Over two years of data collected on Mars by the SuperCam microphone on NASA’s Perseverance rover has led planetary scientists to identify 55 triboelectric discharge events linked to dust devils and dust storms.
Detection of electrical discharges in dust devils by the SuperCam instrument aboard NASA’s Perseverance rover on Mars. Image credit: Nicholas Sarter.
Lightning and electrical phenomena have been observed on Earth, Saturn, and Jupiter within our solar system.
While the possibility of electrical activity on Mars has been hypothesized, it has never before been directly recorded.
The Martian surface, characterized by frequent dust activities and phenomena such as wind-driven dust, sandstorms, and dust devils, can lead to electrical charges similar to those seen on Earth.
Determining whether such electrification occurs on Mars is vital for understanding the planet’s surface chemistry and assessing the safety of future robotic and human exploration missions.
To investigate this, Baptiste Chide and colleagues from the University of Toulouse examined 28 hours of audio recordings from the Perseverance rover’s SuperCam microphone gathered over two years.
The researchers categorized 55 electrical events by detecting interference and acoustic signatures typical of lightning.
Notably, 54 of these events were linked to the strongest wind events recorded during the study, indicating that winds significantly contribute to Martian electrification.
In two encounters with dust devils alone, the spacecraft documented 16 events, suggesting the likelihood of additional, more distant discharges that may have escaped detection by the microphone.
These findings imply that the Martian atmosphere is particularly electrically active during localized dust activity, rather than during wider dusty seasons.
“On Earth, atmospheric electricity primarily results from charge accumulation in clouds and storms, which burst forth as lightning,” remarked Dr. Ricardo Hueso from the University of the Basque Country.
“Conversely, on Mars, atmospheric electricity is dry, generated through collisions between dust particles in whirlwinds and sandstorms, leading to much smaller electrical discharges compared to Earth.”
Dr. Agustín Sánchez Labega, also from the University of the Basque Country, noted: “Mars’ cold, dry, dusty environment features a thin atmosphere of carbon dioxide and can generate very strong winds, creating gusts, whirlwinds, and dust clouds.”
“These phenomena can form extensive storm fronts that stretch hundreds of kilometers and sometimes envelop the entire planet in dust.”
“Thus, we anticipate these once-elusive discharges to be particularly prevalent under such conditions.”
The authors concluded, “Our study raises many questions regarding the impact of natural electricity on the Martian atmosphere.”
For more details, check their paper, published in the Journal on November 26, 2025, in Nature.
_____
B. Chide et al. 2025. Triboelectric discharges detected during Martian dust events. Nature 647, 865-869; doi: 10.1038/s41586-025-09736-y
Solar Panel and Robotic Arm of NASA’s Phoenix Lander with Sample in Scoop
NASA/JPL-California Institute of Technology/University of Arizona/Texas A&M University
Mars might harbor a system of liquid water flowing beneath its icy surface. Similar to permafrost on Earth, which is theorized to have thin veins of liquid minerals, new models suggest these veins on Mars could be substantial enough to sustain life.
“For Mars, we’re constantly flirting with the edge of habitability. Initially, I theorized this study would reveal that adequate water wouldn’t exist, thus making microbial life impossible,” states Hannah Sizemore from the Planetary Science Institute in Arizona. “I was mistaken.”
Sizemore and her team analyzed Mars’ soil composition to estimate the amount of icy soil that might actually comprise liquid water and the dimensions of the channels through which it flows. Temperatures on Mars can plummet to -150°C (-240°F), challenging the existence of liquid water. While pure water freezes at 0°C, the presence of salts—widespread on Mars—can significantly lower the freezing point.
The research indicated that it is “surprisingly feasible” to find soil containing over 5 percent liquid water in channels exceeding 5 microns in diameter. This threshold was deemed necessary for a vein to be classified as habitable. “The largest veins we’re referencing are 10 times narrower than a fine human hair,” Sizemore elaborates. “Nonetheless, it’s a sufficiently expansive environment to host microorganisms, allowing for the transfer of nutrients and waste within the ecosystem.”
Based on soil data collected by NASA’s Phoenix spacecraft, which landed on Mars in 2008, these networks of waterways may be prevalent at latitudes above 50 degrees. Sizemore indicated that if life exists on Mars, liquid veins would be prime locations for investigation, proposing that “this is a site where one could land and excavate around 30 centimeters to collect samples.”
