospheric Composition in Defining the Habitable Zone Limits and Supporting E. coli Growth.” It’s available on the pre-print site arxiv.org. The lead author is Asena Kuzucan, a post-doctoral researcher in the Department of Astronomy at the University of Geneva in Switzerland.

We’ve discovered close to 6,000 exoplanets in about 4,300 planetary systems. Our burgeoning catalogue of exoplanets makes us wonder about life. Is there life elsewhere, and are any of these thousands of exoplanets habitable?

Some have teased the possibility. TRAPPIST1-e and Proxima Centauri b are both rocky planets in the habitable zones of their stars. TOI-700 d orbits a small, cool star and may be in its habitable zone. There are many others.

The simple definition of the habitable zone is restricted to a planet’s distance from its star and if liquid water can persist on its surface at that distance. However, scientists know that a planet’s atmosphere plays a large role in habitability. A thick atmosphere on a planet outside the habitable zone could help it maintain liquid water.

“Each atmosphere uniquely influences the likelihood of surface liquid water, defining the habitable zone (HZ), the region around a star where liquid water can exist,” the authors write. Liquid water doesn’t guarantee that a world is habitable, however. In order to understand exoplanet habitability better, the researchers followed a two-pronged approach.

They started by estimating exoplanet surface conditions near the inner edge of a star’s HZ with different atmospheric compositions.

Next, they considered if Earth microbes could survive in these environments. They did lab experiments on E. coli to see how or if they could grow and survive. They focused on the different compositions of gas in these atmospheres. The atmospheric compositions were standard (Earth) air, pure CO2, N2-rich, CH4-rich, and pure molecular hydrogen.

Their experiments used 15 separate bottles, 3 for each of the 5 atmospheric compositions. Each bottle was inoculated with E. coli K-12, a laboratory strain of E. coli that is a cornerstone of molecular biology studies.

This simple graphic shows the atmospheric composition of the test bottles. Each bottle is a combination of different atmospheric composition and pressure. LB stands for Lysogeny broth, a nutrient source for E. coli K12. image Credit: Kuzucan et al. 2025.

“This innovative combination of climate modelling and biological experiments bridges theoretical climate predictions with biological outcomes,” they write in their research.

Along with their laboratory experiments, the team performed a series of simulations with different atmospheric compositions and planetary characteristics. “For each atmospheric composition we simulate, water is a variable component that can condense or evaporate as a function of the pressure/temperature conditions,” they write. For each atmospheric composition, they simulated planets at different orbital distances in order to define the inner edge of the HZ. They also varied the atmospheric pressure.

“Using 3D GCM (General Circulation Model) simulations, this study provides a first look at how these atmospheric compositions influence the inner edge of the habitable zone, offering valuable insights into the theoretical limits of habitability under these extreme conditions,” the authors explain.

This table from the research shows the planetary and stellar characteristics used in the GCM simulations. Image Credit: Kuzucan et al. 2025.

“Our findings indicate that atmospheric composition significantly affects bacterial growth patterns, highlighting the importance of considering diverse atmospheres in evaluating exoplanet habitability and advancing the search for life beyond Earth,” they write.

This figure shows the cell count for E. coli K12 in each simulated atmosphere. Image Credit: Kuzucan et al. 2025.

E. coli did surprisingly well in varied atmospheric compositions. Though there was a lag following inoculation as the E. coli adapted, cell density increased in some of the tests. The hydrogen-rich atmosphere did surprisingly well.

“By the first day after inoculation, cell densities had increased in standard air, CH4-rich, N2-rich, and pure H2 atmospheres,” the authors write. “While cell densities increased similarly in standard air, CH4-rich, and N2-rich atmospheres, a slightly stronger increase was observed in the pure H2 atmosphere. The rapid adaptation of E. coli to pure H2 suggests that hydrogen-rich atmospheres can support anaerobic microbial life once acclimatization occurs.”

Conversely to the H2 results, the CO2 results lagged. “Pure CO2, however, consistently presented the most challenging environment, with significantly slower growth,” the paper states.

Their results suggest that planets with anaerobic atmospheres that are dominated by H2, CH4, or
N2 could still support microbial life, even if the initial growth is slower than it is in Earth’s air. “The ability to adapt to less favourable conditions implies that life could persist on such planets, given sufficient time for acclimatization,” the authors write.

The CO2-rich atmosphere is the outlier in this work. “The consistently poor growth in pure CO2 highlights the limitations of this gas in supporting life, particularly for heterotrophic organisms like E. coli,” Kuzucan and her co-researchers write. However, the authors point out that some life forms can make use of CO2 as a carbon source in some environments. They explain that planets with these types of atmospheres could still host organisms adapted to them, like chemotrophs or extremophiles.

This work combines atmospheric and biological factors to understand exoplanet HZs. “One of our key objectives was to define the limits of the HZ for planets dominated by H2 and CO2 using 3D climate modelling, specifically the Generic PCM model,” the authors explain.

They found that H2 atmospheres have a warming effect, “pushing the inner edge of the HZ to further orbital distances than CO2-dominated atmospheres.” It could extend out to 1.4 AU at 5 bar, while the CO2 atmospheres at the same pressure were limited to 1.2 AU. “This demonstrates the profound impact of atmospheric composition on planetary climate and highlights how H2 atmospheres can extend the
habitable zone further from their host stars,” the researchers write.

Some of the atmospheres they tested are not likely to persist in nature, but the results are still scientifically valuable.

“Although some of the atmospheric scenarios presented here (1-bar H2 and CO2) are simplified, and
may not persist over geological timescales due to processes like hydrogen escape and carbonate-silicate cycling, they nonetheless provide valuable insights into the radiative effects of these gases on habitability,” write the authors.

We know atmospheres are extremely complex, and this research supports that. It also shows how resilient Earth life can be. “Overall, these results highlight both the resilience of E. coli in adapting to diverse atmospheric conditions and the critical role atmospheric composition plays in determining
microbial survival,” the authors explain in their conclusion. Though the authors acknowledge that their findings are rooted in an Earth-centric framework, the results have broader implications. Life could likely thrive in wildly different atmospheric compositions and conditions, according to these results.

“Thus, our study highlights the importance of atmospheric composition and pressure for habitability while acknowledging the limitations of our Earth-centric perspective,” they write.

“By exploring both atmospheric conditions and microbial survival, we gain a deeper understanding of the complex factors that influence habitability, paving the way for future research on the potential for life beyond our solar system.”

The post How Well Could Earth Life Survive on Exoplanets appeared first on Universe Today.

The event horizon is a fascinating part of a black hole’s anatomy. In 2017, telescopes around the world gathered data on the event horizon surrounding the supermassive black hole at the heart of M87. This was the first time we had ever seen an image of such a phenomenon. Since then, 120,000 more images of the region have been captured and, as astronomers sift through the data, their model of M87’s event horizon has evolved. 

Black holes, formed from the collapse of massive stars or in some cases through other processes, are regions of space-time where gravity is so intense that it warps the fabric of the universe. The event horizon is the boundary surrounding a black hole, beyond which nothing—not even light—can escape its gravitational pull. It marks the point of no return for any matter or radiation that gets too close. Within the event horizon, the curvature of space-time becomes infinite, leading to a singularity, a point where density and gravity reach extremes that modern physics and mathematics struggle to model. The event horizon’s properties are critical to understanding black holes, as it represents the outermost layer hiding everything within. 

This artist’s impression shows a black hole about 800 million years after the Big Bang, during one of its short periods of rapid growth. Image Credit: Jiarong Gu

One such object sits at the centre of most galaxies and in particular at the centre of M87, a massive elliptical galaxy 53 million light years away. It’s approximately 120,000 light years across with an estimated trillion stars. At its core is a supermassive black hole which weighs in at about 6.5 billion times the mass of the Sun. It was this object which was imaged back in 2017 for the first time. 

The jet emerging from the galactic core of M87. NASA/STScI/AURA.

Since that first image of the event horizon around the M87 black hole, over 120,000 images have been used to analyse how the horizon has evolved since the first images were captured. Like all black holes, M87’s has a rotational axis and it is this, that the images have revealed something unexpected. 

A team of astronomers have confirmed that the axis points away from the Earth and have shown that the accretion disk suffers turbulence. Compared to images from 2017, the accretion disk has brightened and it is thought the turbulence in the accretion disk is the cause. As assistant professor Hung-Yi Pu from National Taiwan Normal University explains “the black hole accretion environment is turbulent and dynamic. Since we can treat the 2017 and 2018 observations as independent measurements, we can constrain the black hole’s surroundings with a new perspective.”

The accretion disk around M87* (as the black hole is referred to) is a swirling disk of gas and dust that orbits around the black hole before being pulled in. The disk forms when matter is stripped off nearby stars or from interstellar gas before spiralling in to the black hole under its immense gravitational pull. As the material accelerates in the disk and gets compressed, it heats up to millions of degrees, emitting radiation across the electromagnetic spectrum. It’s this radiation that often reveals the presence of a black hole.

3D rendering of a rapidly spinning black hole’s accretion disk and a resulting black hole-powered jet. Credit: Ore Gottlieb et al. (2024)

The discoveries from the super computer generated images reveal more about the dynamics in the regions surrounding a black hole. They find that material spiralling into a black hole from afar can either flow in the direction of the black hole’s rotation or in the opposite direction. 

Source : M87 One Year Later: Catching the Black Hole’s Turbulent Accretion Flow

The post Watching the Changing M87 Black Hole Event Horizon appeared first on Universe Today.

A classic scene from several high sci-fi movies and shows is when the characters approach their new spaceship in space for the first time. It is typically attached to a massive structure – think of the Kuat Drive Yards in Star Wars or the Utopia Planitia Fleet Yards around Mars in Star Trek. These gigantic structures play a role akin to what dry docks do for modern navies – they allow for the construction of ships in a relatively controlled environment with access to tools and equipment specialized for their construction. That is the idea behind a new NASA Institute for Advanced Concepts (NIAC) grant to ThinkOrbital, a company specializing in In-space assembly, manufacturing, and construction (ISAM&C). Their idea is to build a “Construction Assembly Destination” in orbit to build spacecraft in space.

That might seem like a lofty goal, but ThinkOrbital has some pedigree in doing ISAM&C tasks that no one else has done before. In May 2024, they launched and successfully tested the first-ever weld in space. The mission flew on a Falcon 9, spot-welded together some quarter-inch pieces of aluminum, and returned it to Earth, where the welds were closely examined.

