Latest news with #astrobiology
Gizmodo
3 days ago
- Science
- Gizmodo
Titan's Methane Lakes Could Form Bubble-Like Structures Essential to Life, Scientists Say
On December 25, 2004, the Huygens probe separated from the Cassini spacecraft and landed on Titan's sandy surface. The probe survived for 72 hours on Saturn's largest moon, revealing a world that is chemically complex and more Earth-like than expected. For years, scientists have been intrigued by Titan as an alien world that might have the right conditions to host life, albeit in a very different form than on Earth. New research by NASA reveals that molecular precursors to life could form in Titan's methane lakes, allowing us a chance to learn how life originates and evolves in the universe. In a recently published paper in the International Journal of Astrobiology, a team of NASA researchers illustrates how vesicles, small, membrane-bound bubble-like compartments or sacs, could form naturally in the lakes of Titan. Vesicles are thought to play a vital role in the formation of life, an important step in making the precursors of living cells. The paper examines how the conditions for life could evolve in a vastly different environment than Earth, shedding light on our search for extraterrestrial life in the universe. Titan is the only other world, apart from Earth, that's known to have liquid on its surface. But unlike Earth's bodies of water, Titan's lakes and seas are not recommended for swimming, as they contain liquid hydrocarbons like ethane and methane. Water is crucial to life as we know it—but what if Titan's lakes have what it takes to harbor molecules required for life to evolve? The paper outlines a process by which stable vesicles might form on Titan based on the data that's been gathered so far about the moon's atmosphere and chemistry. On Earth, molecules known as amphiphiles have a split personality, with a hydrophobic (water-fearing) end and a hydrophilic (water-loving) end. When in water, the molecules naturally organize into ball-like spheres, resembling soap bubbles, whereby the hydrophilic part faces outward to interact with the water while its hydrophobic counterpart shies away on the inside of the sphere. This allows the molecules to form complex structures and may have led to primitive cell membranes in early Earth. On Titan, these vesicles could form thanks to the moon's complex meteorological cycle, according to the paper. The methane in Titan's atmosphere forms clouds, which rain on the surface to create river channels that fill up the moon's lakes and seas. The liquid on the surface then evaporates to form clouds once again. The researchers behind the new study suggest that spray droplets from the rain and the surface of the sea could be coated in layers of amphiphiles. When the droplets land on the surface of a pond, the two layers of amphiphiles meet to form a double-layered vesicle. Over time, the vesicles would be dispersed throughout the pond and would compete in an evolutionary process that could lead to the formation of primitive protocells. 'The existence of any vesicles on Titan would demonstrate an increase in order and complexity, which are conditions necessary for the origin of life,' Conor Nixon, a researcher at NASA's Goddard Space Flight Center and co-author of the new study, said in a statement. 'We're excited about these new ideas because they can open up new directions in Titan research and may change how we search for life on Titan in the future.' NASA is preparing to launch Dragonfly, the agency's first Titan mission, in July 2028. The rotorcraft lander will explore the surface of Saturn's moon and gather data about its atmosphere and geology. Dragonfly will help scientists better understand the bizarre world where life could form under vastly different conditions.