The primary concern regarding these veins as potential habitats is their temperature, which can be significantly below what most known life forms can endure. “However, we must exercise caution in applying the limits observed for terrestrial organisms to other life forms, as they do not necessarily define the survival limits for all life that could exist elsewhere,” states Bruce Jakosky from the University of Colorado Boulder. “Ultimately, this study and related research suggest that the existence of life near the Martian surface is not out of the question.”
NASA’s diligent rover has been investigating and sampling igneous fields and sedimentary rocks within the Ezero Crater, providing insights into the geological processes and intriguing characteristics of early Mars, while also searching for potential biological signatures. Upon entering Neretvavalis, on the western edge of Jezero Crater, the rover examined the distinct mudstone and con rock outcrops of the Bright Angel formation. A new paper published in the journal Nature details extensive geological, petrological, and geochemical studies of these rocks.
The impression of this artist shows how Mars looked about 4 billion years ago. Image credit: M. Kornmesser/ESO.
“Upon the rover’s arrival at the Bright Angel formation and while analyzing the local rocks’ composition, our team was notably surprised by their distinctiveness compared to previous findings,” stated Dr. Michael Tice, a geoscientist and astrobiologist at Texas A&M University.
“These findings offer evidence of chemical cycling that organisms on Earth can utilize to harness energy.”
“As we delved deeper, we observed phenomena that could easily be attributed to early Martian life, yet remain challenging to rationalize purely through geological processes.”
“Living organisms conduct chemistry that is naturally prevalent, provided there’s sufficient time and suitable conditions.”
“To optimize our understanding, the chemistry leading to these rocks necessitates either elevated temperatures or biological involvement, and we find no signs of high temperatures here.”
“Nonetheless, these results warrant experimentation and eventually lab studies of the samples collected to completely rule out non-biological explanations.”
The Bright Angel layer comprises mudstone (fine-grained sedimentary rocks composed of silt and clay) and water-laid sedimentary rocks featuring layered beds indicative of a lively environment with flowing rivers and stagnant water.
Employing various instruments from Perseverance, such as Sherloc and PIXL spectrometers, scientists identified organic molecules and small mineral arrangements likely formed through chemical processes related to redox reactions and electron transfers. On Earth, these processes are frequently driven by biological activities.
The most notable characteristics include small nodules and “reaction fronts” – referred to as “poppy seeds” and “leopard spots” by the rover team – consisting of iron phosphate (likely vivianite) and iron sulfide (probably greygeite).
These minerals typically arise in cold, water-laden settings and are frequently associated with microbial metabolism.
“The structural arrangement suggests that they formed through the redox cycling of iron and sulfur along with associated minerals,” Dr. Tice commented.
“On Earth, such formations often occur in sediments where microorganisms consume organic material and ‘breathe’ rust and sulfate. “
“Their existence on Mars provokes an intriguing question: Could a similar process have occurred there?”
The artist’s concept depicts the perseverance of NASA’s Mars Rover on the surface of the red planet. Image credit: NASA/JPL-Caltech.
The Sherloc instrument identified a Raman spectral feature known as the G-band, indicating the presence of organic carbon, in certain Bright Angel rocks.
The most substantial signal originated from a location called Apollo Temple, which exhibited high concentrations of both Vivianite and Greygeite.
“The concurrent presence of this organic matter and redox-sensitive minerals is quite compelling,” Dr. Tice noted.
“This implies that organic molecules might have facilitated the chemical reactions responsible for forming these minerals.”
“It’s crucial to recognize that ‘organic’ doesn’t invariably imply life creation.”
“This suggests the presence of numerous carbon-carbon bonds.”
“Alternative processes can yield organic compounds without biological involvement. The organic compounds identified here could have been synthesized either by or as a result of biological activity.”
“If they originated from an organism, decomposition through chemical reactions, radiation, or heat would have been required to yield the G-band we observe today.”
This research outlines two potential scenarios: Firstly, these reactions might be abiotic (driven by geochemical mechanisms) while microorganisms, similar to those on Earth, could have influenced these reactions.
Interestingly, although some features of the nodules and reaction fronts can be produced by non-biological reactions between organic matter and iron, established geochemical processes that can generate sulfur-related features tend to require relatively high temperatures.
“Every observation we’ve made regarding these rocks indicates that they haven’t been subjected to heat capable of producing leopard spots and poppy seeds,” Dr. Tice remarked.