They used a method called electron beam welding, which has several advantages for use in space. First, it doesn’t require as much power as a traditional arc welder—only around 2KW, equivalent to a household iron. Second, it doesn’t create a lot of heat, which can degrade the metal being welded and cause issues like splintering, which can become dangerous in zero-gravity situations.

Video describing the ThinkOrbital welder launch and test.
Credit – ThinkOrbital YouTube Channel

Doing a simple weld is a far cry from building an entire floating dry dock, but it is a step in that direction. Vojtech Holub, ThinkOrbital’s co-founder and CIO, said in an interview with Fraser that the company had actually submitted a proposal to NIAC for a more moderate step in the development of ISAM&C technology. However, the idea for a space station four times the size of the ISS “was not deemed futuristic enough.”

That rejection inspired the company to go bigger – by suggesting an entire orbital construction platform. In the interview, Dr. Volub talks about creating an interior space of 4,000 cubic meters by launching exterior plates akin to the hexagons on a soccer ball and welding them together in space using the company’s existing welder technology. In theory, if the process can be repeated, you could even build a large enough station to make something “up to [the size of] an Imperial Star Destroyer,” according to Dr. Holub.

There are some obvious difficulties in scaling up to that level, including requiring thicker plates and how to introduce gravity to any human occupants. Still, the general idea is scalable well beyond anything currently in orbit. As part of the NIAC grant, Dr. Holub and his team will have to develop a concept of operations (or CONOPS) for the development of the station, including how many launches it would take, what kind of structural loads it would be under, and how it would be assembled once it was up there.

The Orb2 was the original concept, introduced in a paper by Vojtech Holub, that spawned the idea of ThinkOrbital.
Credit – ThinkOrbital YouTube Channel

With answers to those questions in hand, ThinkOrbital would potentially be given a Phase II NIAC grant that would allow them to start building some prototypes to de-risk the technology. But they’ve got to complete Phase I first and compete with plenty of other ideas that NIAC has selected. If they are picked for a Phase II grant, though, it could move the start-up from concept to the reality of building a massive space for constructing space infrastructure – something humanity will need when it expands more throughout the solar system.

Learn More:
NASA / ThinkOrbital – Construction Assembly Destination
Vojtech Holub – Orb2: Spherical Space Station Designed for Single Launch and On-Orbit Assembly
UT – Blue Origin Announces the “Orbital Reef,” the Space Station they Plan to Build in Orbit
UT – Gateway Foundation Gives a Detailed Update on its Voyager Station Concept

Lead Image:
Artist concept highlighting the novel approach proposed by the 2025 NIAC awarded selection of Construction Assembly Destination
Credit – NASA/Ryan Benson/ThinkOrbital

The post Space Shipyards Could Build Missions in Orbit appeared first on Universe Today.

Exoplanets have captured the imagination of public and scientists alike and, as the search continues for more, researchers have turned their attention to the evolution of metallicity in the Milky Way. With this answer comes more of an idea about where planets are likely to form in our Galaxy. They have found that stars with high-mass planets have higher metallicity than those with lower amounts of metals. They also found that stars with planets tend to be younger than stars without planets. This suggests planetary formation follows the evolution of a galaxy with a ring of planet formation moving outward over time. 

The search for exoplanets has largely been one of surveying nearby stars.  That generally means we are exploring stars in our region of the Galaxy. As technology develops, our ability to detect them improves and to date, nearly 6,000 planets have been discovered around other stars. A number of different techniques have been used to find them such as the transit method – which detects the dimming of a star’s light due to the presence of the passage of a planet, or the radial velocity method which measures the wobble of a star due to the gravitational tug of a planet. 

This artist’s impression depicts the exomoon candidate Kepler-1625b-i, the planet it is orbiting and the star in the centre of the star system. Kepler-1625b-i is the first exomoon candidate and, if confirmed, the first moon to be found outside the Solar System. Like many exoplanets, Kepler-1625b-i was discovered using the transit method. Exomoons are difficult to find because they are smaller than their companion planets, so their transit signal is weak, and their position in the system changes with each transit because of their orbit. This requires extensive modelling and data analysis.

One key aspect of planetary development in the Galaxy is the presence of metals (elements heavier than hydrogen and helium.) known as metallicity. These elements are formed during the life cycle of a star, especially during supernova explosions. They are scattered through space and form part of the interstellar medium. Understanding the abundance and distribution of metals provides an insight into the age, history and formation rates of stars and planets. 

The Milky Way. This image is constructed from data from the ESA’s Gaia mission that’s mapping over one billion of the galaxy’s stars. Image Credit: ESA/Gaia/DPAC

A team of researchers led by Joana Teixeira from the University of Porto in Portugal have been exploring something known as the Galactic Birth Radii (rBirth) This term relates to the distance from galactic centre that stars and therefore planets are forming. Using photometric, spectroscopic and astrometric data, the team were able to estimate the ages of two groups of stars, those with planets and those without. This enabled them to rBirth for exoplanets based upon the original star positions (having calculated them from their age and levels of metals present within.)

The results of the analysis showed that stars hosting planets had a higher [Fe/H], are younger and were born closer to the centre of the galaxy than those without (Fe/H refers to the amount of iron relative to the amount of hydrogen in a star or galaxy, where the Sun is [Fe/H]=0.3.) The team went further to state that from one data set (from the Stellar Parameters of Stars with Exoplanets Catalog,) the results suggest that stars hosting high mass planets have a different iron to hydrogen radio and age distribution than stars with at least one low mass planet and those with only low mass planets. 

The ESA/NASA Solar Orbiter has given us our highest resolution images of the Sun ever. They show us sunspots, plasma, and magnetic fields, and more. Image Credit: ESA

The research reveals that high mass planets or in other words terrestrial planets tend to form around stars with higher [Fe/H] and younger stars compared to low mass. Similarly, those with a mixture of high and low mass planets also formed around higher [Fe/H], young stars. 

It’s an interesting study worthy of further investigations. Understanding that Earth-like planets tend to form around star systems that formed around the inner regions of the Galaxy. Here the supply of metals is more abundant and, even though the stellar systems can migrate to outer regions of the Milky Way it gives a better focus on the hunt for planetary systems beyond our own. 

Source : Where in the Milky Way Do Exoplanets Preferentially Form?

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Astronomers have found two planets around two separate stars that are succumbing to their stars’ intense heat. Both are disintegrating before our telescopic eyes, leaving trails of debris similar to a comet’s. Both are ultra-short-period planets (USPs) that orbit their stars rapidly.

These planets are a rare sub-class of USPs that are not massive enough to hold onto their material. Astronomers know of only three other disintegrating planets.

USPs are known for their extremely rapid orbits, some completing an orbit in only a few hours. Since they’re extremely close to their stars, they’re subjected to intense heat, stellar radiation, and gravity. Many USPs are tidally locked to their star, turning the star-facing side into an inferno. USPs seldom exceed two Earth radii, and astronomers think that about 1 in 200 Sun-like stars has one. They were only discovered recently and are pushing the boundaries of our understanding of planetary systems.

There are plenty of unanswered questions about USPs. Their formation mechanism is unclear, though they likely migrated to their positions rather than formed there. They’re difficult to observe because of their proximity to their stars, making questions about their structures difficult to answer.

Fortunately, two separate teams of researchers have spotted the two disintegrating USPs. As they spill their contents out into space in tails, they’re giving astronomers an opportunity to see what’s inside them.

The new observations are in two new papers available at the pre-press site arxiv.org. One is “A Disintegrating Rocky Planet with Prominent Comet-like Tails Around a Bright Star.” The lead author is Marc Hon, a postdoctoral researcher at the MIT TESS Science Office. This paper is referred to hereafter as the MIT study.

“We report the discovery of BD+054868Ab, a transiting exoplanet orbiting a bright K-dwarf with a period of 1.27 days,” the authors write. The TESS spacecraft found the planet, and its observations “reveal variable transit depths and asymmetric transit profiles,” the paper states. Those are characteristics of dust coming from the doomed planet and forming tails: one on the leading edge and one on the trailing edge. Dust particle size in each tail is different, with the leading trail containing larger dust and the trailing tail containing finer grains.

This figure from the team’s modelling illustrates some of their findings. “A view from above the planetary orbit, looking down at the x ? y plane in which the planet is orbiting counterclockwise. The trails indicate the accumulated trajectories of the dust grains over time. There are two distinct trails that correspond to the leading and trailing dust tails,” the authors explain. The planet is not to scale in this image, but the host star is. Image Credit: Hon et al. 2025.

“The rate at which the planet is evaporating is utterly cataclysmic, and we are incredibly lucky to be witnessing the final hours of this dying planet’,'”

Marc Hon, MIT TESS Science Office

“The disintegrating planet orbiting BD+05 4868 A has the most prominent dust tails to date, “said lead author Hon. “The dust tails emanating from the rapidly evaporating planet are gigantic. Its length of approximately 9 million km encircles over half the planet’s orbit around the star every 30 and a half hours,” he added.

The MIT study shows that the planet is losing mass at the rate of 10 Earth masses of material per billion years. Since the object is probably only roughly the size of Earth’s Moon, it will be totally destroyed in only a few million years. “The rate at which the planet is evaporating is utterly cataclysmic, and we are incredibly lucky to be witnessing the final hours of this dying planet,” said Hon.

The host star is probably a little older than the Sun and has a companion red dwarf separated by about 130 AU. The authors think that the planet is a great candidate for follow-up studies with the JWST. Not only is the star bright, but the transits are deep. Because of the leading and trailing tails, the transits can last up to 15 hours.

The Las Cumbres Observatory captured this image of the two stars. The main sequence star is on the right, and its red dwarf companion is on the left. Image Credit: LCO/Hon et al. 2025.

“The brightness of the host star, combined with the planet’s relatively deep transits (0.8?2.0%), presents BD+054868Ab as a prime target for compositional studies of rocky exoplanets and investigations into the nature of catastrophically evaporating planets,” they explain.

“What’s also highly exciting about BD+05 4868 Ab is that it has the brightest host star out of the other disintegrating planets —about 100 times brighter than K2-22—establishing it as a benchmark for future disintegrating studies of such systems,” said Avi Shporer, a Research Scientist at the MIT Kavli Institute for Astrophysics and Space Research and a co-author of the MIT paper. “Prior to our study, the three other known disintegrating planets were around faint stars, making them challenging to study,” he added.

