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In 1960, in preparation for the first SETI conference, Cornell astronomer Frank Drake formulated an equation to calculate the number of detectable extraterrestrial civilizations in our Milky Way. Rather than being a scientific principle, the equation was intended as a thought experiment that summarized the challenges SETI researchers faced. This became known as the Drake Equation, which remains foundational to the Search for Extraterrestrial Intelligence (SETI) to this day. Since then, astronomers and astrophysicists have proposed many updates and revisions for the equation.

This is motivated by ongoing research into the origins of life on Earth and the preconditions that led to its emergence. In a recent study, astrophysicists led by Durham University produced a new model for the emergence of life that focuses on the acceleration of the Universe’s expansion (aka. the Hubble Constant) and the number of stars formed. Since stars are essential to the emergence of life as we knot it, this model could be used to estimate the probability of intelligent life in our Universe and beyond (i.e., in a multiverse scenario).

The study was led by Daniele Sorini, a postdoctoral Research Associate at Durham University’s Institute for Computational Cosmology, and was funded by a European Research Council (ERC) grant. She was joined by John Peacock, a Professor of Cosmology at the Royal Observatory and the University of Edinburgh’s Institute for Astronomy, and Lucas Lombriser, from the Département de Physique Théorique, Université de Genève. The paper that details their findings was recently published in the Monthly Notices of the Royal Astronomical Society.

The Drake Equation is a mathematical formula for the probability of finding life or advanced civilizations in the universe. Credit: University of Rochester

As noted, the Drake Equation was not intended as a tool for estimating the number of extraterrestrial intelligences (ETIs) but as a guide for how scientists should search for life in the Universe. The formula for the equation is:

N = R* x fp x ne x fl x fi x fc x L

Whereas N is the number of civilizations in our galaxy that we might able to communicate with, R* is the average rate of star formation in our galaxy, fp is the fraction of those stars that have planets, ne is the number of planets that can actually support life, fl is the number of planets that will develop life, fi is the number of planets that will develop intelligent life, fc is the number civilizations that would develop transmission technologies, and L is the length of time that these civilizations would have to transmit their signals into space.

In the same sense, the new research does not attempt to calculate the absolute number of intelligent species in the Universe. Instead, the team presents an analytical model for cosmic star formation history to measure the impact of cosmological parameters within the most widely accepted cosmological model. This is none other than the Lambda-Cold Dark Matter (LCDM) model, where Dark Matter and Dark Energy (Lambda) account for roughly 95% of the matter-energy density of the Universe. The remaining 5%, the “ordinary” matter we see every day, is what scientists refer to as baryonic matter (aka. “luminous matter”).

In their paper, the team calculated the fraction of ordinary matter that is converted into stars over the entire history of the Universe based on different Dark Energy densities. Stars are essential to life, creating heavier elements through nuclear fusion that allow for planet formation, biochemistry, and all life as we know it. Their model predicts that the most efficient density for star formation would be 27%, compared to 23% scientists have observed in our Universe. In short, their results suggest that our Universe is an outlier in the context of the multiverse.

Early Dark Energy could have caused early seeds of galaxies (depicted at left) to sprout many more bright galaxies (at right) than theory predicts. Credit: Josh Borrow/Thesan Team

These findings could have significant implications for cosmology and the ongoing debate about whether or not our Universe is “fine-tuned” for life. As Dr. Sorini explained in a Royal Astronomical Society press release:

“Understanding Dark Energy and the impact on our Universe is one of the biggest challenges in cosmology and fundamental physics. The parameters that govern our Universe, including the density of dark energy, could explain our own existence. Surprisingly, though, we found that even a significantly higher dark energy density would still be compatible with life, suggesting we may not live in the most likely of Universes.”

The new model could also provide insight into how differing densities of Dark Energy affect the formation of the Universe and the development of conditions that allow life to emerge. The influence of Dark Energy drives cosmic expansion, causing the large-scale structures of the Universe (galaxies and galaxy clusters) to move farther and farther apart. For life to develop, matter must be able to clump together to form stars and planets and remain stable for billions of years – since evolution is a long-term process lasting billions of years.

Another takeaway from this research is that star formation and the evolution of the large-scale structure of the Universe achieve a balance over time. This balance determines the optimal value of Dark Energy density needed for the emergence of life and the eventual development of intelligent life. Said Prof. Lombriser: “It will be exciting to employ the model to explore the emergence of life across different universes and see whether some fundamental questions we ask ourselves about our own Universe must be reinterpreted.”

