Tag Archives: extraterrestrial

Unusual Elements in Supernova Explosions May Influence Extraterrestrial Life

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Supernova remnant Cassiopeia A

NASA/JPL-California Institute of Technology/O. Krauss (Steward Observatory)

Within Cassiopeia A, the youngest known supernova in our galaxy, scientists have uncovered unexpectedly high concentrations of chlorine and potassium. These elements, which possess an odd number of protons, are believed to be relatively rare in the universe but are crucial for the emergence of planets and life. Consequently, the findings regarding Cassiopeia A may influence our understanding of the potential locations for extraterrestrial life within the Milky Way.

Supernova remnants, or exploded stars, typically contain elevated levels of elements like oxygen and magnesium, with their cores being comprised of even-numbered protons. Elements with odd-numbered protons (often referred to as “odd Z” elements) are inherently less stable, leading to a reduced likelihood of being created via stellar nuclear fusion. This observation aligns with models of galactic chemical evolution that generally estimate meager quantities of odd Z elements.

“[As it stands] The source of these odd Z elements has been elusive.” Matsunagaumi from Kyoto University in Japan.

Matsunaga and his team recognized that high-resolution X-ray spectroscopy might shed light on the enigma. At the high temperatures prevalent in a supernova remnant, atoms lose electrons and emit unique X-ray signatures that sensitive instruments can detect. The X-ray Imaging Spectroscopy Mission (XRISM), launched in September 2023, is equipped to capture such data and conducted two observations of Cassiopeia A in December 2023.

To determine the abundance of each element, the researchers compared the faint signals from the odd Z elements against the stronger signals from even Z elements, like sulfur and argon, using them as stable reference points for more accurate measurements of the odd Z elements.

The findings revealed that the Cassiopeia A supernova generated significantly more chlorine and potassium than traditional models had anticipated. This indicates that theorists might need to reassess how large stars synthesize these uncommon elements, as certain widely accepted models fail to accommodate the specific conditions of Cassiopeia A.

“While the authors note that their observations diverge from previous models, the reality is more intricate,” says Stan Woosley of the University of California, Santa Cruz, who did not participate in the study. “Not all of our models are incorrect; some perform better than others, and certain ones correlate quite well. Importantly, these observations present astronomers with new, definitive data to refine their models and enhance our comprehension of massive stellar explosions.”

The recent measurements also empower Matsunaga and his colleagues to start evaluating various longstanding theories regarding the formation of odd Z elements in massive stars, including stellar rotation, interactions between binary star pairs, and the merging of diverse combustion layers deep inside stars. Up until now, there was no method to validate these theories against actual data.

“We still lack a complete understanding of which star types contributed to this,” states Katarina Rodders from Washington University in St. Louis, Missouri, who was not involved in the study. “Specifically, we lack clarity regarding the source of chlorine, an element abundant in our oceans.”

If these discoveries hold true for other supernova remnants, they could reshape our perceptions of how life-essential elements are distributed throughout the Milky Way. Depending on the star that seeded a planet, some areas may have a more favorable supply of life’s foundational materials than others. This raises the possibility of uneven distribution of extraterrestrial life across the galaxy.

“That is certainly a possibility,” Matsunaga remarked. “However, we cannot definitively assert this based on the current data.” It remains uncertain whether Cassiopeia A is singular in its production of such substantial quantities of odd Z elements or if it is indicative of supernova remnants in general. “Future observations of additional supernova remnants with XRISM and other upcoming instruments will be pivotal in addressing this issue.”

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Source: www.newscientist.com

Apologies, but interstellar visitor 3I/ATLAS is truly a comet, not an extraterrestrial.

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Interstellar comet 3I/ATLAS captured by the Gemini South Telescope in Chile

International Gemini Observatory/NOIRLab/NSF/AURA/Shadow the Scientist; J. Miller & M. Rodriguez (International Gemini Observatory/NSF NOIRLab), TA President (University of Alaska Anchorage/NSF NOIRLab), M. Zamani (NSF NOIRLab)

The interstellar object 3I/ATLAS is acting oddly once more. This foreign visitor from another star is now obscured by the sun’s shadow, leading some to speculate about its secretive nature. The only likely explanation, they whisper, is that it’s an alien spacecraft.

This notion, however, is utterly baseless. It simply doesn’t hold up that a spacecraft would choose to stay hidden for just a few days while previously visible and likely to be so again. If this were actually a stealthy spacecraft, then the aliens piloting it would either be incredibly foolish or believe us to be.

How can we assert this? As an astronomer recently explained to me, if 3I/ATLAS is indeed a spacecraft, it’s doing a remarkable job of masquerading as a comet. This is what fuels the sensational discussions surrounding 3I/ATLAS (named after the eagle’s eye). planetary defense equipment (I first noticed it in July), which was both amusingly frustrating and clearly ridiculous. The evidence overwhelmingly indicates that it is a comet.

Let’s explore why. It possesses a coma, a shell of vaporized ice. It exhibits a luminous tail. Its trajectory can best be described as that of an icy projectile entering our solar system from beyond. So, why is it “hiding” behind the sun? It just reached perihelion, the closest point to our solar star in its voyage through our cosmic neighborhood. Every celestial voyager, from comets to asteroids, experiences perihelion. 3I/ATLAS happens to be behind the Sun, yet closest to it from Earth’s viewpoint.

There are certainly some intriguing aspects of 3I/ATLAS that excite astronomers. For instance, it contains a higher concentration of carbon dioxide ice compared to water ice. Nevertheless, it remains a comet, not a space probe. Some materials are composed of – hold on, aren’t those metals? Spaceships are built from metal! So, could 3I/ATLAS actually be a spacecraft? Absolutely not; we routinely observe metals in the rocky, icy cores of comets. In truth, numerous comet types exist in our solar system, many of which are indeed peculiar.

