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A planet’s history is told in its ancient rock. Earth’s oldest rocks are in the Canadian Shield, Australia’s Jack Hill, the Greenstone Belts in Greenland, and a handful of other locations. These rocks hold powerful clues to our planet’s history. On Mars, the same holds true.

That’s why NASA’s Perseverance rover is revisiting some of them.

Perseverance is exploring Jezero Crater, an ancient paleolake. Its thick layer of sediments may contain evidence of ancient life on Mars. Every crater has a rim, and Perseverance’s current campaign involves studying the rim. The crater rim is different than the sediments. It’s made of ancient rock uplifted and exposed on the surface by the ancient impact that created Jezero.

On Earth, geologists regularly study rock that has made itself easy to examine by coming up from the deeper crust and presenting itself. The same thing happens on Mars, though impacts do the lifting, not plate tectonics. Perseverance is studying the rocks on the crater rim in its current Crater Rim Campaign. The location it’s exploring is an exposed outcrop named Tablelands.

This image shows Perseverance’s landing ellipse (green circle) and the different regions in the Jezero Crater. The rover is currently exploring the crater rim, shown in purple. Image Credit: NASA/JPL-Caltech/USGS/University of Arizona

One type of rock that can teach us a lot about Mars’ ancient history is serpentine. It’s common on Earth and Mars and forms in the presence of water. Its presence on Mars is some of our strongest evidence that the planet was once wet.

Perseverance sampled Silver Mountain, a rock in the Tablelands. The rover used its abrasion tool on its robotic arm to create a fresh surface it could analyze. That analysis showed Silver Mountain is rich in pyroxene, a type of silicate found in almost every igneous and metamorphic rock. The rover also collected a core.

After that, it visited a rock named Serpentine Lake that showed telltale signs of serpentine. Perseverance used its abrasion tool to clean the rock for a detailed investigation. Serpentine Lake has an intriguing texture, described in a press release as “cookies and cream.” It’s also high in serpentine and other minerals that form in the presence of water.

Perseverance used its Scanning Habitable Environments with Raman and Luminescence for Organics and Chemicals (SHERLOC) instrument to examine the Serpentine Lake rock. The rock shows a high concentration of serpentine, indicating that it was exposed to water for a long time, a hint of Mars’ potential ancient habitability. Its unusual texture also hints at complex geological processes. Image Credit: NASA/JPL-Caltech

After that, Perseverance doubled back to revisit a rock named “Cat Arm Reservoir.”

It was the first rock the rover studied on the canyon rim. The rover analyzed its composition and detected coarse pyroxene and feldspar crystals, indicating an igneous origin. Unfortunately, Perseverance’s sample tube was empty. Sometimes, the rock the rover tries to sample is weak and turns to dust. This is rare, but it did happen during the rover’s very first sampling attempt, and it happened again with Cat Arm Reservoir.

This image from NASA’s Perseverance Location Tracker shows the rover’s convoluted path as it explores the rim of Jezero Crater. Image Credit: NASA/JPL

Perseverance travelled a small distance and tried to collect a core sample from Cat Arm Reservoir again. That attempt also failed. Then the rover chose a different spot nearby named “Green Gardens” and successfully collected a core sample. It’s next to the abrasion patch on Serpentine Lake.

NASA’s Mars Perseverance rover acquired this image of the area in front of it. It shows the Serpentine Lake abrasion patch on the right-hand side of the rock, with the Green Gardens sampling location on the left. The rover used its onboard Front Right Hazard Avoidance Camera A and captured the image on Feb. 16, 2025 (sol 1420, or Martian day 1,420 of the Mars 2020 mission) at the local mean solar time of 16:45:19. Image Credit: NASA/JPL-Caltech

Like the Serpentine Lake rock, Green Garden is also green, which is a characteristic of the mineral serpentine. Serpentine forms in the presence of water when hydrothermal vents alter ultramafic rocks. Scientists are interested in these minerals because their structure and composition can reveal the history of water on Mars. On Earth, serpentine rock also hosts microbial life, so the same may have been true on Mars. Unfortunately, it’s not clear how much evidence of this life can be preserved.

Perseverance’s “Green Garden” core sample was collected on February 17th. Image Credit: NASA/JPL-Caltech

Perseverance will spend some more time exploring the Tablelands outcrop. It may re-examine the Serpentine Lake abrasion patch and analyze the debris from the Green Gardens drilling and coring. This could take a couple of weeks.

Next on its agenda is “Broom Point,” further down the crater rim. Broom Point contains a spectacular formation of layered rock, which is also intriguing to scientists.

Mars’ ancient history is told in its ancient rocks, but it’s impossible to know in advance which rock holds which clues and how everything will fall into place.

We don’t know what Perseverance will discover about Broom Point. But the rock will tell us something. It always does.

• Press Release: Cookies, Cream, and Crumbling Cores
• Press Release: Gardens on Mars? No, Just Rocks!
• Press Release: Assessing Perseverance’s First Sample Attempt
• NASA: Where is Perseverance?

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Data from the Chinese rover Zhurong is adding to the pile of evidence for oceans on ancient Mars. For a year, this little craft traveled over nearly two kilometers of the Martian surface and made radar scans of buried natural structures that look like ocean shorelines.

Zhurong’s ground-penetrating radar (GPR) looked under the surface to a depth of 80 meters. There, the radar instrument found thick layers of material similar to beach deposits on Earth. The best way to create such formations is by wave action stirring up and depositing sediments along the shore of an ocean. If these findings stand, they’ll provide a deeper look into Mars’s ancient warm, wet past, and the existence of long-gone seas.

Map of Utopia Planitia showing the landing site of the Zhurong rover and four proposed ancient shorelines. The landing site is about 280 kilometers north of and some 500 meters lower in elevation than the northern hypothesized shorelines. In its traverse, Zhurong traveled south from its landing site, toward the ancient shorelines. Courtesy: Hai Liu, Guangzhou University, China Figuring Out Mars Shorelines

“The southern Utopia Planitia, where Zhurong landed on May 15, 2021, is one of the largest impact basins on Mars and has long been hypothesized to have once contained an ancient ocean,” said Hai Liu, a professor with the School of Civil Engineering and Transportation at Guangzhou University and a core member of the science team for the Tianwen-1 mission, which included China’s first Mars rover, Zhurong. “Studying this area provides a unique opportunity to investigate whether large bodies of water ever existed in Mars’ northern lowlands and to understand the planet’s climate history.”

At first, scientists considered lava flows or dunes to explain the structures Zhurong measured. But, their shapes say otherwise. “The structures don’t look like sand dunes. They don’t look like an impact crater. They don’t look like lava flows. That’s when we started thinking about oceans,” said Michael Manga, a University of California, Berkeley, professor of earth and planetary science. He was part of Hai’s team that recently published a paper about Zhurong’s findings. “The orientation of these features are parallel to what the old shoreline would have been. They have both the right orientation and the right slope to support the idea that there was an ocean for a long period of time to accumulate the sand-like beach.”

Digging into the Past

Aside from their meteorological and geological value, the presence of these shoreline structures also implies that Mars’s ancient oceans were ice-free. “To make ripples by waves, you need to have an ice-free lake. Now we’re saying we have an ice-free ocean. And rather than ripples, we’re seeing beaches,” Manga said. That tells us Mars was a warmer world—at least for a while. Rivers could well have flowed across the surface, contributing rocks and sediments along the shorelines. And, of course, there are structures that imply the presence of oceans. On Earth, oceans provide life habitats and there’s no reason to think that Mars oceans couldn’t have done that, too.

“The presence of these deposits requires that a good swath of the planet, at least, was hydrologically active for a prolonged period in order to provide this growing shoreline with water, sediment, and potentially nutrients,” said co-author Benjamin Cardenas, an assistant professor of geosciences at The Pennsylvania State University (Penn State). “Shorelines are great locations to look for evidence of past life. It’s thought that the earliest life on Earth began at locations like this, near the interface of air and shallow water.”

Shoreline Evidence for Changes on Mars

As far back as Viking, scientists had images showing what looked like irregular shorelines and flow features on the surface. Those features implied bodies of water and flowing rivers. Other missions returned images and data showing ponded areas where smaller bodies of water existed. More recent missions returned images of regions scoured and changed by catastrophic floods. The shoreline features imply that oceans existed.

We know today that Mars’s surface no longer hosts bodies of water. In the past, much of it escaped to space along with Mars’ atmosphere. But some water also went underground and remains there as ice deposits. And, some combined with rocks to form new minerals. Other geological features seem to point to the existence of Martian oceans, like the shorelines Zhurong and Viking measured.

Schematic showing how a series of beach deposits would have formed at the Zhurong landing site in the distant past on Mars (left) and how long-term physical and chemical weathering on the planet altered the properties of the rocks and minerals and buried the deposits. Courtesy: Hai Liu, Guangzhou University, China

However, the irregular shape of those shorelines continued to intrigue planetary scientists. That’s because they didn’t exactly look like shorelines like we see along Earth’s oceans, which are level. In 2007, Manga came up with the idea that the shapes of the shorelines were altered by changes in the planet’s rotation. Why did that happen? Blame it on volcanoes in the Tharsis region. Some 4 billion years ago volcanic activity there built up a huge bulge. That eventually messed with the planet’s rotation. “Because the spin axis of Mars has changed, the shape of Mars has changed. And so what used to be flat is no longer flat,” Manga explained.

If the findings hold up, the buried shorelines tell a compelling story of the last days of oceans on Mars. Based on the team’s paper, that water appears to have lasted tens of millions of years. As it disappeared and the climate dried up, wind-blown regolith covered the shorelines that Zhurong measured.

For now, the Zhurong data provides a look into shoreline deposits that are pristine—but buried under the subsurface. “There has been a lot of shoreline work done,” said Cardenas, “but it’s always a challenge to know how the last 3.5 billion years of erosion on Mars might have altered or completely erased evidence of an ocean. But not with these deposits. This is a very unique dataset.”

For More Information

Ancient Beaches Testify to Long-ago Ocean on Mars
Ancient Ocean Coastal Deposits Imaged on Mars

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New information is pushing Asteroid 2024 YR4 off of our front pages. Initial estimates gave it a 2.8% chance of striking Earth in 2032. Now, the European Space Agency says the chance of it striking our planet is down to a paltry 0.001%.

Scientists dislike expressing things in absolute terms because Nature can make fools of us all, so this is as close to zero as it’s likely to get.

2024 YR4 was discovered by the Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in Chile a couple of days after Christmas. ATLAS is an early-warning system for smaller asteroids. When it detected the asteroid on December 27th, 2024, it sent out an alert. Follow-up observations indicated the asteroid’s impact probability was greater than 1%, and that triggered our planetary defence response, which at this point consists of a greater effort to understand the rock and its trajectory.

It’s easy to get used to these asteroid warnings. However, it’s a bad idea to ignore the threat they pose. 2024 YR4 is not very large, only between 40 to 90 metres (130 to 300 ft) in diameter. Its small mass doesn’t mean it’s not dangerous. An asteroid that large can cause serious damage in a populated area. Earth has been struck many times in the past, and there are more impacts in its future.

More worryingly, follow-up observations at first showed the asteroid’s impact probability rising. At its highest rating on 18th February, it had a 2.8% chance of striking Earth. The spike of concern was dulled the next day when observations with the ESO’s Very Large Telescope cut that number in half. People unfamiliar with space, Earth, and asteroids have asked why there’s so much uncertainty. The simple answer is that everything in space is moving. The object is also tiny and dark.

The Very Large Telescope is one of the world’s most advanced telescopes and even it could barely see the asteroid, as the GIF below shows.

via GIPHY

In the two months following its detection, the ESA’s Near-Earth Object Coordination Centre—along with other institutions—monitored the asteroid. More data is better data in this case, and observations allowed astronomers to refine its orbit to determine how much of a threat it posed.

2024 YR4 follows an elliptical orbit around the Sun and crosses Earth’s path, making it a near-Earth Object (NEO). It takes almost four years to complete an orbit, and its last perihelion was on 22 November 2024. Its closest approach to Earth was on Christmas, two days before its discovery. At that time, it came to within 830,000 km of Earth. In December 2028, it will make its next closest approach at just more than 8 million km of Earth. Unfortunately, between this April and leading up to the next approach, none of our ground-based telescopes will be able to see it.