The second paper is “A Disintegrating Rocky World Shrouded in Dust and Gas: Mid-IR Observations of K2-22b using JWST.” The lead author is Nick Tusay, a PhD student at Penn State working in the Center for Exoplanets and Habitable Worlds. This paper is hereafter referred to as the Penn State study.

“The effluents that sublimate off the surface and condense out in space are probably representative of the formerly interior layers convectively transported to the molten surface,” the authors write. In this work, astronomers were able to observe its debris with the JWST’s MIRI and also with other telescopes. The observations show that the material coming from the USP is not likely to be iron-dominated core material. Instead, they’re “consistent with some form of magnesium silicate minerals, likely from mantle material,” the authors explain.

“These planets are literally spilling their guts into space for us, and with JWST we finally have the means to study their composition and see what planets orbiting other stars are really made of,” said lead author Tusay.

We can’t see what’s inside the planets in our Solar System, though seismic waves and other observations give scientists a pretty good idea about Earth’s interior. By examining the entrails coming from K2-22b, astronomers are learning not only about the planet but, by extension, about other rocky planets. The irony is that they’re so far away.

“K2-22b has an asymmetric transit profile, as the planet’s dusty cloud of effluents comes into view in front of the star, showing evidence of extended tails like a comet.”

“It’s a remarkable and fortuitous opportunity to
understand terrestrial planet interiors.”

Professor Jason Wright, Astronomy and Astrophysic, Penn State

“It’s remarkable that directly measuring the interior of planets in the Solar System is so challenging—we have only limited sampling of the Earth’s mantle, and no access to that of Mercury, Venus, or Mars—but here we have found planets hundreds of light years away that are sending their interiors into space and backlighting them for us to study with our spectrographs,” said Jason Wright, Professor of Astronomy and Astrophysics, co-author of the Penn State study, and Tusay’s PhD supervisor. “It’s a remarkable and fortuitous opportunity to understand terrestrial planet interiors,” he added.

While TESS discovered the disintegrating planet in the previous paper, Kepler found this one during its extended K2 mission. This one orbits its M-dwarf star in only 9.1 hours. Evidence of its tail is in the variability of its light curve. “The dramatic variability in lightcurve transit depth (0–1.3%) combined with the asymmetric transit shape suggests we are observing a transient cloud of dust sublimating off the surface of an otherwise unseen planet,” the MIT paper states.

As this figure from the research shows, each of K2-22b’s transits lasts about 46 minutes. Each blue point represents 8 minutes. Image Credit: Tusay et al. 2025.

According to the authors, this could be the first time we’ve seen outgassing from a vaporizing planet. “The shorter MIRI wavelength features … may constitute the first direct observations of gas features from an evaporating planet,” the paper states.

“Unexpectedly, the models that best fit these measurements seem to be ice-derived species (NO and CO2),” the authors write. Though the spectrum is broadly consistent with a rocky body, the presence of NO and CO2 is a bit of a curveball. These materials are more similar to icy bodies like comets rather than rocky planets.

“It was actually sort of a ‘who-ordered-that?’ moment,” Tusay said about finding the icy features. For this reason, the researchers are eager to point the JWST at the planet again to obtain more and better data. Multiple pathways can generate these results, and only better data can help astronomers determine what’s going on.

According to the authors, the wavelength features in the spectrum “may constitute the first direct observations of gas features from an evaporating planet.” Rather unexpectedly, the results indicate ice-derived chemical species. Image Credit: Tusay et al. 2025.

Though we’re in the early days of observing planets like this one, scientists still have some expectations. These results defy those expectations since many expected to find only the iron-core remnants of these USPs.

“We didn’t know what to expect,” said Wright, who also co-authored an earlier study on how to use JWST to probe these exoplanetary tails. “We were hopeful they might still have their mantles, or potentially even crust material that was being evaporated. JWST’s mid-infrared spectrograph MIRI was the perfect tool to check, because crustal, silicate mantle, and iron core materials would all transmit light in different ways that JWST could distinguish spectroscopically,” Wright added.

Next, both teams of scientists hope to point the JWST at BD+05 4868 Ab from the MIT study. Its star is far brighter than the other stars known to host disintegrating USPs. A bright light source makes it much easier for the JWST to get stronger results.

“What’s also highly exciting about BD+05 4868 Ab is that it has the brightest host star out of the other disintegrating planets —about 100 times brighter than K2-22—establishing it as a benchmark for future disintegrating studies of such systems,” said Avi Shporer, a Research Scientist at the MIT Kavli Institute for Astrophysics and Space Research and a co-author of the MIT project. “Prior to our study, the three other known disintegrating planets were around faint stars, making them challenging to study,” he added.

When the JWST was launched, it wasn’t aimed at observing disintegrating exoplanets. But this research shows off a new way of using the powerful telescope. Surprises like this are a part of every new telescope or observing effort, and researchers often look forward to them.

“The data quality we should get from BD+05 4868 A will be exquisite,” said Shporer. “These studies have proven the validity of this approach to understanding exoplanetary interiors and opened the door to a whole new line of research with JWST.”

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Exoplanet exploration has taken off in recent years, with over 5500 being discovered so far. Some have even been in the habitable zones of their stars. Imaging one such potentially habitable exoplanet is the dream of many exoplanet hunters, however, technology has limited their ability to do that. In particular, one specific piece of technology needs to be improved before we can directly image an exoplanet in the habitable zone of another star – a starshade. Christine Gregg, a researcher at NASA Ames Research Center, hopes to contribute to the effort of developing one and has received a NASA Institute for Advanced Concepts (NIAC) grant as part of the 2025 cohort to work on a star shade that is based on a special type of metamaterial.

To understand the goal of Dr. Gregg and her team, it’s best first to understand what starshades do and what’s holding them back from being deployed. A starshade is designed to float in tandem with a space telescope and block out the light from a specific star, allowing the telescope to capture light directly from the much-less bright planet that is orbiting the star. That light can contain information about its size, orbital period, and even its atmospheric composition that would otherwise be lost in the overwhelming brightness of the planet’s star.

The shape of a starshade, which traditionally looks like a flower petal, might seem counterintuitive at first – if you’re trying to block a star’s light, why not just make the shape circular? But starlight coming from far away can diffract around a simple circle structure. The petals are explicitly designed to stop that from happening and completely block out even diffracted light around the shape’s edges.

Fraser interviews another Starshade expert – Dr. Markus Janson from Stockholm University

But it’s not the shape that makes it hard to deploy—it’s its size. Starshades are typically designed to be hundreds of meters across. Therefore, they are impossible to fit inside a traditional rocket fairing fully assembled. What’s more, they have to move along with the telescope—if the telescope the starshade is meant to accompany is pointed at another star and redirected, the starshade has to move with it.

The wrinkle is that the starshade is likely tens of thousands of kilometers from the telescope it is designed to assist. So, a slight change of a few degrees of inclination for the telescope would mean hundreds of thousands of kilometers of travel for its associated starshade. That kind of movement requires a lot of fuel, which is also costly due to the weight requirements of launching these objects so far away. 

No wonder a starshade has yet to be successfully deployed in space. Combining gigantic sizes that don’t fit inside rocket fairings and massive amounts of fuel to relocate every time the telescope needs to look at a different star are significant strikes against the concept. However, if humanity wants to directly image an exoplanet in the habitable zone of another star, there is still no better way to do so.

NASA animation of the deployment of a starshade

Enter Dr Gregg’s idea—she proposes using metamaterials for her starshade, which is robotically constructed in orbit. Metamaterials have several advantages over existing proposed starshades (one of which, by Nobel Prize winner John Mather, is another NIAC recipient this year). 

First, metamaterials are lighter. As with all things launched into space, being lighter means less cost – or, in this case, the ability to bring more fuel, allowing the starshade to operate longer than alternatives. 

Second, the specific kinds of metamaterials she proposes to use are much less likely to break. As she mentioned to Fraser in an interview, “The more stiffness a material has, the less damping it has. It’s just sort of a natural trade-off”. So, if a starshade is made from traditional materials, it would either be stiff and rigid but prone to vibrational strain when moving between positions or being deployed, or it would be very flexible but would have difficulty holding its shape when it’s supposed to.

This video shows phononic materials in action.
Credit – aiM Program at Duke University YouTube Channel

The metamaterial Dr. Gregg and her colleagues have proposed uses a type of material that both holds its structure well but also suppresses vibration by a unique use of a material called a phononic crystal. These were initially engineered to dissipate sound waves. This means that when used as a material in a starshade, it could dampen any feedback on the structure from things like micrometeoroid impacts, solar radiation, or even the process of deployment and assembly.

Using robots to deploy the starshade is another focal point of Dr. Gregg’s work, as she discusses with Fraser. Still, for this Phase I NIAC project, she is focusing on developing the model for starshade itself and selecting the appropriate material. As with all NIAC projects, she can apply for more funding in a Phase II round upon completion of her Phase I. If she receives it, humanity will be one step closer to seeing a giant floating petal in space – but one with very particular mechanical and structural properties.

Learn More:
NASA / C. Gregg – Dynamically Stable Large Space Structures via Architected Metamaterials
UT – In Order to Reveal Planets Around Another star, a Starshade Needs to Fly 40,000 km Away from a Telescope, Aligned Within Only 1 Meter
UT – Starshade Prepares To Image New Earths
UT – To Take the Best Direct Images of Exoplanets With Space Telescopes, we’re Going to Want Starshades

Lead Image:
Artist concept highlighting the novel approach proposed by the 2025 NIAC awarded selection of the Dynamically Stable Large Space Structures via Architected Metamaterials concept. NASA/Christine Gregg

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Star formation in the early Universe was a vigorous process that created gigantic stars. Called Population 3 stars, these giants were massive, extremely luminous stars, that lived short lives, many of which were ended when they exploded as primordial supernovae.

But even these early stars faced growth limitations.

Stellar feedback plays a role in modern star formation. As young stars grow, they emit powerful radiation that can disperse nearby gas they need to keep growing. This is called protostellar radiative feedback, and it takes place in addition to the restrictive effect their magnetic fields have on their growth.

However, new research shows that the growth of Pop 3 stars was limited by their magnetic fields.

The research is titled “Magnetic fields limit the mass of Population III stars even before the onset of protostellar radiation feedback.” The lead author is Piyush Sharda, an astrophysicist at the Leiden Observatory in the Netherlands. It’s available on the pre-print server arxiv.org.