It was also somewhat unusual that at one point 3I/ATLAS had its dusty tail oriented toward the Sun instead of the opposite direction. Some speculated it was not the tail but rather a spacecraft’s exhaust plume attempting to decelerate. However, the issue is that 3I/ATLAS’s orbit is consistent with that of an interstellar comet; it’s not as if someone applied brakes to an interstellar probe. The unique orientation of its tail resulted from the specific icy, powdery particles released from its surface. This transient object would typically be pushed away from the sun by solar radiation pressure, but some of this comet’s material was so dense that it couldn’t be redirected and consequently rolled toward the sun.

3I/ATLAS is only the third interstellar object ever documented, so investigating its small population is likely to uncover some remarkable characteristics. ‘Oumuamua, the first identified interstellar visitor, was significantly stranger. Its shape was likely cigar-like, rapidly accelerating as it left the solar system. Yet even this oddity can be perfectly rationalized: it was a flashy comet-like entity. The next two interstellar objects, 2I/Borisov and 3I/ATLAS, also showcase interesting features. But to propose they are spacecraft rather than comets is equivalent to calling ice in the freezer a pineapple. You can certainly say that, but if you aim to convince me, you must present more substantial proof.

Many among us, myself included, eagerly anticipate the day we learn we’re not alone in the universe. Thus, it’s no wonder that people jump to the unfounded conclusion that 3I/ATLAS might signal that this long-awaited day has finally come. However, in an age rife with misinformation, to suggest, against overwhelming evidence, that this comet could be alien is not just misguided; it’s profoundly irresponsible.

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Source: www.newscientist.com

Extraterrestrial Space Imagery from Noteworthy Photoshoot Competitions

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Encounter Within One Second ©Zhang Yanguang

The International Space Station (ISS) glides across the sun, with spectacular close-ups of comets and exotic trees amidst rotating stars all selected as contenders for this year’s ZWO Astronomical Photographer of the Year Contest.

The image above is from Zhang Yanguang titled Meet Within 1 Second: It features a series of silhouetted shots of the ISS as it passes directly between Earth and the Sun. The expansive solar panels on the spacecraft, collecting energy from the very same star, are vividly visible. The photographer utilized dual optical filters to isolate specific wavelengths, showcasing the sharp details of the sun’s surface.

Close-up of Comet C/2023 A3 ©Gerald Rhemann and Michael Jäger

The image above showcases a close-up of comet C/2023 A3 (Tsuchinshan-atlas) captured by Gerald Leman and Michael Jäger in Namibia. The comet displays two distinct tails of dust and gas, which appear to be nearly overlapping due to solar wind effects.

The last image presented is titled Dragon Tree Trail, taken by Benjamin Barakat in the Famihin forest on Socotra Island, Yemen. The iconic Dragon’s Blood Tree (Dracaena Cinnabari) stands prominently, framed by a stellar background crafted from 300 individual exposures.

Dragon Tree Trail ©Benjamin Barakat

This year’s competition saw more than 5,500 submissions from 69 nations. The top entries in nine categories, alongside two special awards and the overall victor, will be revealed on September 11th and displayed in an exhibition at London’s National Maritime Museum starting September 12th.

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Source: www.newscientist.com

A Saltwater Pool in an Underwater Volcano: Habitat for Extraterrestrial Life Forms?

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SEI 259096022

Creatures uncovered near the Mabahismon volcano in the Red Sea, such as amphipods and polychaete worms

Dr. Katrin Linse

Ultra-salty lakes rich in carbon dioxide can support extreme life forms that differ from those found in other environments.

Dense saline water, laden with minerals, sinks to the ocean floor, where it can pool in depressions, creating unique brine lakes distinct from the upper waters. These brine pools, identified in various oceans, feature a unique chemical makeup—low in oxygen yet rich in particular minerals—allowing extreme microorganisms to thrive and evolve.

Recently, Froukje van der Zwan from King Abdullah University of Science and Technology in Saudi Arabia and her team have identified a novel brine pool that is warm, carbon-rich, and possibly nourished by underwater volcanic activity.

On a recent expedition to two underwater volcanoes in the Red Sea, Haty Bamons and Mabahismons, Van der Zwan and her colleagues found several brine pools located near the summit of the volcano, about five kilometers from mineral deposits where salt concentration increases. They also discovered regions with numerous hydrothermal vents releasing mineral-rich water at temperatures around 60°C (140°F).

Using a robotic vehicle for sampling revealed that the pool was warmer than the surrounding water and exhibited elevated levels of metallic elements like zinc and manganese.

The hot water vents also contained rich gas. “They show relatively high CO2 levels, similar to methane… however, unlike other hot water vents where liquids mix with seawater, this might function as a trap for these gases, being sequestered in the salt water here.”

Researchers are currently examining microbial samples collected from these pools to understand how life adapts to such extreme environments. Nearby hydrothermal vents revealed thick mats and diverse lifeforms, including polychaete worms and amphipods, featuring microorganisms considerably larger than known marine counterparts.

Living within a saline pool may offer insights into how life might thrive in harsh extraterrestrial environments, such as the salty, iron-rich oceans beneath the icy crust of Jupiter’s moon Europa. If hydrothermal activities exist beneath this surface, it could present scenarios similar to the iron-rich brine pool discovered by Van der Zwan and her research team.

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Source: www.newscientist.com

Civilians and Military Radar Leakage Exposes Our Presence to Extraterrestrial Civilizations, Studies Indicate

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A recent study by researchers at the University of Manchester explored Earth’s radar systems as a potential technological signature detectable by extraterrestrial observers. While SETI typically emphasizes intentional transmissions, this study focused on the unintended electromagnetic emissions from civilian and military radar systems at airports. These technologies constitute vital components of advanced civilizations and produce radio emissions that can be identified across interstellar distances. The authors investigated how the global distribution of radar installations influences the temporal characteristics of Earth’s radio signatures as viewed from six specific star systems: Bernard Star, HD 40307, AU Microscope, HD 216520, and LHS 475. The results indicate that radar systems represent one of the most detectable and unintended technological signatures of advanced civilizations, paving the way for the possible detection of extraterrestrial intelligence.

Ramiro Saide et al. examined how extraterrestrial leaks are concealed from Earth up to 200 light-years away if they possessed a radio telescope similar to ours. Image credit: Gemini AI.