One problem in determining the impact threat is that everything in space is moving. Nothing is still. So, each time the asteroid comes near the Earth or the Moon, the gravity from both bodies has a chance of changing 2024 YR4’s orbit. These are called gravitational keyholes, and they complicate efforts to determine its orbit.

This rising and then falling impact probability is an established pattern in asteroid detection and monitoring. At first, there’s more uncertainty, but as astronomers continue to observe it, uncertainty is reduced.

What it boils down to is this: We spotted another small yet potentially dangerous rock with a chance to strike Earth. We watched it and saw that its chance of striking us shrank. Now, the rock will disappear into the blackness of space for three years.

Where does that leave us?

Each time another asteroid approaches, it triggers concern about protecting Earth. Should we launch a nuke and blow it to pieces? How about a kinetic impactor to change its orbit slightly? How about evacuating people from the impact zone?

We’re developing ways to protect the planet. NASA’s DART (Double Asteroid Redirection Test) showed that a relatively small mass can deter an approaching asteroid. Nukes are not needed and, in fact, can create an unpredictable shower of debris.

This artist’s illustration shows the ejection of a cloud of debris after NASA’s DART spacecraft collided with the asteroid Dimorphos. Credit: ESO/M. Kornmesser

One proposal for asteroid redirection envisions kinetic impactors waiting to be launched on short notice. They can be at a Lagrange point or possibly on the lunar surface, on standby until needed. The more advance notice we have, the smaller the kinetic mass needed to deter an asteroid.

The main effort right now is centred on finding all dangerous asteroids and constraining their orbits. The upcoming Vera Rubin Observatory will detect many asteroids and will help us identify which ones are hazardous.

The type of massive asteroid that rocked the dinosaurs is increasingly unlikely. It was between 10 and 15 km in diameter, and large asteroids like it tend to remain stable in the asteroid belt. But the smaller ones in the decameter size range are more likely to be perturbed out of their orbits and become NEOs. It’s those ones we really have to worry about.

NASA’s “Eyes on Asteroids” site maps the known Near-Earth asteroids (NEAs) and shows the population of these objects. Some are parent bodies of meteorites found on Earth. Courtesy NASA.

Asteroids are like pandemics. There’s always another one in the future. It’s simply nature. The danger from this one seems to have diminished, but another one will eventually come close.

Though the danger posed by 2024 YR4 has diminished, the overall threat posed by the asteroid population remains the same. In a sense, it’s not about any individual asteroid. It’s about our understanding of the risks in our space environment and how we can protect ourselves and Earth.

We’re not fully prepared to deflect an incoming asteroid if necessary, but we’re working towards it. In the meantime, get used to the occasional news article about asteroids with tiny yet real chances of striking Earth. 0.001% is tiny, but it’s not zero.

The post As Expected, the Threat from 2024 YR4 has Essentially Dropped to Zero appeared first on Universe Today.

Neutron stars are stellar remnants. Composed of dense nuclear material, they all have strong magnetic fields. But the magnetic fields of some neutron stars can be a thousand times stronger. They are known as magnetars, and we aren’t entirely sure how they generated such powerful magnetic fields. But a new study in Nature Astronomy reveals some clues.

The general thought has been that magnetars create their fields through some type of dynamo process. This is where a flow of magnetic material generates a magnetic field. Since the flow is driven by heat convection, it can power strong fields. Earth’s magnetic field is unusually strong for a planet of its size and is powered by the convection of iron in its core. However, the core of a neutron star is made of nucleons, not atoms, so it is difficult to determine a specific dynamo process for magnetars.

For this study, the team wanted to understand what are known as low-field magnetars. These are magnetars that have weaker magnetic fields than most magnetars, but still generate bursts of X-rays and gamma rays. Most magnetars are identified by their high-energy emissions, since it takes intense magnetic fields to create such powerful bursts. Low-field magnetars shouldn’t have a strong enough field to create such bursts, but they sometimes do. This would suggest that at times their magnetic fields become intense. The question is how.

To answer this question, the team ran computer simulations of several dynamo models, looking for one that best fit the observational data. They found that the best fit involved what’s known as the Tayler–Spruit dynamo. This dynamo is well known in stellar models and involves the differential rotation of a stellar core. Stars don’t rotate as a single rigid object. Instead, different latitudes of a star rotate at slightly different rates. This is likely caused by a fast-rotating core, which can produce the Tayler–Spruit dynamo.

The authors demonstrated that as a low-field magnetar forms, the supernova that created the magnetar transfers angular momentum to its core, thus creating a differential rotation. Through the Tayler–Spruit dynamo, this can create bursts of intense magnetic fields that power the X-rays and gamma rays we observe from these stars. This process is likely unique for low-field magnetars, as opposed to traditional magnetars that generate their magnetic fields in other ways.

Reference: Igoshev, Andrei, et al. “A connection between proto-neutron-star Tayler–Spruit dynamos and low-field magnetars.” Nature Astronomy (2025): 1-11.

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Well that’s ruined all my lectures! I’ve spent years talking about space and a go to fact is the red colour of Mars. It’s been long believed that it was caused by the same chemical process that creates rust on Earth, a new paper suggests this is not the case! The team of researchers simulated conditions of Mars in a lab and now think a chemical called ferrihydrite, an iron oxide that contains water. It now looks like the planet’s characteristic red colour is due to a time when Mars was covered in water! 

Mars, often called the Red Planet is the fourth planet from the Sun. With a thin atmosphere composed mostly of carbon dioxide, Mars features a stark landscape of vast plains, huge volcanoes including Olympus Mons (the largest in our solar system), and deep canyons like Valles Marineris. Its surface has evidence of ancient rivers and lakes, suggesting Mars once had conditions that could have been suitable for microbial life. Its extreme temperature changes and frequent global dust storms are typical of this harsh world. 

Mars seen before, left, and during, right, a global dust storm in 2001. Credit: NASA/JPL/MSSS

The distinctive red colour goes back centuries; the ancient Egyptians called Mars ‘Her Desher’ which translates to ‘the Red One’, the Romans named it after the God of war and the Chinese called it ‘the fire star.’ Even Babylonian records that go back to 2000 BC noted its red colour. In 1610, when Galileo first observed Mars through a telescope, he confirmed its planetary nature but also noted a more red/brown hue. This was largely due to the poor quality optics of the day and it wasn’t until optics improved that its red colour was observed in all its glory.

A bust of Galileo at the Galileo Museum in Florence, Italy. The museum is displaying recovered parts of his body. Credit Kathryn Cook for The New York Times

A team of researchers led by Dr Adomas Valantinas from Brown University in USA have published a paper in Nature Communications that has analysed the red colouration of Mars and challenge the common view that it’s a rust like material that is responsible. They used data from a number of different Mars missions from NASA’s Reconnaissance Orbiter to ESA’s Mars Express and ExoMars (which has the Colour and Stereo Surface Imaging System onboard.) The data from the orbiters was supported by data from various rovers too and further supplemented by analysis of artificial Mars-like materials in a laboratory.

An artist’s illustration of the Mars Express Orbiter above Mars. Its MARSIS instrument has been updated so it can study the moon Phobos. Image Credit: Spacecraft: ESA/ATG medialab; Mars: ESA/DLR/FU Berlin, CC BY-SA 3.0 IGO

The analysis, which included experiments and measurements at the University of Grenoble, Brown University and the University of Winnipeg revealed the presence of Ferrihydrite. Not only was it present in the Martian dust, it seemed to be widespread across the Martian landscape. Ferriydrite is an oxyhydroxide mineral (one that contains oxygen, hydrogen and at least one metal.)

The widespread discovery of ferrihydrite on in Martian dust helps us to understand more about the geological history of Mars and its potential habitability. The existence of the ferrihydrite tells us that there were once cooler, wet conditions on Mars since that is a neccessity for the formation of the mineral. It’s an exciting discovery because its one more reason to believe that Mars was once a hospitable world. 

The team are keen to learn more and are now waiting for Martian samples to study directly and for that, they are waiting for the Perseverance rover. It has been systematically collecting core samples of Martian soil from the Jezero Crater and storing them in titanium tubes ready for transport home. Once the team has these, they will be able to check whether their theory about ferrihydrite is correct.

Source : Why Mars could be red

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According to Darwin, life on Earth may have first appeared in warm little ponds. This simple idea is also a cornerstone in our search for the origin of life. The ponds were rich in important chemicals, and when lightning struck, somehow, it all got going.

If the idea is correct, the same thing may have happened on Mars. If it did, and if fossilized evidence of microbes on the planet exists, a new laser could find it.

We may never know exactly how life started. It appeared to start about 4 billion years ago on Earth, confined to water for about 3 billion, until our planet developed a UV-blocking ozone layer.

If life ever appeared on Mars, it also likely occurred billions of years ago when the planet was warm and wet. There’s a strong possibility that it was also confined to water for a long time. If it did, then ancient sediments could hold fossilized evidence of microbes.

NASA’s Perseverance rover landed in Jezero Crater, an ancient paleolake with deep sediments, in an attempt to detect evidence of ancient life. Jezero also contains an ancient river delta, an excellent place for sediments to collect and potentially preserve microbial evidence.

Perseverance carries a laser as part of its Supercam instrument, an improved version of MSL Curiosity’s Chemcam instrument and laser. Supercam analyzes rocks and soils and searches for organic compounds that are biosignatures of ancient microbial life.

Now, scientists are working on a new laser that could detect microbial fossils on Mars. The device will examine gypsum deposits for signs of these fossils. The device has already been tested in Mars-analogue gypsum deposits in Algeria.

The method is explained in new research published in Frontiers in Astronomy and Space Sciences. Its title is “The search for ancient life on Mars using morphological and mass spectrometric analysis: an analog study in detecting microfossils in Messinian gypsum.” The lead author is Youcef Sellam, a PhD student at the Physics Institute at the University of Bern.

“Our findings provide a methodological framework for detecting biosignatures in Martian sulfate minerals, potentially guiding future Mars exploration missions,” said Sellam. “Our laser ablation ionization mass spectrometer, a spaceflight-prototype instrument, can effectively detect biosignatures in sulfate minerals. This technology could be integrated into future Mars rovers or landers for in-situ analysis.”

Sellam is referring to sulphate minerals, including gypsum, left behind when bodies of water dry up. The minerals precipitate out and collect as deposits, as has happened repeatedly in the Mediterranean Sea during the Messinian salinity crisis.

“The Messinian Salinity Crisis occurred when the Mediterranean Sea was cut off from the Atlantic Ocean,” said Sellam. “This led to rapid evaporation, causing the sea to become hypersaline and depositing thick layers of evaporites, including gypsum. These deposits provide an excellent terrestrial analog for Martian sulfate deposits.”

We know something similar happened on Mars because gypsum deposits are plentiful. Since these deposits form rapidly, there’s a chance for fossils to be preserved before they can decompose.

“Gypsum has been widely detected on the Martian surface and is known for its exceptional fossilization potential,” explained Sellam. “It forms rapidly, trapping microorganisms before decomposition occurs, and preserves biological structures and chemical biosignatures.”

Gypsum deposits on Earth have been extensively studied for evidence of microbes.

These images, taken from separate research into gypsum deposits on Earth, show different types of microbial colonization in gypsum deposits. Panels B and C, for example, show zones rich in algal cells. More info here. Image Credit: Jehlicka et al. 2025.

“Prokaryotic communities are often found dwelling within modern evaporites, such as gypsum, forming in sabkhas, lacustrine, and marine terrestrial sediments,” the authors explain in their paper. “They mainly participate in carbon, iron, sulphur, and phosphate biogeochemical cycles, extracting water and using various survival strategies to avoid ecological stresses. Consequently, investigating these fossil filaments may enhance our comprehension of the cryptic conditions that led to the formation of the Primary Lower Gypsum unit during the Messinian Salinity Crisis, the biosignature preservation potential of gypsum, and the possible preservation of such fossils in ancient, hydrated sulphate deposits on Mars.”

Detecting evidence in Earth’s gypsum deposits is relatively simple. However, doing it on Mars is rife with challenges. Since scientists already know that Mediterranean gypsum deposits hold evidence of life, Sellam went to test the method there.

Sellam and his co-researchers tested their method at the Sidi Boutbal (SB) quarry in the Lower Chelif basin in Algeria. “The Chelif Basin is one of the largest Messinian peripheral sub-basins, characterized by an elongated and ENE–WSW oriented structure spanning over 260 km in length and 35 km in width,” the authors explain in their paper. The quarry contains gypsum deposits that are tens of meters thick.