“If that’s accurate, we must genuinely contemplate the possibility that such formations were created by bacteria-like life forms existing in the Martian lake sediments over 300 million years ago.”
Views of Perseverance path through Neretva Vallis and the formation of Bright Angels. Image credit: Hurowitz et al., doi: 10.1038/s41586-025-09413-0.
The research team underscores that while the evidence is not definitive proof of past life, the findings align with NASA’s criteria for potential biosignatures. This characteristic paves the way for further inquiries to ascertain the biological or non-biological origins.
Perseverance has collected core samples from a Bright Angel layer named Sapphire Canyon, which are currently housed in sealed tubes onboard the rover.
This sample is prioritized for future return to Earth in a prospective mission.
“Once we return this sample to Earth, we can investigate it using far more sensitive instruments than those we can deploy on Mars,” Dr. Tice explained.
“We could analyze the isotopic composition of organic materials, fine mineralogy, and conduct searches for microfossils if they exist.”
“More tests can also help determine the maximum temperatures these rocks were subjected to, and whether high-temperature geochemical processes are the most plausible explanations for any potential biological signatures.”
“The similarities between processes on Mars and Earth are indeed remarkable. However, there’s one crucial distinction.”
“It’s fascinating to note that life employs some of the same processes on both planets around the same epochs.”
“We observe signs of microorganisms in Earth’s rocks of similar ages where iron and sulfur interact with organic matter in comparable ways, but we don’t encounter the exact features seen in Mars’ ancient stones.”
Due to tectonic activities, the majority of Earth’s rocks have been altered significantly, making it unique and spectacular to witness this phenomenon on another planet.”
____
Ja Hurowitz et al. 2025. Redox-driven minerals and organic associations at Jezero Crater, Mars. Nature 645, 332-340; doi:10.1038/s41586-025-09413-0
This article is based on a press release provided by Texas A&M University.
Dakar, Senegal – the largest meteorite discovered on Earth – a 54-pound (25 kilograms) rock that fetched over $5 million at a New York auction last month, setting a world record.
However, in a West African nation where rusty red rocks have been excavated from the Sahara desert, authorities have initiated an investigation into what they describe as “illegal international trafficking,” suggesting it may have been smuggled from the country.
Here’s what you should know about meteorites and legal controversies:
How was it discovered
According to Sotheby’s, the rock, designated NWA 16788, was dislodged from the surface of Mars by a massive asteroid collision and journeyed 140 million miles (225 million kilometers) to Earth.
It was uncovered in the Sahara, northwest Niger by an unnamed meteorite hunter in November 2023, as per the auction house’s report. The identities of buyers remain undisclosed.
In the arid regions of the Sahara like Niger, meteorite hunting is on the rise. While meteorites can fall anywhere on Earth, the Sahara has emerged as a prime location for their discovery due to its climate, which is conducive to conservation.
Hunters often seek space rocks to sell to collectors and scientists. The most coveted and valuable meteorites are from Mars and the Moon.
As reported by the Heritage Academic Journal, the rock was sold to international dealers and eventually made it to a private gallery in Italy. Last year, a team of scientists from the University of Florence examined the rock to determine its structure and origins before it fell to Earth.
The meteorite was briefly showcased in Rome before appearing at the New York auction last month.
Why Niger is investigating
Following the sale, Niger raised concerns about how the meteorite was made available for auction.
Last month, the Niger government launched an inquiry into the discovery and sale of meteorites, stating that it resembles “illegal international trafficking.”
Last week, President Abdullah Hamanetiani halted the export of precious stones, semi-precious stones, and meteorites to ensure proper traceability.
In a statement to the Associated Press, Sotheby’s maintained that the meteorite was exported from Niger and transported in line with all applicable international regulations.
“In selling this item, all necessary documentation was obtained at each stage of the journey, consistent with best practices and the requirements of the involved countries,” the statement indicated.
Niger authorities did not respond to inquiries from the Associated Press.
What international law says
Patti Garstenblis, a cultural heritage attorney and expert on illegal trade, noted that rare minerals like meteorites are recognized as cultural property under the UNESCO Cultural Property Treaty, which both Niger and the United States have ratified.
However, Garstenbliss pointed out that Niger needs to establish ownership and that the meteorite was stolen.
“I doubt Niger could reclaim the meteorite if it wasn’t stolen and was properly declared upon entering the U.S.,” she stated to the Associated Press.