The Drake Equation may need additional parameters, including a Lambda energy density (ld) and a multiverse (mv) parameter. Regardless, the search for life and the question of how it can arise endure, much like Frank Drake’s equation itself!

Further Reading: Royal Astronomical Society, MNRAS

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The Pentagon office in charge of fielding UFO reports says that it has resolved 118 cases over the past year, with most of those anomalous objects turning out to be balloons. But it also says many other cases remain unresolved.

This year’s legally mandated report from the Department of Defense’s All-Domain Anomaly Resolution Office, or AARO, also identifies areas of the world that seem to be hotspots for sightings of unidentified flying objects. Such objects have been re-branded as unidentified anomalous phenomena, or UAPs.

Today’s report come just one day after a House subcommittee hearing about UAPs, during which witnesses — and some lawmakers — voiced concerns about potential alien visitations and undisclosed efforts to gather evidence. In contrast, the Pentagon’s report for the 2023-2024 time period states that, “to date, AARO has discovered no evidence of extraterrestrial beings, activity or technology.”

“AARO has successfully resolved hundreds of cases in its holdings to commonplace objects such as balloons, birds, drones, satellites and aircraft,” the office’s director, Jon Kosloski, said in a news release. “Only a very small percentage of reports to AARO are potentially anomalous, but these are the cases that require significant time, resources and a focused scientific inquiry by AARO and its partners.” 

In the past, U.S. military and intelligence officials have suggested that some UAP sightings may be attributable to intrusions by rival powers such as Russia or China. The Chinese spy balloon that was intercepted and destroyed by Air Force fighter jets last year after crossing over the U.S. serves as a prime example.

AARO’s latest report says that U.S. military aircrews provided two reports over the past year that identified flight safety concerns, and three reports described pilots being trailed or shadowed by anomalous objects. “To date, AARO has no indication or confirmation that these activities are attributable to foreign adversaries,” the report says, but the office is continuing to work with the U.S. intelligence community to investigate the cases.

“None of the reports AARO received during the reporting period indicated that observers suffered any adverse health effects,” the report says.

AARO’s reporting system was established to encourage members of the U.S. military to let the Pentagon know about UAP sightings and take the stigma out of the process. Based on the latest numbers, the strategy seems to be working. Between May 2023 and June 2024, AARO received 757 UAP reports, compared with 291 reports for the period between August 2022 and April 2023.

Here are more statistics from today’s report:

• Of the 757 reports received over the past year, 485 relate to incidents during the yearlong reporting period, and the remaining 272 reports relate to incidents occurring in the 2021-2022 time frame.
• In addition to the 118 resolved cases, another 174 cases have been queued up for closure, pending a final review and approval by AARO’s director. All those cases were attributed to prosaic objects.
• Seventy percent of the closed cases in 2023-2024 were attributed to balloons. Sixteen percent were attributed to drones, 8% to birds, 4% to satellites and 2% to birds.
• AARO determined that 21 cases merited further analysis, based on reported anomalous characteristics or behaviors. Those cases are being studied by AARO’s experts as well as the office’s partners in the intelligence community and the science and tech community. “AARO will provide immediate notification to Congress should AARO identify that any cases indicate or involve a breakthrough foreign adversarial aerospace capability,” the report says.
• The remaining 444 cases received over the past year lacked sufficient data for further analysis. They’ve been placed in an archive and will be revisited if additional data comes to light. AARO says it has 1,652 UAP reports in all.
• In addition to reports from the U.S. military, AARO is receiving reports of sightings by civil and commercial pilots via the Federal Aviation Administration. AARO says 392 of the 757 reports received over the past year came from the FAA.
• AARO says unidentified lights or orb-shaped objects were mentioned most frequently in the subset of UAP reports that included references to visual characteristics. Other reports mentioned cylinders, disks, triangles, squares or exotic objects such as a “green fireball” or “a jellyfish with flashing lights.”

AARO’s global map of UAP reporting hotspots highlights four broad areas: the southeastern U.S. and Gulf of Mexico; the West Coast and Pacific Northwest; the Middle East; and northeastern Asia in the vicinity of Japan and the Korean peninsula. This doesn’t mean the aliens favor those regions. Instead, AARO says the distribution favors a “continued geographic collection bias based on locations near U.S. military assets and sensors operating globally.”