These figures from the research show gypsum deposits in the Mediterranean, including the Sidi Boutbal quarry in Algeria, where the researchers tested their method. The black stars in C, D, and E show the sampled gypsum unit. Image Credit: Sellam et al. 2025.

The researchers used several methods in their work, including optical microscopy, scanning electron microscopy with energy-dispersive X-ray spectroscopy, and spatially resolved laser ablation mass spectrometry (LIMS). These aren’t new technologies, but combining them into an instrument that can be carried by a rover is new.

In their tests in Algeria, the researchers used a miniature laser-powered mass spectrometer, which can analyze the chemical composition of a sample in detail as fine as a micrometre. They also sampled gypsum and analyzed it using the mass spectrometer and an optical microscope. Many natural rock formations can mimic microbial fossils, so they followed criteria to distinguish between potential microbial fossils and natural rock formations. Microbial fossils display morphology which is irregular, sinuous, and potentially hollow.

In their paper, the authors report finding “a densely interwoven network of brownish, sinuous, and curved fossil filaments of various sizes.”

A is an optical microscope image of permineralized filamentous microfossils, and G is a scanning electron microscope of the same microfossils. Image Credit: Sellam et al. 2025.

Their method also detects the presence of chemical elements necessary for life, carbonaceous material, and minerals like clay or dolomite, which can be influenced by the presence of bacteria. “The inner layer of the filament is morphologically and compositionally distinct from the gypsum, mainly composed of Ca, S, O, and traces of Si,” the authors write.

This is a Scanning Electron Microscope and Energy Dispersive X-ray (SEM-EDX) spectrum of the same area. Red shows the predominant mineral, blue shows clay minerals, and yellow shows the inner layer of the fossil filaments. Image Credit: Sellam et al. 2025.

The authors found not only fossil filaments, but also dolomite, clay minerals, and pyrite surrounding the gypsum they were embedded in. This is important because their presence signals the presence of organic life. Prokaryotes supply elements that clays need to form and also help dolomite form, which often forms in the presence of gypsum. The only way that dolomite can form without life present is under high pressures and temperatures. To scientists’ knowledge, those conditions weren’t present on early Mars.

This is interesting progress, but there’s still lots of work to do.

It starts with identifying clay and dolomite in Martian gypsum. Along with other biosignatures, this indicates that fossilized life is there. If the system can identify other chemical minerals, that would help, too. Ultimately, finding organically formed filaments at the same time would be solid evidence that the planet once supported life.

“While our findings strongly support the biogenicity of the fossil filament in gypsum, distinguishing true biosignatures from abiotic mineral formations remains a challenge,” cautioned Sellam. “An additional independent detection method would improve the confidence in life detection. Additionally, Mars has unique environmental conditions, which could affect biosignature preservation over geological periods. Further studies are needed.”

If this method proves to be reliable, it’ll have to wait a while before being implemented.

The ESA’s Rosalind Franklin rover will launch to Mars in 2028. It will look for subsurface chemical and morphological evidence of life. Its instruments have already been chosen. Other nations and agencies have missions to Mars in the planning and proposal stages, but none of them are full-featured rovers like Curiosity and Perseverance.

However, another rover mission to Mars in the future is almost a certainty. Maybe this technology will be ready to go by then.

“Although the Messinian Salinity Crisis, during which the Primary Lower Gypsum formed, remains only partially understood, future astrobiological investigations on Mars should consider hydrated sulphate deposits as promising indicators of ancient Martian environmental conditions. This contribution underscores that hydrated sulphates serve as archives of biological history on Earth and potentially on Mars, should evidence of past life be found,” the authors conclude.

• Press Release: Laser-powered device tested on Earth could help us detect microbial fossils on Mars
• Published Research: The search for ancient life on Mars using morphological and mass spectrometric analysis: an analog study in detecting microfossils in Messinian gypsum

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The habitable zone of a planetary system is based on a simple idea: if a planet is too close to its star then conditions are too hot for life, and if a planet is too distant then things are too cold. It’s broadly based on the estimated temperature/distance range for liquid water to exist on a planet’s surface, since life as we know it needs liquid water to exist. The problem with this definition is that it’s too crude to be very useful. For example, both Venus and Mars are at the inner and outer edges of the Sun’s habitable zone, but neither are really habitable. But now that we have observed hundreds of planetary systems, we can start to pin down the zone more accurately. One way to do this is to look at sulfur chemistry.

A new paper in Science Advances looks at how sulfur chemistry can better define the inner border of a star’s habitable zone. The authors note that the key is whether a planet can maintain a surface ocean. Many inner planets are warm enough to have liquid oceans early on but lose those oceans over time. Venus is a good example of this. Early Venus was likely very Earth-like, but the lack of a strong magnetic field and water-rich volcanic activity meant Venus’s early oceans boiled away.

Even from light-years away, the difference between Venus and Earth is striking. If alien astronomers were to observe the atmospheres of both, they would see that Earth has a mix of nitrogen and oxygen, while Venus has a mostly carbon dioxide atmosphere rich in sulfur dioxide. From this, they would know that Earth has oceans while Venus does not. Both planets have plenty of sulfur, but Earth’s oceans prevent large amounts of sulfur dioxide from forming. It takes dry surface chemistry to create sulfur dioxide.

The authors show how the presence of atmospheric sulfur is a marker for an oceanless planet. For sunlike stars, this could be used to narrow the habitable zone and select better candidates for alien life. If an inner planet has a sulfur-rich atmosphere, there’s no need to look further. There is, however, a catch.

While dry, warm planets would tend to generate plenty of sulfur compounds, ultraviolet light tends to break these molecules up. So, the team demonstrates, while the presence of atmospheric sulfur proves a planet is dry, the opposite is not always true. A dry planet orbiting a high-UV star would also lack sulfur compounds. To demonstrate this, the team looked at the red dwarf system TRAPPIST-1, which has at least three potentially habitable planets. They found that the UV levels for these worlds are too high to use the sulfur test. This is a real bummer, since red dwarf planets are the most common home for potentially habitable worlds, and most of those planets are bathed in much more UV than Earth since they orbit their star so closely.

So this study shows that sulfur chemistry is a useful tool for finding life, though not as useful as we’d like. It will take more chemical identifiers to narrow down the habitable zones for red dwarfs.

Reference: Jordan, Sean, Oliver Shorttle, and Paul B. Rimmer. “Tracing the inner edge of the habitable zone with sulfur chemistry.” Science Advances 11.5 (2025): eadp8105.

The post Can We Develop a More Accurate Habitable Zone Using Sulfur? appeared first on Universe Today.

Air travel produces around 2.5% of all global CO2 emissions, and despite decades of effort in developing alternative fuels or more efficient aircraft designs, that number hasn’t budged much. However, NASA, also the US’s Aeronautics administration, has kept plugging away at trying to build a more sustainable future for air travel. Recently, they supported another step in that direction by providing an Institute for Advanced Concepts (NIAC) grant to Phillip Ansell of the University of Illinois Urbana-Champaign to develop a hybrid hydrogen-based aircraft engine.

The grant focuses on developing the Hydrogen Hybrid Power for Aviation Sustainable Systems (Hy2PASS) engine, a hybrid engine that uses a fuel cell and a gas turbine to power an aircraft. Hybrid systems have been tried before, but Hy2PASS’s secret sauce is its use of air handling.

In hybrid aircraft systems, there’s typically a fuel cell and a gas turbine. The fuel cell takes hydrogen as an input and creates electrical energy as output. In a typical hybrid system, this electrical energy would power a compressor, whose output was directly coupled to turning the turbine. However, in Hy2PASS, the compressor itself is decoupled from the turbine, though it still supplies oxygen to it. It then also supplies oxygen to the fuel cell’s cathode, allowing for its continued operation.

AI generated video on the Hy2PASS system.

This method has a few advantages, but the most significant one is the dramatic increase in efficiency it allows. The waste heat created at that mechanical connection is eliminated by uncoupling the compressor directly from the turbine. Also, it allows the compressor to be run at different pressures, allowing an algorithm to optimize its speed while ignoring the necessary speed of the turbine.

Additionally, the emissions from the entire system are essentially just water. So, this hybrid system effectively eliminates the emissions created by this kind of hybrid engine altogether. So, in theory, at least, this type of propulsion system would be the holy grail that NASA and the rest of the aviation industry have been seeking for years.

There’s still a long way to go to make this system a reality. The Phase I NIAC grant will focus on proving the system’s concept. Importantly, it will also require an understanding of another aircraft system and “mission trajectory optimization” to minimize the energy requirements of any future use case for the system. That sounds like there would be some limitations for how the system might be used in practice, though fleshing that out as part of Phase I seems a reasonable use case.

Interview with Dr. Ansell, the PI on the Hy2PASS project.

If the project is successful, and given Dr. Ansell’s track record of consistently meeting NASA design objectives, that seems a good bet. It is possible that someday soon, a hydrogen-powered aircraft could be in the air again. And this time, it will be a key player in eliminating emissions from one of the most important industries in the world.

Learn More:
NASA – Hydrogen Hybrid Power for Aviation Sustainable Systems (Hy2PASS)
UT – Multimode Propulsion Could Revolutionize How We Launch Things to Space
UT – Reaction Engines Goes Into Bankruptcy, Taking the Hypersonic SABRE Engine With it
UT – NASA is Working on Electric Airplanes

Lead Image:
Artist’s concept of the Hy2PASS engine
Credit – NASA / Phillip Ansell

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Researchers study enigmatic asteroid Kamo’oalewa, as China’s first asteroid sample return mission moves toward launch.

China is about to get in to the asteroid sample return game. The CNSA (China National Space Administration) has recently announced that its Tianwen-2 mission has arrived at the Xichang Space Center. The mission will launch this May, on a Long March 3B rocket with the agency’s first solar system exploration mission of the year.

The mission was originally named ZhengHe, after a 15th century explorer. Tianwen-2 is a follow-on to China’s Tianwen-1, the nation’s first successful Mars orbiter-lander mission. Set to launch this coming May, Tianwen-2 will perform an ambitious first: not only will it explore asteroid 469219 Kamo’oalewa, but it will head onward to Comet 311P/PanSTARRS, in a first-ever asteroid-comet exploration mission for the agency.

A Tantalizing Worldlet

Certainly, asteroid Kamo’oalewa is an intriguing space rock. An Apollo Group Near Earth Asteroid, Kamo’oalewa is a rare quasi-satellite of the Earth. Discovered on the night of April 27th, 2016 from the Haleakala Observatory, the asteroid received the provisional designation 2016 HO3. The formal name means ‘oscillating fragment’ in the Hawaiian language. The asteroid currently fluctuates from being a quasi-satellite and horseshoe orbit between the Sun-Earth L1-L2 and L4-L5 Lagrange points, respectively. One day—perhaps a 100 million of years or so in the future—Kamo’oalewa may ultimately strike the Earth or the Moon.

A reddish object, Kamo’oalewa is either an S- or L-type asteroid, about 40 to 100-meters in size. The asteroid also bears a striking spectral resemblance to Apollo 14 and Luna 24 soil returns, suggesting it may in fact be ejecta from the impact that formed the Giordano Bruno crater on the Moon. The farside crater is thought to be about 4 million years old.

Giordano Bruno crater on the lunar farside. Credit: NASA/LRO Following Asteroid Kamo’alewa

A recent study out of the European Space Agency’s Near-Earth Objects Coordination Centre (NEOCC) entitled Astrometry, Orbit Determination and Thermal Inertia of the Tianwen-2 Target Asteroid (469219) Kamo’oalewa is looking to better understand the tiny world ahead of the mission’s arrival. Specifically, the study looks to refine the orbit of the asteroid, and understand how the Yarkovsky and YORP (Yarkovsky-O’Keefe-Radzievskii-Paddack) effects act on the orbit and rotation of the asteroid over time. The Yarovsky Effect is the result of how sunlight alters the path of small asteroids over time, as they absorb solar energy and re-emit it as heat. YORP is a similar phenomena, but includes the scattering of sunlight due to the shape and surface structure of the asteroid. Kamo’oalewa is a fast rotator, spinning on its axis once every 27 minutes. This will add to the challenge of grabbing a sample.