Paleontologist Paul Sereno, who has spent years uncovering dinosaur fossils in Niger’s Sahara, is advocating for the return of the nation’s cultural and natural heritage, including meteorites.
“When laws clearly state that rare minerals like meteorites are cultural artifacts, unique and valuable items cannot just be claimed without consideration for the country,” he told the AP.
“We are no longer in a colonial era,” he added.
In certain countries, including Morocco, a major source of meteoritic specimens for international markets, if an object is found on their territory, compensation is required. Nonetheless, due to the expansive desert regions and the informal trading networks, enforcement remains challenging.
Water is crucial for life, which is why researchers prioritize finding water sources when exploring other planets. Mars is of particular interest to astrobiologists due to evidence of historical water presence. The current surface of Mars is cold and arid, prompting scientists to investigate what happened to that past water. Studies have indicated that Mars has an active water cycle that produces clouds of water ice, but the existence of water on its surface remains unclear.
Recently, an international team of researchers employed high-resolution imaging and spectral photoanalysis to look for frost on Mars’ volcanoes. They analyzed around 4,200 images obtained using a technology known as color and stereo surface imaging technology from Cassis. This technology utilizes satellite imagery of Mars from the European Space Agency’s Trace Gas Orbiter. The researchers explained that they identified frost by searching for the blue wavelengths in blackcurrant data, as frozen surfaces reflect more brightly at these blue wavelengths of spectral light.
Through their analyses, the team located 13 frost regions across four volcanoes, including Olympus Mons, Seranius Solas, Ascleus, and Arciamontes. They observed images taken over a 12-hour period and noted that high frost concentrations appeared early in the morning on the edges and craters of Olympus Mons. In one crater alone, frost covered an area of about 4,500 km or 3,000 miles, akin to the size of Philadelphia. The researchers estimated that these frost deposits were quite thin, measuring around 10 microns thick, which is roughly one-tenth the width of a human hair.
Next, the team sought to determine if the frost was composed of water or carbon dioxide. Given that Mars’ atmosphere is predominantly carbon dioxide, it is possible for carbon dioxide to freeze. Similar to Earth, Mars has ice in its polar regions; the Martian polar ice caps consist primarily of carbon dioxide, with minor amounts of water. Thus, they theorized that the volcanic frosts could also contain frozen carbon dioxide.
The research team utilized Mars weather research and prediction models to calculate the surface temperature of a volcano over a 24-hour period. They determined that the minimum temperature was -190°F or approximately -120°C, which is too warm for carbon dioxide frost to form, as it typically requires surface temperatures below -200°F or -130°C. However, they proposed that these volcanic frost deposits are likely made of water, as they were found at -140°F or -95°C in the Martian atmosphere.
The researchers highlighted that these Martian volcanoes are among the tallest highland volcanoes in the solar system and located within the equatorial region of Mars. It’s generally not expected that water ice would form in equatorial volcanoes since the slopes and sides tend to be too warm for frost condensation. However, their climate model indicated that the unique topography of these volcanic craters created local weather patterns conducive to frost formation.
Finally, the team carried out further observations and climate model simulations of Olympus and Arciamontes to ascertain whether this frost can form solely during the day or throughout the night. They found that frost accumulated in both volcanoes during the early mornings of winter and spring but not in summer, indicating a seasonal pattern that might reflect variations in Martian temperatures.
The researchers concluded that Mars’ volcanoes produce about 150,000 tonnes, or 150,000,000 kilograms, of water frost daily. They suggested that this frost formation is likely influenced by seasonal atmospheric phenomena such as wind patterns and pressure changes. Studying these processes could help scientists determine the potential for life on Mars; nevertheless, they noted that additional research is needed to rule out direct volcanic water sources.
Sample analysis of Mars Instrument on NASA’s Curiosity Rover detected decane, anteca and dodecane molecules in Gale Crater samples.
This graphic shows the long chain organic molecules, decane, undercane, dodecane, and rover of curiosity from NASA. Image credit: NASA/Dan Gallagher.
“The main scientific goal of Curiosity is to quantitatively assess the possibility of Mars’ habitability in the past or present,” says Dr. Caroline Freissinet, researcher at Atmosphères ET Observation Spatiales at CNRS and Laboratoire.