“Our investigation revealed that the airport radar systems, which manage air traffic, emit a staggering total of 2×1015 radio signals,” stated Ramilo Kais Said, a student at the University of Manchester.

“To provide context, the nearest potentially habitable exoplanet beyond our solar system is Proxima Centauri B, located four light-years away.”

“These signals will continue to reach spacecraft utilizing current technology for thousands of years.”

Military radar systems, which are more focused and directional, create unique emissions akin to lighthouse beams that illuminate specific fields of view.14

“To observers at interstellar distances with advanced radio telescopes, these emissions would obviously appear artificial,” remarked Kaisse Saide.

“Indeed, these military signals can appear up to 100 times more intense from a particular vantage point in the universe, contingent on the observer’s location.”

“Our findings indicate that radar signals unintentionally produced by any technologically advanced civilization with complex aviation systems could serve as a universal sign of intelligent life.”

This research not only guides the search for extraterrestrial civilizations by pinpointing promising technological signatures but also enhances our understanding of how human technology is perceived from space.

“Insights into how our signals propagate through space offer valuable lessons on safeguarding our radio spectrum for communication and designing future radar systems,” stated Professor Michael Garrett from the University of Manchester.

“The methods we developed for modeling and detecting these faint signals hold promise for applications in astronomy, planetary defense, and assessing the impacts of human technology on the space environment.”

“Thus, our work contributes to scientific endeavors addressing the question, ‘Are we alone?'” Kaisse Saide noted.

The researchers presented their results today at the National Astronomical Conference of the Royal Astronomical Society 2025 in Durham, England.

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Ramiro Saide et al. investigate airport civilian and military radar emissions as detectable markers for extraterrestrial civilizations. NAM 2025

Source: www.sci.news

Astronomers continue to debate the strongest evidence for extraterrestrial life

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Impressions of the artists of Planet K2-18B and its host star

ESA/Hubble, M. Kornmesser

Astronomers claim they have seen the most powerful evidence ever for living on another planet. However, other astronomers are cautioning until the findings are verified by other groups, allowing alternative, nonbiological explanations to be excluded.

“These are the first hints we see about the alien world we probably live in.” Nick Madhusdan We held a press conference at Cambridge University on March 15th.

Astronomers first discovered the Exoplanet K2-18B in 2015, quickly establishing it as a promising place for searching for life. Planets orbiting stars about eight times more than Earth, 124 light years away from us, sit in a habitable zone of stars where liquid water is present. Further observations in 2019 found evidence of water vapor. This led to the suggestion that, although not all astronomers agreed, the planet could be covered in oceans sitting under a hydrogen-rich atmosphere.

In 2023, Madhusudhan and his colleagues used James Webb Space Telescope (JWST) instruments to examine the atmosphere of the near-infrared light K2-18B, again finding evidence of water vapor and methane. However, they also found appetizing hints for dimethyl sulfide (DMS), a molecule that is produced exclusively by organisms on Earth, primarily by marine phytoplankton. However, the signs of DMS were very weak and many The astronomers argued Stronger evidence is needed to be certain about the existence of molecules.

Currently, Madhusudhan and his colleagues use different instruments to observe the K2-18b than the mid-infrared camera JWST. They discovered a much stronger signal against DMS and a molecule that could be called dimethyldisulfide (DMDS).

“What we’re finding is a line of independent evidence in different wavelength ranges with different equipment that can potentially biological activity on the planet,” Madhusdan said.

The team argues that detection of DMS and DMD is at three sigma levels of statistical significance. This corresponds to a 1/100 chance that a pattern of data like this will become absorption. In physics, the standard threshold for accepting something as a true discovery is five sigmas, which corresponds to 1-3.5 million chances that data is a coincidence.

Nicholas Wargan The NASA Ames Research Center in California says the evidence is more convincing than the 2023 results, but it should be verified by other groups. When data is published next week, other researchers can begin to review the findings, but this could take weeks or months as JWST data is difficult to interpret. “It’s not just about downloading data and checking if there’s a DMS. It’s this extremely complicated process,” says Wogan.

Other scientists are more skeptical of the findings. “These new JWST observations do not provide compelling evidence that DMS or DMD exists in the atmosphere of K2-18B.” Ryan McDonald At the University of Michigan. “We have a juvenile chase wolf situation in the K2-18B, where multiple previous 3-sigma detections have completely disappeared when subjected to closer scrutiny.

Madhusudhan and his team estimate that further 16 to 24 hours of further observations at the JWST will help reach 5-sigma levels, but observing the planet’s atmosphere means that this cannot be guaranteed.

“The relative size of the atmosphere compared to the planet’s size is pretty close to the thickness of the apple’s skin on top of the apple, which is what we’re trying to measure.” Thomas Beatty At the University of Wisconsin-Madison, where I was not part of the learning team. Wogan adds that reaching five sigmas may be fundamentally impossible due to the amount of noise in the data.

But if further observations prove that this is a real discovery, it would be a “risqué progress,” says Beatty. “Ignoring whether it was actually being produced for a moment, I said that ten years ago it is evidence of life in a planetary atmosphere that can certainly host it.”

Madhusudhan and his colleagues calculate that the potential concentration of DMS and DMD in K2-18B appears to be over ten parts, thousands of times more than the concentrations in the Earth’s atmosphere. This could show far more biological activity than Earth if the signal turns out to be correct, but establishing that chemicals have biological origins requires more work, he says.

“We need to be very careful,” Madhusdan said. “At this stage, when you detect DMS and DMD, you can’t claim it’s for life. Let’s be very clear about that.

It could take some time to eliminate another mechanism, Wogan says. “This kind of thing hasn’t been studied in practice. In a hydrogen-rich atmosphere, DM doesn’t know tons about it. It requires a lot of work.”

The difficulty in proving that it has no nonbiological explanations is that it could potentially put K2-18B in the category of viable biosignature candidates over a long period of time. Sarah Seager At Massachusetts Institute of Technology. “It could remain in that category for decades, because the problem will not be completely solved by providing limited data deplanets,” she says.

