Mars is a dry, desert world devoid of any life (that we know of). But once upon a time, that wasn’t the case. Data collected by the robotic emissaries we’ve sent to explore the planet on our behalf indicate that the red planet was once a lush and wet world.
However, scientists are still trying to piece together Martian history to understand what happened to the planet’s water. While we know much of it was lost when the planet’s atmosphere was stripped away, what we don’t know is where the water originated from. Researchers uncovered a crucial clue in Martian meteorites found here on Earth.
“A lot of people have been trying to figure out Mars’ water history,” Jessica Barnes, an assistant professor of planetary sciences in the University of Arizona Lunar and Planetary Laboratory, said in a statement. “Like, where did water come from? How long was it in the crust (surface) of Mars? Where did Mars’ interior water come from? What can water tell us about how Mars formed and evolved?”
Like the Earth, Mars is made of different layers: a crust, mantle, and a core. Meteorites, like the ones that fell to Earth, are made of the Martian crust, which can tell us a lot about the planet’s composition when the pieces are analyzed. According to a study published this week in Nature Geoscience, there could be at least two distinct reservoirs of ancient water lurking below the Martian surface. Each with its own (different) chemical signature.
This means that Mars probably never had a global ocean of magma beneath its surface like we do on Earth.
For this study, Barnes and her team looked for clues as to the Mars’ water history by analyzing the ratio of two types (isotopes) of hydrogen. They’re not the first to do so, but previous results have been very inconsistent.
To better understand how the planet formed and where its water came from, the researchers examined two different meteorites: a coin-sized sample known as Black Beauty (or NWA 7034), which formed when a huge impact cemented together various pieces of the Martian crust, and Allan Hills 84001 (ALH84001), a sample once thought to contain Martian microbes. The data shows that water comes from two different sources.
The team was searching for different isotopes of hydrogen — light hydrogen and heavy hydrogen — which can help trace the origin of water in rocks. (Isotopes are variations of chemical elements, with different numbers of neutrons.)
“Light hydrogen” contains one proton (and no neutrons) in its nucleus, whereas “heavy hydrogen,” also known as deuterium, contains one proton and one neutron in its core. The ratio of these two isotopes act like a fossil record of water, telling a planetary scientist its origin.
Here on Earth, protium (or light hydrogen) is the most abundant isotope. It’s found in the atmosphere, in rocks, and the ocean. On Mars, however, deuterium (heavy hydrogen) is the most abundant in the atmosphere, while Martian rocks contain a range of ratios from Earth-like to Mars-like.
To better understand the vast variation, Barnes and her team decided to focus on samples they knew came from the Martian crust — Black Beauty and Alan Hills. The team found that both samples interacted with water at different point in Mars’ history, but had similar isotope ratios, that was very similar to younger rocks analyzed by the Curiosity rover.
This data suggested a surprising result: that the chemical composition of that water hasn’t changed for nearly 4 billion years.
“Martian meteorites basically plot all over the place, and so trying to figure out what these samples are telling us about water in the mantle of Mars has historically been a challenge,” Barnes said.”The fact that our data for the crust was so different prompted us to go back through the scientific literature and scrutinize the data.”
So the team compared their results to previous isotope studies, where the meteorites originated in the Martian mantle. They discovered that the isotope ratios were consistent with two types of volcanic rock, known as shergottite, that’s found in the Martian mantle.
This means that the water within the meteorite samples came from two different sources. It also indicates that Mars lacked a global magma ocean, which would have made the mantle more consistent in its composition.
“These two different sources of water in Mars’ interior might be telling us something about the kinds of objects that were available to coalesce into the inner, rocky planets,” Barnes said.
Meaning two distinct planetary precursors with vastly different water contents could have collided, but never thoroughly mixed. And understanding how Mars formed is essential for understanding its past habitability and potential for life.
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Elon Musk’s Grokipedia surges to 5.6M articles, almost 79% of English Wikipedia
The explosive growth marks a major milestone for the AI-powered online encyclopedia, which was launched by Elon Musk’s xAI just months ago.
Elon Musk’s Grokipedia has grown to an impressive 5,615,201 articles as of today, closing in on 79% of the English Wikipedia’s current total of 7,119,376 articles.
The explosive growth marks a major milestone for the AI-powered online encyclopedia, which was launched by Elon Musk’s xAI just months ago. Needless to say, it would only be a matter of time before Grokipedia exceeds English Wikipedia in sheer volume.
Grokipedia’s rapid growth
xAI’s vision for Grokipedia emphasizes neutrality, while Grok’s reasoning capabilities allow for fast drafting and fact-checking. When Elon Musk announced the initiative in late September 2025, he noted that Grokipedia would be an improvement to Wikipedia because it would be designed to avoid bias.