Scientists observe stars forming in the modern Universe to understand how the process plays out. This is difficult because stars take so much time to form, while we’ve only been watching young stars from a great distance for a few decades. Stars are massive, energetic, complex objects that don’t give up their secrets easily.

There are many unanswered questions about star formation, but a general picture has emerged. It starts with a cloud of cold molecular hydrogen that collapses into dense cores. These cories become protostars, also called young stellar objects (YSOs). Accretion disks form around the young stars, and this is where radiative feedback comes in.

This artist’s concept shows a young stellar object and the whirling accretion disk surrounding it. NASA/JPL-Caltech

As young stars accrete mass, they heat up. They radiate this heat outward into their own accretion disks. As the material in the disk heats, it slows or even stops the accretion process. So radiative feedback limits their growth.

YSOs also rotate more rapidly than more mature stars. The rotation creates powerful magnetic fields, and these fields drive jets from the YSO’s poles. These jets steal away some of the accretion energy, limiting the stars’ growth. The jets can also disperse some of the surrounding gas, further limiting their growth.

However, the picture may look different for Pop 3 stars. To begin with, their existence is hypothetical at this point in time, though theory supports it. If they’re real, astrophysicists want to know how they formed and what their growth limits were. If they’re real, Pop 3 stars played a critical role in the Universe by forging the first metals and spreading them out into space.

According to the authors of the new research, simulations haven’t been thorough enough to explain the masses of Population 3 stars.

“The masses of Population III stars are largely unconstrained since no simulations exist that take all relevant primordial star formation physics into account,” the authors write. “We evolve the simulations until 5000 years post the formation of the first star.”

In the team’s more thorough simulations, which include magnetic fields and other factors, these early stars are limited to about 65 solar masses. “In 5000 yrs, the mass of the most massive star is 65 solar masses in the RMHD <radiation magnetohydrodynamics> simulation, compared to 120 solar masses in simulations without magnetic fields,” they write.

This figure from the research shows a panel from each type of simulation: HD (hydrodynamic), MHD (magneto-hydrodynamic), RHD (radiation-hydrodynamics including ionizing and dissociating radiation feedback), RMHD (radiation-magnetohydrodynamics). They show each simulation at 5,000 years after the first star forms. White dots show the positions of Population 3 stars. Image Credit: Sharda et al. 2025

The results show that both simulation runs that included magnetic fields are fragmented, leading to the formation of Pop 3 star clusters. That means that the evolution of the most massive Pop 3 stars in both runs is influenced by the presence of companion stars.

The difference comes down to gravity and magnetic fields working against each other. As young stars accrete mass, their gravitational power increases. This should draw more material into the star. But magnetic fields counteract the gravity. This all happens before radiative feedback is active.

The results also show that in both simulations that include magnetic fields, the amount of mass that reaches the envelope initially increases, then declines. However, the results were different in the simulations without magnetic fields. In those simulations, mass transfer from the envelope to the accretion disk is fast at first, creating a decline in the mass in the envelope and a build-up of mass in the disk. “This mass is consequently accreted by the star at a high rate,” the authors write.

This figure from the research illustrates some of the simulation results. It shows the mass enclosed within a disk of radius 500 au and height 50 au (from the midplane) around the most massive star. “The mass reservoir that can be accreted onto the central star in the MHD and RMHD runs eventually decreases as magnetic fields suppress gravitational collapse,” the authors explain.

“We learn that magnetic fields limit the amount of gas infalling onto the envelope at later stages by acting against gravity, leading to mass depletion within the accretion disk,” the authors explain. “The maximum stellar mass of Population III stars is thus already limited by magnetic fields, even before accretion rates drop to allow significant protostellar radiative feedback.”

Though Population 3 stars are only hypothetical, our theories of physical cosmology rely on their existence. If they didn’t exist, then there’s something fundamental about the Universe that is beyond our grasp. However, our cosmological theories do a good job of explaining what we see around us in the Universe today. If we’re putting money on it, place your bets on Pop 3 stars being real.

“Radiation feedback has long been proposed as the primary mechanism that halts the growth of Pop III stars and sets the upper mass cutoff of the Pop III IMF (initial mass function),” the authors write in their conclusion. They show that magnetic fields can limit stellar growth before feedback mechanisms come into play.

“This work lays the first step in building a full physics-informed mass function of Population III stars,” the authors conclude.

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The structure of the cosmos is rooted in symmetry. As first demonstrated by Emmy Noether in 1918, for every physical law of conservation in the Universe, there is a corresponding physical symmetry. For example, all other things being equal, a baseball hit by a bat today will behave exactly the same as it did yesterday. This symmetry of time means that energy is conserved. Empty space is the same everywhere and in all directions. This symmetry of space means that there is conservation of linear and rotational momentum. On and on. This deep connection is now known as Noether’s Theorem, and it is central to all of modern physics.

Where Noether’s Theorem really shows its power is in particle physics. Although the mathematics of particle physics is complex, the underlying symmetries govern what can happen when particles collide. So, conservation of charge means that when a particle collision creates a shower of new particles, the total charge of all the particles must equal the total charge of the particles before the collision. Another basic symmetry is parity, also known as mirror symmetry. If you stand in front of a mirror and raise your right hand, your mirror image will raise its left. If you spin a ball toward your left, the mirror ball will spin to the right. Since elementary particles have an inherent rotation or spin, this means that particle showers should appear in rotational pairs.

One way to test the laws of physics is to see where certain symmetries are broken. In particle physics, an important symmetry is the combination of charge and parity, known as charge-parity, or CP symmetry. CP symmetry is what requires that for every matter particle, there must be a corresponding antimatter particle. For a long time, it was thought that CP symmetry was conserved, which was a problem for cosmologists since our Universe is made almost entirely of matter, not a mix of matter and antimatter. But in the last half of the 20th century, we found examples of CP violations, which led to a revolution in our understanding of the standard model of particle physics.

Examples of symmetry in physics. Credit: Flip Tanedo

Although it isn’t mentioned as much, the same symmetries apply to general relativity. In fact, Einstein’s equations can be derived by applying the physical symmetries seen in Newtonian physics while dropping the requirement that space be Euclidean. Technically, the principle of equivalence Einstein used to derive relativity is a consequence of symmetries, not the other way around. So what if we used these symmetries to test relativity the way we do in particle physics? One way to do this would be to look at the mergers of black holes, which is the point of a recent study in Physical Review Letters.

In this work, the team looked at the gravitational waves generated by the mergers of stellar black holes. Specifically, they focused on the polarization of the gravitational waves. Since gravitational wave polarization is connected to the rotation of the merging black holes, this allowed the team to test parity conservation. Under the standard model of general relativity, parity should be conserved, and this is precisely what the team found. To the limits of observation, black holes don’t violate parity. That said, we should note that the observational limit is pretty weak. We simply haven’t observed enough mergers to conclusively prove black holes obey parity, though we expect that they do.

Symmetry in black hole collisions. Credit: Calderón Bustillo, et al

The team also looked at the recoil effect of black holes in a second paper. When two black holes merge, the resulting black hole can get a gravitational kick that sends it flying off from its point of origin. If spatial symmetry holds, then the recoil of black holes shouldn’t show any bias, such as having more of them speed away from us than toward us. Again, the team saw no violation of symmetry, in agreement with general relativity.

Neither of these results are strong enough to be conclusive, and since both results are what we expect, there’s nothing surprising in this work. But studies such as this are worth doing as we continue to gather data. We know that somehow general relativity and quantum theory must combine into a general theory of quantum gravity, and we know that quantum theory violates some of the symmetries of general relativity. A big question is whether quantum gravity violates any symmetry as well. In time, studies such as these could give us the answer.

Reference: Calderón Bustillo, Juan, et al. “Testing mirror symmetry in the Universe with LIGO-Virgo black-hole mergers.” Physical Review Letters 134.3 (2025): 031402.

Reference: Leong, Samson HW, et al. “Gravitational-wave signatures of mirror (a) symmetry in binary black hole mergers: measurability and correlation to gravitational-wave recoil.” arXiv preprint arXiv:2501.11663 (2025).

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One of my gripes with ‘The Martian’ movie was the depiction of the winds on Mars. The lower air density means that the sort of high speed winds we might experience on Earth carry far less of an impact on Mars. During its 72 flights in the Martian air, NASA’s ingenuity helicopter took meticulous records of the conditions. A new paper has been released and reports upon the wind speeds on the red planet at various altitudes. Previous models suggested wind speeds would not exceed 15 m/s but Ingeniuty saw speeds as high as 25 m/s.

Of all the planets in our Solar System, Mars is perhaps the most similar to Earth, similar but with stark differences. The weather on Mars is harsh and extreme, characterised by cold temperatures, a rarefied atmosphere and dust storms. The average temperature is around -60°C but it can reach a toasty 20°C in summer near the equator. It’s atmosphere is composed mostly of carbon dioxide and is about 100 times thinner than Earth’s so it offers little insulation or protection from solar radiation. On occasion, the winds on Mars whip up global dust storms that obscures the planet’s surface from view. 

Mars seen before, left, and during, right, a global dust storm in 2001. Credit: NASA/JPL/MSSS

Our model of the Martian atmosphere was believed to be fairly accurate, that is until Ingenuity arrived and completed more than 70 successful flights. As part of the Mars 2020 mission and the first aerial vehicle to successfully complete powered flight on another world, Ingenuity revealed some surprising conditions. Surprisingly too perhaps, the first attempt at powered flight was supposed to be a technology demonstration but instead, it provided high resolution images to help direct the ground based rover and collected data from the atmosphere and became a key part of Mars 2020. 

The Ingenuity helicopter photographed by the Perseverance rover. Credit: NASA/JPL-Caltech

One of the outcomes from Ingenuity’s flights was a better understanding of Martian winds. In a paper written by Brian Jackson and team in the Planetary Society Journal, the team explained their rather ingenious approach. Knowing that the payload was severely limited on board, the decision was taken to use Ingenuity itself to confirm windspeeds. Previous studies had shown that the tilt of a stably hovering drone can be used to calculate speeds. Drones produce forward thrust by tilting in the direction they need to move, if they are stable and in a hover yet the wind is blowing, the drone will drift. Instead and to counteract the drift, the drone tilts flying into wind to maintain position relative to the ground, tilting more in a stronger headwind. 

Measuring the tilt is relatively straightforward thanks to a collection of engineering sensors, cameras and accelerometers. With all of the information gathered by these onboard pieces of equipment and returned to Earth, the analysis and calculation of the drone at different altitudes has enabled the wind speeds to be accurately calculated.

