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A new international study shows that AI-based models can outperform human experts at identifying ovarian cancer in ultrasound images.

Researchers design a new way to more reliably evaluate AI models' ability to make clinical decisions in realistic scenarios that closely mimic real-life interactions. The analysis finds that large-language models excel at making diagnoses from exam-style questions but struggle to do so from conversational notes. The researchers propose set of guidelines to optimize AI tools' performance and align them with real-world practice before integrating them into the clinic.

Hula hooping is so commonplace that we may overlook some interesting questions it raises: 'What keeps a hula hoop up against gravity?' and 'Are some body types better for hula hooping than others?' A team of mathematicians explored and answered these questions with findings that also point to new ways to better harness energy and improve robotic positioners.

Hula hooping is so commonplace that we may overlook some interesting questions it raises: 'What keeps a hula hoop up against gravity?' and 'Are some body types better for hula hooping than others?' A team of mathematicians explored and answered these questions with findings that also point to new ways to better harness energy and improve robotic positioners.

Steroid hormones are among the most widespread aquatic micropollutants. They are harmful to human health, and they cause ecological imbalances in aquatic environments. Researchers investigated how steroid hormones are degraded in an electrochemical membrane reactor with carbon nanotube membranes. They found that adsorption of steroid hormones on the carbon nanotubes did not limit the hormones' subsequent degradation.

Artificial intelligence has the potential to improve the analysis of medical image data. For example, algorithms based on deep learning can determine the location and size of tumors. This is the result of AutoPET, an international competition in medical image analysis. The seven best autoPET teams report on how algorithms can detect tumor lesions in positron emission tomography (PET) and computed tomography (CT).

A research team has shown wearable electronic textiles (e-textiles) can be both sustainable and biodegradable.

Chlorine plays an essential part in daily life, from keeping pools clean to preserving food. Now, a team of chemists developed a more environmentally friendly way to integrate chlorine into chemical building blocks for medications, plastics, pesticides and other essential products while reducing costs.

Researchers developed a type of infrared photodiode that is 35% more responsive at 1.55 m, the key wavelength for telecommunications, compared to other germanium-based components.

Researchers developed a type of infrared photodiode that is 35% more responsive at 1.55 m, the key wavelength for telecommunications, compared to other germanium-based components.

A research team has developed a method for extracting gold from electronics waste, then using the recovered precious metal as a catalyst for converting carbon dioxide (CO2), a greenhouse gas, to organic materials.

Scientists have developed a nanopore-based tool that could help diagnose illnesses much faster and with greater precision than current tests allow, by capturing signals from individual molecules.

Potentially habitable exoplanets are so incredibly common that astronomers have started to consider more unusual situations where life might arise. Perhaps life can be found on the moon of a hot Jupiter or lingering in the warm ocean of a rogue planet. Recently, there has even been the idea that habitable worlds might orbit white dwarfs. We know some white dwarfs have planets, and despite lacking nuclear fusion, white dwarfs do emit enough light and heat to have a habitable zone. But the question remains whether a planet could retain a water-rich environment through the red giant stage of a star before it becomes a white dwarf. This is the focus of a new study on the arXiv.

The study starts by stating the obvious. Any habitable world around a main-sequence star will likely be stripped of its atmosphere and water as the star swells to a red giant. By the time the star becomes a white dwarf, any planet that was habitable will be barren, if not consumed by its star. The work then goes on to consider more distant worlds in a system. Perhaps a cold and icy hycean world might become habitable in the white dwarf stage.

It turns out there are two critical stages. The first is that an ocean world would need to retain a large portion of its water during the dying stage of the main sequence star. As you might expect, the more distant a planet is from its star, the more water it retains. For a sunlike star, an ocean world would need to be more than three times Earth’s distance to retain water. To retain vast oceans similar to Earth, the planet would have to be about 10 AU away, or roughly the distance of Saturn.