“We observed Kamo’oalewa and precisely measured its position in the sky,” lead researcher on the study Marco Fenucci (ESA/ESRIN/NEO Coordination Centre) told Universe Today. “Thanks to these new measurements, we were able to determine the Yarkovsky effect with a signal-to-noise ratio of 14, and the overall accuracy of the orbit was improved.”

Our best view yet of asteroid Kamo’oalewa. Credit: ESA/NEOCC/Loiano Astronomical Station

The study used current observations from the Calar Alto Observatory in Spain and Loiano Astronomical Station based in Italy, as well as pre-discovery observations found in the Sloan Digital Sky Survey (SDSS) from 2004. These were especially challenging for the team to incorporate, as SDSS used a unique drift scan method to complete images. Also, an NEO asteroid like Kamo’oalewa has a relatively fast proper motion against the starry background. These two factors presented a challenge to pinning the asteroid’s time and location down in earlier images.

An Enigmatic World

“Thanks to the accurate measurement of the Yarkovsky effect on Kamo’oalewa, we were able to estimate the surface thermal inertia,” says Fenucci. “Our best estimate indicates that the thermal inertia is smaller than that of Bennu and Ryugu (the target for JAXA’s Hayabusa2 mission). A low value of thermal inertia is usually due to the presence of regolith on the surface of the asteroid. The presence of regolith was not expected on such fast rotators.”

Certainly, the tiny world is worthy of further scrutiny. Any information will be handy leading up the Tianwen-2’s arrival. Like NASA’s OSIRIS-REx, which sampled asteroid 101955 Bennu in 2020, Tianwen-2 will use a touch-and-go sample technique, in addition to an anchor-and-attach method to acquire its samples of asteroid Kamo’oalewa.

“Kamo’oalewa will be the smallest asteroid visited by a spacecraft, and also the one with the shortest rotation period,” says Fenucci. “In terms of composition, the spectrum is similar to that of S-type asteroids, for example, Itokawa or Eros.” The reddish aspect of the asteroid in the visible-to-near infrared part of the spectrum, however, remains a mystery. “This is a typical feature of lunar regolith,” says Fenucci. “However, this particular feature can also be caused by space weathering. The Tianwen-2 mission should give an answer to the question of the origin of Kamo’oalewa.”

Tianwen-2 Mission Timeline

Currently rendezvous with the asteroid is set for 2026, with a departure in 2027. The CNSA team hopes to nab about 100 grams of Kamo’oalewa, about the mass of medium-sized apple. After that, the mission will dispatch its return capsule on Earth flyby in late 2027. Then, it will head onward to explore periodic comet 311/P PanSTARRS. The mission will reach the comet in 2034.

The Tianwen-2 spacecraft to carry out a sample-return targeting near-Earth asteroid 469219 Kamo?oalewa has arrived at Xichang spaceport. Launch date not revealed, but expected around May. english.news.cn/20250220/d95…

[image or embed]

— Andrew Jones (@andrewjonesspace.bsky.social) February 20, 2025 at 6:08 AM

China has certainly taken a prudent, incremental path to space exploration. CNSA’s Chang’e program has returned samples of the lunar near and far side. Tianwen-1 was successful at Mars, scoring a combination orbiter, lander and rover on the Red Planet, all in one mission. China also has long term plans to combine these proven techniques in a Mars sample return mission of their own. This could launch as early as 2028.

It will be exciting to see asteroid Kamo’oalewa up close, as Tianwen-2 attempts to unravel the origin story for this elusive world.

The post China’s Tianwen-2 Is About to Launch. Here’s What We Know About Its Target Kamo’oalewa appeared first on Universe Today.

In 2007, astronomers discovered the Cosmic Horseshoe, a gravitationally lensed system of galaxies about five-and-a-half billion light-years away. The foreground galaxy’s mass magnifies and distorts the image of a distant background galaxy whose light has travelled for billions of years before reaching us. The foreground and background galaxies are in such perfect alignment that they create an Einstein Ring.

New research into the Cosmic Horseshoe reveals the presence of an Ultra-Massive Black Hole (UMBH) in the foreground galaxy with a staggering 36 billion solar masses.

There’s no strict definition of a UMBH, but the term is often used to describe a supermassive black hole (SMBH) with more than 5 billion solar masses. SMBHs weren’t “discovered” in the traditional sense of the word. Rather, over time, their existence became clear. Also, over time, more and more massive ones were measured. There’s a growing need for a name for the most massive ones, and that’s how the term “Ultra-Massive Black Hole” originated.

The discovery of the enormously massive black hole in the Cosmic Horseshoe is presented in new research. It’s titled “Unveiling a 36 Billion Solar Mass Black Hole at the Centre of the Cosmic
Horseshoe Gravitational Lens,” and the lead author is Carlos Melo-Carneiro from the Instituto de Física, Universidade Federal do Rio Grande do Sul in Brazil. The paper is available at arxiv.org.

There was a revolution in physics in the late 19th/early 20th century as relativity superseded Newtonian physics and propelled our understanding of the Universe to the next level. It became clear that space and time were intertwined rather than separate and that massive objects could warp spacetime. Even light wasn’t immune, and Einstein gave the idea of black holes—which dated back to John Michell’s ‘dark stars’—a coherent mathematical foundation. In 1936, Einstein predicted gravitational lensing, though he didn’t live long enough to enjoy the visual proof we enjoy today.

Now, we know of thousands of gravitational lenses, and they’ve become one of astronomers’ naturally occurring tools. They exist because of their enormous black holes.

The lensing foreground galaxy in the Cosmic Horseshoe is named LRG 3-757. It’s a particular type of rare galaxy called a Luminous Red Galaxy (LRG), which are extremely bright in infrared. LRG 3-757 is also extremely massive, about 100 times more massive than the Milky Way and is one of the most massive galaxies ever observed. Now we know that one of the most massive black holes ever detected occupies the center of this enormous galaxy.

“Supermassive black holes (SMBHs) are found at the centre of every massive galaxy, with their masses tightly connected to their host galaxies through a co-evolution over cosmic time,” the authors write in their paper.

Astronomers don’t find stellar-mass black holes at the heart of massive galaxies and they don’t find SMBHs at the heart of dwarf galaxies. There’s an established link between SMBHs and their host galaxies, especially massive ellipticals like LRG 3-757. This study strengthens that link.

The research focuses on what’s called the MBH-sigmae Relation. It’s the relationship between an SMBH’s mass and the velocity dispersion of the stars in the galactic bulge. Velocity dispersion (sigmae) is a measurement of the speed of the stars and how much they vary around the average speed. The higher the velocity dispersion, the faster and more randomly the stars move.

When astronomers examine galaxies, they find that the more massive the SMBH, the greater the velocity dispersion. The relationship suggests a deep link between the evolution of galaxies and the growth of SMBHs. The correlation between an SMBH’s mass and its galaxy’s velocity dispersion is so tight that astronomers can get a good estimate of the SMBH’s mass by measuring the velocity dispersion.

However, the UMBH in the Cosmic Horseshoe is more massive than the MBH-sigma e Relation suggests.

“It is expected that the most massive galaxies in the Universe, such as brightest cluster galaxies (BCGs), host the most massive SMBHs,” the authors write. Astronomers have found many UMBHs in these galaxies, including LRG 3-757. “Nonetheless, the significance of these UMBHs lies in the fact that
many of them deviate from the standard linear MBH?sigmae relation” the researchers explain.

LRG 3-757 deviates significantly from the correlation. “Our findings place the Cosmic Horseshoe ~1.5 sigma above the MBH?sigmae relation, supporting an emerging trend observed in BGCs and other massive galaxies,” the authors write. “This suggests a steeper MBH?sigmae relationship at the highest masses, potentially driven by a different co-evolution of SMBHs and their host galaxies.”

This figure from the research shows the relationship between the SMBH mass and the host effective
velocity dispersion. The black solid line represents the relation from previous research in 2016, with dashed and dotted lines showing the 1 sigma and 3 sigma scatter, respectively. Horseshoe is labelled and clearly deviates from established relationship. The other galaxies labelled nearby also contain UMBHs that deviate significantly. Image Credit: Melo-Carneiro et al. 2025.

What’s behind this decoupling of the MBH?sigmae relation in massive galaxies? Some stars might have been removed from the galaxy in past mergers, affecting the velocity dispersion.

LRG 3-757 could be part of a fossil group, according to the authors. “The lens of the Horseshoe is unique in that is at ? = 0.44 and that has no comparably massive companion galaxies — it is likely a fossil group,” they write.

Fossil groups are large galaxy groups that feature extremely large galaxies in their centers, often LRGs. Fossil groups and LRGs represent a late stage of evolution in galaxies where activity has slowed. Few stars form in LRGs so they’re “red and dead.” There’s also little to no interaction between galaxies.

“Fossil groups, as remnants of early galaxy mergers, may follow distinct evolutionary pathways compared to local galaxies, potentially explaining the high BH mass,” the authors write.

LRG 3-757 could’ve experienced what’s called “scouring.” Scouring can occur when two extremely massive galaxies merge and affects the velocity dispersion of stars in the galaxy’s center. “In this process, the
binary SMBHs dynamically expel stars from the central regions of the merged galaxy, effectively reducing the stellar velocity dispersion while leaving the SMBH mass largely unchanged,” the authors explain.

Another possibility is black hole/AGN feedback. When black holes are actively feeding they’re called Active Galactic Nuclei. Powerful jets and outflows from AGN can quench star formation and possibly alter the central structure of the galaxy. That could decouple the growth of the SMBH from the velocity dispersion.

Artist view of an active supermassive black hole and its powerful jets. Image Credit: ESO/L. Calçada

“A third scenario posits that such UMBH could be remnants of extremely luminous quasars, which experienced rapid SMBH accretion episodes in the early Universe,” the authors write.

The researchers say that more observations and better models are needed “to explain the scatter in the ?BH ? sigma e relation at its upper end.”

More observations are on the way thanks to the Euclid mission. “The Euclid mission is expected to discover hundreds of thousands of lenses over the next five years,” the authors write in their conclusion. The Extremely Large Telescope (ELT) will also contribute by allowing more detailed dynamical studies of the velocity dispersion.

“This new era of discovery promises to deepen our understanding of galaxy evolution and the interplay between baryonic and DM components,” the authors conclude.

The post One of the Most Massive Black Holes in the Universe Lurks at the Center of the Cosmic Horsehoe appeared first on Universe Today.

Venus differs from Earth in many ways including a lack of internal dynamo driving global magnetosphere to shield potential life from solar and cosmic radiation. However, Venus possesses a dense atmosphere and, in a recent study, planetary scientists conducted simulations of the Venusian atmosphere to determine radiation penetration to the lower cloud layers. Their calculations revealed that the atmospheric thickness provides adequate protection for life at what’s considered Venus’s “habitable zone,” located 40–60 km above the surface.

Venus, the second planet from the Sun, is often called Earth’s “sister planet” because of its comparable size and composition. Yet its environment couldn’t be more different or extreme. It has a thick carbon dioxide atmosphere with sulfuric acid clouds that have created a runaway greenhouse effect, making Venus the solar system’s hottest planet—surface temperatures in excess of 475°C. The Venusian landscape features volcanic plains, mountains, and canyons under atmospheric pressure exceeding 90 times Earth’s. Despite these inhospitable conditions, Venus remains an object of scientific interest, with researchers studying its geology and atmosphere.

Venus

In 2020, scientists found phosphine in Venus’s atmosphere which, on Earth, is mostly made by biological processes or in other words – living things. This discovery was somewhat unexpected and facilitated a fresh look at Venus as a possible home for life. Surprisingly perhaps, Venus does have a “habitable zone” in its clouds about 40-60 km up, where the temperature and pressure aren’t too different from Earth’s. While the planet’s surface is totally uninhabitable, high up in the atmosphere might actually support some kind of microbial life that’s adapted to acidic conditions. A new piece of research has been exploring if the thick Venusian atmosphere would protect any such life that may have evolved or whether intense radiation bathes its habitable zone. 

The spectral data from SOFIA overlain atop this image of Venus from NASA’s Mariner 10 spacecraft is what the researchers observed in their study, showing the intensity of light from Venus at different wavelengths. If a significant amount of phosphine were present in Venus’s atmosphere, there would be dips in the graph at the four locations labeled “PH3,” similar to but less pronounced than those seen on the two ends. Credit: Venus: NASA/JPL-Caltech; Spectra: Cordiner et al.