Part of the Ingenuity rotorcraft

The results were a surprise, showing that the winds on Mars were generally higher than anticipated. Speeds were measured at altitudes from 3 to 24 metres and were found to be blowing at anything up to 25 m/s. This perhaps is a result of Ingenuity’s unique capability of being able to measure speeds at different altitudes over a period of time. Previous measurements have been achieved from probes as they have descent through the atmosphere or from probes on the ground. Taking the success of Ingenuity forward, mission specialists working upon the Dragonfly rotorcraft that will be visiting Titan hope to be able to replicate the results and gain a better understanding of its wind profile too. 

Source : Profiling Near-surface Winds on Mars Using Attitude Data from Mars 2020 Ingenuity

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Fast Radio Bursts (FRBs) are one of the greater mysteries facing astronomers today, rivaled only by Gravitational Waves (GWs) and Gamma-ray Bursts (GRBs). Originally discovered in 2007 by American astronomer Duncan Lorimer (for whom the “Lorimer Burst“ is named), these shot, intense blasts of radio energy produce more power in a millisecond than the Sun generates in a month. In most cases, FRBs are one-off events that brightly flash and are never heard from again. But in some cases, astronomers have detected FRBs that were repeating in nature, raising more questions about what causes them.

Prior to the discovery of FRBs, the most powerful bursts observed in the Milky Way were produced by neutron stars, which are visible from up to 100,000 light-years away. However, according to new research led by the Netherlands Institute for Radio Astronomy (ASTRON), a newly detected FRB was a billion times more radiant than anything produced by a neutron star. What’s more, this burst was so bright that astronomers could see it from a galaxy one billion light-years from Earth! This finding raises innumerable questions about the kinds of energetic phenomena in the Universe.

The research was led by Inés Pastor-Marazuela, a Rubicon Research Fellow at the Jodrell Bank Centre for Astrophysics and a researcher with ASTRON and the Anton Pannekoek Institute, University of Amsterdam. She was joined by multiple colleagues from ASTRON, the Cahill Center for Astronomy, the National Centre for Radio Astrophysics, the Netherlands eScience Center, the Perimeter Institute for Theoretical Physics, and the Department of Space, Earth and Environment at Chalmers University of Technology. The paper detailing their findings recently appeared in Astronomy & Astrophysics.

The discovery was made using the Westerbork Synthesis Radio Telescope (WSRT) – part of the European VLBI network (EVN) – a powerful radio telescope consisting of 14 steerable 25 m (ft) dish antennas. This observatory relies on a technique called “aperture synthesis” to generate radio images of the sky, enabling astronomers to study a wide range of astrophysical phenomena. After more than two years of observation, the WSRT’s sophisticated instruments and techniques led to the discovery of 24 new FRBs.

These discoveries were made with the help of an experimental supercomputer, the Apertif Radio Transient System (ARTS), specifically designed to study FRBs. This supercomputer analyzed all the radio signals coming from the sky during the observation period, which helped the team deduce where future FRBs would appear. As Pastor-Marazuela said in an ASTRON press release:

“We were able to study these bursts in an incredible level of detail. We find that their shape is very similar to what we see in young neutron stars. The way the radio flashes were produced, and then modified as they traveled through space over billions of years, also agrees with a neutron star origin, making the conclusion even stronger”.

Essentially, the team taught ARTS to look specifically for bursts that are very short, very bright, and from very distant sources. Radio sources that meet all three criteria will likely be the most powerful and fascinating. When ARTS finds such bursts in the data, it autonomously zooms in on the phenomena and informs the astronomers. Said research leader Joeri van Leeuwen from ASTRON:

“We generally do not know when or where the next FRB will appear, so we have a vast computer constantly crunch through all radio signals from the sky. After a while, the resemblance with the flashes we know from highly magnetic neutron stars started to emerge, and we were very excited that we lifted part of the veil around these perplexing bursts. We were just starting to think we were getting close to understanding how regular neutron stars can shine so exceedingly bright in radio. But then the Universe comes along and makes the puzzle one billion times harder. That’s just great”.

While this new mystery is intriguing, the team is also excited that they have been able to link FRBs to young neutron stars for the first time. “It is amazing to work on these distant FRBs, [you] really feel you are studying them up close from a single burst, and find they appear to be neutron stars,” said Pastor-Marazuela.

Further Reading: ASTRON, Astronomy & Astrophysics

The post Fast Radio Bursts Appear to Be Caused by Young Neutron Stars appeared first on Universe Today.

When searching for alien life, it’s not unusual to use Earth as a test bed for theories and even practice runs. Perhaps one of the most tantalising places in the Solar System to look for life is Saturn’s moon Enceladus. It has a liquid water interior and it is here that life may just be possible. A team of researchers want to test techniques for searching for life on Enceledaus by exploring the oceans of Earth. They have collected  water and ice samples and hope to find chemicals like methane and hydrogen. 

The search for alien life is one of that has fascinated humanity for decades. Scientists explore this vast question through various avenues, including the study of exoplanets within the habitable zones of distant stars but there is still hope that maybe, just maybe we will find life elsewhere in our own Solar System. Some of the moon’s of the outer planets offer tantalising possibilities such as Enceladus, a moon of Saturn. It’s an icy moon where, beneath the icy crust, there is the possibility of the global ocean of liquid water teeming with life.

Saturn’s moon Enceladus isn’t just bright and beautiful. It has an ocean under all that ice that could have hydrothermal vents that create organic chemicals. Image Credit: NASA, ESA, JPL, SSI, Cassini Imaging Team

When the Cassini-Huygens probe visited Saturn in 2004 it sampled the cryogenic plumes that had been ejected over the southern pole, Using its Ion and Neutral Mass Spectrometer and Cosmic Dust Analyser, research teams identified the presence of water ice, methane and other carbon based molecules. Molecular hydrogen, molecular nitrogen and other elements all of which suggest the sub-surface ocean was a salty composition with the necessary elements for primative life. However to date, no evidence has been found. 

Artist impression of Cassini Space Probe

It’s thought that the ice crust of Enceladus is anything form a few kilometres to up to 40 km thick. Beneath, and in the depths of the ocean are thought to be hydrothermal vents  which, just like oceans on Earth, are a source of energy that could drive entire ecosystems. With all the ingredients for life, missions have been discussed to explore the astrobiological aspects of Enceladus. Mission with mass spectrometers have been proposed to identify biosignatures within the ocean. 

In the paper published in Planetary and Space Science and written by a team led by F. French from the Università degli Studi di Bari in Italy, the team look at the technical possibility of detecting methane cycling on Enceladus. If it can be observed, then it would give a strong indication that the sub-surface ocean is currently, or has been habitable in the past. The conclusion can be quite reliably drawn since the methane cycle on Earth is often the result of biological and abiotic processes but is generally considered a byproduct of microbial activity. 

NASA and ESA have been discussing possible missions to Enceladus but ahead of that, one way of practicing the ability to detect geochemical signatures of life is to see if it can be detected on Earth using the same technology. The Arctic Ocean is a great analogy to the conditions on Enceladus with vents on the sea floor in an ocean covered with ice for the majority of the year. The team conducted experiments to simulate the processes and techniques future missions are likely to employ on Enceladus and other outer moons. 

The team found that they were able to detect and measure emitted concentrations of carbon dioxide, other carbon isotopies and other oxygen isotopes within the water. Their results suggest it will be possible to detect the necessary elements using a mass spectrometer at Enceladus. Further studies are appropriate to refine the processes ahead of a future mission. 

Source : An Arctic Analogue for the Future Exploration of Possible Biosignatures on Enceladus

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In April 2026, NASA will launch a crew of four as part of the Artemis II mission, a circumlunar flight that will last 10 days. This mission will set the stage for Artemis III, the long-awaited return to the Moon, currently scheduled for mid-2027. With the deployment of the Lunar Gateway (also scheduled for 2027), NASA intends to conduct regular missions to the Moon (once a year). With the help of international and commercial partners, NASA then hopes to build a lunar base and the related infrastructure that will allow for a “sustained program of lunar exploration and development.”

However, the current schedule is the result of multiple delays, budget restrictions, and issues with the various mission elements. Given the uncertain nature of politics in the U.S. right now, there are concerns that further delays may be inevitable. Meanwhile, China and its partners continue to push ahead with their plans to create a base in the South Pole-Aitken Basin – the International Lunar Research Station (ILRS) – that will rival NASA’s Artemis Program. Understandably, this situation has raised concerns about who will send crewed missions to the Moon and establish a base there first.

Back to the Moon to Stay!

For NASA, the long-awaited return to the Moon began two decades ago with the passage of the NASA Authorization Act of 2005. In addition to allocating funds for robotic space exploration and Earth Observation programs, the Act also instructed the agency to “establish a program to develop a sustained human presence on the Moon, including a robust precursor program, to promote exploration, science, commerce, and United States preeminence in space, and as a stepping-stone to future exploration of Mars and other destinations.”

Artist’s impression of the Ares I and V rockets. Credit: NASA/MSFC

This led to the creation of the Constellation Program, which would see astronauts return to the Moon for the first time since the Apollo 17 mission in 1972. Since then, NASA’s plans have evolved due to unforeseen circumstances like the Great Recession (2007-2009) and budget shortfalls. By 2010, NASA came back with a new plan known as the Moon to Mars mission architecture, which called for the development of the next-generation Space Launch System (SLS) and the Orion spacecraft.

By 2017, the Artemis Program was inaugurated with the long-term goal of creating a “sustained program of lunar exploration and development.” This plan currently includes returning astronauts to the lunar surface by 2028, followed by the creation of a permanent base around the lunar south pole. Since then, they have enlisted the help of several space agencies and national governments through the Artemis Accords and multiple commercial partners through the Commercial Lunar Payload Services (CLPS) and Human Landing System (HLS) programs to realize this goal.

However, in 2021, China and Roscosmos declared a joint plan to establish their own permanent base in the Moon’s south pole region, the International Lunar Research Station (ILRS). The program’s timetable calls for Russian cosmonauts and Chinese taikonauts to land on the Moon for the first time by 2030. In 2023, China announced this would consist of two Long March 10 rockets launching the Mengzhou spacecraft and the Lanyue lunar lander, the former carrying two taikonauts and the latter ferrying them to the surface and back.