AARO says it’s getting an increasing number of cases that can be traced to sightings of SpaceX’s Starlink satellites. “For example, a commercial pilot reported white flashing lights in the night sky,” the report says. “The pilot did not report an altitude or speed, and no data or imagery was recorded. AARO assessed that this sighting of flashing lights correlated with a Starlink satellite launch from Cape Canaveral, Florida, the same evening about one hour prior to the sighting.”

One of the reports received via the FAA mentioned a possible flight safety issue. “In this instance, a commercial aircrew reported a near miss with a ‘cylindrical object’ while over the Atlantic Ocean off the coast of New York,” the report says. “AARO continues its research into, and analysis of, this case.”

AARO received 18 reports from the Nuclear Regulatory Commission that related to UAP incidents near U.S. nuclear infrastructure, weapons and launch sites. NRC officials attributed all those sightings to drones. One of the incidents, in August 2023, involved the recovery of a crashed drone in the vicinity of the D.C. Cook Nuclear Power Plant in Michigan — but AARO provided no further information about the drone.

What more can be done? In today’s report, AARO says its ability to resolve cases has been constrained due to “a lack of timely and actionable sensor data.”

“AARO continues to address this challenge by working with military and technical partners to optimize sensor requirements, information-sharing processes, and the content of UAP reporting,” the report says. “AARO is also expanding engagement with foreign partners to share information and collaborate on best practices for resolving UAP cases.”

The post Pentagon’s Latest UFO Report Identifies Hotspots for Sightings appeared first on Universe Today.

Popular semaglutide-based drugs used for weight loss may reduce chronic and acute pain, which could make them a promising alternative to opioids

The Daisy World model describes a hypothetical planet that self-regulates, maintaining a delicate balance involving its biogeochemical cycles, climate, and feedback loops that keep it habitable. It’s associated with the Gaia Hypothesis developed by James Lovelock. How can we detect these worlds if they’re out there?

By looking closely at information.

A Daisy World (DW) is inhabited by two types of daisies: white and black. They have different albedos, and the blacks absorb more sunlight and warm the planet, while the whites reflect more sunlight and cool the planet.

As the DW’s star brightens, the planet’s temperature rises. At first, black daisies thrive because they absorb more energy. However, as the planet gets hotter, absorbing more energy becomes undesirable, and the white daisies begin to outcompete the blacks and thrive. As they thrive, they reflect more sunlight and cool the planet.

The result is a delicate homeostasis where the daisies regulate the planet’s temperature and keep it in a habitable range. It can’t get too hot and it can’t get too cold. The DW model shows how life can influence a planet’s climate and create conditions favourable for its own survival.

Earth is not exactly a daisy world, but life on Earth influences the climate. The DW model simply illustrates the concept of basic climate feedback mechanisms.

The ESA’s Sentinel 2 satellite captured this image of an algae bloom in the Baltic Sea in 2015. A ship can be seen moving through it. Algae blooms interact with the climate through feedback loops. Image Credit: Copernicus Sentinel data / ESA.

In new research, scientists from the Department of Physics and Astronomy and the Department of Computer Science at Rochester University wanted to find ways to analyze how planetary systems like biospheres and geospheres are coupled. If there are self-regulating “Daisy Worlds” out there, how can we detect them?

The research is “Exo-Daisy World: Revisiting Gaia Theory through an Informational Architecture Perspective.” The lead author is Damian Sowinski, a research physicist and postdoctoral associate in the Department of Physics and Astronomy at the University of Rochester. The research is awaiting publishing and is not peer-reviewed yet.

The idea is to find a way to detect agnostic biosignatures on exoplanets. Regular biosignatures are specific chemicals like oxygen or methane that can be byproducts of living organisms. Agnostic biosignatures are indications that life is present but don’t rely on identifying which types of organisms might be producing them. Instead, they’re like overarching planetary patterns that living worlds produce.

For the authors, finding agnostic biosignatures begins with information and how it flows.

“In this study, we extend the classic Daisy World model through the lens of Semantic Information Theory (SIT), aiming to characterize the information flow between the biosphere and planetary environment—what we term the information architecture of Daisy World systems,” the authors explain.

Semantic Information Theory has been around since the mid-20th century. It attempts to define meaning in different contexts, how human subjective interpretation affects it, and related concepts in the same vein. It’s taken on a new focus as artificial intelligence and machine learning become more prevalent.

There’s a drive to understand exoplanet atmospheres and environments and to have a way to differentiate between those that may be life-supporting and those that aren’t. This is a complex problem that hinges on agnostic biosignatures.