The research, that was led by Luis A. Anchordoqui from the University of New York has revealed surprising results. The team discovered that despite Venus lacking a magnetic field and orbiting closer to the Sun, the radiation levels in its potentially habitable cloud layer are remarkably similar to those at Earth’s surface. Using the AIRES simulation package (AIRshower Extended Simulations – simulates cascades of secondary particles from incoming high energy radiation) the team generated over a billion simulated cosmic ray showers to analyse particle interactions within Venus’s atmosphere. 

Their findings show that at equivalent atmospheric depths, particle fluxes on Venus and Earth are nearly identical, with only about 40% higher radiation detected at the uppermost boundary of Venus’s habitable zone. This suggests Venus’s thick atmosphere provides substantial radiation shielding that might be sufficient for potential microbial life.

The research suggests that cosmic radiation wouldn’t significantly hinder life in Venus’s cloud layer. Any potential microorganisms that were there would face radiation levels similar to those on Earth’s surface. On Earth, life has found a way across a wide range of environments that span many kilometres, this is known as its life reservoir. Venus doesn’t have such a great reservoir so if radiation were to sterilise the habitable clouds, there’s no equivalent to Earth’s subsurface biosphere that could eventually recolonise the region. This means life needs to persist continuously in its atmospheric habitat without being able to move to other parts of the planet.

Source : The Venusian Chronicles

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The journey to Mars will subject astronauts to extended periods of exposure to radiation during their months-long travel through space. While NASA’s Artemis 1 mission lasted only a matter of weeks, it provided valuable radiation exposure data that scientists can use to predict the radiation risks for future Mars crews. The measurements not only validated existing radiation prediction models but also revealed unexpected insights about the effectiveness of radiation shielding strategies too. 

Space radiation poses one of the most significant health risks for astronauts travelling beyond Earth’s magnetic field. Unlike the radiation from medical X-rays or nuclear sources on Earth, space radiation includes high-energy galactic cosmic rays and solar particle events that can penetrate traditional shielding materials. When these particles collide with human tissue, they can damage DNA, increase cancer risk and weaken the immune system. The effects are cumulative too, with longer missions like a journey to Mars significantly increasing exposure and health risks. 

Artist’s illustration of ultra-high energy cosmic rays

The International Space Station crews receive radiation doses similar to nuclear power plant workers due to a little protection from Earth’s magnetosphere, but astronauts traveling to Mars would face much higher exposure levels during their multi-month journey. NASA estimates that a mission to Mars could expose astronauts to radiation levels that exceed current career exposure limits, making effective radiation shielding one of the key challenges for deep space exploration.

A full-disk view of Mars, courtesy of VMC. Credit: ESA

A paper recently published by a team led by Tony C Slaba from the Langley Research Centre at NASA, they use computer models and data from on-board detectors to assess the health risk to long term space flight. The data is taken from the International Space Station (ISS,) the Orion Spacecraft, the BioSentinel CubeSat and from receivers on the surface of Mars. Collectively this data enables a full mission profile to be modelled for a Martian journey. The data was captured during the time period of the Artemis-1 mission, just under one month in duration.

NASA’s Orion spacecraft will carry astronauts further into space than ever before using a module based on Europe’s Automated Transfer Vehicles (ATV). Credit: NASA

Space radiation comes in two primary forms that pose risks to astronauts and spacecraft. Solar Particle Events occur during solar storms, releasing intense bursts of energetic particles from the Sun, while Galactic Cosmic Rays represent a constant stream of highly penetrating radiation from deep space. The findings enabled the team to assess current models for accuracy. They found that predictions match actual measurements to within 10-25% for the International Space Station, 4% for deep space conditions, and 10% for the Martian surface. This level of precision gives confidence in the existing models and in planning radiation protection for future missions.

They also found that, having assessed traditional shielding approaches, that they are largely ineffective against Galactic Cosmic Rays. In some cases, excessive shielding or inappropriate material choices can even amplify radiation exposure through secondary particle production. This occurs when the ‘original radiation’ creates a cascade of new particles on impact that can be more dangerous than the original radiation! They found that radiation levels vary substantially depending on location and the specific shielding configurations used! Quite the headache for engineers!

Radiation exposure is one of the greatest challenges in human space exploration. The study shows that our models for assessing radiation risk are reliable and that the ability to accurately assess those risks is crucial for protecting astronauts from serious health consequences. Having a good understanding of the risk directly influences how spacecraft are engineered, and plays a key role in mission planning for trips beyond Earth orbit. More work is needed now in the design of radiation protection systems if our space travellers are to be better protected from the long term risks posed by radiation.

Source : Validated space radiation exposure predictions from earth to mars during Artemis-I

The post We Know How Much Radiation Astronauts Will Receive, But We Don’t Know How to Prevent it appeared first on Universe Today.

Anthropogenic climate change is creating a vicious circle where rising temperatures are causing glaciers to melt at an increasing rate. In addition to contributing to rising sea levels, coastal flooding, and extreme weather, the loss of polar ice and glaciers is causing Earth’s oceans to absorb more solar radiation. The loss of glaciers is also depleting regional freshwater resources, leading to elevated levels of drought and the risk of famine. According to new findings by an international research effort, there has been an alarming increase in the rate of glacier loss over the last ten years.

The research was conducted by the Glacier Mass Balance Intercomparison Exercise (GlaMBIE) team, a major research initiative coordinated by the World Glacier Monitoring Service (WGMS). Located at the University of Zurich in collaboration with the University of Edinburgh and Earthwave Ltd, this international data repository and data analyzing service generates community estimates of glacier mass loss globally. The paper that details their research and findings, “Community estimate of global glacier mass changes from 2000 to 2023,” was published on February 19th in the journal Nature.

As part of their efforts, the team coordinated the compilation, standardization, and analysis of field measurements and data from optical, radar, laser, and gravimetry satellite missions. These include satellite observations from NASA’s Terra Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Ice, Cloud, and Land Elevation Satellite-2 (ICESat-2), the NASA-DLR Gravity Recovery and Climate Experiment (Grace), the GLR’s TanDEM-X mission, and the ESA’s CryoSat missions, and more.

Combining data from multiple sources, the Glambie team produced an annual time series of global glacier loss from 2000 to 2023. In 2000, glaciers covered about 705,221 square km (272,287 mi2) and held an estimated 121,728 billion metric tons (134,182 US tons) of ice. Over the next twenty years, they lost 273 billion tonnes of ice annually, approximately 5% of their total volume, with regional losses ranging from 2% in the Antarctic and Subantarctic to 39% in Central Europe. To put that in perspective, this amounts to what the entire global population consumes in 30 years.

In short, the amount of ice lost rose to 36% during the second half of the study (2012 and 2023) compared to the first half (2000-2011). Glacier mass loss over the whole study period was 18% higher than the meltwater from the Greenland Ice Sheet and more than double that from the Antarctic Ice Sheet. Michael Zemp, a noted glaciologist who co-led the study, said in an ESA press release:

“We compiled 233 estimates of regional glacier mass change from about 450 data contributors organized in 35 research teams. Benefiting from the different observation methods, Glambie not only provides new insights into regional trends and year-to-year variability, but we could also identify differences among observation methods. This means that we can provide a new observational baseline for future studies on the impact of glacier melt on regional water availability and global sea-level rise.”

This photograph, taken in 2012, shows the Golubin Glacier in Kyrgyzstan, in Central Asia. Credit: M. Hoelzle (2012)

Globally, glaciers collectively lost 6,542 tonnes (7,210 tons) of ice, leading to a global sea-level rise of 18 mm (0.7 inches). However, the rate of glacier ice loss increased significantly from 231 billion tonnes per year in the first half of the study period to 314 billion tonnes per year in the second half – an increase of 36%. This rise in water loss has made glaciers the second-largest contributor to global sea-level rise, surpassing the contributions of the Greenland Ice Sheet, Antarctic Ice Sheet, and changes in land water storage. Said UZH glaciologist Inés Dussaillant, who was involved in the Glambie analyses:

“Glaciers are vital freshwater resources, especially for local communities in Central Asia and the Central Andes, where glaciers dominate runoff during warm and dry seasons. But when it comes to sea-level rise, the Arctic and Antarctic regions, with their much larger glacier areas, are the key players. However, almost Thione-quarter of the glacier contribution to sea-level rise originates from Alaska.”

These results will provide environmental scientists with a refined baseline for interpreting observational differences arising from different methods and for calibrating models. They hope this will help future studies of global ice loss by narrowing the projection uncertainties for the twenty-first century. These research findings are the culmination of many years of cooperative studies and observations, which included the use of satellites that were not specifically designed to monitor glaciers globally. As co-author Noel Gourmelen, a lecturer in Earth Observation of the Cryosphere at the University of Edinburgh, said:

“The research is the result of sustained efforts by the community and by space agencies over many years, to exploit a variety of satellites that were not initially specifically designed for the task of monitoring glaciers globally. This legacy is already producing impact with satellite missions being designed to allow operational monitoring of future glacier evolution, such as Europe’s Copernicus CRISTAL mission which builds on the legacy of ESA’s CryoSat.”

The study also marks an important milestone since it was released in time for the United Nations’ International Year of Glaciers’ Preservation and the Decade of Action for Cryospheric Sciences (2025–2034). Said Livia Jakob, the Chief Scientific Officer & Co-Founder at Earthwave, hosted a large workshop with all the participants to discuss the findings. “Bringing together so many different research teams from across the globe in a joint effort to increase our understanding and certainty of glacier ice loss has been extremely valuable. This initiative has also fostered a stronger sense of collaboration within the community.”

The study also illustrates the importance of collective action on climate change, which is accelerating at an alarming rate. Research that quantifies glacial loss, rising sea levels, and other impacts is key to preparing for the worst. It’s also essential to the development of proper adaptation, mitigation, and restoration strategies consistent with the recommendations made by the UN Intergovernmental Panel on Climate Change (IPCC).

Further Reading: ESA

The post Glaciers Worldwide are Melting Faster Causing Sea Levels to Rise More appeared first on Universe Today.

Satellites often face a disappointing end: despite having fully working systems, they are often de-orbited after their propellant runs out. However, a breakthrough is on the cards with the launch of China’s Shijian-25 satellite which has been launched into orbit to test orbital refuelling operations. The plan; docking with satellite Beidou-3 G7 and transferring 142 kilograms of hydrazine to extend its life by 8 years! It’s success will mean China plans to develop a network of orbital refuelling stations!

Like cars on Earth, satellites need fuel to manoeuvre and for their constantly decaying orbits to be boosted. But unlike vehicles on the ground, when satellites run out of propellant, they become expensive space debris. This challenge has driven the development of orbital refuelling technology, which could extend satellite lifespans and transform space operations.

An artist’s conception of ERS-2 in orbit. ESA

The International Space Station (ISS) offers one of the most well known examples of an orbiting ‘satellite’ and it too needs to deal with boosting its orbit. The problem is the drag imposed upon the structures by gas in our atmosphere. In the case of the ISS, docked supply craft are typically used to fire their engines to reposition ISS to the correct altitude. Without these periodic “orbital boosts,” the ISS would eventually lose altitude and reenter the atmosphere.

The International Space Station (ISS) in orbit. Credit: NASA

A significant milestone in autonomous refuelling came in 2007 with DARPA’s Orbital Express mission. This demonstration involved two spacecraft: the ASTRO servicing vehicle and a prototype modular satellite called NextSat. Over three months, they performed multiple autonomous fuel transfers and component replacements, proving that robotic spacecraft could conduct complex servicing operations without direct human control.

The technology continues to advance with China’s Shijian-25 satellite (launched on 6 January 2025) representing another step forward in orbital refuelling capabilities. The mission aims to demonstrate refuelling operations in geosynchronous orbit approximately 36,000 kilometres above Earth. This is particularly significant because geosynchronous orbits often host communications satellites that benefit from life extension.

The technical challenges of orbital refuelling are considerable though. Spacecraft must achieve extremely precise rendezvous and docking while travelling in excess of 28,000 kilometres per hour. The fuel transfer system must prevent leaks, which could be hazardous to both spacecraft and create hazardous debris. Adding to the challenge is that many satellites were never designed with refuelling in mind, lacking any form of standardised fuel ports or docking interfaces.