However, Madhusudhan says this discovery is important whether it comes from life or not. “This was a revolutionary moment, and we were able to come from a single cell life, not just as astronomers, but also for our species, from a single cell life billions of years ago, to a highly technological civilization where we could peer into the atmosphere of another planet and find evidence of actual biological activity,” he said.

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Research on the various cloud layers, temperature hot spots, and shifting chemistry found in the extraterrestrial realm

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New observations from the NASA/ESA/CSA James Webb Space Telescope support the presence of three specific functions in the atmosphere (clouds, hot spots, and changes in carbon chemistry) of the rapidly rotating and free floating planetary mass object SIMP J013656.5+093347.

Impressions of the artist of SIMP 0136. Image credits: NASA/ESA/CSA/J. Olmsted, Stsci.

SIMP J013656.5+093347 (SIMP 0136 for short) is a rapidly rotating, free-floating object located just 20 light years from Earth.

It may have a mass of 13 Jupiter masses, does not orbit the star, and instead may be a brown dwarf.

Because it is separated, SIMP 0136 can be directly observed and is not afraid of mild contamination or variability caused by the host star.

The short rotation period, only 2.4 hours, allows for very efficient investigation.

“We've been working hard to get into the world,” said Allison McCarthy, a doctoral student at Boston University.

“We also thought that it might have an effect on temperature fluctuations, chemical reactions, and perhaps the activity of the aurora affecting brightness, but we weren't sure.”

Webb's NirSpec Instruments We captured thousands to 5.3 micron spectra of SIMP 0136. The object completed one full rotation, so I captured it one at a time, one at a time, one at a time, one at a time, over 3 hours.

This led to immediate observation Webb's Milli Musical Instrumentshundreds of measurements of light between 5 and 14 microns were collected. One is one every 19.2 seconds, one in another rotation.

The results were hundreds of detailed rays, each showing a very accurate wavelength (color) brightness change, with different sides of the object rotating into view.

“It was incredible to see the entire range of this object change over a few minutes,” said Dr. Joanna Foss, an astronomer at Trinity College Dublin.

“Until now, we only had a small near-infrared spectrum from Hubble, but we had some brightness measurements from Spitzer.”

Astronomers almost immediately noticed that there were several distinct ray shapes.

At any time, some wavelengths were growing brightly, while others were either dimmed or not changing at all.

Many different factors must affect brightness variation.

“Imagine looking at the Earth from afar,” said Dr. Philip Muirhead, a former member of Boston University.

“Looking each color individually gives you a variety of patterns that tell you something about the surface and the atmosphere, even if you don't understand the individual features.”

“As the ocean rotates towards vision, blue increases. The brown and green changes tell us something about the soil and vegetation.”

To understand what could cause variability in SIMP 0136, the team used an atmospheric model to show where each wavelength of light is occurring in the atmosphere.

“The different wavelengths provide information about the different depths in the atmosphere,” McCarthy said.

“We began to realize that the wavelengths that had the most similar ray shapes also investigated the same depth and reinforced this idea that they must be caused by the same mechanism.”

For example, one group of wavelengths occurs deeply in the atmosphere where there may be patchy clouds made of iron particles.

The second group comes from high clouds, which are thought to be made from small grains of silicate minerals.

Both of these light curve variations are related to the patchiness of the cloud layers.

The third group of wavelengths appears to be occurring at very high altitudes far above the clouds and tracking temperatures.

Bright hotspots may be associated with previously detected auroras at radio wavelengths, or hot gas upwelling from deeper in the atmosphere.

Some light curves cannot be explained by clouds or temperature, but instead show variations related to atmospheric carbon chemistry.

There may be chemical reactions in which carbon monoxide and carbon dioxide pockets rotate within and outside of view, or alter the atmosphere.

“We still don't understand the chemical part of the puzzle yet,” Dr. Vos said.

“But these results are really exciting because they show that the richness of molecules like methane and carbon dioxide can change over time from location.”

“If you're looking at a deplanet and only have one measurement, you should assume that it may not be representative of the entire planet.”

Survey results It will be displayed in Astrophysics Journal Letter.

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Allison M. McCarthy et al. 2025. JWST weather report from isolated exoplanet analog SIMP 0136+0933: pressure-dependent variability driven by multiple mechanisms. apjl 981, L22; doi: 10.3847/2041-8213/AD9EAF

Source: www.sci.news

The Ideal Location of Our Milky Way Galaxy for Discovering Extraterrestrial Life

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CrackerClips Stock Media/Alamy

All life as we know it in the entire universe is tucked away on a tiny rock floating in a tiny branch of the Milky Way galaxy. There are billions of other planets that could potentially support life, but how does our location affect our chances of finding it?

So far, the search for life elsewhere has only scratched the surface. “The bubble of space we've been able to explore around the Sun is tiny compared to the size of our galaxy,” he said. Jesse Christiansen“But we've already discovered more than 5,000 planets, called exoplanets, that orbit other stars,” says John F. Kennedy, an astrophysicist at the California Institute of Technology. Some of these have been found throughout our galaxy and even in other galaxies, but most are within a few hundred light years of the sun, a stone's throw in the scheme of the universe.

Our Galactic Neighborhood

Astronomers are beginning to look at different types of stars in the galactic outskirts and how they affect the habitability of planets around them. We live in an arm of the Milky Way galaxy called Orion, inside the main plane of the galaxy called the thin disk. We are surrounded by stars in the Orion arm. Further outwards, we are surrounded by the dense bulge of the galaxy's dense core on one side, and the sparser outer parts of the other arms of the galaxy on the other side.

Thin, disk-shaped stars, like our Sun and other stars in the constellation Orion, generally…

Source: www.newscientist.com

Astronomers document extraterrestrial exoplanets

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The new catalogue, created as part of the TESS-Keck survey, includes 126 strange planets outside our solar system, ranging from unusual worlds with extreme environments to those that could potentially support life as we know it.

Artist's impression of the 126 planets in the new TESS-Keck survey catalog is based on data such as planet radius, mass, density, and temperature. Question marks represent planets that need more data for full characterization. Image courtesy of W. M. Keck Observatory/Adam Makarenko.