The Gateway & Base Camp

In 2012, NASA proposed a cislunar station to facilitate its “Moon to Mars” mission architecture, dubbed the Deep Space Habitat. By 2018, the design and the program had matured considerably and was renamed Lunar Gateway. This station is now a multinational collaborative project between NASA, the European Space Agency (ESA), the Japan Aerospace Exploration Agency (JAXA), the Canadian Space Agency (CSA), and the UAE’s Mohammed Bin Rashid Space Centre (MBRSC).

According to the current design, this station will consist of the “core elements”: the Power and Propulsion Element (PPE) and the Habitation and Logistics Outpost (HALO), which will launch no sooner than 2027. Further modules will include the European System Providing Refueling, Infrastructure and Telecommunications (ESPRIT), the Lunar International Habitation Module (Lunar I-HAB Module), the Canadarm3 robotic manipulator arms, and the Crew and Science Airlock Module.

By 2020, the surface elements of the Artemis Program, known as the Artemis Base Camp, were announced. This camp was described in detail as part of NASA’s Lunar Surface Sustainability Concept. The plan includes three core elements that would enable a sustained lunar presence, emphasizing mobility and the ability to conduct extensive science operations.

• A Lunar Terrain Vehicle (LTV) that will transport crewmembers around the landing zone
• A pressurized Habitable Mobility Platform (HMP) that will allow crews to take trips across the lunar surface for up to 45 days
• A lunar Foundation Surface Habitat (FSH) that will house as many as four crew members on shorter surface stays

The Space Launch System (SLS) and the Orion spacecraft are vital to this program, which NASA has been developing since 2011. In 2018, then-Administrator Jim Bridenstine and VP Mike Pence directed NASA to expedite the timetable so astronauts would land on the Moon by 2024. This created a problem since the Lunar Gateway would not be ready in time, leading to the Human Landing Systems (HLS) contract. The resulting concepts include the Starship HLS developed by SpaceX and the Blue Moon Mk. 2 developed by Blue Origin.

The ILRS

In June 2021, the China National Space Agency (CNSA) announced they had partnered with the Russian State Space Corporation (Roscosmos). The detailed plan was made public with the release of the International Lunar Research Station (ILRS) Guide for Partnership, which explained how international partners could join. According to the design, five facilities will make up the ILRS. They include:

• Cislunar Transportation Facility (CLF): An orbital station that mirrors the purpose of the Lunar Gateway.
• Telemetry, Tracking, and Command (TT&C): An energy supply network, a thermal management system, and support modules.
• Lunar Transportation and Operation Facility (LTOF): A storage facility where lunar vehicles will be stowed and maintained when not in use.
• Lunar Scientific Facility: A support lunar science operations on the surface, in-orbit, or in deep space.
• Ground Support and Application Facility (GSAF): An operational support facility for communications and missions and a data center for lunar and deep-space missions.

The timeline for the base’s construction is divided into three phases. Phase I—Reconnaissance, which began in 2021 and will last until the end of 2025, consists of exploring the South Pole-Aitken Basin and sample return missions by the Chang’e missions to scout for potential ILRS sites and verify technologies that will allow for soft landings in the southern polar region. This phase has involved multiple launches using China’s Long March 3B (CZ-3B) and Long March 5 (CZ-5), and the Russian Soyuz-2 rocket.

Visualization of the ILRS from the CNSA Guide to Partnership (June 2021). Credit: CNSA

Phase II—Construction is planned to last from 2025 to 2030. The goals of this phase include verifying technologies related to the ILRS command center, analyzing the Chang’e samples to narrow the selection of potential sites, and delivering cargo to build the base. Other objectives will include technologies related to ISRU, 3D printing, and others necessary for the construction of the ILRS. For Phase II and III, China and Russia would begin relying on the Long March 9, Long March 10, and the Angara 5M heavy launch vehicles.

Phase III – Utilization, which will run from 2030 to 2035, will involve the completion of all in-orbit and surface facilities that provide energy, communication, research, exploration, and transport services. This phase will consist of five IRLS missions to establish the base architecture:

• IRLS-1 – establishment of the command center, basic energy, and telecommunications facilities.
• IRLS-2 – establishment of lunar research exploration facilities (sample collection, lunar physics, geology, lava tubes).
• IRLS-3 – establishment of lunar ISRU technology verification facilities.
• IRLS-4 – verification of general technologies like biomedical experiments, sample collection, and return.
• IRLS-5 – establishment of lunar-based astronomy and Earth observation facilities.

Issues and Delays

Long before the Artemis Program was first announced, NASA was experiencing significant delays with the development of mission-critical elements. This includes the SLS, which began development in 2011 with a government-mandated launch set for late 2016. However, cost overruns, management issues, and other challenges delayed this for nearly six years. This also caused delays in the development of the Orion spacecraft, which performed its first successful test flight on December 5th, 2014. The next flight, Artemis I, did not occur until almost eight years later.

On November 16th, 2022, the SLS launched for the first time, sending the Artemis I spacecraft (without crew) on a circumlunar flight. This was to be followed by Artemis II, a crewed circumlunar flight, in 2023 and Artemis III in 2024. In November 2021, due to legal challenges over the HLS contract, NASA declared that Artemis III‘s launch date would be pushed until 2025. On January 2024, NASA Administrator Bill Nelson announced that Artemis II and III would launch no sooner than September 2025 and 2026.

However, by the end of the year, Nelson announced that these missions would be delayed due to the months of engineering investigations into issues with the life support system and heat shield, but should occur no later than April 2026 and mid-2027. There have also been delays on SpaceX’s end. While the company has made several impressive strides with the launch and recovery of the Starship, the first successful orbital test flight took place on June 6th, 2024 – a year after its first crewed launch was scheduled to take place (the dearMoon project) and the same year it was to assist the Artemis III mission.

The complex architecture for that mission also involves orbital refueling, which SpaceX anticipates hopes to test sometime this year. However, concerns have been raised about the number of refuelings needed to allow the Starship to make a Trans-Lunar Injection (TLI) maneuver. At present, the Artemis III and IV missions will involve a Starship HLS docking with a refueling facility in orbit before making a TLI. This facility will be serviced by multiple Starship propellant tankers, but estimates vary on how many launches will be needed to refuel the HLS fully.

Whereas Musk has previously stated that it could be between 4 and 8, others estimate that 16 launches will be needed to fuel a single Starship HLS. SpaceX also hopes to conduct 25 launches with the Starship in 2025, including an orbital refueling followed by an uncrewed TLI and lunar landing in preparation for Artemis III. However, due to the recent loss of a Starship during the most recent flight (January 16th, 2025) and the resulting FAA penalties, these missions may not occur before the year’s end.

Keith Cowing, an astrobiologist and former rocket scientist, is currently the editor of the publications NASA Watch and Astrobiology. As he summarized to Universe Today via messenger:

“The main problem with Artemis as a whole has been poor cost projections, inadequate cost monitoring, bad contract oversight, and over-optimistic schedules that are driven by the need to look like you are making good progress. Any one of these can cause cost overruns and schedule delays. When you have all of them happening, you can have substantial problems.

“The main problems have had to do with the ground infrastructure for launch, issues with the Orion spacecraft, and the impact of earlier cost saving attempts. The most unusual of which was a decision to re-use the avionics from Artemis II Orion in the Artemis III Orion instead of simply building one set of avionics for each. It takes a lot of time to remove things, re-install them, and re-certify them for flight.”

Orion is NASA’s deep space exploration spaceship that will carry astronauts from Earth to the Moon and bring them safely home. Credit: Lockheed Martin Is Roscomos Out?

However, Roscosmos has also suffered serious setbacks due to Russia’s invasion of Ukraine in February 2022. This includes Roscosmos terminating its involvement in the International Space Station (ISS) and the European Space Agency (ESA) suspending cooperation with Roscosmos for the ExoMars rover mission. Roscosmos has also seen a significant drop in revenue since 2022, reporting financial losses of 180 billion rubles ($2.1 billion) in February 2024 due to canceled contracts.

In addition, Roscosmos has experienced a significant drop in launches per year, a trend that began with the annexation of Crimea in 2014. This includes missions related to the ILRS, like the Luna-25 mission. After a two-year delay, the mission was lost when it crashed on the lunar surface in August 2023. This mission and the subsequent launch of Luna-26 and Luna-27, originally scheduled for 2024 and August 2025 (respectively), were a key part of Phase I of the IRLS’ development.

Since the loss of Luna-25, these missions have been delayed until 2027 and 2028. The Luna-28 mission, meant to play an important role in Phase II of the ILRS’ development, has also been pushed back to 2030. In addition, these three missions, and several payload deliveries in Phase II and III are dependent on Russia’s Angara A5 rocket. The design of this heavy-lift rocket was formalized in 2004, and the first test flight occurred in December 2014, but the next flight did not occur for another six years (December 2020).

The third followed in December 2021, which failed to deliver its payload to the intended orbit. The Angara 5M, unveiled in 2017 to address problems with earlier models, made its maiden flight in April 2024. While multiple launches are scheduled between 2025 and 2030s, none are associated with the Luna program or the ILRS. Said Cowing:

“Russia is cash-strapped and is still isolated from most of the world’s economic systems. In addition, their space sector was already suffering from draconian budget cuts, over-promising things that never happened, and increasingly shoddy workmanship from their contractors. The manufacturing problems with a Soyuz capsule and the malfunction of thrusters in the Nauka module, plus the aging of their part of the ISS, simply serve to exacerbate these challenges further.

The first Long March 5 rocket being rolled out for launch at Wenchang in late October 2016. Credit: Su Dong/China Daily

Despite these setbacks, China continues to pursue the ILRS and there is little doubt that China will be able to continue without Russian involvement. The success of the Chang’e program to date and their progress with the Long March 9 (CZ-9) is certainly an indication of that.

“China, on the other hand, has a rather robust human spaceflight program of its own, including a large space station,” added Cowing. “They also have an ambitious lunar program that has chalked off one success after another. And their robotic and space station programs are all focused on methodically developing the ability to send their astronauts to the Moon. They really do not need the Russians, and the Russians cannot afford to do much anyway.”

Conclusions?

As it stands, China plans to send the first taikonauts to the Moon in 2030, and they appear to be on track to achieve that. This includes the first launch of the Long March 10, slated for 2026, and the successful test of the Mengzhou spacecraft in 2020. In April 2024, the China Manned Space Agency (CMSA) announced that the initial development of the Lanyue lander was complete. This was followed by an announcement in October that a separation test for the lander and its propulsion stage had been carried out. However, unforeseen delays may occur that could cause the target date to be pushed.