Water retention for planets at different distances. Credit: Becker, et al

The second critical stage is orbital migration. Once the star becomes a white dwarf, an ocean world at Saturn’s orbit would be an ice planet far beyond the habitable zone. To become a living world, it would need to move inward to a close, warm orbit. This is possible both through interaction with the nebula formed during the red giant stage, as well as through gravitational interactions between planets. Our own solar system, for example, had a migration phase in its youth. As the study shows, however, the timing of this migration is critical. If the inward migration of a world happens too soon, then much of the water will boil off. If it happens too late, then the system will have stabilized to the point that the world won’t be able to enter the habitable zone.

Overall, the study finds that most worlds around a white dwarf will either be dry before entering the habitable zone, or retain water and remain at the outer edge of the system. But as the authors point out, it is *possible* for an outer hycean world to migrate at just the right time to retain water and become a warm Earth-like world. Not likely, but possible.

So finding a habitable planet around a white dwarf is a long shot. But given how easy it might be to study the atmospheres of these worlds, it’s certainly worth taking a look.

Reference: Becker, Juliette, Andrew Vanderburg, and Joseph Livesey. “The Fate of Oceans on First-Generation Planets Orbiting White Dwarfs.” arXiv preprint arXiv:2412.12056 (2024).

The post Could Habitable White Dwarf Planets Retain Their Oceans? Maybe. appeared first on Universe Today.

One of the more daunting questions related to astrobiology—the search for life in the cosmos—concerns the nature of life itself. For over a century, biologists have known that life on Earth comes down to the basic building blocks of DNA, RNA, and amino acids. What’s more, studies of the fossil record have shown that life has been subject to many evolutionary pathways leading to diverse organisms. At the same time, there is ample evidence that convergence and constraints play a strong role in limiting the types of evolutionary domains life can achieve.

For astrobiologists, this naturally raises questions about extraterrestrial life, which is currently constrained by our limited frame of reference. For instance, can scientists predict what life may be like on other planets based on what is known about life here on Earth? An international team led by researchers from the Santa Fe Institute (SFI) addressed these and other questions in a recent paper. After considering case studies across various fields, they conclude that certain fundamental limits prevent some life forms from existing.

The research team was led by Ricard Solé, the head of the ICREA-Complex Systems Lab at the Universitat Pompeu Fabra and an External Professor at the Santa Fe Institute (SFI). He was joined by multiple SFI colleagues and researchers from the Institute of Biology at the University of Graz, the Complex Multilayer Networks Lab, the Padua Center for Network Medicine (PCNM), Umeå University, the Massachusetts Institute of Technology (MIT), the Georgia Institute of Technology, the Tokyo Institute of Technology, and the European Centre for Living Technology (ECLT).

Artist’s impression of Earth during the Archean Eon. Credit: Smithsonian National Museum of Natural History

The team considered what an interstellar probe might find if it landed on an exoplanet and began looking for signs of life. How might such a mission recognize life that evolved in a biosphere different from what exists here on Earth? Assuming physical and chemical pre-conditions are required for life to emerge, the odds would likely be much greater. However, the issue becomes far more complex when one looks beyond evolutionary biology and astrobiology to consider synthetic biology and bioengineering.

According to Solé and his team, all of these considerations (taken together) come down to one question: can scientists predict what possible living forms of organization exist beyond what we know from Earth’s biosphere? Between not knowing what to look for and the challenge of synthetic biology, said Solé, this presents a major challenge for astrobiologists:

“The big issue is the detection of biosignatures. Detecting exoplanet atmospheres with the proper resolution is becoming a reality and will improve over the following decades. But how do we define a solid criterion to say that a measured chemical composition is connected to life? 

“[Synthetic biology] will be a parallel thread in this adventure. Synthetic life can provide profound clues on what to expect and how likely it is under given conditions. To us, synthetic biology is a powerful way to interrogate nature about the possible.”