“Sample analysis in the MARS (SAM) instrument suite on a rover is dedicated to this task by employing inventory of organic and inorganic compounds present on the surface of Mars as potential chemical biosignatures and investigating the nature of the conservation.”
Using SAM instruments, researchers analyzed molecules released from excavated mudstone samples called Cumberlands, collected in Yellowknife Bay, the geological layer of Gale Crater.
They were able to detect three long chain alkanes: decane (c)10htwenty two), unedecane (c11htwenty four), and dodecan (c12h26).
“These long carbon chains, which contain up to 12 consecutive carbon atoms, can exhibit similar characteristics to the fatty acids produced on Earth through biological activity,” the researchers said.
Dodecane represents the highest molecular mass organic molecule ever identified on the surface of Mars.
“Detection of long-chain alkanes shows various causes of organic matter and storage mechanisms in Cumberland samples,” the scientists said.
“Clays and sulfate minerals are expected to play an important role in this long-term storage.”
According to the author, the source of Mars’ long-chain alkanes remains uncertain.
“Laboratory experiments support sources from the saturated forms of linear chains, primary carboxylic acids, i.e. decano acids, dodecano acids, and tridecano acids, for decane, undecano and dodecano acids, respectively,” they said.
“Abiotic processes can form these acids, but are considered to be a universal product of biochemistry, on the ground and perhaps Mars.”
“The origin and distribution of these molecules therefore has great interest in searching for potential biosignatures on Mars.”
Survey results It will be displayed in Proceedings of the National Academy of Sciences.
____
Caroline Freecinet et al. 2025. Long chain alkanes are preserved in the mudstones of Mars. pnas 122 (13): e2420580122; doi: 10.1073/pnas.2420580122
Crystals within a Martian meteorite suggest Mars may have had abundant hydrothermal water when the rock formed 4.45 billion years ago.
The rock, called Black Beauty, was blown into space by an impact on Mars' surface and eventually crashed into the Sahara desert.
We already know a lot about Mars from the study of a meteorite discovered in Morocco in 2011, officially known as Northwest Africa 7034.
aaron cabosy Researchers at Curtin University in Perth, Australia, have been studying the tiny fragments, which contain zircon crystals 50 micrometers in diameter, for years.
Kavosie describes Black Beauty as “a rock that looks like a trash can.” Because it was formed by hundreds of pieces smashed together. “This is a great buffet of Martian history, with a mix of very old and very young rocks,” he says. “But much of the debris it contains belongs to some of the oldest rocks on Mars.”
The fragments studied by Kavosy and his team had crystallized in magma beneath Mars' surface. When they tested the zircons, they also found, unusually, that the elements iron, aluminum, and sodium were arranged in thin, onion-like layers.
“We wondered where else could we find elements like this in zircon crystals,” Kabosie says. The answer, he says, lies in South Australia's gold ore deposits. The zircon crystals there were nearly identical to those from Mars, including the same unusual combination of additional elements.
“This type of zircon is known to form only in places where hydrothermal processes or hydrothermal systems are active during igneous activity,” Kabosie says. “The hot water facilitates the transport of iron, aluminum, and sodium into the crystals as they grow layer by layer.”
Zircon has been exposed to multiple large-scale traumas, including the impact of an ancient collision and then another meteorite that hit the surface of Mars 5 to 10 million years ago and blasted Black Beauty into space have experienced. Despite these violent events, the rock's crystal structure is still intact at the atomic scale.
The lack of radiation damage means the extra elements were part of the crystal from the beginning, rather than being contaminated later, Kavosy said.
Eva Scherer Researchers at Stanford University in California believe that if this rock really formed in the presence of hydrothermal fluid and magma beneath the surface of Mars, water vapor entered the Martian atmosphere before rivers and lakes formed. This suggests that it may have been released.
“We're at a very old time, 4.5 billion years, when Mars was formed,” Scherrer said. “So this would be the earliest evidence of water behavior on Mars.”
Eleven million years ago, an asteroid hit Mars, sending debris flying through space. One of these masses eventually crashed into Earth. During initial investigation of this object, lafayette meteoritescientists discovered that it interacted with liquid water while on Mars. Now, researchers from the US and UK have determined the age of minerals in meteorites that formed when liquid water was present.
The Lafayette meteorite was scraped off the surface of Mars and then spent about 11 million years flying through space. It finally ended up in a drawer at Purdue University in 1931 and has been teaching scientists about Mars ever since. Image credit: Purdue Brand Studio.