“Relatively few known exoplanets have had both their mass and radius measured,” said Steven Kane, professor at the University of California, Riverside, and principal investigator of the TESS-Keck survey. paper Published in Astrophysical Journal Supplement.

“Combined, these measurements tell us what the planet is made of and how it formed.”

“With this information, we will be able to answer the question of where our solar system fits in the grand scheme of other planetary systems.”

Professor Kane and his colleagues analysed more than 13,000 radial velocity (RV) measurements to calculate the masses of 120 confirmed planets and six candidate planets spread across the northern sky.

“These RV measurements allow astronomers to detect and characterize these exoplanetary systems,” said astrophysicist Ian Crossfield of the University of Kansas.

“When we see a star wobbling back and forth in a regular pattern, we can infer the presence of orbiting planets and measure their masses.”

Several planets discovered in the TESS-Keck survey stand out as touchstones for improving astronomers' understanding of the diverse ways planets form and evolve.

in Related Papers In Astronomical JournalAstronomers have announced the discovery of two new planets orbiting a sun-like star.

The first is a sub-Saturnian planet with a mass and radius intermediate between Neptune and Saturn.

“There's been some debate about whether sub-Saturn planets are truly rare or whether we're just bad at finding them,” said Michelle Hill, a graduate student at the University of California, Riverside.

“So planet TOI-1386b is an important addition to this planetary group.”

TOI-1386b takes just 26 days to orbit its star, while its neighbour, a planet with a mass similar to that of Saturn, takes 227 days to orbit the same star.

in Related ArticlesThe researchers described TOI-1437b, a planet about half the size of Neptune that orbits a sun-like star every 19 days.

“Planets smaller than Neptune and larger than Earth are the most common worlds in our galaxy, but they don't exist in our solar system,” said Daria Pidhorodetka, a graduate student at the University of California, Riverside.

“With each new discovery, we are reminded of how diverse the universe is, and that our place in it may be more unique than we can understand.”

The catalog also contains detailed descriptions of planets that, unlike the Sun, orbit extremely short distances around their stars.

One is so close to the orange dwarf that it completes an orbit in less than 12 hours.

“TOI-1798c orbits its star so quickly that a year on the planet lasts less than half an Earth day,” said Alex Polansky, a graduate student at the University of Kansas.

“Because these planets are so close to their stars, they are extremely hot and receive more than 3,000 times the radiation that Earth receives from the Sun.”

“Being in this extreme environment means that the planet is likely losing any atmosphere it may have originally formed.”

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Alex S. Polanski other2024. TESS-Keck Survey. XX. Uniform RV analysis of 15 new TESS planets and all survey targets. AppJS 272, 32; Source: 10.3847/1538-4365/ad4484

Michelle L. Hill other2024. TESS-Keck Survey. XIX. Warm transiting sub-Saturn-mass and non-transiting Saturn-mass planets orbiting solar analogues. AJ 167, 151; Source: 10.3847/1538-3881/ad2765

Daria Pidhorodetka other. 2024. TESS-Keck Survey. XXII. TOI-1437 in Near-Neptune Orbit. arXiv: 2405.12448

Source: www.sci.news

Lessons from Uninhabitable Venus: Exploring the Potential for Extraterrestrial Life

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Given the diversity and complexity of endogenous and extrinsic processes that contribute to the maintenance of habitable conditions over geological and biological timescales, it is unclear how rocky planets become habitable and their status. Fully understanding how it is maintained is a fundamental challenge for planetary scientists and astrobiologists. In the face of this challenge, it is essential to exploit the full range of atmospheric evolution data for rocky planets within the solar system. Although Venus represents an apparent fringe member of planetary habitability, its contribution to understanding the prevalence of long-term temperate surface conditions in large rocky worlds remains poorly recognized. Upcoming missions to Venus, including NASA's VERITAS and DAVINCI, and ESA's EnVision mission, will begin to crystallize this understanding.

Kane and Byrne describe Venus as an anchor point where planetary scientists can better understand the conditions that prevent life on exoplanets. Image credit: Kane & Byrne, doi: 10.1038/s41550-024-02228-5.

“We often assume that Earth is a model of habitability, but when we consider this planet in isolation, we don’t know where the boundaries and limits are. Venus gives us that. '' said Dr. Stephen Cain, an astrophysicist at the University of California, Riverside.

“Although they also feature a pressure cooker-like atmosphere that could flatten humans in an instant, Earth and Venus share some similarities.”

“They have roughly the same mass and radius. Given their proximity to the planet, it’s natural to wonder why Earth looked so different.”

Many scientists believe that solar flux, the amount of energy Venus receives from the sun, caused a runaway greenhouse effect that doomed Earth.

“If Earth receives 100% of the solar energy, Venus collects 191%. Many people think that’s why Venus looks different,” Dr. Kane said.

“But wait a minute. Venus doesn’t have a moon, but that gives Earth something like ocean tides and affects the amount of water here.”

In addition to some of the known differences, more NASA missions to Venus will also clarify some of the unknowns.

Planetary scientists have no idea how big its core is, how it arrived at its current relatively slow rotational speed, how its magnetic field has changed over time, or the chemistry of its lower atmosphere. i don’t know.

“Venus has no detectable magnetic field. That may be related to the size of its core,” Dr. Kane said.

“The size of the core also gives us information about how the planet cools. Earth has a mantle, and heat circulates through its core. What’s going on inside Venus? I don’t know.”

“The interior of a rocky planet also influences its atmosphere. That is the case for Earth, and our atmosphere is primarily the result of volcanic gas emissions.”

Schematic cross-section of Earth and Venus. Major internal and atmospheric components are shown to scale. Image credit: Kane & Byrne, doi: 10.1038/s41550-024-02228-5.

NASA is planning two missions to Venus (DAVINCI and VERITAS) for the end of this decade, and Dr. Cain is supporting both.

The DAVINCI mission will explore the acid-filled atmosphere and measure noble gases and other chemical elements.