The JWST captured this atmospheric spectrum of exoplanet K2-18 b showing the presence of methane, which can act as a biosignature. The authors say that information theory can help undercover agnostic biosignatures. Rather than specific chemicals like methane, agnostic biosignatures are patterns that can only be created by a biosphere. Image Credit: NASA, CSA, ESA, R. Crawford (STScI), J. Olmsted (STScI), Science: N. Madhusudhan (Cambridge University)

Agnostic biosignatures are complex patterns and structures that can’t be explained by non-biological processes. There’s also disequilibrium, novel energy transfer, unusual levels of organization at different scales, and cyclical or systematic changes that suggest a biological cause.

A search for agnostic biosignatures can involve complex molecules that need biological synthesis, chemical distributions that require metabolism, unexpected accumulations of specific molecules, and features in an atmosphere or on a planetary surface that require biological maintenance.

Some examples of agnostic biosignatures on Earth are methane and oxygen co-existing in the atmosphere, the ‘Red Edge‘ in Earth’s vegetation spectrum, and daily or seasonal cycles of gas emissions.

The Red Edge is a region of rapid change in vegetation reflectance in the near-infrared (NIR). It could be useful in detecting vegetation on exoplanets. Image Credit: Seager et al. 2024.

“The search for life on exoplanets requires the identification of biosignatures, which rely on life having
significantly altered the spectroscopic properties of a planet. Thus, exoplanetary life searches focus not
on detecting individual organisms but on identifying the collective effects of life on the planetary system—what we refer to as exo-biospheres,” the authors explain.

In short, we can’t study biosignatures without studying biospheres. In doing so it’s critical to understand where and how an exo-biosphere reaches a “mature” state where they exert a strong influence on the atmosphere, hydrosphere, cryosphere, and lithosphere, collectively known as the geosphere. Once they’re mature and exert a strong influence, they’re in line with the Daisy World hypothesis.

The authors aim is to study how information flows between a biosphere and the planetary environment. To do this, they modelled potential conditions on M-dwarf exoplanets and came up with equations that describe the co-evolution of the daisies on these worlds with their planetary environments. They created what they term an ‘information narrative’ for exo-Daisy Worlds (eDWs).

Typically, the homeostatic feedback in DWs rests on physical quantities like radiation fluxes, albedos, and plant life coverage fractions. That’s the physical narrative. However, the researchers used Semantic Information Theory to derive a complementary narrative based on how information flows. In their work, SIT focuses on correlations between an agent—the biosphere—and an environment and how those correlations benefit the agent.

Their model showed that as stellar luminosity rises, the correlations between the biosphere and its environment intensify. The correlations correspond to distinct phases of information exchange between the two. This leads to the idea of rein control, a control exerted by flora through the positive and negative differences of their albedos compared to the bare ground. This is how the biosphere exerts a regulatory influence on a planet’s climate. In their informational narrative, the planetary temperatures are more constrained “at the cooler and warmer boundaries of the bearable temperature range.”

Not all of the information that flows between the biosphere and the environment is relevant. The biosphere doesn’t use all of it because some of it doesn’t help the biosphere maintain control. The authors say that by analyzing all this information according to information theory, they can determine which information, and when and how, it contributes to its own viability.

The Daisy World model is instructive, but it’s a toy model. For example, it doesn’t include stochastic events like volcanic eruptions. But the big question is how does it relate to exobiospheres?

The authors say that their work shows the potential in using approaches like SIT to understand how exoplanets and their biospheres co-evolved like they have on Earth. More realistic models will be necessary that include more of the complex networks of interactions between an exoplanet’s living and non-living systems. The biosphere processes information in ways that non-living systems don’t, so information-centric systems can undercover agnostic biosignatures in ways that physical or chemical models can’t.

“As a result, the next step in our research program will involve applying SIT and other information-theoretic approaches to more complex models of coupled planetary systems,” the authors conclude.

The post A New Way to Detect Daisy Worlds appeared first on Universe Today.

Physical cash not only influences how much we spend but also fosters a profound sense of psychological ownership that digital payments cannot replicate, according to new research.

Water, a molecule essential for life, has unusual properties -- known as anomalies -- that define its behavior. However, there are still many enigmas about the molecular mechanisms that would explain the anomalies that make the water molecule unique. Deciphering and reproducing this particular behavior of water in different temperature ranges is still a major challenge for the scientific community. Now, a study presents a new theoretical model capable of overcoming the limitations of previous methodologies to understand how water behaves in extreme conditions.