Orange balls of light fly across the sky as debris from a SpaceX rocket launched in Texas is spotted over Turks and Caicos Islands on Jan. 16, in this screen grab obtained from social media video. Credit: Marcus Haworth/Reuters

Looking ahead, several companies and space agencies are developing orbital refuelling systems. These range from dedicated “gas station” satellites to more versatile servicing vehicles that can perform repairs and upgrades alongside refuelling. As the technology advances, it could significantly change how we operate in space, making satellite operations more sustainable and cost-effective.

Source : China successfully sent Shijian-25 satellite

The post A Chinese Satellite Tests Orbital Refuelling appeared first on Universe Today.

Astronomers have known for some time that nearby supernovae have had a profound effect on Earth’s evolution. For starters, Earth’s deposits of gold, platinum, and other heavy metals are believed to have been distributed to Earth by ancient supernovae. The blasts of gamma rays released in the process can also significantly affect life, depleting nitrogen and oxygen in the upper atmosphere, depleting the ozone layer, and causing harmful levels of ultraviolet radiation to reach the surface. Given the number of near-Earth supernovae that have occurred since Earth formed 4.5 billion years ago, these events likely affected the evolution of life.

In a new paper by a team of astronomers from the University of California Santa Cruz (UCSC), a nearby supernova may have influenced the evolution of life on Earth. According to their findings, Earth was pummeled by radiation from a nearby supernova about 2.5 million years ago. This burst of radiation was powerful enough to break apart the DNA of living creatures in Lake Tanganyika, the deepest body of water in Africa. This event, they argue, could be linked to an explosion in the number of viruses that occurred in the region.

The study was led by Caitlyn Nojiri, a recent graduate of the USCS Department of Astronomy and Astrophysics. She was joined by Enrico Ramirez-Ruiz, a USCS Professor of astronomy and astrophysics, and Noémie Globus, a postdoctoral fellow at USCS and a member of the Kavli Institute for Particle Astrophysics and Cosmology at Stanford University and the Astrophysical Big Bang Laboratory. The paper that describes their findings appeared on January 15th in the journal Astrophysical Journal Letters.

The image of Lake Tanganyika was acquired in June 1985. Credit: NASA

For their study, the team examined samples of iron-60 retrieved from the seafloor of Lake Tanganyika, the 645 km-long (400 mi) lake in Africa’s Great Rift Valley that borders Burundi, Tanzania, Zambia, and the Democratic Republic of Congo. This radioactive isotope of iron is produced by supernovae and is extremely rare on Earth. They obtained age estimates based on how much the samples had already broken down into nonradioactive forms. This revealed two separate ages for the samples, some 2.5 million years old and the others 6.5 million years old.

The next step was to trace the origin of the iron isotopes, which they did by backtracking the Sun’s motions around the center of the Milky Way. Roughly 6.5 million years ago, our Solar System passed through the Local Bubble, a region of lower density in the interstellar medium (ISM) of the Orion Arm in the Milky Way. As the Solar System entered the Bubble’s stardust-rich exterior, Earth was seeded with the older traces of iron-60. Between 2 and 3 million years ago, a neighboring star went supernova, seeding Earth with the younger traces of iron-60.

To confirm this theory, Nojiri and her colleagues conducted a simulation of a near-Earth supernova, which indicated that it would have bombarded Earth with cosmic rays for 100,000 years after the blast. This model was consistent with a previously recorded spike in radiation that hit Earth around that time. Given the intensity of the radiation, this raised the possibility that it was enough to snap strands of DNA in half. In the meantime, the authors came upon a study of virus diversity in one of Africa’s Rift Valley lakes and saw a possible connection. Said Nojiri in a UCSC news release:

“It’s really cool to find ways in which these super distant things could impact our lives or the planet’s habitability. The iron-60 is a way to trace back when the supernovae were occurring. From two to three million years ago, we think that a supernova happened nearby. We saw from other papers that radiation can damage DNA. That could be an accelerant for evolutionary changes or mutations in cells. We can’t say that they are connected, but they have a similar timeframe. We thought it was interesting that there was an increased diversification in the viruses.”

Lead author Caitlyn Nojiri is now applying for graduate school and hopes to get a Ph.D. in astrophysics. Credit: UCSC

Shortly after their paper was published, Nojiri became the first UCSC undergraduate to be invited to give a seminar at the Center for Cosmology and AstroParticle Physics (CCAPP) at Ohio State. Nojiri did not initially set out to be an astronomer but eventually arrived at UCSC, where Prof. Ramirez-Ruiz encouraged her to apply for the University of California Leadership Excellence through Advanced Degrees (UC LEADS) program. This program is designed to identify undergraduate students from diverse backgrounds who have the potential to succeed in STEM.

She also participated in the Lamat program (“star” in Mayan), which was founded by Ramirez-Ruiz to teach students with great aptitude and nontraditional backgrounds how to conduct research in astronomy. Because of her experience with these programs, Nojiri has decided to apply for graduate school and become an astrophysicist.

“People from different walks of life bring different perspectives to science and can solve problems in very different ways,” said Ramirez-Ruiz. “This is an example of the beauty of having different perspectives in physics and the importance of having those voices.”

Further Reading: UC Santa Cruz, The Astrophysical Journal

The post New Study Proposes that Cosmic Radiation Altered Virus Evolution in Africa appeared first on Universe Today.

How can we explore Saturn’s moon, Enceladus, to include its surface and subsurface ocean, with the goal of potentially discovering life as we know it? This is what a recent study presented at the American Geophysical Union (AGU) 2024 Fall Meeting hopes to address as a team of students and researchers proposed the Thermal Investigation of Geothermal Regions of Enceladus (TIGRE) mission concept, which is designed to conduct in-depth exploration of Enceladus with an orbiter, lander, and drill, while laying the groundwork for future missions to icy moons throughout the solar system.

Here, Universe Today discusses this incredible mission concept with Prabhleen Kour, who is a senior at River Valley High School in Yuba City, CA, and lead author of the study, regarding the motivation behind TIGRE, how TIGRE can improve upon findings from NASA’s now-retired Cassini mission, potential landing sites on Enceladus, how TIGRE can improve missions to other icy moons, the next steps in making TIGRE a reality, and whether she thinks Enceladus has life. Therefore, what was the motivation behind TIGRE?

“TIGRE mission was born during our time with the NASA STEM Enhancement in Earth Science (SEES) program in collaboration with UT Austin’s Center for Space Research,” Kour tells Universe Today. “As part of our internship, our team was tasked to design a space mission within our solar system based on a few assigned parameters. The designed mission had to be aligned to current work being performed by NASA but separate from active missions such as the Europa Clipper. Similarly, the main subject of our mission, Enceladus, and our goals with it, had to be chosen in accordance with the Decadal Survey which dictates what missions and priorities space agencies have. In our case, we were driven to explore a celestial body that might hold the signs of life.”

The TIGRE mission concept comes more than seven years after NASA’s Cassini-Huygen mission ended by performing an intentional dive into Saturn, resulting in Cassini breaking apart in Saturn’s atmosphere. During its storied mission, Cassini spent more than 13 years conducting the most in-depth exploration of Saturn and its many moons, including Titan, Mimas, Atlas, Daphnis, Pandora, Iapetus, Rhea, Dione, Pan, Hyperion, and Enceladus.

Of these moons, Titan and Enceladus are the only two that exhibit potential conditions for life, as Titan is the only moon in the solar system with a dense atmosphere and contains lakes of liquid methane and ethane, while Enceladus boasts a large subsurface ocean that discharge geysers of liquid water from its large crevices in its south pole, dubbed Tiger Stripes. It is the geysers of Enceladus that Cassini not only discovered but flew through twice during its mission, identifying water, carbon dioxide, and a myriad of hydrocarbons and organic materials, the last of which exhibited density 20 times greater than predicted. Therefore, how does TIGRE improve upon findings from the Cassini mission?

Image of Enceladus’ south pole geysers obtained by NASA’s Cassini spacecraft in June 2009. (Credit: NASA/JPL/Space Science Institute)

“Though Cassini’s flyby was incredible and provided us with great information, TIGRE aims to get an incredibly close look at Enceladus’ secrets,” Kour tells Universe Today. “Since TIGRE is designed to go on the surface of Enceladus, it will get more of the ‘inside scoop’ than Cassini. Cassini has already helped us by identifying the organic molecules contained within the ocean, now we want to explore other factors that might make life possible on Enceladus. We are planning to locate any potential regions of interest and stability of habitable zones, analyze samples for organic/inorganic indicators of prebiotic lifeforms, and utilize our findings for future missions. The TIGRE mission contains a drill design, which will reach the subsurface ocean and collect water samples for elements such as CHONPS.”

Enceladus’ Tiger Stripes consist of four main features officially named Damascus Sulcus, Baghdad Sulcus, Cairo Sulcus, and Alexandria Sulcus, with a smaller feature branching off Alexandria called Camphor Sulcus (sulcus being plural for sulci and is an astrogeology term meaning parallel ridges), and are responsible for the geysers that discharge Enceladus’ interior ocean into space. The thickness of the ice in this region is estimated to be approximately 5 kilometers (3.1 miles). Since one of the primary goals of the TIGRE mission is to obtain drill samples of the ocean and identify potential signs of life, the team targeted the Tiger Stripes as potential landing sites for a craft to land and obtain samples of the ocean.

To accomplish this, the team outlined specific landing site criteria to maximize mission success, including landing on relatively flat terrain near a geyser, but not directly on a geyser, to avoid being damaged by uneven terrain or disrupted during geyser activity. Additionally, they determined a low-elevation region would be substantial to minimize the amount of ice the drill would have to penetrate to obtain samples. In the end, the team chose a primary landing site located near the Baghdad stripe that met their landing criteria, located approximately 6.4 kilometers (4 miles) from a geyser and a surface elevation of approximately 450 meters (1,476 feet), along with potential backup landing sites.

Enceladus’ Tiger Stripes. (Credit: NASA/JPL/Space Science Institute)

“Our decision to land near the Baghdad stripe was due to the following: Flat terrain to prevent lander damage, proximity to a geyser, and low elevation to minimize drilling distance,” Kour tells Universe Today. “Any other location that met these requirements were deemed as backups. We analyzed multiple different locations throughout the four stripes, and there were a few that met the requirements on the Cairo stripe. More specifically, one location of interest was between a large geyser and a smaller geyser on the Cario stripe. However, because the location on the Baghdad stripe was close to multiple other smaller geysers, we chose the Baghdad location.”

As noted, Enceladus isn’t the only moon of Saturn that is deemed to potentially have life, as its largest moon, Titan, has a dense and hazy atmosphere caused by specific chemical reactions that scientists have hypothesized existed on early Earth. Additionally, its lakes of liquid methane and ethane have also become prime targets for astrobiologists. Outside of the Saturn system, other icy moons exist throughout the solar system that potentially once had life or could have life today, including Jupiter’s moons, Europa and Ganymede, with both presenting evidence of subsurface oceans circulating beneath their icy crusts.

Venturing closer to the Sun and inside the main asteroid belt orbits the dwarf planet Ceres, which NASA’s Dawn spacecraft identified frozen salts caused by a process known as cryovolcanism. Current models debate the interior structure of Ceres, but it is hypothesized that it once had liquid water long ago. Finally, venturing to the outer portions of the solar system orbits Neptune’s moon, Triton, which NASA’s Voyager 2 spacecraft identified active geysers on its surface comprised of cryolava lakes. Since one of the primary mission objectives of TIGRE is to improve future missions to icy moons, how will it accomplish this?

“The mission will help advance remote sensing, orbiting, landing, and thermal drilling technologies, setting a precedent for future exploration,” Kour tells Universe Today. “TIGRE consists of three main components: the orbiter, lander, and drill. This design is not limited to Enceladus’ surface alone. Instead, this design can be applicable to many other icy surfaces, including those on Earth like Antarctica and other icy moons. Data from the lander’s sampling devices, thermal drill, and the orbiter’s remote sensing will provide comprehensive insights into the composition and formation of Enceladus’s subsurface ocean. These findings could also inform our understanding of other icy moons, broadening our knowledge of potentially habitable environments in the outer Solar System.”

As Universe Today recently discussed with the VATMOS-SR mission concept, it can take anywhere from years to decades for a space mission to go from a concept to reality, involving a myriad of steps and phases, including design, funding rounds, testing, re-designs, re-testing, until it’s finally built and launched. This is followed by several years of traveling to the destination, arriving, and finally collecting science.