The sequence where amino acids and peptides come together to form organic cells. Credit: peptidesciences.com

To investigate these fundamental questions, the team considered case studies from thermodynamics, computation, genetics, cellular development, brain science, ecology, and evolution. They also consider previous research attempting to model evolution based on convergent evolution (different species independently evolve similar traits or behaviors), natural selection, and the limits imposed by a biosphere. From this, said Solé, they identified certain requirements that all lifeforms exhibit:

“We have looked at the most fundamental level: the logic of life across sales, given several informational, physical, and chemical boundaries that seem to be inescapable. Cells as fundamental units, for example, seem to be an expected attractor in terms of structure: vesicles and micelles are automatically formed and allow for the emergence of discrete units.”

The authors also point to historical examples where people predicted some complex features of life that biologists later confirmed. A major example is Erwin Schrödinger’s 1944 book What is Life? in which he predicted that genetic material is an aperiodic crystal—a non-repeating structure that still has a precise arrangement—that encodes information that guides the development of an organism. This proposal inspired James Watson and Francis Crick to conduct research that would lead them to discover the structure of DNA in 1953.

However, said Solé, there is also the work of John von Neumann that was years ahead of the molecular biology revolution. He and his team refer to von Neumann’s “universal constructor” concept, a model for a self-replicating machine based on the logic of cellular life and reproduction. “Life could, in principle, adopt very diverse configurations, but we claim that all life forms will share some inevitable features, such as linear information polymers or the presence of parasites,” Solé summarized.

The first implementation of von Neumann’s self-reproducing universal constructor. Three generations of machines are shown: the second has nearly finished constructing the third. Credit: Wikimedia/Ferkel

In the meantime, he added, much needs to be done before astrobiology can confidently predict what forms life could take in our Universe:

“We propose a set of case studies that cover a broad range of life complexity properties. This provides a well-defined road map to developing the fundamentals. In some cases, such as the inevitability of parasites, the observation is enormously strong, and we have some intuitions about why this happens, but not yet a theoretical argument that is universal. Developing and proving these ideas will require novel connections among diverse fields, from computation and synthetic biology to ecology and evolution.”

The team’s paper, “Fundamental constraints to the logic of living systems,” appeared in Interface Focus (a Royal Society publication).

Further Reading: Santa Fe Institute, Interface Focus

The post Is There a Fundamental Logic to Life? appeared first on Universe Today.

A new type of crystal that absorbs heat when released from extreme pressure could lead to climate-friendly refrigerators and air conditioners

Cracking the chicken-and-egg problem of utilizing resources in space has been a difficult challenge for over half a century. Getting enough infrastructure built up is necessary to collect those resources effectively, but doing so is too expensive without using the resources themselves. Trying to crack that problem has been the focus of a variety of space exploration enthusiasts, and one of them, Don Barker, is currently the Gateway HALO Utilization & Visiting Vehicle Integration Lead at ARES Corporation. He published a paper in 2020 that detailed how the space exploration industry could use a modified version of a framework from the oil and gas industry, which he calls the Planetary Resource Management System (PRMS), to calculate where we should focus on settlement efforts.

PRMS is set up as a two-step process: finding resources and then developing the technology to utilize them. Ideally, those technologies would advance to a point where those resource processes would be commercially viable. Let’s look at the process of finding the resource first.

The most basic level of resource finding is a remote sensing picture around 100m or more per pixel. This can be done with a relatively good camera on board an orbiting spacecraft. Next up would be a remote image between 5m and 100m per pixel, combined with geophysical evidence that a resource is available. Importantly, this would be combined with a resource assessment that includes estimations like economic impact and technological availability.

Fraser discusses what ISRU is and why it’s important.

A final step of the PRMS’s “prospecting criteria” is a remote sensing image of less than 5m per pixel resolution, geophysical evidence of a resource’s presence, and proof that it is accessible using current technology. This would again be combined with an assessment of the economic viability of recovery to ensure that the effort would be supported in the long term.