Scientists create biodiesel with electrocatalysis and bioconversion.

Researchers have created a headphone prototype that allows listeners to hear people speaking within a bubble with a programmable radius of 3 to 6 feet. Voices and sounds outside the bubble are quieted an average of 49 decibels, even if they're louder than those in the bubble.

Researchers have created a headphone prototype that allows listeners to hear people speaking within a bubble with a programmable radius of 3 to 6 feet. Voices and sounds outside the bubble are quieted an average of 49 decibels, even if they're louder than those in the bubble.

Researchers have devised a mathematical approach to predict the structures of crystals -- a critical step in developing many medicines and electronic devices -- in a matter of hours using only a laptop, a process that previously took a supercomputer weeks or months.

Researchers have devised a mathematical approach to predict the structures of crystals -- a critical step in developing many medicines and electronic devices -- in a matter of hours using only a laptop, a process that previously took a supercomputer weeks or months.

A new study determines that just four policies can reduce mismanaged plastic waste -- plastic that isn't recycled or properly disposed of and ends up as pollution -- by 91% and plastic-related greenhouse gasses by one-third. The policies are: mandate new products be made with 40% post-consumer recycled plastic; cap new plastic production at 2020 levels; invest significantly in plastic waste management -- such as landfills and waste collection services; and implement a small fee on plastic packaging. This policy package also delivers climate benefits, reducing emissions equivalent to taking 300 million gasoline-powered vehicles off the road for one year.

Capturing carbon dioxide from the hot industrial exhaust of cement and steel plants requires cooling the exhaust from around 200 C to 60 C so that liquid amines can react with the CO2. Chemists have now created a new type of metal-organic framework that captures CO2 at high temperatures, avoiding the need to expend energy and water to cool the exhaust. The MOF opens up a new field of high-temperature gas capture.

Satellite images reveal that when conditions are right, the pollution from industrial hotspots can cause snow to fall downwind and punch holes in clouds

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In this special solo episode, Michael Shermer reflects on the 2024 election.

In March 2021, astronomers observed a high-energy burst of light from a distant galaxy. Assigned the name AT 2021hdr, it was thought to be a supernova. However, there were enough interesting features that flagged as potentially interesting by the Automatic Learning for the Rapid Classification of Events (ALeRCE). In 2022, another outburst was observed, and over time the Zwicky Transient Facility (ZTF) found a pattern of outbursts every 60–90 days. It clearly wasn’t a supernova, but it was unclear on what it could be until a recent study solved the mystery.

One idea was that AT 2021hdr was a tidal disruption event (TDE),] where a star strays too close to a black hole and is ripped apart. This can create periodic bursts as the stellar remnant orbits the black hole, but TDEs don’t tend to have such regular patterns. So the team considered another model, where a massive interstellar cloud passes into the realm of a pair of binary black holes.

Simulations show how binary black holes interact with a gas cloud. Credit: F. Goicovic et al. 2016

Computer simulations show that rather than simply ripping apart the cloud, a binary black hole would churn the cloud as it consumes it. This would produce a periodic burst of light as the black holes orbit. The team observed AT 2021hdr using the Neil Gehrels Swift Observatory and found periodic oscillations of ultraviolet and X-ray light that match the transient bursts observed by ZTF. These observations match the simulations of a binary black hole.

Based on the data, the black holes have a combined mass of about 40 million Suns, and they orbit each other every 130 days. If they continue along their paths, the two black holes will merge in about 70,000 years. Without the passing cloud, we would have never noticed them.

The team plans to continue their observations of the system to further refine their model. They also plan to study how the black holes interact with their home galaxy.

Reference: L. Hernández-García, et al. “AT 2021hdr: A candidate tidal disruption of a gas cloud by a binary super massive black hole system.” Astronomy & Astrophysics 691 (2024)

The post Two Supermassive Black Holes on the Verge of a Merger appeared first on Universe Today.

Researchers have found that under certain conditions, a laser beam can act like an opaque object and cast a shadow, opening new possibilities for technologies that could use a laser beam to control another laser beam.

Researchers look to deep learning techniques in order to streamline the time-consuming process of identifying 2D materials.

Researchers look to deep learning techniques in order to streamline the time-consuming process of identifying 2D materials.

Researchers have developed robotic trousers that enable people to walk more easily while expending measurably less energy. The aim is to keep frail individuals and in particular the elderly mobile and healthy for longer.