For example, the Cassini-Huygens mission was first proposed in 1982 and wasn’t launched until 1997, during which time it endured several years of studies and swapped between a solo NASA mission or a joint NASA-European Space Agency mission, the latter of which was settled upon. After launching in 1997, Cassini finally arrived at Saturn in July 2004, landing the Huygens probe on Titan in January 2005, and spent until 2017 obtaining treasure troves of images and data about Saturn and its many moons, even discovering a few moons along the way and diving through Enceladus’ plumes. Given the journey that Cassini endured, what are the next steps in making TIGRE a reality?

“One of the first steps in making TIGRE a reality is waiting for the completion of the Europa Clipper mission,” Kour tells Universe Today. “In waiting for the mission’s completion, we will be able to see what worked and failed to gather useful samples and what failed to navigate space’s harsh environment. In the meantime, we can advocate for the significance of finding life to enlarge NASA’s budget for active missions. This itself would be a step towards launching the TIGRE mission by opening the resources for improving and testing our mission’s main components (the orbiter, lander, and drill) against the extreme cold, ocean waters, and radiation.”

As noted, Enceladus is a prime target for astrobiologists in the search for life beyond Earth due to its vast subsurface ocean circulating beneath its icy shell. As demonstrated here on Earth, liquid water leads to life as we know it, so Enceladus having a liquid water ocean, even a subsurface ocean, is a strong indicator that it could potentially also have life as we know it, too.

The hydrocarbons discovered by Cassini when the spacecraft flew through Enceladus’ plumes included carbon-bearing molecules like formaldehyde, acetylene, propane, and methane, which is evidence for hydrothermal activity occurring on the ocean floor of Enceladus, much like hydrothermal activity exists on the ocean floors of Earth, specifically regarding the water-rock interactions that occur here, as well. Therefore, in Kour’s opinion, does Enceladus have life and what kinds of life does she foresee finding within their potential TIGRE samples?

“It is not a stretch of reason to state Enceladus could harbor life,” Kour tells Universe Today. “As previously mentioned, Enceladus has the components for life through key elements and has the energy activity to make the possibility of life more plausible. Within the depths of its oceans, Enceladus may very well have life. However, we do not want to explicitly state that there is something there, as there are so many factors at play – thin atmosphere, other chemicals that were potentially not detected by Cassini, and environmental conditions. If there is life and it is similar to the one on Earth, we could expect it to be one of close relations to Archaea. The representatives of this domain are quite primitive and unicellular, which aligns with our hypothesis of Enceladus being able to harbor a simple life form. However, it can also survive harsh conditions – such as extreme cold temperatures on the moon and radiation.”

How will TIGRE help scientists better understand Enceladus and potentially other icy moons throughout the solar system in the coming years and decades? Only time will tell, and this is why we science!

As always, keep doing science & keep looking up!

The post Sampling Enceladus’ Subsurface Ocean with TIGRE Mission Concept appeared first on Universe Today.

Have you ever wondered how astronomers manage to map out the Milky Way when it’s so incredibly vast? One of the most powerful tools is something called 21cm radiation.

Hydrogen, the most abundant element in the universe, plays a key role here. When the electrons in hydrogen atoms flip their spin direction, a specific type of electromagnetic radiation is emitted at a wavelength of 21 centimeters.

The Milky Way galaxy is packed with hydrogen atoms, and these atoms are constantly emitting 21cm radiation. The best part is that this radiation can travel long distances through the interstellar dust that often obscures our view of the galaxy in visible light. This makes 21cm radiation an incredibly useful tool for mapping the structure of the Milky Way.

This radiation reveals everything from star-forming gas clouds to the shapes of the galaxy’s spiral arms. Whereas visible light just gets caught up in all the interstellar dust at it tries to traverse the tens of thousands of light-years across the galaxy, 21cm radiation just sails right though.

But mapping the galaxy’s structure is just one part of the story. Astronomers can also learn about the Milky Way’s rotation by studying the redshift and blueshift of the 21cm radiation. When an object in space moves away from us, the wavelength of the light or radiation it emits gets stretched out, making it appear redder (redshift). Conversely, when an object moves toward us, the wavelength gets compressed, making it appear bluer (blueshift).

By analyzing the redshift and blueshift of the 21cm radiation from different parts of the galaxy, astronomers can determine how fast various regions of the Milky Way are rotating. This information helps them build a more comprehensive picture of our galaxy’s dynamics and motion.

The utility of 21cm radiation isn’t limited to the Milky Way alone. Astronomers can use these same techniques to study distant galaxies as well. By examining the neutral hydrogen gas clouds in far-off galaxies, they can estimate the masses of these galaxies. This is because the amount of 21cm radiation emitted is related to the number of hydrogen atoms present, which in turn gives clues about the galaxy’s overall mass.

21cm radiation is a powerful tool in the field of astronomy that allows astronomers to map the structure of our Milky Way galaxy, understand its rotation, and even estimate the masses of distant galaxies. This technique opens a window into the vast and complex universe, helping us unravel the mysteries of the cosmos with every new observation.

So next time you gaze up at the night sky, remember that there’s a whole lot more going on than meets the eye. Thanks to 21cm radiation, we’re able to peel back the layers of the Milky Way and explore the wonders of the universe in ways that were once unimaginable.

The post How Astronomers Make Deep Maps of the Milky Way appeared first on Universe Today.

NASA astronomers have been continuing to monitor the trajectory of asteroid 2024 YR4. The initial calculations suggested a 1.3% probability of an Earth impact event, which temporarily increased to 3.1% as more data came in. However, and with a sigh of relief, recent analysis brings encouraging news: the Earth impact probability has decreased significantly to 0.28%, though calculations now show a 1% chance of lunar impact. Observations will continue with the James Webb Space Telescope so stay tuned. 

Asteroids are rocky, airless worlds that are remnants left over from the formation of our Solar System about 4.6 billion years ago. They range in size from tiny pebbles to massive bodies hundreds of kilometres across. Most asteroids are found in the asteroid belt between the orbits of Mars and Jupiter although some follow paths that bring them closer to Earth.  Occasionally, they can pose a threat to Earth, which is why astronomers and space agencies closely monitor their orbits and develop potential deflection techniques.

Asteroid Ryugu as seen by Japan’s Hayabusa 2 spacecraft, which returned a sample of the ancient asteroid to Earth in 2020. Image Courtesy ISAS/JAXA

Asteroid 2024 YR4 is one such asteroid that has had gripped the nations media over recent weeks. It’s a near-Earth object that was discovered on 27 December 2024, by the Asteroid Terrestrial-impact Last Alert System (ATLAS) in Chile. Initially, it had an estimated 1.3% chance of impact with Earth in 2032, making it one of the highest-risk asteroids ever recorded. However, further observations raised that risk!

Atlas 2 on Mauna Loa

Astronomers use systems like ATLAS to identify near-Earth objects (NEOs) that could pose a potential threat to our planet. It was developed by the University of Hawaii and funded by NASA and consists of a network of telescopes positioned around the world to provide continuous sky surveys. Its primary goal is to detect asteroids before a potential impact, allowing for timely warnings and mitigation efforts. Since its installation, ATLAS has successfully discovered thousands of asteroids, including hazardous ones just like 2024 YR4. 

Understanding the level of threat from asteroids like 2024 YR4 requires time, time and observations. Imagine a game of tennis and the ball is hit, sending it flying over the net. A photographer sat in the crowd grabs a snapshot of the ball as it flies over the net. The picture is a clear, sharp capture of a point in time however analysis of the image can only reveal the exact location of the ball and not its trajectory. It’s the same with asteroids, once they are discovered, a single observation will reveal where it is but a series of observations are required to understand where it’s going. Ok so this is a simplistic view but it shows how important continued observations are to asteroids like 2024 YR4.

Further observations of asteroid 2024 YR4, conducted during the night of 19-20 February have revealed encouraging results. NASA’s planetary defence team have reported that the probability of an Earth impact has decreased to 0.28%. Monitoring will of course continue to refine trajectory predictions, but current calculations indicate a slight increase in the possibility of lunar impact, now estimated at 1%. These percentages are of course tiny and pose no cause for alarm but 2024 YR4 will continue to be observed over the coming months, just to be sure.

Source : Additional Observations Continue to Reduce Chance of Asteroid Impact in 2032

The post NASA Downgrades the Risk of 2024 YR4 to Below 1% appeared first on Universe Today.

Some exoplanets have characteristics totally alien to our Solar System. Hot Jupiters are one such type. They can have orbital periods of less than 10 days and surface temperatures that can climb to well over 4,000 K (3,730 °C or 6,740 °F). Unlike any planets in our system, they’re usually tidally locked.

Astronomers probed the atmosphere of one hot Jupiter and found some strange winds blowing.

The planet is WASP-121 b, also known as Tylos. It is about 860 light-years away from Earth in the constellation Puppis. It has about 1.16 Jupiter masses and a radius about 1.75 times that of Jupiter. It’s extremely close to its main sequence star and completes an orbit every 1.27 days. Tylos is tidally locked to its star, and its dayside temperature is 3,000 Kelvin (2,730 °C or 4,940 °F), qualifying it as an ultra-hot Jupiter.

“It feels like something out of science fiction.”

Julia Seidel, European Southern Observatory

Since its discovery in 2015, Tylos’ atmosphere has been studied many times. Researchers found water in its stratosphere and hints of titanium oxide and vanadium oxide. They’ve also detected iron and chromium, though some subsequent studies failed to replicate some of these findings.

In new research, scientists examined Tylos’ atmosphere in greater detail with the four telescopes that make up the VLT. With help from the VLT’s ESPRESSO instrument, the researchers found powerful winds blowing through the exoplanet’s atmosphere and confirmed the presence of iron and titanium. The results are in two new papers.

“Even the strongest hurricanes in the Solar System seem calm in comparison.”

Julia Seidel, European Southern Observatory

The first paper, “Vertical structure of an exoplanet’s atmospheric jet stream,” was published in Nature. The lead author is Julia Seidel, a researcher at the European Southern Observatory (ESO).

The second is “Titanium chemistry of WASP-121 b with ESPRESSO in 4-UT mode,” which was published in the journal Astronomy and Astrophysics. The lead author is Bibiana Prinoth, a PhD student at Lund University, Sweden, who is also with the European Southern Observatory.

Some of the researchers involved are co-authors of both papers.

“Ultra-hot Jupiters, an extreme class of planets not found in our solar system, provide a unique window into atmospheric processes,” the authors of the Nature paper write. “The extreme temperature contrasts between their day- and night-sides pose a fundamental climate puzzle: how is energy distributed?”

An artist’s impression of Tylos, also known as WASP-121 b. Image Courtesy: NASA, ESA, Q. Changeat et al., M. Zamani (ESA/Hubble)

“This planet’s atmosphere behaves in ways that challenge our understanding of how weather works — not just on Earth, but on all planets. It feels like something out of science fiction,” said Julia Seidel, the lead author of the study published in Nature.

With the power of the VLT and ESPRESSO, the researchers were able to study Tylos’ atmosphere in detail. No other exoplanet atmosphere has ever been studied in such detail and to such depth. The researchers created a 3D map of the atmosphere, revealing distinct layers and winds.

Tylos’ atmosphere is divided into three layers, with iron winds at the bottom, followed by a very fast jet stream of sodium, and finally, an upper layer of hydrogen winds. This kind of climate has never been seen before on any planet. Image Credit: ESO/M. Kornmesser

“What we found was surprising: a jet stream rotates material around the planet’s equator, while a separate flow at lower levels of the atmosphere moves gas from the hot side to the cooler side. This kind of climate has never been seen before on any planet,” said Seidel. The observed jet stream spans half of the planet, gaining speed and violently churning the atmosphere high up in the sky as it crosses the hot side of Tylos. “Even the strongest hurricanes in the Solar System seem calm in comparison,” she adds.

“It’s truly mind-blowing that we’re able to study details like the chemical makeup and weather patterns of a planet at such a vast distance.”

Bibiana Prinoth, Lund University and the European Southern Observatory

The VLT has an interesting design and is billed by the European Southern Observatory as “the world’s most advanced visible-light astronomical observatory.” It has four main units with 8.2-meter primary mirrors and four smaller, movable auxiliary ‘scopes with 1.8-meter primary mirrors. When working together with the ESPRESSO instrument, the VLT operates as a single, powerful telescope. This combined power meant that the VLT gathered ample data during a single transit of Tylos in front of its star.