A meteorite is a solid time capsule from a planet or celestial body in the universe.
They carry bits of data that can be unlocked by geochronologists.
They are distinguished from rocks you might find on Earth by the crust they form as they fall into the atmosphere, often forming a fiery portal visible in the night sky.
“We can identify meteorites by studying what minerals are in them and the relationships between these minerals,” said researcher Dr. Marissa Tremblay. states. purdue university.
“Meteorites are often denser than Earth's rocks, contain metals, and are magnetic.”
“We can also look for things like the fusion crust that forms when we enter Earth's atmosphere.”
“Finally, we can use the chemical properties of meteorites (particularly their oxygen isotope composition) to determine which planet they came from or what type of meteorite they belong to. ”
According to the authors, some Martian meteorites, such as the 0.8 kg Nacritite meteorite called the Lafayette meteorite, contain minerals that were formed by interaction with liquid water while on Mars. That's what it means.
“So by dating these minerals, we can tell when in Mars' geological past there was liquid water on or near the surface of Mars,” Tremblay said. .
“We dated these minerals in the Martian meteorite Lafayette and found that they formed 742 million years ago.”
“At this point, we don't think there was an abundance of liquid water on the surface of Mars.”
“Instead, we believe this water comes from melting nearby underground ice called permafrost, and that permafrost thaw is caused by magmatic activity that continues to occur regularly on Mars. ”
Researchers say the age derived from the timing of water-rock interactions on Mars is robust and the chronometer used is not affected by events that happened to the Lafayette meteorite, which changed in the presence of water. It was proved that.
“This age could be due to the impact of the Lafayette meteorite being ejected from Mars, the heating Lafayette experienced during its 11 million years floating in space, or the heating Lafayette experienced when it fell to Earth and burned up a bit. “in Earth's atmosphere,'' Dr. Tremblay said.
“But we were able to demonstrate that none of these things affected the chronology of water quality changes in Lafayette.”
“This meteorite has unique evidence that it interacted with water,” said Dr. Ryan Ickert, also of Purdue University.
“The exact date of this is controversial, and our publication dates from a time when water existed.”
“We know this because after this meteorite was ejected from Mars, it was bombarded with cosmic ray particles in space, producing specific isotopes at Lafayette,” Tremblay said. said.
“Many meteoroids are produced by impacts on Mars and other planets, but only a handful end up falling on Earth.”
of findings Published in this month's magazine Geochemical perspective letter.
_____
MM Tremblay others. 2024. Dating recent water activity on Mars. Letter from a geochemical perspective 32;doi: 10.7185/geochemlet.2443
Martian “spiders” are small, dark, spider-shaped formations up to 1 km (0.6 miles) in diameter. The leading theory is that they form when spring sunlight hits a layer of carbon dioxide that builds up during the dark winter months. In a new experiment, a team of NASA scientists has recreated these formation processes for the first time, simulating Martian temperatures and air pressure.
Examples of “Keefer Zoo” features proposed to have formed by seasonal CO2 sublimation dynamics on Mars: (a) a “skinny” spider within layered deposits in Antarctica, (b) a dark spot on a layer of translucent CO2 slab ice covering a group of “fat” spiders in an “Inca city” on Mars, (c) a “fried egg” showing a ring of dark dust surrounded by a bright halo, (d) patterned ground within high Antarctic latitudes with dark directional fans and some bright white fans indicating wind direction, (e) a bright halo surrounding a Swiss cheese depression, (f) a “lacey topography”, a type of patterned ground suggested to be polygonal patterned ground that was later scraped and eroded by surface-flowing CO2 gas from the Keefer model. Image credit: HiRISE/NASA Jet Propulsion Laboratory/University of Arizona.
Today, Mars is a dynamic planet with a rich variety of surface changes, despite its thin atmosphere and cold climate.
In winter, most of Mars' mostly carbon dioxide atmosphere accumulates on the surface as frost.
In spring, it sublimates and takes on forms never seen on Earth.
These include dark Dalmatian spots, directional alluvial fans, “fried eggs”, grooves which may have dark finger-like flows or light “halos” in spring, dendritic “spiders”, sand grooves in active dunes and growing dendritic valleys.
These features have been detected in the loose material around the Antarctic and in the inter-dune material towards the mid-Antarctic latitudes, although some smaller phenomena have also been detected in the Arctic.
