Latest news with #UniversityofBern
TimesLIVE
20-05-2025
- Science
- TimesLIVE
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." )
Yahoo
20-05-2025
- Science
- Yahoo
Curious circles on Venus suggest its surface is still changing
When you buy through links on our articles, Future and its syndication partners may earn a commission. A new study reveals overlooked signs of geological activity on Venus — clues that the planet's mysterious surface is still changing today. These signs, found in giant circular features called "coronae," may not only reshape our understanding of Venus, but also offer a glimpse into Earth's own ancient past. Coronae are vast, oval-shaped structures ranging in size from dozens to hundreds of miles wide. They are believed to form when hot, plumes from deep inside a planet push against its outer shell called the lithosphere. Imagine a slow-motion bubble of molten rock pressing upward beneath the surface, warping and cracking the crust above. These dramatic geological features, encircled by rings of fractures, are scattered across Venus, offering a stunning window into the planet's inner workings, scientists say. "They are very large features, and people have proposed different theories over the years as to how they formed," said coauthor Anna Gülcher, a planetary scientist at the University of Bern in Switzerland, in a NASA/JPL statement. "The most exciting thing for our study is that we can now say there are most likely various and ongoing active processes driving their formation." These massive ovals once dotted our planet's landscape, so studying them on Venus can reveal much about both planets, scientists say. "Coronae are not found on Earth today; however, they may have existed when our planet was young and before plate tectonics had been established," said the study's lead author, Gael Cascioli, assistant research scientist at the University of Maryland, Baltimore County, and NASA's Goddard Space Flight Center in Greenbelt, Maryland in the statement. "By combining gravity and topography data, this research has provided a new and important insight into the possible subsurface processes currently shaping the surface of Venus." To figure out the most likely process behind the formation of coronae on Venus, the team built a 3D computer model that simulates the flow of hot material inside the planet — like a virtual experiment of the planet's inner workings. They tested different formation scenarios and compared their results with gravity and topography data collected by NASA's Magellan spacecraft, which mapped Venus in the early 1990s. The gravity data, which measured the strength of gravity at different points along the planet's surface, turned out to be a game-changer. This is because denser material pulls more strongly on nearby objects, while less dense material exerts a weaker pull. The data helped the scientists detect hidden plumes of hot, less dense material rising from deep inside Venus, something that surface maps alone couldn't reveal. Out of 75 coronae examined, 52 showed signs of these underground forces still at work, hinting that tectonic activity may be more widespread on Venus than previously thought. The team believes that several tectonic processes may be shaping Venus's surface around the coronae. In some cases, subduction-like activity — a process where one part of a planet's outer shell is forced downward into the hotter, deeper interior — occurs as hot plumes rise and push surface material outward and downward. This is similar to how tectonic plates interact on Earth. They also say that another process called lithospheric dripping, which involves cooler, heavier parts of the surface sinking into the hotter mantle below, could be responsible for the tectonic activity underlying the coronae. A third possibility is that plumes beneath thicker crust trigger volcanic activity above. RELATED STORIES: — Venus facts: Everything you need to know about the 2nd planet from the sun — How 'Earth's twin' Venus lost its water and became a hellish planet — Mysteries of Crown-like Structures on Venus' Surface Unveiled in New Study Whatever the cause of the coronae might be, they suggest that Venus may be geologically active in complex and varied ways, giving researchers insight into how tectonics might work on planets without Earth-like plate boundaries — and possibly how Earth looked in its earlier, more dynamic past. While a significant and extensive study, the team relied on old data, and higher resolution images captured by the upcoming VERITAS mission will help them clarify their results. "The VERITAS gravity maps of Venus will boost the resolution by at least a factor of two to four, depending on location — a level of detail that could revolutionize our understanding of Venus' geology and implications for early Earth," said study coauthor Suzanne Smrekar, a planetary scientist at JPL and principal investigator for VERITAS, in JPL's statement. VERITAS is set to launch in 2031. A study of coronae on Venus was published in the journal Science Advances.
Scientific American
14-05-2025
- Science
- Scientific American
Venus Isn't (Geologically) Dead
Earth's geology is downright vital. Here, giant 'plates' of the crust rift apart and smash together like pieces of an ever changing planetary jigsaw puzzle. Mountains rise, volcanoes spew, and Earth itself quakes as the crust constantly remakes itself in the ceaseless cycle of plate tectonics. This is a process that controls the flow of carbon through our planet and stabilizes its climate; were it not for plate tectonics, Earth might not be habitable at all. No other rocky world in our solar system has anything approaching Earth's degree of geological activity. At least, that's what scientists used to think. Mercury, Mars and the moon appear essentially inert. But Venus, our closest neighbor and the only other large rocky world around the sun, is now starting to look far livelier than once thought. A fresh look at decades-old data from NASA's Magellan probe has found evidence of active tectonics—around dozens of circular volcanic features called coronae—on Venus today. The finding, published on Wednesday in Science Advances, provides some of the best evidence to date that Venus isn't dead—at least, not when it comes to tectonics. 'Venus works differently than the Earth but not as different as what was originally assumed,' says the study's co-lead author Anna Gülcher of the University of Bern in Switzerland. 'We should think of tectonics as not just a black-and-white picture.' On supporting science journalism If you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today. 'Questions as fundamental as 'Is Venus alive today?' are extremely hard to answer,' says planetary scientist Paul Byrne of the University of Washington in St. Louis, who wasn't involved in the study. This new evidence of geological activity around the coronae suggests 'the heart of Venus still beats today. I think that's extremely invaluable for us to understand the big, rocky world next door.' Venus is called ' Earth's evil twin ' for good reason: the planet is almost exactly as large as the Earth and is made of roughly the same stuff. But while Earth is a verdant water world, Venus is a scorched hellscape with temperatures hot enough to melt lead, a dreary, permanently overcast sky and air so thick that it crushes spacecraft as if they were tin cans. For a while, Venus was widely assumed to be just as dead on the inside as it is on the outside. Lacking any obvious plate tectonics—which can help release a world's internal heat—Venus's interior was thought to instead just simmer like the contents of a tight-lidded pot on a stove. According to one popular hypothesis, the pot had eventually boiled over: after eons of frustrated heating, some 800 million years ago, the planet's outer shell buckled, and Venus's entire surface was paved over with immense outpourings of fresh lava. And, the thinking went, with all that heat dissipated, the planet's geology basically shut down. But evidence is mounting that Venus is, geologically at least, still kicking. Most notably, in 2023 two researchers scrutinizing 30-year-old Magellan data realized that the probe had caught a volcanic eruption in the act: radar images of the volcano Maat Mons that were taken months apart showed what looked like a caldera collapse and subsequent lava flow. Venus, it seems, still has active volcanoes. Some researchers now think it could have active tectonics, too. And in 2020 Gülcher and her colleagues showed via simulations of Venusian tectonics that the planet's mysterious, ring-shaped coronae could be a good place to look for such activity. Tectonics refers to the processes that deform a rocky planet's brittle outer shell. On Earth, this outer shell—the lithosphere, which includes the crust and part of the upper mantle—is broken into tectonic plates that drift over the hot, plastic mantle. When two plates collide, one of them can slide below the other and dive down into the mantle in a process called subduction. On Earth, subducting plates start melting as they sink, feeding volcanoes along plate boundaries. Such volcanoes include Japan's Mount Fuji and western North America's Cascade Range. Unlike Earth, Venus doesn't have global plate tectonics. The new study suggests, however, that around coronae, something quite similar to subduction could be happening. Gülcher and her colleagues simulated several tectonic processes that might be occurring around coronae and compared their predictions to real observations collected by the Magellan probe 30 years ago. The comparisons were more than skin-deep: the researchers used gravity data to take a peek underground. Hot rock is generally less dense than cold rock, and these density variations from place to place can correspondingly alter the strength of a planet's gravitational field. So Magellan's spatial mapping of Venus's gravity can 'see' if there's hot, light material under a corona—a sign that rock is actively rising up from the mantle below. Of the 75 coronae that the team could resolve in Magellan's gravitational maps, 52 seem to be geologically active. The predicted and real data lined up so well for some coronae that 'we could hardly believe our eyes,' says the study's other co-lead author Gael Cascioli of NASA's Goddard Space Flight Center and the University of Maryland, Baltimore County. Most of the active coronae were encircled by trenches, a hint that old crust dives into Venus's mantle around these rocky rings, where it is driven downward as buoyant rock rises from below in the middle of each corona's ring structure. 'Basically, if something goes down, something goes up,' Gülcher says. Where the lithosphere is softer and more pliable, bits of it could break off and 'drip' down into the mantle in globs. In places where the lithosphere is stiffer, entire slabs of crust could subduct in a small-scale, circular mirror of Earth's subduction zones, like those that form the Pacific Ocean's famed volcanic Ring of Fire. Working with 30-year-old data comes with an obvious limitation: the data quality often isn't very good compared with newer observations. The new study's researchers did well with what they had, Byrne says. But NASA's upcoming VERITAS (Venus Emissivity, Radio Science, InSAR, Topography, and Spectroscopy) mission could do much better—and the team predicted exactly how much better in the paper. 'The improvement would be extraordinary,' Cascioli says. Instead of being limited to analyzing 75 coronae, VERITAS's gravity dataset should allow scientists to examine hundreds of the strange ring-shaped features. For the foreseeable future, Venus is the only other large, rocky world that we or our robotic emissaries will ever reach. Understanding why Earth and Venus ended up so different despite having so much in common helps us understand our own planet—and whether the rocky worlds we're beginning to glimpse around other stars are more like Earth or instead resemble its evil twin. 'Venus is the world that we probably understand least,' Byrne says. 'Yet it's the one, arguably, I think, that's the most important.'
Business Mayor
11-05-2025
- Health
- Business Mayor
Weight loss jabs could also help treat mental illness, bombshell new study finds
Could weight loss jabs help beat the blues? (Image: Getty Images) Weight loss jabs could help people beat the blues as well as shed pounds, research shows. Scientists believe appetite suppressing drugs may boost mental health and general wellbeing by lowering inflammation in the brain. A research review being presented at the European Congress on Obesity in Malaga, Spain, is the best evidence yet that the injections could be good for the mind as well as the body. Scientists behind the findings say the hormone imitating medicines should now be trialled specifically to treat mental illness. Obesity is linked to a greater risk of mental illness (stock image) (Image: Getty Images) The Royal College of Psychiatrists has called for patients with mental illness to be prioritised for the drugs. Swiss researchers analysed 36 studies including 26,000 adults in 19 countries and showed that for participants the weekly jabs improved mood, wellbeing and quality of life measures more than insulin and other anti-diabetic drugs. The jabs slow digestion and reduce appetite by mimicking the glucagon-like peptide 1 (GLP-1) hormone which regulates hunger and feelings of fullness. Author Dr Sigrid Breit from the University of Bern, said: 'GLP-1 RAs (receptor agonists) may have antidepressant and anti-anxiety effects, potentially due to their anti-inflammatory and anti-oxidative properties, which can also help reduce neuroinflammation.' GLP-1 jabs were designed to combat diabetes and are now also prescribed to help obese people lose weight however there is increasing evidence they have other benefits (Image: Getty Images) GLP-1 jabs were designed to combat diabetes and are now also prescribed to help obese people lose weight. However there is increasing evidence they have other benefits. It comes amid mounting evidence that insulin resistance and chronic inflammation – hallmarks of diabetes – are also tied to depression and cognitive decline. Previous research has shown that diabetes can affect thinking ability, causing memory loss and brain fog. GLP-1 injections may help fix that by reducing inflammation in the brain, improving how insulin works in the body, and even helping brain cells communicate with each other better. Previous tests on animals also suggest GLP-1 drugs could strengthen memory signals in the brain's hippocampus – a region linked to mood and learning – and could even protect against dementia by improving insulin signalling and reducing damaging oxidative stress. Some weight jabs have seen users lose as much as 20% of their body weight (Image: PA) The latest review looked at studies which included obese patients and some who also had Type 2 diabetes. It included the injections semaglutide – known by its brand names Ozempic or Wegovy, liraglutide – also known as Victoza, exenatide – also known as Byetta or Bydureon, and dulaglutide also known as Trulicity. The review also appeared to disprove early concerns that the drugs increased the risk of suicidal behaviour new mental illness or psychiatric hospital admissions. Five studies found that they were safe and improved mental illness outcome and quality of life in people with schizophrenia spectrum disorders, major depressive disorder, and bipolar effective disorder. Dr Ed Beveridge, spokesman for the Royal College of Psychiatrists, said: 'We know that, for a variety of reasons, many people with mental illness will have weight management issues. Therefore, where clinically assessed as suitable, it is crucial that they are regarded as a priority group for access to semaglutide medication, with appropriate monitoring arrangements in place following prescribing.' Scientists are now calling for further trials to see if weight loss jabs could be prescribed to tackle mental illness. One trial showed better life quality improvements in patients treated with the newer tablet form of semaglutide than with dulaglutide GLP-1 injections. A known side effect of GLP-1s is vomiting and some users have had to come off them and have put the weight back on (Image: Getty Images) Dr Breit said: 'These results are particularly important for people with severe mental disorders who are three times more likely to be living with obesity than the general population. 'This research provides much-needed evidence in support of GLP-1RAs [receptor agonists) to help safely address the burden of obesity in people with mental illness. However, more data from large-scale randomised trials and longer treatment and follow-up periods are needed to establish the long-term efficacy of GLP-1 RAs, as well as future studies exploring whether these medications might be useful for the direct treatment of mental health disorders.' Mental illnesses are associated with an increased risk of weight gain and type 2 diabetes. Weight gain is also a common side effect of mood-altering drugs including antidepressants and antipsychotics, especially for individuals with severe mental illnesses who must take their medications indefinitely to reduce the risk of symptom relapse. Prof Naveed Sattar, obesity expert at Glasgow University, said: 'This [study] is important as many drugs used to treat depression or other psychiatric conditions can lead to weight gain, which can be really troublesome for patients and lead them to develop other comorbidities faster, whereas intentional weight loss would mitigate such impacts.' Half million Brits are already taking the appetite-suppressing injections – mostly via private prescriptions. They are available on the NHS via specialist weight management clinics because of the intensive support users need. Known side effects include vomiting and constipation. Most are purchasing them privately for around £200 a month because the NHS has a waiting list of up to two years. Just one in 10 overweight people who are eligible are currently able to get the powerful drugs on the NHS. Dr Breit added: 'We concluded that GLP-1RAs are safe and effective weight loss treatments for individuals with obesity and mental illness exerting a positive effect on mental state and quality of life. However, the effect on mental state has not been proven yet and further research is needed to assess their long-term effects and their use in improving mental health.'
Telegraph
11-05-2025
- Health
- Telegraph
Weight-loss jabs ‘can treat depression'
Weight-loss jabs could work as antidepressants, research to be presented to the ongoing obesity summit in Spain will suggest. Studies on more than 25,000 adults found evidence that the injections could have a powerful impact on the mind, as well as the body. Scientists called for trials of the drugs to specifically treat mental illness, after research found the class of medication could help people beat the blues. Experts believe appetite-suppressing drugs may have antidepressant and anti-anxiety effects, potentially due to their anti-inflammatory and anti-oxidative properties. Researchers analysed 36 studies including 26,000 adults in 19 countries. The findings, which will be presented to the European Congress on Obesity in Malaga, showed that the weekly jabs improved mood, wellbeing and quality of life measures more than insulin and other anti-diabetic drugs The injections slow digestion and reduce appetite by mimicking the glucagon-like peptide 1 (GLP-1) hormone which regulates hunger and feelings of fullness. Author Dr Sigrid Breit from the University of Bern, Switzerland, said: 'GLP-1 RAs (receptor agonists) may have antidepressant and anti-anxiety effects, potentially due to their anti-inflammatory and anti-oxidative properties, which can also help reduce neuroinflammation.'