“The VLT enabled us to probe three different layers of the exoplanet’s atmosphere in one fell swoop,” said study co-author Leonardo A. dos Santos, an assistant astronomer at the Space Telescope Science Institute. The researchers traced the movement of the winds by tracking the movements of different elements: iron, sodium, and hydrogen correspond to the deep, mid, and shallow layers of the atmosphere. “It’s the kind of observation that is very challenging to do with space telescopes, highlighting the importance of ground-based observations of exoplanets,” he adds.

This diagram shows the structure and motion of the atmosphere of the exoplanet Tylos (WASP-121b). The exoplanet is shown from above in this figure, looking at one of its poles. The planet rotates counter-clockwise in such a way that it always shows the same side to its parent star. One side is perpetual day, and the other is perpetual night. The transition between night and day is the “morning side,” while the “evening side” represents the transition between day and night; its morning side is to the right, and its evening side is to the left. Image Credit: ESO/M. Kornmesser

The observations revealed an exoplanet atmosphere with unusual complexity.

When Tylos crosses in front of its host star, known as a transit, atoms in the planet’s atmosphere absorb specific wavelengths of starlight, which was measured with the VLT’s ESPRESSO instrument. With that data, astronomers reconstructed the composition and velocity of different layers in the atmosphere. An iron wind blows in the deepest layer, away from the point of the planet where the star is directly overhead. Above the iron layer is a very fast jet of sodium that moves faster than the planet rotates. The sodium jet accelerates as it moves from the planet’s morning side to its evening side. The upper layer is made of hydrogen, where the wind blows outwards. The hydrogen layer overlaps with the sodium jet below it.

The authors explain that this unusual planet is more than just an oddity. Its unusual characteristics make it a great testbed for Global Circulation Models. “By resolving the vertical structure of atmospheric dynamics, we move beyond integrated global snapshots of the atmosphere, enabling more accurate identification of flow patterns and allowing for a more nuanced comparison to models,” the authors explain.

The study published in Astronomy and Astrophysics is also based on data from the VLT and ESPRESSO. It uncovered more details of Tylos’ atmosphere, including its chemistry. “The transmission spectrum of WASP-121 b has been extensively studied using the cross-correlation technique, resulting in detections and confirmations for various atoms and ions, including H I, Mg I, Ca I, V I, Cr I, Fe I, Ni I, Fe II, Ca II, and K I, Ba II,” the authors write. “We confirm all these detections and additionally report detections for Ti I, Mn I, Co I Sr I, and Sr II.”

“This experience makes me feel like we’re on the verge of uncovering incredible things we can only dream about now.”

Bibiana Prinoth, Lund University and the European Southern Observatory

The researchers found titanium just below the jet stream. This finding is interesting because previous research detected titanium and subsequent research refuted that. “We attribute the capability of detecting Ti I to the superior photon-collecting power enabled by using ESPRESSO in 4-UT mode compared to a single 1-UT transit and to improvements in the application of the cross-correlation technique,” the authors explain.

The cross-correlation technique is a powerful method for studying exoplanet atmospheres. Light from the atmosphere is much fainter than light from the star and can be obscured by the much stronger starlight. The cross-correlation technique helps overcome this by comparing the observed spectrum with the known “template” spectrum of specific molecules and atoms expected to be present in the atmosphere.

This figure shows the two-dimensional cross-correlation function of H I, Li I, Na I, Mg I, K I, Ca I, Ti I, V I, Cr I, Mn I, Fe I, Fe II, Co I, Ni I, Ba II, Sr I and Sr II. The last panel shows the cross-correlation function for the entire atmospheric model. Image Credit: Prinoth et al. 2025.

“It’s truly mind-blowing that we’re able to study details like the chemical makeup and weather patterns of a planet at such a vast distance,” said Bibiana Prinoth, lead author of the Astronomy and Astrophysics paper.

“The 4-UT mode of ESPRESSO, with its effective photon collecting area equivalent to that of a 16-meter class telescope, serves as a valuable test-bed for pushing the limits of S/N on relatively faint targets,” the authors write in their conclusion.

The study of exoplanet atmosphere with ground-based telescopes will soon get a big boost. In 2028, the long-awaited Extremely Large Telescope should begin operations. It will have a 39.3-metre-diameter primary mirror, giving it 250 times more light-gathering area than the Hubble. It will also feature powerful instruments to probe exoplanet atmospheres.

“The present analysis also allows us to anticipate the observational capabilities of the soon-to-be-commissioned ELT, particularly with regard to time-resolved studies of exoplanet atmospheres,” the authors write.

Who knows what further strangeness is waiting to be discovered in exoplanet atmospheres?

“The ELT will be a game-changer for studying exoplanet atmospheres,” said Prinoth. “This experience makes me feel like we’re on the verge of uncovering incredible things we can only dream about now.”

• Press Release: First 3D observations of an exoplanet’s atmosphere
• Research: Vertical structure of an exoplanet’s atmospheric jet stream
• Research: Titanium chemistry of WASP-121 b with ESPRESSO in 4-UT mode

The post Strange Winds Blow Through this Exoplanet’s Atmosphere appeared first on Universe Today.

Stars form in Giant Molecular Clouds (GMCs), vast clouds of mostly hydrogen that can span tens of light years. These stellar nurseries can form thousands of stars. Astronomers know this because they observe these regions in the Milky Way and the Magellanic Clouds and watch as stars take shape.

But the Universe is more than 13 billion years old and has been forming stars for almost that entire time. The early Universe was different in notable ways. Was star formation any different in the early Universe?

One of the main differences between the early Universe and the modern Universe is metallicity. Elements heavier than hydrogen and helium, called metals in astronomy, didn’t exist in the very early Universe. Only after massive stars formed and died did the Universe’s metallicity increase. Metallicity affects many different processes, including star formation. Metals help cool down clouds of gas and dust, allowing them to collapse and form stars.

Scientists know a lot about the star formation process, but there are many outstanding questions. One of them concerns star formation in the early, low-metallicity Universe. How different was the star formation process billions of years ago?

“We can’t go back in time to study star formation in the early universe, but we can observe parts of the universe with environments similar to the early universe.”

Kazuki Tokuda, Kyushu University, Japan

New research in The Astrophysical Journal tackled the question. It’s titled “ALMA 0.1 pc View of Molecular Clouds Associated with High-mass Protostellar Systems in the Small Magellanic Cloud: Are Low-metallicity Clouds Filamentary or Not?” The lead author is Kazuki Tokuda, a Post-doctoral fellow in the Department of Earth and Planetary Sciences in the Faculty of Science at Kyushu University in Japan. Tokuda is also affiliated with the National Astronomical Observatory of Japan.

This simulation shows stars forming in a molecular cloud, including the jets emitted by young protostars. Astrophysicists know a lot about the star-formation process, but there are still many questions awaiting comprehensive answers. Video Credit: Mike Grudic/STARFORGE

“Even today our understanding of star formation is still developing, comprehending how stars formed in the earlier universe is even more challenging,” said lead author Tokuda in a press release. “The early universe was quite different from today, mostly populated by hydrogen and helium. Heavier elements formed later in high-mass stars. We can’t go back in time to study star formation in the early universe, but we can observe parts of the universe with environments similar to the early universe.”

One of those places is the Small Magellanic Cloud (SMC), a dwarf galaxy near the Milky Way. The SMC’s metallicity is much lower than the Milky Way’s, containing only about one-fifth as many metals. This makes it analogous to the early Universe about 10 billion years ago.

In the Milky Way, star-forming molecular clouds tend to have a filamentary structure. Astronomers have wondered whether these same filamentary shapes are a universal feature found throughout cosmic time. “To test whether these structures are universal throughout cosmic star formation history, it is crucial to study low-metallicity environments within the Local Group,” the authors explain in their paper. Since the SMC is a close neighbour and also has a low metallicity, it’s a good place to look. However, searching the SMC for these filamentary features has been difficult due to the insufficient spatial resolution of many observatories.

The researchers used the Atacama Large Millimeter-submillimeter Array’s (ALMA) power to examine the SMC and see if it has the same star-forming filamentary structures. They focused on the molecular clouds associated with massive young stellar objects (YSOs) in the (SMC).

This image from the research shows the overall view of the SMC and the positions of the target YSOs. Image Credit: Tokuda et al. 2025.

“In total, we collected and analyzed data from 17 molecular clouds. Each of these molecular clouds had growing baby stars 20 times the mass of our Sun,” said lead author Tokuda in a press release. “We found that about 60% of the molecular clouds we observed had a filamentary structure with a width of about 0.3 light-years, but the remaining 40% had a ‘fluffy’ shape. Furthermore, the temperature inside the filamentary molecular clouds was higher than that of the fluffy molecular clouds.”

This figure from the new research shows the 17 molecular clouds the researchers observed with ALMA. Most had the same filamentary shape as clouds in the Milky Way, shown in the yellow boxes. But 40% had a fluffy shape, as shown in the blue boxes. Image Credit: (ALMA (ESO/NAOJ/NRAO), Tokuda et al. 2025, ESA/Herschel)

In their paper, the authors describe it this way: “Our analysis shows that about 60% of the clouds have steep radial profiles from the spine of the elongated structures, while the remaining clouds have a smooth distribution and are characterized by lower brightness temperatures. We categorize the former as filaments and the latter as nonfilaments.”

This figure shows the 17 molecular clouds in the study. The ones with yellow check marks are the ones identified as filaments. Image Credit: Tokuda et al. 2025.

The clouds were not uniform and displayed a diversity of shapes. The researchers classified them into four separate types: single filaments, hub filaments, spatially compact clouds, and diffuse clouds.

These panels illustrate the four types of filaments the authors used to categorize their observations: (a) single filaments, (b) hub filaments, (c) spatially compact clouds, and (d) diffuse clouds. Image Credit: Tokuda et al. 2025.

The temperature difference between the filamentary and fluffy shapes was probably due to their ages. The authors think all clouds started out as filamentary and had high temperatures due to cloud-to-cloud collisions. The clouds have weak turbulence when the temperatures are higher.

However, as the temperature drops, the movement of the incoming gas creates more turbulence. This smooths out the filamentary structure, creating the fluffy shapes.

According to the research, filamentary and fluffy clouds form stars differently. Clouds that hold onto their filamentary shapes are more likely to break apart along their length and form many lower-mass stars similar to our Sun, including planetary systems. When the filamentary structure changes to a fluffy structure, it becomes more difficult for such stars to form.

The implication is that the morphology of the clouds tells us about their evolutionary stages.

“Some of the filamentary clouds are associated with YSOs with outflows and exhibit higher temperatures, likely reflecting their formation conditions, suggesting that these clouds are younger than the nonfilamentary ones,” the authors write in their paper.

The study also emphasizes that the same temperature and structure changes have not been observed in higher metallicity environments like the Milky Way. “Such transitions in structure and temperature have not been reported in metal-rich regions, highlighting a key behaviour for characterizing the evolution of the interstellar medium and star formation in low-metallicity environments,” the authors explain.

With these results, Tokuda says the next step will be to compare them with observations of the Milky Way and other environments richer in heavy elements.

“This study indicates that the environment, such as an adequate supply of heavy elements, is crucial for maintaining a filamentary structure and may play an important role in the formation of planetary systems,” said Tokuda. “In the future, it will be important to compare our results with observations of molecular clouds in heavy-element-rich environments, including the Milky Way galaxy. Such studies should provide new insights into the formation and temporal evolution of molecular clouds and the universe.”

There are still more details to uncover about these filaments, what shapes them, and how they affect the stars they form. How does turbulence play its role? What role do magnetic fields play? Some filaments host YSOs with protostellar outflows. How does that radiative feedback affect the filaments?

Future research will address those questions.

“Future studies using the James Webb Space Telescope to measure the detailed IMF <initial mass function> down to the low-mass regime, combined with ALMA’s ability to probe the physical properties of the parent molecular gas, will be crucial to deepening our understanding of star formation in low-metallicity environments,” the authors conclude.

• Press Release: In ancient stellar nurseries, some stars are born of fluffy clouds
• Research: ALMA 0.1 pc View of Molecular Clouds Associated with High-mass Protostellar Systems in the Small Magellanic Cloud: Are Low-metallicity Clouds Filamentary or Not?

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