Many of these features make up the so-called “Kiefer zoo,” or collection of surface expressions. Explained It was first published in 2003 and was proposed to be produced by the solid-state greenhouse effect.
“In the Kiefer model, sunlight penetrates a translucent ice sheet in spring, trapping thermal radiation and heating the topsoil beneath the ice, causing the impermeable sheet to sublime from beneath,” explained Dr. Lauren McKeown of NASA's Jet Propulsion Laboratory and her colleagues.
“Through this process, the spiders are thought to be caused by high-velocity gases scraping away topsoil beneath the ice sheet, littering the ice surface with fan and patchy variations that are then deposited by dust and gas plumes.”
The study authors were able to create a complete cycle of the Kiefer model in the lab and confirm the formation of several types of Kiefer zookeeper features.
“The greatest challenge in conducting the experiment was replicating the conditions found on the polar surface of Mars, namely the extremely low air pressure and temperatures of minus 185 degrees Celsius (minus 301 degrees Fahrenheit),” the researchers said.
“To do this, we used a liquid nitrogen-cooled test chamber, the Dirty Under Vacuum Simulation Chamber for Icy Environments (DUSTIE).”
“In our experiments, we cooled a Martian soil simulant in a container submerged in a bath of liquid nitrogen.”
“We placed it in the Dusty Chamber, where the air pressure was lowered to the same as in the southern hemisphere of Mars.”
“Carbon dioxide gas was then released into the chamber, where it condensed from the gas into ice over a period of three to five hours.”
“It took a lot of trial and error before we found the right conditions to make the ice thick and clear enough for the experiment to work.”
“Once we have ice with the right properties, we place a heater in the chamber underneath the simulant to heat it up and crack the ice.”
“We were thrilled when we finally saw plumes of carbon dioxide gas coming out of the powdered simulant.”
a paper The explanation for these experiments is Planetary Science Journal.
_____
Lauren E. McKeon others2024. Laboratory-scale investigation of the Kiefer Model of Mars. Planet Science Journal 5, 195;doi:10.3847/PSJ/ad67c8
This image of an Inca city on Mars was taken on February 27, 2024 by the high-resolution stereo camera on board ESA’s Mars Express spacecraft. Image credit: ESA / DLR / FU Berlin.
“The Martian ‘spiders’ are not actual spiders, but form when spring sunlight falls on layers of carbon dioxide deposited during the dark winter,” said a member of the Mars Express team.
“Sunlight turns the carbon dioxide ice at the bottom of the layer into gas, which then accumulates and breaks through the ice sheet above.”
“During Mars’ spring, the gas explodes, dragging black material down to the surface as it progresses and shattering layers of ice up to a meter thick.”
“The resulting gas, laden with black dust, erupts through cracks in the ice in the form of tall fountains and geysers, before falling down and sinking to the surface.”
This creates a dark spot 45 m to 1 km (148 to 3,280 ft) in diameter.
This same process carves a distinctive “spider-shaped” pattern beneath the ice. Therefore, these black spots are evidence that a spider may be lurking underneath.
“Dark spots can be seen throughout the Mars Express image. But most of them can be seen as small specks in the dark region on the left, located just on the outskirts of a part of Mars called Inca City.” said the researchers.
“The reason for this name is no mystery: the network of linear, almost geometric ridges recalls Inca ruins.”
More formally known as Angustus Labyrinth. Inca City was discovered in 1972 by NASA’s Mariner 9 spacecraft.
“We still don’t know exactly how Inca cities formed. Sand dunes may have turned to stone over time,” the scientists said.
“Perhaps materials such as magma or sand are seeping through fractured sheets of Martian rock. Alternatively, the ridges could be ‘eskers,’ tortuous structures associated with glaciers.”
“The ‘walls’ of Inca cities appear to be part of a larger circle, 86 km (53.5 miles) in diameter.”
Scientists suspect that Inca City is located inside a large crater formed when rocks from space collided with the planet’s surface.
“This impact may have caused the fault to ripple in the surrounding plains, which was then filled with rising lava and then worn away over time,” the researchers said.
This website uses cookies so that we can provide you with the best user experience possible. Cookie information is stored in your browser and performs functions such as recognising you when you return to our website and helping our team to understand which sections of the website you find most interesting and useful.
Strictly Necessary Cookies
Strictly Necessary Cookie should be enabled at all times so that we can save your preferences for cookie settings.