“DAVINCI measures the atmosphere from top to bottom. This is extremely useful for building new climate models and predicting this type of atmosphere elsewhere, including on Earth, as the amount of carbon dioxide continues to increase. ,” Dr. Kane said.

Although the Veritas mission will not land on the surface, it will allow scientists to reconstruct detailed 3D terrain, which could reveal whether the planet has active plate tectonics or volcanoes.

“Currently, our global map is very incomplete. Understanding how active a surface is and understanding how it has changed over time are very different. We need both types of information,” Dr. Kane said.

Ultimately, Dr. Kane and his co-author, Dr. Paul Byrne of Washington University in St. Louis, advocate such a mission to Venus for two main reasons.

One is that with better data, we can use Venus to confirm that our inferences about life on distant planets are correct.

“The somber thing about searching for life elsewhere in the universe is that we will never have in-situ data on exoplanets. We will never go there, land on them, or measure them directly. I don’t intend to,” Dr. Kane said.

“If we think there is life on the surface of another planet, we may never realize we are wrong and end up dreaming of a planet without life.” I guess.”

“We can only get it right by understanding the Earth-sized planets we can visit. Venus gives us that chance.”

Another reason to study Venus is that it can predict what Earth’s future will be.

“One of the main reasons we study Venus is because of our sacred duty as stewards of this planet to protect its future,” Dr. Kane said.

“My hope is that by studying how Venus came to be today, we can learn lessons from it, especially if it had a benign past that is now in ruins. The question is when and how.”

of review paper It was published in the magazine natural astronomy.

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Stephen R. Cain and Paul K. Byrne. 2024. Venus as an anchor point for planetary habitability. Nat Astron 8, 417-424; doi: 10.1038/s41550-024-02228-5

Source: www.sci.news

Possible discovery of extraterrestrial aurora on a neighboring collapsed star

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Brown dwarfs, often referred to as “failed stars,” are a fascinating type of celestial object. They are too large to be considered planets, yet too small to undergo the fusion process necessary to become fully-fledged stars.

One such brown dwarf, named WISEP J193518.59–154620.3 (or W1935 for short), is believed to be observable from Earth, especially towards the north and south poles. Astronomers suspect that it may exhibit an aurora similar to the mesmerizing aurora borealis, but on a much brighter scale.

Research featured in the journal Nature utilized NASA’s James Webb Space Telescope (JWST) to study W1935. This brown dwarf is relatively close to us in the galaxy, approximately 47 light-years away from Earth.

Upon pointing a space telescope the size of a tennis court towards the brown dwarf, researchers noticed a peculiar glow emanating from it.

“We were expecting to detect methane as it’s abundant in these brown dwarfs. However, instead of absorbing light, we found methane emitting light,” stated Dr. Jackie Faherty, the lead author of the study. “My initial reaction was, ‘What’s going on? Why is this object emitting methane?'”

Co-author Dr. Ben Burningham mentioned to BBC Science Focus that in the search for alien auroras in objects like W1935, astronomers traditionally focused on emissions from other gases found higher up in the object’s atmosphere.

“Methane emissions were not anticipated to be significant, but now it appears to be a significant factor,” he added.

Computer modeling of W1935 to elucidate the unusual methane emissions revealed a surprising temperature inversion, where the atmosphere gets warmer with increasing altitude. This phenomenon is common for planets orbiting stars but unexpected for an isolated object like W1935 without an apparent external heat source.

Further investigation led researchers to compare W1935 with Jupiter and Saturn from our solar system, which also exhibit methane emissions and temperature inversions.

The observed features in the solar system giants are attributed to auroras, luminous phenomena generated when energetic particles interact with the planet’s magnetic field and atmosphere.

Auroras are known to heat the upper atmosphere of planets, aligning with the researchers’ findings regarding W1935.

However, a missing element in the puzzle was the source of particles causing high-energy auroras in our solar system, which stem from the sun and travel as solar wind. Since W1935 is a rogue star without a host star, solar wind was ruled out as a possible explanation.

Scientists hypothesize that an undiscovered active satellite could be generating the alien aurora observed in W1935, akin to moons around Jupiter and Saturn that expel material into space enhancing the gas giants’ auroras.

“W1935 presents an intriguing expansion of solar system phenomena without any stellar illumination to clarify it,” Faherty remarked. “With Webb, we can delve into the chemistry and unravel the similarities or differences in auroral processes beyond our solar system.”

About our experts

Jackie Faherty is a senior scientist and education manager at the American Museum of Natural History, focusing on detecting and characterizing brown dwarfs and exoplanets. She advocates for increasing diversity in STEM fields through her unique outreach efforts.

Ben Burningham is an Associate Professor and Head of Outreach at the University of Hertfordshire, specializing in brown dwarfs, substellar objects, and superplanets. Burningham has contributed to research published in the Astrophysical Journal, Nature, and Astronomical Journal.

Read more:

Source: www.sciencefocus.com

Europa Clipper: NASA’s Mission to Jupiter’s Moons Explores Possibility of Extraterrestrial Life

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Artist’s impression of the European Clipper near its namesake moon

NASA

Instruments aboard a NASA spacecraft scheduled to launch to Europe later this year could directly detect cellular material ejected from Jupiter’s icy moons, increasing the chances of finding life.

Europa is of scientific interest because researchers believe there is a vast saltwater ocean beneath its thick icy shell. It is also surrounded by an orbiting blanket of ice grains and dust, believed to be the remains of material kicked up after the meteorite struck.

NASA’s Europa Clipper spacecraft was launched in October and is scheduled to arrive at its destination in 2030, flying close to the moon but not landing on it. Ten experiments will be carried out aimed at studying Europa’s internal structure, including its ocean chemistry and potential habitability for extraterrestrial life.

One of these is the SUrface Dust Analyzer (SUDA), a type of instrument known as a mass spectrometer. The mission will collect material ejected from the moon and reveal its chemical composition, including potential organic molecules and salts.

SUDA was not designed to look for signs of life in Europe, but now Frank Postberg and his colleagues at Germany’s Freie Universität Berlin, who are working on the device, have shown that it can detect fragments of cellular material, potentially providing evidence of modern life.