Technology, such as surface miners or extraterrestrial drilling rigs, enables the accessibility of the resources the prospecting projects would find. Three categories of recoverable resources – possible, probable, and proved – go along with the three categories of prospecting listed above. The framework also uses a metric called Estimated Ultimate Recovery (EUR) to reflect how much of a potential resource deposit could ultimately be mined. 

Calculating the various numbers for a deposit of a given material (such as water ice on the Moon), the framework can be combined with overall mission architecture and human exploration goals to determine the importance of that particular deposit to “mission success.” This is where things get tricky, as “mission success” is primarily defined by whoever pays for that mission.

ISRU would be a critical technology in any crewed Mars mission.

NASA is the largest funder of these types of projects for now, but even they don’t necessarily abide by this framework. Last year, they canceled the one rover project, VIPER, which could have added to our prospecting knowledge of the lunar south pole. Such a lack of foresight frustrated Dr. Barker, who bemoans the lack of structured support for permanently implementing a human presence off the planet rather than scientific outposts similar to McMurdo station in Antarctica. 

For now, that is the best we can hope for in terms of a sustained human presence in space – the main driving force behind Artemis, NASA’s project to get humans back to the Moon, is to set up a scientific outpost rather than start utilizing resources to supply a permanent habitat. However, the agency has done some research on that topic. VIPER would have been a great addition to that research, and the agency claims that other missions will cover its scientific objectives. But suppose it continues to cut funding to programs that could help implement the framework. In that case, a different organization will likely have to take on the mantle of utilizing resources in situ. 

SpaceX seems to be the leader in that area, but it is currently focused, rightfully, on building bigger, better, and cheaper rockets. If and when it is able to more closely focus on its stated goal of making humanity interplanetary, then at least it will have a framework for utilizing the resources needed to do so.

Learn More:
DC Barker – Lunar and off Earth resource drivers, estimations and the development conundrum
UT – What is ISRU, and How Will it Help Human Space Exploration?
UT – NASA Wants to Learn to Live Off the Land on the Moon
UT – Researchers Developed a Test Bed For Separating Valuable Material on the Moon

Lead Image:
ISRU system concept for autonomous construction on Mars.
Credit: NASA/JPL-Caltech

The post Using an Oil Industry Framework to Map Space Resources appeared first on Universe Today.

A robotic hand uses fingertip sensors and AI to determine how firmly to grip before closing in on an object, overcoming a persistent problem for prosthetics

This is the third and last of a series of posts on the misguided concept of “agency and purpose in biology,” which one can take as the statement that “organisms have goals, and guide their own development and evolution towards those goals”.

In my first post, on December 23, I noted that the John Templeton Foundation (JTF) was spending millions of dollars funding grants on the science of “purpose and agency”. I pointed out one JTF  grant that just ended, which handed out $14.5 million to a consortium of investigators to study this topic.  And the JTF intends to continue funding this area:

Science of purpose. We are looking for experimental and theoretical research projects that will provide insight into the purposive, goal-directed, or agential behaviors that characterize organisms and various components of living systems. Researchers who have familiarity with our ongoing work in this area are especially encouraged to apply.

If you know the JTF, you’ll understand why they keep replenishing a trough full of grant money for such studies, for John Templeton (a mutual-fund billionaire and a believer) funded his Foundation with the intent of showing that science itself gave evidence for “spiritual reality”, aka a god or gods.  Although some of the investigators supping at the trough deny that they’re engaged in teleology, much less giving evidence for divinity, all of their work feeds into the JTF’s mission, and the authors of an article just published online at the Journal of Evolutionary Biology (JEB) agree: the idea of teleology sneaks into many of these papers.