Forbes
10-07-2025
- Science
- Forbes
NASA Budget Cuts Could Have A Martian Silver Lining
With its active volcanism, Iceland is often used as a stand in for the surface of Mars. Bruce Dorminey Iceland is an astrobiologist's dream — rife with active volcanic landscapes, basaltic plains and lava tunnels that has repeatedly been used by NASA as a stand in for Mars. But at last week's European Astrobiology Institute's BEACON 25 conference in Reykjavik, most attendees were clamoring to get their hands on samples of the real thing. NASA's Perseverance rover — now perched on the rim of Jezero Crater in Mars' southern highlands, has collected some 41 subsurface samples just waiting for a sample return mission to retrieve them back to Earth. But that doesn't seem likely to happen anytime soon. Yet at least one planetary scientist refuses to be hamstrung by focusing on the funding hole in the Martian sample return donut. That's because even if there's a decades-long delay in getting the samples back to Earth, Perseverance's Radioisotope Thermoelectric Generator has plenty of life left and can potentially use the time to explore beyond Jezero Crater's rim. Perseverance has dropped samples on the crater floor, but it has more samples now from the rim in its storage cache, Adomas Valantinas, a Brown University planetary scientist, tells me in Reykjavik. But it would have to return back to the crater floor, where the lander from the Mars sample return mission would touch down, because it's flat and is a good area for landing with no strong winds, he says. Thus, in what could be a bit of serendipity, if the sample return is postponed indefinitely, Perseverance is free to roam beyond the rim of Jezero Crater. Why beyond the rim? Beyond the crater rim, there is this area called Nili Planum, a flat terrain that contains a lot of volcanic minerals, says Valantinas. If you go 30 to 50 km south, also beyond the rim in the northeast Syrtis region there are a lot of minerals that could have been formed by hydrothermal activity, he says. So, going south beyond the rim, you also have rocks that are potentially 4.1-billion-years-old where the potential for a habitable environment was even greater, says Valantinas. As noted in his Reykjavik presentation, Valantinas and colleagues' findings have specifically been researching the 3.8-billion-year-old, 45-km-wide Jezero impact crater. The Jezero impactor hit about the same time that life first formed on Earth and when liquid water was stable on the Martian surface. We used observations from NASA's Mars Reconnaissance Orbiter to understand the composition of the Jezero Crater rim, and we also did numerical simulations to understand how materials moved post impact and where they were deposited, says Valantinas. Ancient Rocks Our study basically shows that the materials in the Jezero rim are diverse, and they may represent a habitable environment 3.8 billion years ago, because they not only contain primary minerals, but secondary alteration minerals when liquid water was present, says Valantinas. Why is geological diversity important? Diversity probably means more complex mineralogy and more complex chemistry, which could mean a more habitable environment, says Valantinas. If we were seeing the same three or four different minerals and no diversity in the composition, that would probably mean it wasn't a habitable environment, he says. What kind of atmosphere did Mars have when the Jezero impactor hit? The atmosphere was probably thick enough for liquid water to exist on the surface, says Valantinas. So, it probably had some nitrogen, carbon dioxide and probably some water vapor, he says. Perseverance has already found some of the oldest rocks ever sampled on the Martian surface. But we need to push the envelope of what we really understand about the history of the red planet, which has both frustrated and perplexed even its most ardent advocates. That's why retrieving these samples for analysis in the best labs the world has to offer is so crucial to humanity's understanding of solar system science. Icelandic landscape near the boundary between the North American and Eurasian tectonic plates. Bruce Dorminey Radiation Threat There's also the potential that a decades-long delay in retrieving the samples that the Perseverance rover has collected could be affected by incoming cosmic radiation. Most of the samples are now safely positioned inside the rover but there are others that have been left on the surface near the landing site of a future sample return mission. The idea being that if for whatever reason, the rover malfunctions and can't make it back to the Jezero Crater basin, there would still be a few samples prepositioned on the surface which a return lander could retrieve for the journey back to Earth. Perseverance collected the samples themselves using a coring mechanism to a depth of only about 7 cm in depth. But now these sample cores are above ground they are much more susceptible to the effects of surface radiation. Even at 7 cm of subsurface depth, you must think about corpuscular (subatomic particle) radiation and galactic radiation, which is also bombarding the surface, Jean-Pierre De Vera, a planetary scientist at the German Aerospace Center (DLR), tells me in Reykjavik. And after several years inside the rover on the surface, the samples' original subsurface organics could certainly be changed, says De Vera. I'll be in the Icelandic Highlands for a week sampling iron oxide minerals in every kind of environment, from cold springs to hot springs and rivers, says Valantinas. The idea is to use Iceland as an analog for processes that could have happened on ancient Mars, he says. Why is Iceland better than anywhere else? Iceland is a volcanic island with basalt as a kind of the bedrock material, says Valantinas. So, the weathering of the basalts leads to secondary minerals in Iceland, and similar secondary minerals are observed on Mars, he says. Meanwhile, astrobiologists worldwide are hoping that the Mars samples can find their way back to Earth in a timely manner. As for why the Mars is so important to astrobiology? We're busy looking for life on exoplanets and we have Mars here that's within reach, Benton Clark, senior research geochemist at the Space Science Institute in Boulder, Colo. tells me in Reykjavik. All we need to do is to bring those samples back and we're going to learn so much more; maybe detect evidence of life, says Clark. Forbes Why Europe May Beat NASA To Life On Mars By Bruce Dorminey Forbes How NASA Can Avoid A False Positive Mars Microfossil Detection By Bruce Dorminey
Yahoo
29-06-2025
- Science
- Yahoo
Is the bar higher for scientific claims of alien life?