“If life on Europa follows the same principle of having membranes and DNA made from amino acids… [those chemicals] “It will be the deciding blow of my life,” he says.

“This is an interesting result because these ice grains hit the instruments in space at speeds of 4 to 6 kilometers per second,” say team members. Fabian Krenner at the University of Washington. “We showed that we can still identify cellular material.”

These extreme velocities cause particles to collide with SUDA with high kinetic energy, breaking large molecular structures into smaller component parts for analysis. To simulate this kinetic energy, the team shot water droplets with a laser. I put the following sample into water. Sphingopyxis alascensisa bacterium known to survive in frigid marine environments, making it a potential alternative to life on Europa.

When the laser hits the droplet, it breaks up into tiny droplets that hit the SUDA detector. The researchers discovered that they could distinguish between fragmented cellular material, including fatty acids and amino acids, which are abundant in cell membranes.

“We have now simulated the presence of cells inside a single ice grain without any pretreatment, which may be a valid case for what we see in Europe,” Klenner said. To tell. The next step, he says, is to repeat the experiment using different types of cell cultures.

Murti Gudipati He works on SUDA at NASA’s Jet Propulsion Laboratory in Pasadena, Calif., but is not involved in the research. The results should reflect what could happen to the spacecraft, he said. Watch while on duty.

But the ability to clearly distinguish cellular material from other organic molecules and salts depends on the specific composition of the ice grains released from Europa, he says. If SUDA detects many other complex organic molecules and salts mixed in with the ice grains, it may be difficult for researchers to reliably detect cellular material, Gudipati says.

the current, NASA says When asked, “Europa Clipper is not a life-detecting mission. Its primary science goal is to determine whether there is a place beneath Europa’s surface where life could exist.” new scientist The agency was unable to respond prior to publication about whether the new research changes the mission’s goals.

topic:

Source: www.newscientist.com

The Search for Extraterrestrial Life: A Comprehensive Guide to Everything You Need to Know about Extraterrestrials

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Currently, there is a high level of excitement in the quest for extraterrestrial life. This field, known as astrobiology, combines biology, chemistry, planetary science, and astronomy to explore the possibility of life beyond Earth.

While microbial life forms like bacteria are expected to be the most common in the Milky Way, there is a chance that some planets could support more complex life forms such as plants and animals. Recent advancements in extremophiles, exoplanets, and robotic exploration have increased optimism among astrobiologists for discovering signs of life beyond Earth.

List three reasons why astrobiologists are optimistic about finding extraterrestrial life.

1. Extremophile microorganisms

The adaptability of life on Earth, especially extremophiles, showcases the limits of life in extreme environments. These microorganisms thrive in harsh conditions like hydrothermal vents, glaciers, acidic volcanic water, and high radiation zones, offering insights into potential habitable extraterrestrial environments.

Image credit: Getty

2. Exoplanets

Discovery of exoplanets orbiting distant stars has expanded the search for potentially habitable worlds. Small, rocky, Earth-like planets orbiting within the habitable zone of their stars offer promising locations for extraterrestrial life. Future space telescopes are expected to detect biosignatures, such as oxygen, indicating potential life forms.

3. Exploration of the solar system by robots

Advances in robotic technology have enabled probes to explore planets and moons in our solar system, revealing environments that could support life. From Mars to Europa and Enceladus, these missions provide valuable data on habitable conditions and the possibility of extraterrestrial life.

Where in the solar system could extraterrestrial life exist?

Various celestial bodies within our solar system, including Venus, Mars, Europa, Enceladus, and Titan, offer potential environments for extraterrestrial life. Whether in subsurface oceans or unique atmospheres, these locations raise interesting questions about the existence of life beyond Earth.

Do aliens have intelligence?

While astrobiology primarily focuses on single-celled life and biosignatures, the possibility of more complex life forms and intelligent beings in the galaxy is still an intriguing topic. Despite efforts to detect signs of intelligent life, no definitive evidence has been found yet.

Image credit: Getty

Source: www.sciencefocus.com

Scientists use innovative method to hunt for signs of extraterrestrial technology

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techno signature Any measurable property that could provide evidence of extraterrestrial technology. The Search for Extraterrestrial Intelligence (SETI) is a branch of astrobiology that focuses on the discovery of technosignatures, which provide evidence of extraterrestrial intelligence. Traditionally, targeted wireless surveys have been the mainstay of his SETI research, and many of his ongoing SETI projects are still conducted in the radio band. SETI Ellipsoid, a newly proposed technology, suggests that an extraterrestrial civilization observing a galactic-scale event such as supernova SN 1987A could use it as a point to broadcast a synchronization signal indicating its presence. This is a strategy for selecting techno signature candidates based on the assumption that .

Gaia Early Data Release 3, using Cabrales' improved star 3D positions other. identified 32 SN 1987A SETI ellipsoidal targets with uncertainties better than 0.5 light-years within the TESS continuum. Image credits: ALMA/ESO/NAOJ/NRAO/Alexandra Angelich, NRAO/AUI/NSF.

Barbara Cabrales, Ph.D., of the SETI Institute and the Berkeley SETI Research Center at the University of California, Berkeley, and her colleagues demonstrate that the SETI ellipsoid method leverages continuous, wide-field surveys of the sky and demonstrates its ability to detect potential technosignatures. We have shown that it can be significantly improved.

By using up to a year of observations to correct for uncertainties in the estimated time of arrival of such signals, we implement the SETI ellipsoid strategy in an innovative way using state-of-the-art technology.

“The new survey of the sky provides a groundbreaking opportunity to search for technosignatures in concert with supernovae,” Dr. Cabrales said.

“Typical timing uncertainty takes months, so we want to cover the bases by finding well-documented goals over about a year.”

“In addition to that, it's important to make as many observations as possible about each target of interest, so you can see what looks like normal behavior and what looks like potential techno-signatures.” You will be able to judge.”