In my second post, on December 26, I analyzed one of the JTF-funded papers often cited to support the idea of agency and purpose in organisms, a paper in BioEssays by Sonia E. Sultan et al. I found it vacuous and intellectually confusing, mistaking “purpose” and “agency” for the results of natural selection and, in the end, making the ID-friendly argument that neo-Darwinism cannot explain the origins of “novel, complex traits”. That assertion alone discredits the paper, for the one paper that actually tried, using conservative assumptions, to mathematically model the origin of a complex trait (the camera eye), did so very successfully. No problems encountered! The purpose-and-agency folks’ view is that “since we don’t fully understand how an eye/wing/brain evolved, there must have been something beyond natural selection involved.”  I suspect you know the fallacy of this argument.

Here are two concepts of agency advanced by Sultan et al and quoted in the paper below:

● “Biological agency—the capacity of living systems […] to participate in their own development, maintenance, and function” (Sultan et al 2022, p. 1);

● “Organisms themselves actively shape their own structure and function” (Sultan et al 2022, p. 4);

Now, a paper by James DiFrisco and Richard Gawne, published in JEB, takes apart the whole misguided notion and program of “agency and purpose” in evolution, and cites a lot of papers that tried to advance misguided ideas similar to those of Sultan et al. The title of the new paper is below, but if you click on it you will go to a truncated version of the article. However, you  can read the entire paper as a pdf file available for free here.

Here are what I take as the paper’s important points:

A.) The idea that organisms direct their own development and evolution through some nebulous, non-neo-Darwinian process is incorrect. Everything touted as “purposeful” and “the results of agency” can be explained by natural selection molding organisms’ responses to a changing environment, both within one lifetime or across generations. As DiFrisco and Gawne say, goal-directedness “is an adaptation due to natural selection.”  In my own example, cats and other mammals often grow longer fur during cold seasons because natural selection has favored genes that give organisms the capacity to put out more fur when their bodies detect cold weather. This is simple natural selection, and there is no “purpose” or “agency” involved.

B.)  Some of the papers on purpose and agency aim to “rescucitate the Aristotelian view of biological purpose and teleology as real rather than merely apparent”, so some authors really do have a teleological bent, one that you can find in some works of the “Extended Evolutionary Synthesis.”

C.) The agency and purpose trope is, in the end, a metaphor that does no explanatory work nor promotes further research. Only the framework of neo-Darwinism can help us understand the origin of adaptations.

D.) The only “true” purpose and agency we see in biology is that which we see in the cognition of organisms capable of responding to environmental challenges by thinking rather than by a mechanical response.  But even the p&a authors are the first to aver that this is not the sense in which they use these terms. In truth, as a hard determinist I see even cognition as a mechanical process and not something different in principle from a bacterium moving towards food, but this is not so important in this debate since the “cognition” view of purpose isn’t the subject of scientific work by the Templeton-funded authors.

I’ll quote the authors’ own conception of their aims as given in the JEB paper:

Box 1: The central claims of this paper.

1. An organism’s capacity for goal-directed behavior does not itself explain any biological phenomena. Apparently goal-directed behaviors are, instead, something to be explained as an evolved characteristic of biological systems.

2. The capacity for goal-directed behavior (outside of human cognition, which can set arbitrary, novel goals) is explained by Darwinian natural selection acting in populations of individuals.

3. Notions such as self-determination, or the idea that the whole organism is a cause of its own developmental or physiological processes, are either empirically untestable, or restatements of ordinary questions about which causal mechanisms at which scales influence events.

4. Downward causation and context-dependence are “mechanistic” in the sense relevant to experimental biology. They are not mysterious processes that require adopting the teleological form of investigation provided by an agency perspective.

5. Rejection of molecular reductionism or determinism does not necessitate a commitment to the idea of biological agency. Researchers need not embrace the agency perspective in order to acknowledge the importance of multi-level complexity, emergence, and downward causation.

6. The idea that biological goal-directedness is a product of natural selection rather than the inherent agency of organisms does not require commitment to the idea that all traits are adaptations. It is compatible with genetic drift, mutation, and developmental constraints playing an important role in evolution.

