Latest news with #Valantinas
Yomiuri Shimbun
3 days ago
- Science
- Yomiuri Shimbun
Study Doubts Water Flows Caused Streaks on Martian Slopes
NASA / Handout via Reuters Dark finger-like slope streaks extending across the dusty Martian surface in a region called Arabia Terra are seen in this NASA satellite photo released on May 19. WASHINGTON (Reuters) — Images taken of Mars from orbit dating back as far as the 1970s have captured curious dark streaks running down the sides of cliffs and crater walls that some scientists have construed as possible evidence of flows of liquid water, suggesting that the planet harbors environments suitable for living organisms. A new study casts doubt on that interpretation. Examining about 500,000 of these sinewy features spotted in satellite images, the researchers concluded they were created probably through dry processes that left the superficial appearance of liquid flows, underscoring the view of Mars as a desert planet currently inhospitable to life — at least on its surface. The data indicated that formation of these streaks is driven by the accumulation of fine-grain dust from the Martian atmosphere on sloped terrain that is then knocked down the slopes by triggers such as wind gusts, meteorite impacts and marsquakes. 'The tiny dust particles can create flow-like patterns without liquid. This phenomenon occurs because extremely fine dust can behave similarly to a liquid when disturbed — flowing, branching and creating finger-like patterns as it moves downslope,' said Adomas Valantinas, a postdoctoral researcher in planetary sciences at Brown University and coleader of the study published on May 19 in the journal Nature Communications. 'It's similar to how dry sand can flow like water when poured. But on Mars, the ultra-fine particles and low gravity enhance these fluid-like properties, creating features that might be mistaken for water flows when they're actually just dry material in motion,' Valantinas added. The study examined about 87,000 satellite images — including those obtained between 2006 and 2020 by a camera aboard NASA's Mars Reconnaissance Orbiter — of slope streaks, which form suddenly and fade over a period of years. They average roughly 600-775 meters long, sometimes branching out and going around obstacles. The slope streaks were concentrated mostly in the northern hemisphere, particularly in three major clusters: at the plains of Elysium Planitia, the highlands of Arabia Terra and the vast Tharsis volcanic plateau including the Olympus Mons volcano, towering about three times higher than Mount Everest. The researchers said limitations in the resolution of the satellite images mean they account for only a fraction of slope streaks. They estimated the actual number at up to two million. Water is considered an essential ingredient for life. Mars billions of years ago was wetter and warmer than it is today. The question remains whether Mars has any liquid water on its surface when temperatures seasonally can edge above the freezing point. It remains possible that small amounts of water — perhaps sourced from buried ice, subsurface aquifers or abnormally humid air — could mix with enough salt in the ground to create a flow even on the frigid Martian surface. That raises the possibility that the slope streaks, if caused by wet conditions, could be habitable niches. 'Generally, it is very difficult for liquid water to exist on the Martian surface, due to the low temperature and the low atmospheric pressure. But brines — very salty water — might potentially be able to exist for short periods of time,' said planetary geomorphologist and study coleader Valentin Bickel of the University of Bern in Switzerland. Given the massive volume of images, the researchers employed an advanced machine-learning method, looking for correlations involving temperature patterns, atmospheric dust deposition, meteorite impacts, the nature of the terrain and other factors. The geostatistical analysis found that slope streaks often appear in the dustiest regions and correlate with wind patterns, while some form near the sites of fresh impacts and quakes. The researchers also studied shorter-lived features called recurring slope lineae, or RSL, seen primarily in the Martian southern highlands. These grow in the summer and fade the following winter. The data suggested that these also were associated with dry processes such as dust devils — whirlwinds of dust — and rockfalls. The analysis found that both types of features were not typically associated with factors indicative of a liquid or frost origin such as high surface temperature fluctuations, high humidity or specific slope orientations. 'It all comes back to habitability and the search for life,' Bickel said. 'If slope streaks and RSL would really be driven by liquid water or brines, they could create a niche for life. However, if they are not tied to wet processes, this allows us to focus our attention on other, more promising locations.'
India Today
20-05-2025
- Science
- India Today
Study casts doubt on water flows as cause of streaks on Martian slopes
Images taken of Mars from orbit dating back as far as the 1970s have captured curious dark streaks running down the sides of cliffs and crater walls that some scientists have construed as possible evidence of flows of liquid water, suggesting that the planet harbors environments suitable for living organisms.A new study casts doubt on that interpretation. Examining about 500,000 of these sinewy features spotted in satellite images, the researchers concluded they were created probably through dry processes that left the superficial appearance of liquid flows, underscoring the view of Mars as a desert planet currently inhospitable to life - at least on its data indicated that formation of these streaks is driven by the accumulation of fine-grain dust from the Martian atmosphere on sloped terrain that is then knocked down the slopes by triggers such as wind gusts, meteorite impacts and marsquakes."The tiny dust particles can create flow-like patterns without liquid. This phenomenon occurs because extremely fine dust can behave similarly to a liquid when disturbed - flowing, branching and creating finger-like patterns as it moves downslope," said Adomas Valantinas, a postdoctoral researcher in planetary sciences at Brown University and co-leader of the study published on Monday in the journal Nature Communications."It's similar to how dry sand can flow like water when poured. But on Mars, the ultra-fine particles and low gravity enhance these fluid-like properties, creating features that might be mistaken for water flows when they're actually just dry material in motion," Valantinas study examined about 87,000 satellite images - including those obtained between 2006 and 2020 by a camera aboard NASA's Mars Reconnaissance Orbiter - of slope streaks, which form suddenly and fade over a period of years. They average roughly 1,970-2,540 feet (600-775 meters) long, sometimes branching out and going around slope streaks were concentrated mostly in the northern hemisphere, particularly in three major clusters: at the plains of Elysium Planitia, the highlands of Arabia Terra and the vast Tharsis volcanic plateau including the Olympus Mons volcano, towering about three times higher than Mount researchers said limitations in the resolution of the satellite images mean they account for only a fraction of slope streaks. They estimated the actual number at up to two is considered an essential ingredient for life. Mars billions of years ago was wetter and warmer than it is today. The question remains whether Mars has any liquid water on its surface when temperatures seasonally can edge above the freezing remains possible that small amounts of water - perhaps sourced from buried ice, subsurface aquifers or abnormally humid air - could mix with enough salt in the ground to create a flow even on the frigid Martian surface. That raises the possibility that the slope streaks, if caused by wet conditions, could be habitable it is very difficult for liquid water to exist on the Martian surface, due to the low temperature and the low atmospheric pressure. But brines - very salty water - might potentially be able to exist for short periods of time," said planetary geomorphologist and study co-leader Valentin Bickel of the University of Bern in the massive volume of images, the researchers employed an advanced machine-learning method, looking for correlations involving temperature patterns, atmospheric dust deposition, meteorite impacts, the nature of the terrain and other factors. The geostatistical analysis found that slope streaks often appear in the dustiest regions and correlate with wind patterns, while some form near the sites of fresh impacts and researchers also studied shorter-lived features called recurring slope lineae, or RSL, seen primarily in the Martian southern highlands. These grow in the summer and fade the following winter. The data suggested that these also were associated with dry processes such as dust devils - whirlwinds of dust - and analysis found that both types of features were not typically associated with factors indicative of a liquid or frost origin such as high surface temperature fluctuations, high humidity or specific slope orientations."It all comes back to habitability and the search for life," Bickel said. "If slope streaks and RSL would really be driven by liquid water or brines, they could create a niche for life. However, if they are not tied to wet processes, this allows us to focus our attention on other, more promising locations."Must Watch
Gulf Today
20-05-2025
- Science
- Gulf Today
Study questions presence of liquid water on Mars
Images taken of Mars from orbit dating back as far as the 1970s have captured curious dark streaks running down the sides of cliffs and crater walls that some scientists have construed as possible evidence of flows of liquid water, suggesting that the planet harbors environments suitable for living organisms. A new study casts doubt on that interpretation. Examining about 500,000 of these sinewy features spotted in satellite images, the researchers concluded they were created probably through dry processes that left the superficial appearance of liquid flows, underscoring the view of Mars as a desert planet currently inhospitable to life – at least on its surface. The data indicated that formation of these streaks is driven by the accumulation of fine-grain dust from the Martian atmosphere on sloped terrain that is then knocked down the slopes by triggers such as wind gusts, meteorite impacts and marsquakes. "The tiny dust particles can create flow-like patterns without liquid. This phenomenon occurs because extremely fine dust can behave similarly to a liquid when disturbed – flowing, branching and creating finger-like patterns as it moves downslope," said Adomas Valantinas, a postdoctoral researcher in planetary sciences at Brown University and co-leader of the study published on Monday in the journal Nature Communications. "It's similar to how dry sand can flow like water when poured. But on Mars, the ultra-fine particles and low gravity enhance these fluid-like properties, creating features that might be mistaken for water flows when they're actually just dry material in motion," Valantinas added. The study examined about 87,000 satellite images – including those obtained between 2006 and 2020 by a camera aboard NASA's Mars Reconnaissance Orbiter – of slope streaks, which form suddenly and fade over a period of years. They average roughly 1,970-2,540 feet (600-775 metres) long, sometimes branching out and going around obstacles, according to Reuters. The slope streaks were concentrated mostly in the northern hemisphere, particularly in three major clusters: at the plains of Elysium Planitia, the highlands of Arabia Terra and the vast Tharsis volcanic plateau including the Olympus Mons volcano, towering about three times higher than Mount Everest. The researchers said limitations in the resolution of the satellite images mean they account for only a fraction of slope streaks. They estimated the actual number at up to two million. Water is considered an essential ingredient for life. Mars billions of years ago was wetter and warmer than it is today. The question remains whether Mars has any liquid water on its surface when temperatures seasonally can edge above the freezing point. It remains possible that small amounts of water – perhaps sourced from buried ice, subsurface aquifers or abnormally humid air – could mix with enough salt in the ground to create a flow even on the frigid Martian surface. That raises the possibility that the slope streaks, if caused by wet conditions, could be habitable niches. Given the massive volume of images, the researchers employed an advanced machine-learning method, looking for correlations involving temperature patterns, atmospheric dust deposition, meteorite impacts, the nature of the terrain and other factors. The geostatistical analysis found that slope streaks often appear in the dustiest regions and correlate with wind patterns, while some form near the sites of fresh impacts and quakes, the Reuters report adds. The researchers also studied shorter-lived features called recurring slope lineae, or RSL, seen primarily in the Martian southern highlands. These grow in the summer and fade the following winter. The data suggested that these also were associated with dry processes such as dust devils – whirlwinds of dust – and rockfalls. The analysis found that both types of features were not typically associated with factors indicative of a liquid or frost origin such as high surface temperature fluctuations, high humidity or specific slope orientations.
The Herald
20-05-2025
- Science
- The Herald
Study casts doubt on water flows as cause of streaks on Martian slopes
"It's similar to how dry sand can flow like water when poured. But on Mars, the ultra-fine particles and low gravity enhance the fluid-like properties, creating features that might be mistaken for water flows when they're dry material in motion," Valantinas said. The study examined about 87,000 satellite images, including those obtained between 2006 and 2020 by a camera aboard Nasa's Mars Reconnaissance Orbiter, of slope streaks, which form suddenly and fade over years. They average roughly 600m to 775m long, sometimes branching out and going around obstacles. The slope streaks were concentrated mostly in the northern hemisphere, particularly in three major clusters: at the plains of Elysium Planitia, the highlands of Arabia Terra and the vast Tharsis volcanic plateau including the Olympus Mons volcano, towering about three times higher than Mount Everest. The researchers said limitations in the resolution of the satellite images mean they account for only a fraction of slope streaks. They estimated the number at up to two million. Water is considered an essential ingredient for life. Mars billions of years ago was wetter and warmer than it is today. The question remains whether Mars has any liquid water on its surface when temperatures seasonally can edge above the freezing point. It remains possible that small amounts of water, perhaps sourced from buried ice, subsurface aquifers or abnormally humid air, could mix with enough salt in the ground to create a flow even on the frigid Martian surface. That raises the possibility that the slope streaks, if caused by wet conditions, could be habitable niches. "Generally, it is very difficult for liquid water to exist on the Martian surface due to the low temperature and the low atmospheric pressure. But brines, or very salty water, might potentially be able to exist for short periods of time," said planetary geomorphologist and study co-leader Valentin Bickel of the University of