In examining data from the Continuous Display Zone of NASA's TESS mission, which covers 5% of all TESS data during the first three years of the mission, the authors leveraged advanced 3D position data from Gaia Early Data Release 3. Did.

This analysis identified 32 major targets within the SETI ellipsoid in the southern part of the TESS continuum, with all uncertainties adjusted to better than 0.5 light-years.

Although initial inspection of TESS light curves during ellipsoid-crossing events did not find any anomalies, the foundation laid by this effort lends itself to other investigations, a broader range of targets, and a variety of potential signal types. Paving the way for expansion into research.

Applying SETI Ellipsoid technology to scour large archival databases represents a breakthrough in the search for technosignatures.

This study demonstrates the feasibility of leveraging Gaia's highly accurate distance estimates and cross-matching these distances with other time-domain surveys such as TESS to enhance monitoring and anomaly detection capabilities in SETI research. doing.

Combining the SETI Ellipsoid method with Gaia's distance measurements provides a robust and adaptable framework for future SETI searches.

Astronomers can apply it retrospectively to sift through archived data for potential signals, proactively select targets, and schedule future monitoring campaigns.

“The SETI Ellipsoid method, in collaboration with Gaia distances, provides an easy and flexible method for SETI searches that can be adapted to suit a variety of current surveys and source events,” the researchers said. I am.

“This can not only be applied retrospectively to look for signals in archived data, but also propagated in time to select targets and schedule surveillance campaigns.”

Their paper will appear in astronomy magazine.

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Barbara Cabrales other. 2024. Find the SN 1987A SETI ellipsoid using TESS. A.J. 167, 101; doi: 10.3847/1538-3881/ad2064

Source: www.sci.news

Unknown source of ultra-high energy extraterrestrial particle detected by telescope array

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An artist’s illustration of an extremely high-energy cosmic ray, named the “Amaterasu particle,” observed by the surface detector array of the Telescope Array experiment.Credit: Osaka Metropolitan University/L-INSIGHT, Kyoto University/Ryuunosuke Takeshige

A groundbreaking detection of extremely high-energy cosmic rays by a telescope array experiment points to a void in the universe and casts doubt on current theories about the origin and high-energy physics of cosmic rays. It raises questions about its source.

Discovery of an exceptional extraterrestrial particle

Researchers involved in the telescope array experiment announced that they had detected cosmic rays with unusual energy. This particle originates outside our galaxy and has an incredible energy level of more than 240 exaelectronvolts (EeV). Despite this remarkable discovery, its exact source remains elusive, as its direction of arrival does not point to any known celestial body.

The mystery of ultra-high energy cosmic rays

Cosmic rays are subatomic charged particles that come from space, and ultra-high energy cosmic rays (UHECRs) are a rare and extremely powerful type. These UHECRs have energies in excess of 1 EeV, which is about a million times the energy reached by man-made particle accelerators. These are thought to originate from the most energetic phenomena in the universe, such as black holes, gamma-ray bursts, and active galactic nuclei. However, its exact physics and acceleration mechanisms are still not fully understood. These high-energy cosmic rays occur infrequently, estimated at less than one particle per square kilometer per century, making their detection a rare event and requiring instruments with large collection areas. .

An artist’s illustration of ultra-high energy cosmic ray astronomy, which elucidates highly energetic phenomena as opposed to weak cosmic rays that are affected by electromagnetic fields.Credit: Osaka Metropolitan University/Kyoto University/Ryuunosuke Takeshige

A unique discovery of telescope arrays

The Telescope Array (TA) experiment, a large-scale surface detector array in Utah with an effective detection area of ​​700 square kilometers, successfully detected UHECR on May 27, 2021 at a breakthrough energy of approximately 244 EeV.

Given the very high energy of this particle, it should experience only a relatively small deflection by the foreground magnetic field, and therefore its direction of arrival should be expected to be more closely correlated with its source. Researchers point out that there is. However, our results show that the direction of arrival does not indicate an obvious source galaxy or other known objects that could be potential sources of UHECRs.

Instead, its direction of arrival points to a cavity in the large-scale structure of the universe, a region where galaxies are almost absent. Scientists believe this indicates a much larger magnetic deflection than predicted by galactic magnetic field models, an unidentified source in the local extragalactic neighborhood, or an incomplete understanding of the high-energy particle physics involved. This suggests that there is a possibility that

For more information on this discovery, see:

Reference: “Extremely high-energy cosmic rays observed by surface detector arrays”*†, RU Abbasi, MG Allen, R. Arimura, JW Belz, DR Bergman, SA Blake, BK Shin, IJ Buckland, BG Cheon, Tetsuya Fujii, Kazuya Fujisue, Kazuya Fujita, Masaki Fukushima, GD Furlich, ZR Gerber, N. Globus, Kazuto Hibino, Tatsuya Higuchi, Kazuya Honda, Daisho Ikeda, Hiroshi Ito, Akira Iwasaki, S. Jeong, HM Jeong, CH Jui, K. Kadota, F. Kakimoto, OE Kalashev, K. Kasahara, K. Kawata, I. Kharuk, E. Kido, SW Kim, HB Kim, JH Kim, JH Kim, I. Komae, Y. Kubota, MY Kuznetsov, KH Lee, BK Rubsandrjiev, JP Lundquist, JN Matthews, S. Nagataki, T. nakamara, A. Nakazawa, T. Nonaka, S. Ogio, M. Ono, H. Oshima, IH Park. , M. Potts, S. Pushilkov, JR Remington, DC Rodriguez, C. Lott, GI Rubtsov, D. Liu, H. Sagawa, N. Sakaki, T. Sako, N. Sakurai, H. Shin, JD Smith, P Sokolsky, BT Stokes, TS Stroman, K. Takahashi, M. Takeda, A. Takeda, Y. Tameda, S. Thomas, GB Thomson, PG Tyniakov, I. Tkachev, T. Tomita, SV Troitsky, Y. Tsunesada, S. Udo, FR Urban, T. Wong, K. Yamazaki, Y. Yuma, YV Zeser, Z. Zunder, November 23, 2023. science.
DOI: 10.1126/science.abo5095

Source: scitechdaily.com