7. Agency is a psychological concept with origins in heuristic ascriptions of intentionality. Accordingly, it is applicable only where psychological explanations are useful—i.e., when explaining the behavior of humans and possibly other neurologically complex organisms such as primates.

8. Agency is not an empirically meaningful property, and incorporating the agency concept into experimental practices will not contribute to progress in biology.

And a few quotes that underline their contentions (indented). First, the important of natural selection in explaining adaptations:

It is important to recognize that the attribution of non-fitness-related goals to an organism can only be empirically grounded in the psychological case, where investigators can ask another human being to report on their internal cognitive states. For systems that lack the capacity to report on such states, the attribution of goals is empirically unmoored and arbitrary (see Fig 1). Is it the goal of a given stem cell to differentiate? (Manicka and Levin 2019; Levin 2021; 2022) Or, if the stem cell fails to differentiate and dies, was that really its goal? In order for goal-attributions to explain anything, goals would need to be linked to some empirically detectable feature of the system other than the actual outcomes of its behavior. Otherwise, these explanations would be circular and uninformative. It is not clear that this can be done without reference to natural selection.

The intellectual and biological vacuity of adding “purpose” to already-existing explanations:

Even if one allows explanations based on agency, it is difficult to see how such explanations could be useful for understanding an ordinary biological process—e.g., wound healing. To explain why a wound heals following injury, the statement that it is because the system possesses agency and pursues the goal of healing wounds is not useful from a scientific point of view. This is because agency is not an experimentally meaningful property that can be subjected to tests as to whether its presence or absence influences wound-healing. The “goal” of wound-healing is not something that can be detected or measured, but would have to be inferred and attributed ex post facto based on the system’s actual behavior (see above, “Agency and goal-directedness”). This procedure cannot predict that wound-healing fails in pathological cases (e.g., tumorigenesis), nor can it explain why such malfunctions do or do not happen. In the context of modern biological research, wound-healing is understood to be explainable in terms of complex positive and negative feedback mechanisms in which a wide array of signaling molecules mediate the progression through cell- and tissue-level processes, from wound detection to hemostasis, inflammation, cell proliferation, re-epithelialization, and tissue remodeling (Singh et al 2017; Rodrigues et al 2019). These feedback mechanisms are tuned to parameter values conducive to survival and reproduction because of natural selection.

Between mechanistic explanations and adaptive ones (Tinbergen 1963; Stearns 1982), there is no obvious role for a distinct form of explanation based on agency.

How could you investigate how wounds heal by even considering the idea of “purpose and agency”?  As the authors note, there is no real “goal” here, but merely the sorting-out of genes that have different effects on wounds, with the genes that contribute to healing leaving more copies (their bearers survive and/or reproduce better).  That’s simply natural selection.  Ergo, there is no scientific benefit of JTF giving lots of dollars to study agency and purpose. They could give money for studying neo-Darwinian explanations, which we know are often the way to go, but doing so would simply justify scientific materialism, something anathema to JTF, as it leaves out god.

Finally, one more quote, as you can read the paper yourself (it’s written very clearly and should be accessible to those with a smidgen of biology knowledge):

An initial difficulty with the notion of self-determination centers on the self. It is not clear how to interpret expressions such as “the capacity of living systems […] to participate in their own development.” Development is the process of an organism going through the stages of its life cycle. It is not something separate from the organism. So how can an organism fail to participate in its development? If we suppose that the development of a given organism is fully determined by a set of underlying molecular factors, it is still the development of that particular organism rather than of another entity. It is also difficult to interpret the statement that “typical descriptions […] treat organisms [as] separate from and passive to the conditions under which they develop and evolve” (Nadolski and Moczek 2023, p. 3). If this refers to environmental conditions, it is an ordinary question of the relative causal importance of internal versus external factors. If it refers to internal conditions, however, the statement veers into obscurity. How can an organism be or separate from, or passive to, a process of development of itself?