Bern in Switzerland. Given the massive volume of images, the researchers employed an advanced machine-learning method, looking for correlations involving temperature patterns, atmospheric dust deposition, meteorite impacts, the nature of the terrain and other factors. The geostatistical analysis found slope streaks often appear in the dustiest regions and correlate with wind patterns, while some form near the sites of fresh impacts and quakes. The researchers also studied shorter-lived features called recurring slope lineae, or RSL, seen primarily in the Martian southern highlands. These grow in the summer and fade the next winter. The data suggested these also were associated with dry processes such as dust devils, or whirlwinds of dust, and rockfalls. The analysis found both types of features were not typically associated with factors indicative of a liquid or frost origin such as high surface temperature fluctuations, high humidity or specific slope orientations. "It all comes back to habitability and the search for life," Bickel said. "If slope streaks and RSL would be driven by liquid water or brines, they could create a niche for life. However, if they are not tied to wet processes, this allows us to focus our attention on other, more promising locations." Reuters )
Yahoo
20-05-2025
- Science
- Yahoo
Dark streaks on Mars may not come from water after all, scientists say
When you buy through links on our articles, Future and its syndication partners may earn a commission. First identified in the 1970s by NASA's Viking mission, long, dark markings snake down Martian slopes, sometimes stretching across Mars' surface for hundreds of feet. Scientists have watched some of these markings exist for decades, while others, known as "recurring slope lineae," appear to fade in a single season. Nonetheless, they all starkly stand out against the planet's dusty red surface. Given that modern Mars is dry and arid, with temperatures rarely climbing above the freezing point of water, the origin of these streaks has long been a topic of heated debate. For years, they were seen as one of the most compelling signs that liquid water might still exist on Mars, suggesting a rare pocket of habitability on an otherwise arid planet. The leading theory speculated that salty water was seeping from underground sources — like buried ice or subsurface aquifers — allowing it to briefly flow across the cold Martian surface. But new evidence suggests something else might be driving the phenomenon. "A big focus of Mars research is understanding modern-day processes on Mars — including the possibility of liquid water on the surface," said Adomas Valantinas, a postdoctoral researcher at Brown University in a statement. "Our study reviewed these features but found no evidence of water. Our model favors dry formation processes." Using machine learning to analyze a massive dataset of over 86,000 high-resolution satellite images of these streaks, Valantinas and his colleagues now believe that wind and dust — rather than flowing water — are the more likely culprits. To figure this out, they created the first global map of Martian slope streaks, cataloging over 500,000 individual features across the planet's surface. "Once we had this global map, we could compare it to databases and catalogs of other things like temperature, wind speed, hydration, rockslide activity and other factors," said Valentin Bickel, a researcher at the University of Bern. "Then we could look for correlations over hundreds of thousands of cases to better understand the conditions under which these features form." The geostatistical analysis revealed that slope streaks and recurring slope lineae don't appear in places where you'd expect to find signs of liquid water or frost. For instance, watery slopes would be expected to face a specific direction, experience extreme temperature swings, or exist in high humidity. Instead, the study found that these streaky features are more common in areas with stronger winds and heavier dust activity. Related Stories: — Trump's 2026 budget plan would cancel NASA's Mars Sample Return mission. Experts say that's a 'major step back' — Perseverance Mars rover becomes 1st spacecraft to spot auroras from the surface of another world — 'Marsquakes' reveal clues about a hidden body of water on Mars The researchers say this points to the streaks forming when thin layers of fine dust slide down a steep hillside. What precisely causes these slides can differ, the team explains, but slope streaks tend to show up more often near fresh impact craters. There, the shock from an impact might shake dust loose. Meanwhile, recurring slope lineae are usually found in areas where dust devils or rockfalls happen frequently. Understanding how features like slope streaks and recurring slope lineae form is crucial in the quest to unlock the secrets of Mars and guide future Red Planet exploration efforts. By using a big data approach to study these patterns from orbit, scientists can eliminate certain possibilities without having to send costly missions to the surface. This means missions can focus more efficiently on the most promising locations — bringing us closer to discovering whether Mars could have supported life and ensuring we protect the planet's fragile environments as we send spacecraft deeper and deeper into space. The study was published on May 19 in the journal Nature Communications.