Meanwhile, NASA has experienced multiple delays and there are still logistical questions that need to be worked out with the Starship HLS. However, NASA and its commercial partners still have the lead regarding the major mission elements. For instance, they have already built and validated the SLS and Orion spacecraft, while SpaceX has successfully completed multiple orbital flights with the Starship. While the target date of mid-2027 may slip further, they could still make their original (pre-Artemis) target date of 2028.

What’s more, NASA has the benefit of experience, having already sent six missions and 12 astronauts to the Moon. In addition, NASA has launched over 1,000 uncrewed and 250 crewed missions into Earth orbit or beyond since its inception in 1958, plus thousands more through its commercial programs. As of January 23rd, 2025, China has conducted 558 launches using the Long March family of rockets and trails the U.S. significantly in terms of annual launches. As the saying goes, “There’s no substitute for experience.”

So… will China send its first taikonauts to the Moon before NASA can make its long-awaited return? In Cowing’s estimation, the chance of that happening is “doubtful.” However, there is little doubt that their robust space program will be a force to be reckoned with in the coming decades, be it in orbit, on the Moon, and (in all likelihood) on Mars!

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Ever since Isaac Newton famously talked about gravity, its dominance as a force in our Solar System has been well known. It’s responsible for the orbits of the planets and their satellites but there are other forces that have shaped our planetary neighbourhood. A new paper has been released where an astronomer discusses how recoiling ice from comets can push them around and how the radiation pressure from the Sun drives material outwards. There are also relativistic effects too that can cause particles to spiral inward toward the Sun. 

Gravity is the force that governs the structure and motion of the solar system, keeping celestial bodies together in a cosmic dance. The Sun, with its immense mass, generates the strongest gravitational pull, anchoring planets, asteroids, comets, and other objects in orbit around it. Each planet’s orbit results from the balance between its velocity and the Sun’s gravitational force, creating elliptical paths described by Kepler’s laws of motion. Similarly, moons remain in orbit around their host planets due to the gravitational forces exerted by their parent planet. Gravity not only maintains the stability of these orbits but also influences phenomena like tides on Earth, caused by the Moon’s gravitational pull.

View of Moon limb with Earth on the horizon,Mare Smythii Region. Earth rise. This image was taken before separation of the LM and the Command Module during Apollo 11 Mission. Original film magazine was labeled V. Film Type: S0-368 Color taken with a 250mm lens. Approximate photo scale 1:1,300,000. Principal Point Latitude was 3 North by Longitude 85 East. Foward overlap is 90%. Sun angle is High. Approximate Tilt minimum is 65 degrees,maximum is 69. Tilt direction is West (W).

In the paper authored by David Jewitt from the University of California he explores other forces that shape our Solar System. Gravity certainly describes the motion of planetary mass bodies but there are other forces that impart forces upon smaller bodies that are susceptible to their effects. These forces include, but are not limited to recoil (as per Newton’s third law of motion that every action has an equal and opposite reaction,) torque from mass loss, radiation pressure and more. 

The aim of the paper is to offer a simple yet informative overview of the various non-gravitational forces at play in the Solar System. There are references to relevant applications from existing papers and publications, presenting them in a way that is accessible to non-specialists. An important point to note is that the paper assumes that all orbits are circular, whereas real bodies are not perfectly spherical and orbits are not perfectly circular. The author asserts that these approximations ensure that rough estimates of the magnitudes of forces can still be achieved. 

Among the non-gravitational forces considered in the paper, the largest by far is the recoil produced by the sublimation of ice on comets and asteroids. The heat from the Sun causes the ice to immediately turn into a gas rather than melt to a liquid, this is the sublimation process. Like a bullet leaving a gun however, and in accordance with Newton’s laws, when the ice sublimates, the escaping volatile gasses will carry momentum and exert a recoil force on the body. The process of sublimation depends largely on temperature and acts in the anti-solar direction. 

Comet image from Hubble

Related to the appearance of comets is another force, radiation pressure, that shapes their distinctive tails. It’s the force exerted by light when photons transfer momentum to an object such as cometary dust and gas pushing them away. The pressure depends on the intensity of the radiation and the object’s reflectivity, with more reflective objects experiencing greater force. Though small, radiation pressure can shape comet tails and gradually alter the orbits of small bodies in the solar system.

The Sun releases a steady stream of charged particles called the Solar Wind. When it strikes unprotected surfaces like asteroids or the Moon, it can change the chemistry and even create water molecules. Image Credit: NASA’s Goddard Space Flight Center/Mary Pat Hrybyk-Keith

Source : Non-gravitational Forces in Planetary Systems

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Don’t know about you but when I think of Earth my mind is filled with the diversity of life and the rich flora and fauna. In reality, about 99% of Earth is uninhabitable; deep underground places with high pressure and temperature where even the toughest bacteria cannot survive. There are places though where life thrives from tiniest toughest bacteria to the largest elephant. Then there are places that are habitable but devoid of life; lava flows are a great example and the space between microbes. A paper recently released looks at these uninhabited, habitable areas and wonders what we may learn as we search for life in the Universe.

Life on Earth has taken millions of years to evolve to the state we see today and has invaded nearly every corner of the planet. That is, except those places where the environment is so extreme that even the toughest extremophile cannot survive. These regions include places like the Atacama Desert in Chile, one of the driest places on Earth, where rainfall is so rare that even microbial life struggles to survive. Similarly, parts of Antarctica’s dry valleys feature subzero temperatures, minimal liquid water, and high salinity in some soils, creating an environment hostile to most life forms. It raises interesting questions and perhaps pose limitations on life’s ability to survive. 

The rocks seen here along the shoreline of Lake Salda in Turkey were formed over time by microbes that trap minerals and sediments in the water. These so-called microbialites were once a major form of life on Earth and provide some of the oldest known fossilized records of life on our planet. NASA’s Mars 2020 Perseverance mission will search for signs of ancient life on the Martian surface. Studying these microbial fossils on Earth has helped scientists prepare for the mission. Image Credit: NASA/JPL-Caltech

We can learn a lot from life on Earth as we hunt for live elsewhere in the Universe. At the moment, there is just one place in the cosmos where we know life has evolved, that’s on Earth. A paper recently authored by Charles S Cockell from the University of Edinburgh explores what we might learn from the inhospitable places on Earth and how that might inform our search for extraterrestrial life. The paper discusses places where active microorganisms cannot be found in particular those places where the physical and chemical conditions are not far from areas that support life. 

The physical spaces where microbes cannot sustain the essential metabolic activity or even reproduce can be categorised into two groups: those with uninhabitable conditions and those with habitable but uninhabited spaces, also known as uninhabited habitats. You might need to read that a few times but it does make sense! Uninhabitable conditions occur in environments where life cannot exist due to extreme factors like intense heat, cold, salinity, or acidity. In contrast, uninhabited habitats are environments that are theoretically capable of supporting life but remain unoccupied, often due to barriers to colonisation or the absence of necessary organisms. The paper draws a strong differentiation between these ‘vacant niches.’

Lava cooling after an eruption. This rock has an entrained magnetic field fingerprint from the time it formed. Credit: kalapanaculturaltours.com

These uninhabited habitats, which form on both macroscopic and microscopic scales through diverse processes, offer opportunities for scientific investigation. They can act as negative control environments, helping to reveal how living organisms influence geochemical processes, and how they can provide a framework for studying processes like microbial succession and community development. Despite their potential significance, the occurrence of these habitats in environments at the physical and chemical extremes of life remain poorly understood.

As we continue our search for life across the universe, we may find many more locations like these. Doing so will help to expand our understanding of the distribution of habitable conditions and the potential for life across the universe. They may offer insights into the processes that make a location suitable for life, as well as the factors that have prevented life from arising or persisting there.

Source : Where the microbes aren’t

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The Einstein Probe was launched in January 2024 to look at X-ray transients, among other things. Its power comes from its Wide-field X-ray Telescope (WXT), which can capture 3600 square degrees of the sky in a single go. That’s an area 18,000 times the apparent area of the Moon. That is a huge patch of astronomical sky, so it’s not surprising that just two months later the probe saw a 17-minute burst of soft X-rays. Given the name EP240315a, it is an example of a fast X-ray transient (FXRT).

Because the WXT can pinpoint transients so quickly, other telescopes could make follow-up observations in real time. Within an hour after its first detection, the Asteroid Terrestrial-Impact Last Alert System (ATLAS) captured the event in visible light. Other observations from the Gemini-North telescope in Hawaii and the Very Large Telescope in Chile were able to measure the redshift of the event. They found that the light of EP240315a traveled for 12.5 billion years to reach us. Radio light from the event was captured from the Australian Telescope Compact Array (ATCA). A global team of observatories allowed astronomers to discover something interesting.

To begin with, radio observations of EP240315a were consistent with a gamma-ray burst (GRB). We often see a burst of X-rays before a GRB, but the X-rays usually appear just a few dozen seconds before the gamma rays. But in this case, the X-rays appeared six minutes before the GRB. This suggests that these GRBs occur through a process we don’t understand. The only way to be sure is to gather more data, which is where the Einstein Probe will come in.

One of the reasons we haven’t seen these kinds of early soft X-rays before a GRB is that they are rather faint. The X-ray light dims and fades as it travels billions of light-years, so it takes a sensitive detector such as the Einstein Probe to see them well. Given the rate at which gamma-ray bursts occur and the wide-field observations of the WXT, we should be able to see many more of them in the near future. Combined with the global team of other observatories, our understanding of GRBs may be set to change in the near future.

Reference: Ricci, Roberto, et al. “Long-term Radio Monitoring of the Fast X-Ray Transient EP 240315a: Evidence for a Relativistic Jet.” The Astrophysical Journal Letters 979.2 (2025): L28.

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Even with all we’ve learned about Mars in recent decades, the planet is still mysterious. Most of the mystery revolves around life and whether the planet ever supported any. But the planet teases us with more foundational mysteries, too.

One of those mysteries is the Martian dichotomy: Why are the planet’s northern and southern hemispheres so different?

For some reason, Mars’ southern hemisphere is predominantly highlands and has a higher elevation than the northern hemisphere—about 5km (3 mi) higher. The south also has a thicker crust, is older and is covered in craters.

The northern hemisphere is a vast, smooth plain with a thinner crust and fewer craters. It is also less magnetized than the south.