When you buy through links on our articles, Future and its syndication partners may earn a commission. The search for extraterrestrial life has long gone back and forth between scientific curiosity, public fascination and outright skepticism. Recently, scientists claimed the 'strongest evidence' of life on a distant exoplanet – a world outside our solar system. Grandiose headlines often promise proof that we are not alone, but scientists remain cautious. Is this caution unique to the field of astrobiology? In truth, major scientific breakthroughs are rarely accepted quickly. Newton's laws of motion and gravity, Wegener's theory of plate tectonics, and human-made climate change all faced prolonged scrutiny before achieving consensus. But does the nature of the search for extraterrestrial life mean that extraordinary claims require even more extraordinary evidence? We've seen groundbreaking evidence in this search beforehand, from claims of biosignatures (potential signs of life) in Venus's atmosphere to NASA rovers finding 'leopard spots' – a potential sign of past microbial activity – in a Martian rock. Both stories generated a public buzz around the idea that we might be one step closer to finding alien life. But on further inspection, abiotic (non-biological) processes or false detection became more likely explanations. In the case of the exoplanet, K2-18 b, scientists working with data from the James Webb Space Telescope (JWST) announced the detection of gases in the planet's atmosphere – methane, carbon dioxide, and more importantly, two compounds called dimethyl sulphide (DMS) and dimethyl disulphide (DMDS). As far as we know, on Earth, DMS/DMDS are produced exclusively by living organisms. Their presence, if accurately confirmed in abundance, would suggest microbial life. The researchers even suggest there's a 99.4% probability that the detection of these compounds wasn't a fluke – a figure that, with repeat observations, could reach the gold standard for statistical certainty in the sciences. This is a figure known as five sigma, which equates to about a one in a million chance that the findings are a fluke. So why hasn't the scientific community declared this the discovery of alien life? The answer lies in the difference between detection and attribution, and in the nature of evidence itself. JWST doesn't directly 'see' molecules. Instead, it measures the way that light passes through or bounces off a planet's atmosphere. Different molecules absorb light in different ways, and by analysing these absorption patterns – called spectra – scientists infer what chemicals are likely to be present. This is an impressive and sophisticated method – but also an imperfect one. It relies on complex models that assume we understand the biological reactions and atmospheric conditions of a planet 120 light years away. The spectra suggesting the existence of DMS/DMDS may be detected because you cannot explain the spectrum without the molecule you've predicted, but it could also result from an undiscovered or misunderstood molecule instead. Given how momentous the conclusive discovery of extraterrestrial life would be, these assumptions mean that many scientists err on the side of caution. But is this the same for other kinds of science? Let's compare with another scientific breakthrough: the detection and attribution of human-made climate change. The relationship between temperature and increases in CO₂ was first observed by the Swedish scientist Svante Arrhenius in 1927. It was only taken seriously once we began to routinely measure temperature increases. But our atmosphere has many processes that feed CO₂ in and out, many of which are natural. So the relationship between atmospheric CO₂ and temperature may have been validated, but the attribution still needed to follow. Carbon has three so-called flavors, known as isotopes. One of these isotopes, carbon-14, is radioactive and decays slowly. When scientists observed an increase in atmospheric carbon dioxide but a low volume of carbon-14, they could deduce that the carbon was very old – too old to have any carbon-14. Fossil fuels – coal, oil and natural gas – are composed of ancient carbon and thus are devoid of carbon-14. So the attribution of anthropogenic climate change was proven beyond reasonable doubt, with 97% acceptance among scientists. In the search for extraterrestrial life, much like climate change, there is a detection and attribution phase, which requires the robust testing of hypotheses and also rigorous scrutiny. In the case of climate change, we had in situ observations from many sources. This means roughly that we could observe these sources close up. The search for extraterrestrial life relies on repeated observations from the same sensors that are far away. In such situations, systematic errors are more costly. Further to this, both the chemistry of atmospheric climate change and fossil fuel emissions were validated with atmospheric tests under lab conditions from 1927 onwards. Much of the data we see touted as evidence for extraterrestrial life comes from light years away, via one instrument, and without any in situ samples. The search for extraterrestrial life is not held to a higher standard of scientific rigor but it is constrained by an inability to independently detect and attribute multiple lines of evidence. For now, the claims about K2-18 b remain compelling but inconclusive. That doesn't mean we aren't making progress. Each new observation adds to a growing body of knowledge about the universe and our place in it. The search continues – not because we're too cautious, but because we are rightly so. This article is republished from The Conversation under a Creative Commons license. Read the original article.
CBC
03-06-2025
- Health
- CBC
What does space smell like? This perfume-making astrobiologist is trying to find out
After a long career of creating designer perfumes, Marina Barcenilla decided to turn her nose to the cosmos. The fragrance designer enrolled in university in 2015 to study planetary science. She was taking classes in astrochemistry — the chemical makeup of outer space — when she realized she could marry her two passions. "Whenever I see something new, the first question is: I wonder what that smells like," she told As It Happens host Nil Köksal. "One day I thought: Actually, this molecule that I'm studying? I have it in my perfume lab. And this smell that I am imagining? I could actually create it." Barcenilla is now an astrobiology doctoral researcher at the University of Westminster in London, England. When she's not exploring the feasibility of life on Mars, she's recreating the smells of space, from the sulfuric stench of Jupiter's deepest clouds, to the pungent alcohol-like punch at the centre of the Milky Way. Four of those stellar scents are now available for public sniffing at the London Natural History Museum, as part of the ongoing exhibit: Space: Could life exist beyond Earth? 'Antiseptic,' but also like gunpowder? So what does space smell like? "I don't think it smells very good in general," said Barcenilla. Those in the know can attest. Canadian astronaut Julie Payette, upon returning from the International Space Station, told CBC News in 2009 that space smells "cold" and "antiseptic." "I opened the hatch six hours after the space walk. This entire airlock area had been exposed to the vacuum of space for all those hours. So when I opened the door, I smelled what was kind of an antiseptic smell," she said. "It was not detergent but it was definitely like a hospital-smell type and I thought, 'Wow, that's the smell of space.' The more I thought about it, I thought: 'Wow, this is what nothing smells like, because there's probably nothing left in there, not a single microbe or anything.'" Canadian astronaut Chris Hatfield, meanwhile, described it differently, noting in 2013 that he and many others aboard the station reported a "burnt steak and gunpowder" smell in the airlock. "Not exactly a spring garden," he said in a Canadian Space Agency video. Barcenilla says that when it comes to the smells of space, it really depends on what, specifically, you mean. "Most of space is quite empty and … it isn't really going to smell," she said. "But it's when you get to specific planets or moons, or when you go to a molecular cloud where we find high concentrations of different gases and microscopic dust, that we can then find molecules and chemical compounds that have a smell." Barcenilla says she's created 25 smells since she began doing this work in 2017. For the museum exhibit, she whipped up the scent of Mars, which is her scientific specialty; Titan, a large moon orbiting the planet Saturn; Bennu, an asteroid; and Earth as it was some 3.5-4 billion years ago, when life was just beginning. "The early Earth is a bit smelly. It's a combination of a little bit of kind of earthy wet smell, like what you get when it rains, but also with the smell that you get from various microbial strains," she said. "One of the smells that you get is a kind of sulphury cabbagey smell that goes in there as well. So that's a bit stinky." She admits that none of her creations can be fact-checked, per se. "In space, you can't smell so it's always going to be impossible. We don't have air that we can breathe, so that's completely out of the question," she said. "But what I'm trying to do is recreate the chemistry that we find in various places in space." 'The more it stinks, the more people like to smell it' Barcenilla has brought her space smells to schools to teach children, and she's also had a chance to watch people interact with them at the museum. "I always thought people are going to be a bit scared about the smelly stuff, but no, those are the best ones," she said. "The more it stinks, the more people like to smell it and the more they laugh and the more questions they ask about it." Triggering that curiosity, she says, is the whole point. "It's about bringing space closer to Earth, and it's for people to open their minds and understand that everything that we have out there in space has also ended up here on Earth," she said. As foreign as the final frontier may seem, Barcenilla says there's nothing out there that's truly unfamiliar, at least from an olfactory perspective. Jupiter's inner clouds? Barcenilla tells BBC News they're full of ammonia and sulphur, something you might find in fertilizer, and which smells like rotten eggs. The very centre of our galaxy? There you'll find Ethyl formate, a compound commonly found in fruit, and which probably smells, at best, like rum, and at worst, like nail polish remover.
The Independent
29-05-2025
- General
- The Independent
The truth is out there? Why the scientific community struggles to accept ‘proof' of alien life
The search for extraterrestrial life has long gone back and forth between scientific curiosity, public fascination and outright scepticism. Recently, scientists claimed the 'strongest evidence' of life on a distant exoplanet – a world outside our solar system. Grandiose headlines often promise proof that we are not alone, but scientists remain cautious. Is this caution unique to the field of astrobiology? In truth, major scientific breakthroughs are rarely accepted quickly. Newton's laws of motion and gravity, Wegener's theory of plate tectonics, and human-made climate change all faced prolonged scrutiny before achieving consensus. But does the nature of the search for extraterrestrial life mean that extraordinary claims require even more extraordinary evidence? We've seen groundbreaking evidence in this search beforehand, from claims of biosignatures (potential signs of life) in Venus's atmosphere to Nasa rovers finding 'leopard spots' – a potential sign of past microbial activity – in a Martian rock. Both stories generated a public buzz around the idea that we might be one step closer to finding alien life. But on further inspection, abiotic (non-biological) processes or false detection became more likely explanations. In the case of the exoplanet, K2-18 b, scientists working with data from the James Webb Space Telescope (JWST) announced the detection of gases in the planet's atmosphere – methane, carbon dioxide, and more importantly, two compounds called dimethyl sulphide (DMS) and dimethyl disulphide (DMDS). As far as we know, on Earth, DMS/DMDS are produced exclusively by living organisms. Their presence, if accurately confirmed in abundance, would suggest microbial life. The researchers even suggest there's a 99.4% probability that the detection of these compounds wasn't a fluke – a figure that, with repeat observations, could reach the gold standard for statistical certainty in the sciences. This is a figure known as five sigma, which equates to about a one in a million chance that the findings are a fluke. So why hasn't the scientific community declared this the discovery of alien life? The answer lies in the difference between detection and attribution, and in the nature of evidence itself. JWST doesn't directly 'see' molecules. Instead, it measures the way that light passes through or bounces off a planet's atmosphere. Different molecules absorb light in different ways, and by analysing these absorption patterns – called spectra – scientists infer what chemicals are likely to be present. This is an impressive and sophisticated method – but also an imperfect one. It relies on complex models that assume we understand the biological reactions and atmospheric conditions of a planet 120 light years away. The spectra suggesting the existence of DMS/DMDS may be detected because you cannot explain the spectrum without the molecule you've predicted, but it could also result from an undiscovered or misunderstood molecule instead. Climate comparison Given how momentous the conclusive discovery of extraterrestrial life would be, these assumptions mean that many scientists err on the side of caution. But is this the same for other kinds of science? Let's compare with another scientific breakthrough: the detection and attribution of human-made climate change. The relationship between temperature and increases in CO₂ was first observed by the Swedish scientist Svante Arrhenius in 1927. It was only taken seriously once we began to routinely measure temperature increases. But our atmosphere has many processes that feed CO₂ in and out, many of which are natural. So the relationship between atmospheric CO₂ and temperature may have been validated, but the attribution still needed to follow. Carbon has three so-called flavours, known as isotopes. One of these isotopes, carbon-14, is radioactive and decays slowly. When scientists observed an increase in atmospheric carbon dioxide but a low volume of carbon-14, they could deduce that the carbon was very old – too old to have any carbon-14. Fossil fuels – coal, oil and natural gas – are composed of ancient carbon and thus are devoid of carbon-14. So the attribution of anthropogenic climate change was proven beyond reasonable doubt, with 97% acceptance among scientists. In the search for extraterrestrial life, much like climate change, there is a detection and attribution phase, which requires the robust testing of hypotheses and also rigorous scrutiny. In the case of climate change, we had in situ observations from many sources. This means roughly that we could observe these sources close up. The search for extraterrestrial life relies on repeated observations from the same sensors that are far away. In such situations, systematic errors are more costly. Further to this, both the chemistry of atmospheric climate change and fossil fuel emissions were validated with atmospheric tests under lab conditions from 1927 onwards. Much of the data we see touted as evidence for extraterrestrial life comes from light years away, via one instrument, and without any in situ samples. The search for extraterrestrial life is not held to a higher standard of scientific rigour, but it is constrained by an inability to independently detect and attribute multiple lines of evidence. For now, the claims about K2-18 b remain compelling but inconclusive. That doesn't mean we aren't making progress. Each new observation adds to a growing body of knowledge about the universe and our place in it. The search continues – not because we're too cautious, but because we are rightly so. Oliver Swainston is a Research Assistant at RAND Europe. Chris Carter is an Analyst on the Science and Emerging Technology Team at RAND Europe.