This quote—and indeed, the whole paper—shows that the “purpose-and-agency” school is either engaged in a semantic rather than a biological argument, they are simply unable to grasp evolution, or they wish to make a name by couching neo-Darwinian mechanisms in “I-have-a-new-paradigm” language. .  Indeed, epigenetics (at least some forms) were not part of the modern synthesis, but neither do they play into notions of agency and purpose. Epigenetic modifications can be evolved features of organisms that are ultimately coded in the genome, or they can be environmentally-induced modifications of DNA that are rarely adaptive and, at any rate, usually disappear in two or three generations at most, making them useless to explain the evolution of adaptations.

The lesson is twofold. Beware when you see biologists banging on about agency and purpose, and think about natural selection instead. Second, the JTF is throwing away its money on misguided projects. I’d like to ask them to give money to fund real biology, as they have over a billion dollars in endowment, but funding real biology would not advance the JTF’s purpose of finding the numinous using science.

Trans-Neptunian Objects (TNOs) are small planetoids that orbit the Sun beyond Neptune and Pluto. Their dark and icy character contains the remnant of the early solar system, and as such, they have the potential to reveal its history. But since they are small, distant, and dim, TNOs are very difficult to study. We know that different groups of TNOs have unique histories based on their surface colors and orbits. A new study has looked at their spectra, and it reveals a rich diversity unseen before now.

The team used observations from the James Webb Space Telescope (JWST) to capture the spectra of 54 TNOs. They found the planetesimals could be grouped into three categories based on the overall shape of their spectra. Double-dip TNOs have a strong presence of carbon dioxide ice and are the most common of the survey objects. Cliff-type TNOs are reddish and are rich in nitrogen molecules and complex organics. Finally, bowl-type TNOs have dark and dusty surfaces rich in water ice.

The authors argue that these categories formed because of different “ice lines” that existed during the early period of the solar system. That is, beyond a certain distance, temperatures are cold enough for water ice to form. Further out, it becomes cold enough for carbon dioxide ice to form, and so forth. The different categories of TNOs therefore formed at different distances from the Sun, likely before the great migration of the large planets.

This idea is supported by the fact that there is a correlation between the spectral category of TNOs and their orbital types. For example, cold classical TNOs with orbits at the outer edge of the planetary disk are mostly cliff-type TNOs.

The team was also able to connect TNOs to another type of planetoid known as centaurs, which orbit the Sun between Jupiter and Saturn. While the spectra of centaurs differ significantly from those of TNOs, there are enough similar features to identify many centaurs as part of a particular TNO type. The centaur Thereus matches the bowl-type category, for example. On the other hand, some centaurs, such as Okyrhoe don’t fall into any TNO category. This supports the idea that many centaur planetoids were TNOs that migrated inward over time, while others are likely comets that became centaurs after a close approach with Jupiter or Saturn.

In the future, the team would like to gather even more detailed spectra of TNOs. This could tell us the specific histories of each TNO category and how they connect to the early evolution of our solar system.

Reference: Pinilla-Alonso, Noemí, et al. “A JWST/DiSCo-TNOs portrait of the primordial Solar System through its trans-Neptunian objects.” Nature Astronomy (2024): 1-15.

The post The Webb Captures Spectra of Trans-Neptunian Objects, and Reveals a History of Our Solar System appeared first on Universe Today.

Today’s Jesus and Mo strip, called “clowns”, came with this note:

Jesus has been reading Gurwinder again. You should too!

Here are the first two of Gurwinder’s 15 posts on “X” giving useful ideas to get us through 2025:

1. Negative Partisanship:
Many people’s political views revolve not around what they support, but what they oppose. They’re always fighting against something rather than for something, and the constant focus on what they hate makes them nasty and miserable.

— Gurwinder (@G_S_Bhogal) January 1, 2025

And so on to Jesus and Mo, who once again are completely unaware of their hypocrisy: