Latest news with #AmandaSteckel
Yahoo
17-05-2025
- Science
- Yahoo
Scientists find subtle clues ancient Mars had rainy days, too
For the past four years, NASA's Perseverance rover has rambled over a region of Mars where scientists say a strong river once emptied into a crater, creating a large delta. But for that to have happened, a lot of water would have gushed — something difficult to explain if the Red Planet were always frozen. Computer simulations show that ancient Mars likely experienced regular rain and snow, which helped shape vast networks of river valleys and lakes. The distribution of these land features lines up better with precipitation models than merely the effects of melted ice caps, according to a new paper published in the Journal of Geophysical Research: Planets. The research, performed by geologists at the University of Colorado in Boulder, argues that our planetary neighbor, on average 140 million miles away in space, was warm and wet billions of years ago, challenging a long-held belief that early Mars was mostly cold and icy. Most scientists agree that at least some water existed on the surface during a period about 4 billion years ago, but where the water came from has been up for debate, said Amanda Steckel, who led the study as a doctoral student. "We see these valleys beginning at a large range of elevations," Steckel said in a statement. "It's hard to explain that with just ice." SEE ALSO: A NASA rover just exposed something on Mars that eluded orbiters NASA's Mars Global Surveyor spacecraft created this topographical map of a region near the planet's equator with its Mars Orbiter Laser Altimeter. Credit: NASA The researchers created a digital version of part of Mars and tested different climate scenarios. In some computer simulations, they added widespread rain or snow. For others, they only tried melting down polar ice. Then, they used the software to simulate what would happen if that water flowed for thousands of years. Their goal was to determine whether ancient Mars may have had a more Earth-like climate, at least for a while. The results showed when precipitation was part of the climate, valleys and streams formed in many different regions at varying elevation points. When water came only from melted ice, the valleys mostly formed in the highlands, in close proximity to where the ice caps would have been. The team compared the simulation data to real images from NASA spacecraft that have observed Mars from orbit. The patterns created by rain or snow more closely matched what is actually seen on the Martian surface. Mars' oldest terrains appear to have eroded into branching valleys, similar to regions of Earth where rain and snow have caused runoff. Credit: NASA / JPL-Caltech / Univ. of Arizona "Water from these ice caps starts to form valleys only around a narrow band of elevations," Steckel said. "Whereas if you have distributed precipitation, you can have valley heads forming everywhere." Today, snow occasionally falls on Mars, but only in the coldest extremes, according to NASA: at the poles and under cloud cover at night. So far there's no photographic evidence of Martian snowfall — clouds obscure the cameras on spacecraft — but other instruments are capable of detecting it. The Mars Reconnaissance Orbiter, for example, has the Mars Climate Sounder, which has collected data on carbon dioxide snow — aka dry ice — as it fell to the ground. The Phoenix lander also used a laser-based tool to spot snow made of water near the Martian north pole in 2008. The team still doesn't fully grasp how Mars could have stayed warm enough for rain or snow, especially since the young sun was about 25 percent dimmer than it is today. Despite the mystery, geologist and study coauthor Brian Hynek says without rain, landforms like Perseverance's Jezero Crater just don't make sense. The dried delta, for example, features scattered boulders. "You'd need meters deep of flowing water to deposit those kinds of boulders," he said.
Yahoo
16-05-2025
- Science
- Yahoo
Did it snow on Mars? New research suggests ancient Red Planet precipitation was a lot like Earth
Was Mars a friendly planet for water, even life, in its ancient past? Huge channel networks run across its surface. Rocks show signs of water immersion. Yet pictures sent back from NASA's Curiosity and Perseverance rover missions continue to show their tracks in the endless desert. Where did the water come from, how much of it was there, and why did it leave? While the question of water is massively complex, a recent study in the Journal of Geophysical Research: Planets adds to the debate about how ancient water flowed – from the Red Planet's still icy poles, or in a water cycle that included precipitation, or in some combination. Precipitation, to be clear, includes any variant – not just water, but snow or freezing rain and other forms of water falling from the sky. Much like the Eastern Seaboard in winter, a "warm" Mars likely means slightly warmer than freezing, lead author Amanda Steckel said. "Of course, we don't have [direct] access to Mars yet, so we tried to be really simple," Steckel told Salon. She did the study's work as a doctoral student at the University of Colorado Boulder, and has since moved to the California Institute of Technology as a postdoctoral scholar and research associate in planetary science. The study used landscape modeling techniques developed at CU Boulder. They placed a grid on a virtual surface and then ran models of a watery Martian climate to see how it evolved over time. To do so, they broke down the complexity of the climate into two scenarios, ideal for modeling and testing which might be stronger: ice caps pulling water downhill and forming the valley heads at a single elevation, or a precipitation-driven planet that created valley heads at many altitudes. The authors compared their work with imagery of Mars in the equatorial southern highlands, which is heavily cratered but also full of valley networks. They particularly focused on the valley heads, which is the source of the water in each of the networks. And what they found suggests that some kind of water did fall on Mars, as the valley heads were situated at many elevations – a situation that is hard to explain with ice. And it also matches what is observed on Mars, where variations in valley heads range in altitude between thousands of currently does snow on Mars — just not really like it does here and far less frequently. As NASA's Jet Propulsion Laboratory puts it, "Cold as it is, don't expect snow drifts worthy of the Rocky Mountains." Indeed, there are two kinds of snow on Mars: water ice and carbon dioxide, better known as dry ice, which has flakes that are actually cube-shaped. "Because Martian air is so thin and the temperatures so cold, water-ice snow sublimates, or becomes a gas, before it even touches the ground. Dry-ice snow actually does reach the ground," NASA's website states. That's pretty different from what we experience on Earth or what Mars may have had long ago. That said, a lot more study will be required to understand the weird history of water on Mars. To be sure, Mars likely hosted some kind of water on the surface between 3.7 billion and 4.1 billion years ago, when Earth and the rest of the solar system were still young. But how exactly the water flowed is an open question. The young sun was likely burning a little cooler than it is today, raising questions about how much of its warmth reached the surface. The Martian atmosphere also might have been thicker, allowing water to flow more easily – that is, until solar pressure eroded the lighter molecules into space and thinned the planet's protective "envelope" into the thin amount we see today. That's because Mars, for all its charm, has a lower gravity than Earth and less ability to hold on to atmospheric compounds like carbon dioxide. Steckel emphasized that even accepting the idea that precipitation fell on Mars, it was unlikely to be the only way that water moved around on the surface. After all, recent studies of the Red Planet have not only suggested water in the icy poles, but underground. Smaller sources of water may also have come from ancient meteorite strikes. "This is not a climate modeling study," she said of her work, adding her hope is that other climate scientists can use the data set to help inform future studies of the Red Planet. "There's a wide swath of possibilities" between the two water scenarios that her study identified, but to push forward on that, "I think that's where the climate modelers come in … when people try to replicate this dataset with climate modeling, that would be the natural next step." Hansjörg Seybold, a physicist at ETZ not affiliated with the new study, said the methodology was sound but it was only one piece of understanding how liquid water shaped the Martian surface. Studies like this, he emphasized, are limited as they are based on a theoretical Red Planet surface and do not aim to exactly match what is seen in today's channel networks. If Mars was "warm and wet," he continued, valley heads could be seen anywhere where rain accumulates. If the planet was instead a cold and wet location — fed by icy glaciers — the heads would be fed from a single elevation and would not create new branches downstream. "In the end, we are left with one more hint telling us that we actually don't understand Mars' ancient climate and the processes forming its channel networks," he emphasized. "If either of the two cases is actually real remains elusive, and leaves the underlying question of how Mars could have sustained a hydrological cycle open." Seybold said future studies should not only consider the valley networks, but also the geology of the area that we have picked up from Mars rover missions and from observations from orbiting satellites. Seybold also urged comparison with other planets; he led a study in Science Advances in 2018 that attempted to do just that. Seybold's study compared valley networks on Mars with valley networks on Earth to see if groundwater was important to forming Red Planet valley connections. They found that the Martian valleys' branching angles "are more similar to terrestrial valley networks incised by overland flow, than valley networks incised by re-emerging groundwater flow." Understanding the history of weather on Mars helps us learn more about our own planet, as well as informing us of the possibilities of life on the Red Planet and its potential to (maybe) someday host humans.
BBC News
26-04-2025
- Science
- BBC News
New study says Mars could have been a warm, wet planet
New research suggests Mars - which we know as a very cold, dry, rocky planet - may once have actually been warmer and study carried out by scientists at the University of Colorado at Boulder, said that rain and snow may have fallen on the Red Planet billions of years ago, massively shaping the surface of the planet we see today. There is evidence of the existence of water on the planet, which suggests there could have once been life on Mars - as living things need water to survive. The team made computer simulations, from satellite images and rover cameras, to try and guess how the planet developed its craggy terrain we see today. Amongst the areas they looked at was a part of the planet close to the equator. The equator is an imaginary line around the widest part of the planet, half-way between the north and south poles. They used mathematically-powered computer programmes to digitally model what that area would look like if rain and snow fell on it over the course of hundreds of thousands of years. It was then possible to see how the surface of the planet could have changed, taking into account the rain freezing and melting over the years. The researchers concluded that the patterns of dry valleys, riverbeds and lakebeds on Mars today could have been shaped by water, most likely from snow or rain, as they are on Earth."You could pull up Google Earth images of places like Utah, zoom out, and you would see similarities to Mars," Amanda Steckel, planetary geologist and one of the authors of the study said. However, the team noted their research alone was not enough to suggest this was definitely how the planet came to look how it does today, but it was enough to provide new insights into its history.