Elevation map of Mars, based on data obtained by the Mars Global Surveyor’s MOLA instrument. The northern hemisphere is a smooth plain with a lower elevation than the southern hemisphere. Image Credit: NASA/GSFC

Scientists have been puzzling over this dichotomy and have proposed different reasons for it. One leading theory involves a massive impact. Some researchers using geophysical modelling have suggested that a Pluto-sized body struck Mars early in its history. The impact could’ve created the northern lowlands as a gigantic impact basin.

Other researchers have proposed that the planet’s internal (endogenic) processes created the dichotomy. Plate tectonics or mantle convection could’ve been behind it.

Either way, the dichotomy is fundamental to understanding Mars. We can’t understand the planet’s evolution without revealing the mystery behind the dichotomy. This is why NASA and the DLR launched the InSight lander, which reached the Martian surface in November 2018.

The lander’s name stands for Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport. Among its instruments was SEIS, the Seismic Experiment for Interior Structure. SEIS helped scientists better understand Marsquakes by detecting and measuring hundreds of them. It also helped them measure crustal thickness and investigate the mantle. InSight’s data also helped them constrain the size of Mars’ core.

Scientists are still working with InSight’s data, and a new research letter published in the AGU’s Geophysical Research Letters suggests that Mars’ convection is behind the Martian dichotomy. It’s titled “Constraints on the Origin of the Martian Dichotomy From Southern Highlands Marsquakes.” The authors are Weijia Sun from the Chinese Academy of Sciences and Professor and geophysicist Hrvoje Tkalcic from the Australian National University.

The authors state the Martian dichotomy in clear terms: “The Martian hemispheric dichotomy is delineated by significant differences in elevation and crustal thickness between the Northern Lowlands and Southern Highlands.” The altitude difference is about equal to the height of the tallest mountains on Earth.

This research is based on a cluster of Marsquakes in the Terra Cimmeria region of the southern highlands. “We analysed waveform data from so-called low frequency marsquakes captured by NASA’s InSight seismograph on Mars,” Professor Tkalcic said. “In doing this, we located a cluster of six previously detected, but unlocated marsquakes in the planet’s southern highlands, in the Terra Cimmeria region.”

These quakes gave the researchers new seismic data from previously unstudied regions, which is significant because it allows them to compare the data to seismic data from other regions, especially from the Cerberus Fossae region in the northern lowlands.

A MOLA map showing the boundaries of Terra Cimmeria and other nearby regions. Image Credit: By Jim Secosky modified NASA image. Public Domain.

Cerberus Fossae is a series of near-parallel fissures on Mars. Scientists think they were created by the Tharsis volcanoes to the east and Elysium to the west.

The image on the left is a vertical plan view of Cerberus Fossae. The pair of trenches are very young and formed from volcanic activity only a few million years ago. Image Credit: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO. The image on the right shows Cerberus Fossae in context. Image Credit: NASA MGS MOLA Science Team.

The researchers worked with InSight’s seismic data and improved the signal-to-noise ratio. That improvement allowed them to pinpoint the locations of the marsquakes. “Here, we improve the signal-to-noise ratios and determine the locations of the low-frequency marsquakes recorded during the InSight mission. We find a new cluster of marsquakes in Terra Cimmeria, Southern Highlands, in addition to those previously located in Cerberus Fossae, Northern Lowlands,” they write.

The researchers used what’s called the spectral ratio method to determine the quality of the waves. In this context, quality refers to how quickly seismic waves lose energy as they travel through the Martian interior. It’s expressed as a value for ‘Q’ which was different between the Cerberus Fossae region and the Terra Cimmeria region.

This figure from the research letter illustrates some of the work. (a) shows the topography with location names marked. (b) shows Marsquake locations from InSight Marsquake Service (2023) in blue stars, and this study’s locations are in red stars. (c)–(e) are enlarged views of Marsquake locations for clarity, with (c) showing the new cluster of quakes. The yellow triangle shows InSight’s location. Image Credit: Sun and Tkalcic 2025.

“Using the spectral ratio method, we estimate the quality factor Q in the range 481–543 for Terra Cimmeria versus 800–2,000 determined for Cerberus Fossae,” the researchers explain. A higher Q in the Southern Highlands’ Terra Cimmeria indicates that seismic waves there ‘attenuate’ or lose energy more quickly.

Such a large difference in Q between regions indicates that the subsurfaces are substantially different from one another. Temperature and mantle convection could be the key. “The attenuation difference might be linked to the temperature differences between the two hemispheres, along with more vigorous convection beneath the Southern Highlands,” the paper states.

“The data from these marsquakes, when compared with the well-documented northern hemisphere marsquakes, reveal how the planet’s southern hemisphere is significantly hotter compared to its northern hemisphere,” Professor Tkalcic said. “Understanding whether convection is taking place offers clues into how Mars has evolved into its current state over billions of years.”

Researchers’ primary goal in studying the Martian dichotomy has been to determine whether endogenic or exogenic processes or events are responsible. However, the impact theory is hampered by timing. There are significant geochronological constraints for giant impacts on Mars. Crater data, mineral distribution, and the presence of river channels all conflict with the impact hypothesis, which most researchers suggest had to have happened early in the Solar System’s history.

“These seismological observations, together with geochronological constraints of giant impacts, reinforce the “endogenic” hypothesis that mantle convection causes the crustal dichotomy,” they explain.

This figure from the research letter illustrates some of the results. It shows the endogenic origin of the Martian dichotomy from seismological observations. “Although other mechanisms may contribute to attenuation (dislocations, melt, pre-melting effects), we infer that the observed attenuation difference stems mainly from the temperature difference,” the authors write. “Our interpretation <in Figure 4> is compatible with the finding that the mantle temperature is substantially higher beneath the Southern Highlands than in the Northern Lowlands.” Image Credit: Sun and Tkalcic 2025.

Are these findings a breakthrough in understanding the Martian dichotomy? Possibly. Compared to our seismic probings of Earth’s interior, Mars is practically undiscovered.

“On Earth, we have thousands of seismic stations scattered around the planet. But on Mars, we have a single station, so the challenge is determining the location of these marsquakes when you have only a single instrument,” Professor Tkalcic said.

It seems that the researchers have met that challenge.

“These findings, supported by geochemical analysis of Martian meteorites, provide valuable in situ seismological observations that support the “endogenic” hypothesis, suggesting that mantle convection plays a crucial role in forming the Martian crustal dichotomy,” the authors explain.

The post A Marsquake Reveals Why Mars has Two Very Different Hemispheres appeared first on Universe Today.

The Vera C. Rubin Observatory, previously known as the Large Synoptic Survey Telescope (LSST), will be the first observatory of its kind. Jointly funded by the National Science Foundation (NSF) and the Department of Energy (DOE), Rubin will conduct the Legacy Survey of Space and Time (LSST) – a 10-year survey of the southern hemisphere. The observatory is expected to collect 15 terabytes of data a night, which will be used to create an ultra-wide, ultra-high-definition, time-lapse record of the cosmos, containing tens of billions of stars, galaxies, and astronomical objects.

After ten years of construction, the Vera C. Rubin Observatory is less than one year away from starting this revolutionary observation campaign. In preparation for this, the observatory recently completed a series of full-system tests using an engineering test camera. With this milestone complete, the stage is now set for the installation of the 3200-megapixel LSST Camera (LSSTCam), the world’s largest digital camera. Once mounted on the Simonyi Survey Telescope, the observatory will have finished construction and be ready to collect its first light.

The engineering test camera, the Commissioning Camera (ComCam), is a much smaller version of the LSSTCam. It relies on a mosaic of nine 3.2-megapixel Charge-Coupled Device (CCD) sensors, providing a total area coverage of 144 megapixels – about twice the size of a full Moon. During the ComCam engineering test campaign, which took place from October 24th to December 11th, 2024, the camera acquired approximately 16,000 exposures to test the Rubin Observatory’s hardware, software, and data pipeline.

A single test engineering image from the very first night of the ComCam campaign in the context of the coverage provided by the LSSTCam. Credit: RubinObs/NOIRLab/SLAC/NSF/DOE/AURA.

The tests were conducted by Rubin’s international commissioning team, composed of hundreds of engineers, scientists, and observing specialists. According to a statement issued by the Rubin Observatory, the test included verifying that the telescope’s complex systems were all working together, testing the early image quality in all six of the system’s filters, and running the data processing pipelines. They also verified that the system can transmit large amounts of data from the observatory to the Department of Energy’s SLAC National Accelerator Laboratory.

They also confirmed the Active Optics System (AOS), which maintains the precise positions and shapes of the telescope’s three large mirrors. The Simonyi Survey Telescope, the camera, data systems, networks, and everyone involved in the engineering test were said to have performed exceptionally well. The test delivered high-quality images within the first hours, even though most of the detailed optical adjustments and environmental controls were not fully activated. Per the statement:

“Thanks to the dedicated efforts and talents of thousands of people over many years, the telescope had been assembled with all its complex parts positioned correctly to better than about one millimeter. Equally satisfyingly, the high-speed network connecting Chile and the data center at SLAC, the data systems, and the algorithms for analyzing the data worked well, too.”

The LSSTCam has 189 CCD sensors, giving it a field of view roughly 45 times the size of a full Moon – over 21 times that of the ComCam. For the final phase of construction, the LSSTCam will replace the ComCam on the Simonyi Survey Telescope. When coupled with this 8.4-meter (27.5-ft) telescope, the LSTTCam will capture images of very faint and variable objects at an unprecedented rate. The installation will take a few months, followed by the observatory capturing its “First Look” images of the cosmos.

The complete focal plane of the future LSST Camera shows the 189 individual sensors that will produce 3,200-megapixel images. Credit: Jacqueline Orrell/SLAC National Accelerator Laboratory

“The success of the engineering test phase has given a surge of excitement and anticipation to the team,” said Deputy Director for Rubin Construction Sandrine Thomas. “Reaching this milestone has offered a small taste of what is to come once Rubin Observatory begins its 10-year survey.” Once the final testing and verification phase is complete, the Rubin Observatory will begin the most comprehensive data-gathering mission ever performed in the history of astrophysics.

The observatory is named in honor of American astronomer Dr. Vera C. Rubin, whose work was foundational to the theory of Dark Matter. By repeatedly scanning the southern sky with its cutting-edge instruments for a decade, Rubin will create an ultra-high-definition time-lapse record of the cosmos. This data will allow scientists to investigate Dark Matter, Dark Energy, and other mysteries facing astronomers, astrophysicists, and cosmologists today.

Further Reading: Rubin Observatory

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