Yahoo
25-04-2025
- Science
- Yahoo
Mars is covered in evidence of ancient lakes, rain and snow — but scientists aren't sure how that's possible
When you buy through links on our articles, Future and its syndication partners may earn a commission. Though Mars, the Red Planet, is a vast and inhospitable land today, scientists think it once resembled our very own Earth — the Blue Planet, if you will. More specifically, experts say Mars once had a warm, wet climate, and their belief is based on striking geological features on the now-barren world, such as vast valley networks likely carved by flowing water. In fact, a new team of researchers found evidence that Mars may have once had rain — and even snow. However, there's an important mystery buried in the story: It's unclear where Mars' water could have come from, and most climate models predict the world exhibits surface temperatures that are far too cold to sustain liquid water, raising questions about how those visible geological features could have formed. "It's very hard to make any kind of conclusive statement," Amanda Steckel, a postdoctoral researcher at the California Institute of Technology's Division of Geological and Planetary Sciences, said in a statement. "But we see these valleys beginning at a large range of elevations. It's hard to explain that with just ice." Using computer simulations, Steckel and her team dove into what Mars might have looked like about 4 billion years ago during the Noachian epoch, a time when water may have dramatically shaped the planet's surface. Their model, which was actually originally designed for Earth, was adapted to simulate how Mars' landscape evolved near the equator. In this region, sprawling channel networks stretch from the highlands and drain into ancient lakes — possibly even an ocean. NASA's Perseverance rover is currently exploring one of these sites, Jezero Crater, where a powerful river once poured into the basin. "You'd need meters deep of flowing water to deposit those kinds of boulders [seen in Jezero]," said Brian Hynek, senior author of the study and a scientist at the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado, Boulder. Furthermore, what's interesting is that hints about Mars' temperate past are also seen in the geological features on Earth. "You could pull up Google Earth images of places like Utah, zoom out, and you'd see the similarities to Mars," said Steckel. The team tested two main ideas for how Mars' valleys might have formed through precipitation: one where the planet was warm and wet, and another where ice melted temporarily at the edge of a large ice cap — representing a cold, dry climate. Each scenario led to a very different-looking Mars, with valley origins appearing in drastically different locations. In the ice-melt model, valleys mostly began at high elevations, near where the ice would have been. Though that scenario might have initially seemed to match parts of Mars today, the warm and wet version produced much wider spread valley networks forming everywhere from low-lying regions to more than 11,000 feet (3,353 meters) above the planet's average surface. Related Stories: — NASA's Curiosity rover finds major clue that Mars was once habitable — NASA's Perseverance rover hits the Mars rock gold mine: 'It has been all we had hoped for and more' — Curiosity Mars rover discovers largest organic molecules ever seen on Red Planet The latter distribution lines up better with what we actually see on Mars: valley networks scattered across many different elevations and regions. While the ice-melt model fits some local features, the warm and wet version helps explain the planet's landscape on a global scale. "Water from these ice caps starts to form valleys only around a narrow band of elevations," Steckel said. "Whereas if you have distributed precipitation, you can have valley heads forming everywhere." This suggests that precipitation played a significant role in forming these valleys, indicating that ancient Mars likely had a climate warm enough to support rain — and even snow! While more evidence is needed and answers to questions, such as how the planet stayed warm enough for rain or snow, are part of an ongoing investigation. Still, Hynek said the study offers valuable clues, not just about Mars, but about the early history of Earth as well. "Once the erosion from flowing water stopped, Mars almost got frozen in time and probably still looks a lot like Earth did 3.5 billion years ago," he said. The team's study was published on April 21 in the Journal of Geophysical Research: Planets.
India Today
23-04-2025
- Science
- India Today
Did it rain and snow on Mars like Earth?
Did it rain and snow on Mars like Earth? 23 Apr, 2025 Credit: Nasa A new study suggests that billions of years ago, Mars experienced snow or rain, creating rivers and lakes—indicating a much warmer and wetter planet than today. Rain & Rivers Led by Amanda Steckel, the research was published in the Journal of Geophysical Research: Planets and uses new simulations to understand Mars' ancient climate. New Research The study supports the idea that Mars had widespread precipitation, challenging the long-standing theory that it was always cold and dry with only occasional ice melt. Cold-and-Dry Theory Satellite data show valley networks on Mars similar to Earth's, especially places like Utah, suggesting formation through flowing water—not just melting ice. Earth-Like Valley Researchers simulated both melting ice caps and precipitation. Rainfall scenarios created more realistic valley formations across varied elevations, closely matching Mars' real terrain. Rainfall Hypothesis Mars' Jezero Crater, currently explored by NASA's Perseverance rover, is an example of an ancient lake fed by a strong river—likely requiring meters-deep water flow. Perseverance Rover Hunts While the study strengthens the warm-and-wet theory, scientists still don't fully understand how early Mars stayed warm enough for liquid water. The planet may be a snapshot of what early Earth once looked like. Still a Mystery