At the time, Musk noted that Grokipedia “is a necessary step towards the xAI goal of understanding the Universe.”
Grokipedia was launched in late October, and while xAI was careful to list it only as Version 0.1 at the time, the online encyclopedia immediately earned praise. Wikipedia co-founder Larry Sanger highlighted the project’s innovative approach, noting how it leverages AI to fill knowledge gaps and enable rapid updates. Netizens also observed how Grokipedia tends to present articles in a more objective manner compared to Wikipedia, which is edited by humans.
Elon Musk’s ambitious plans
With 5,615,201 total articles, Grokipedia has now grown to almost 79% of English Wikipedia’s article base. This is incredibly quick, though Grokipedia remains text-only for now. xAI, for its part, has now updated the online encyclopedia’s iteration to v0.2.
Elon Musk has shared bold ideas for Grokipedia, including sending a record of the entire knowledge base to space as part of xAI’s mission to preserve and expand human understanding. At some point, Musk stated that Grokipedia will be renamed to Encyclopedia Galactica, and it will be sent to the cosmos.
“When Grokipedia is good enough (long way to go), we will change the name to Encyclopedia Galactica. It will be an open source distillation of all knowledge, including audio, images and video. Join xAI to help build the sci-fi version of the Library of Alexandria!” Musk wrote, adding in a later post that “Copies will be etched in stone and sent to the Moon, Mars and beyond. This time, it will not be lost.”
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Tesla Model 3 becomes Netherlands’ best-selling used EV in 2025
More than one in ten second-hand electric cars sold in the country last year was a Tesla Model 3.
The Tesla Model 3 became the most popular used electric car in the Netherlands in 2025, cementing its dominance well beyond the country’s new-car market.
After years at the top of Dutch EV sales charts, the Model 3 now leads the country’s second-hand EV market by a wide margin, as record used-car purchases pushed electric vehicles further into the mainstream.
Model 3 takes a commanding lead
The Netherlands recorded more than 2.1 million used car sales last year, the highest level on record. Of those, roughly 4.8%, or about 102,000 vehicles, were electric. Within that growing segment, the Tesla Model 3 stood far ahead of its competitors.
In 2025 alone, 11,338 used Model 3s changed hands, giving the car an 11.1% share of the country’s entire used EV market. That means more than one in ten second-hand electric cars sold in the country last year was a Tesla Model 3, Auto Week Netherlands reported. The scale of its lead is striking: the gap between the Model 3 and the second-place finisher, the Volkswagen ID3, is more than 6,700 vehicles.
Rivals trail as residual values shape rankings
The Volkswagen ID.3 ranked a distant second, with 4,595 used units sold and a 4.5% market share. Close behind was the Audi e-tron, which placed third with 4,236 registrations. As noted by Auto Week Netherlands, relatively low residual values likely boosted the e-tron’s appeal in the used market, despite its higher original price.
Other strong performers included the Kia Niro, the Tesla Model Y, and the Hyundai Kona, highlighting continued demand for compact and midsize electric vehicles with proven range and reliability. No other model, however, came close to matching the Model 3’s scale or market presence.
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Tesla Model Y Standard Long Range RWD launches in Europe
The update was announced by Tesla Europe & Middle East in a post on its official social media account on X.
Tesla has expanded the Model Y lineup in Europe with the introduction of the Standard Long Range RWD variant, which offers an impressive 657 km of WLTP range.
The update was announced by Tesla Europe & Middle East in a post on its official social media account on X.
Model Y Standard Long Range RWD Details
Tesla Europe & Middle East highlighted some of the Model Y Standard Long Range RWD’s most notable specs, from its 657 km of WLTP range to its 2,118 liters of cargo volume. More importantly, Tesla also noted that the newly released variant only consumes 12.7 kWh per 100 km, making it the most efficient Model Y to date.
The Model Y Standard provides a lower entry point for consumers who wish to enter the Tesla ecosystem at the lowest possible price. While the Model 3 Standard is still more affordable, some consumers might prefer the Model Y Standard due to its larger size and crossover form factor. The fact that the Model Y Standard is equipped with Tesla’s AI4 computer also makes it ready for FSD’s eventual rollout to the region.
Top Gear’s Model Y Standard review
Top Gear‘s recent review of the Tesla Model Y Standard highlighted some of the vehicle’s most notable features, such as its impressive real-world range, stellar infotainment system, and spacious interior. As per the publication, the Model Y Standard still retains a lot of what makes Tesla’s vehicles well-rounded, even if it’s been equipped with a simplified interior.
Top Gear compared the Model Y Standard to its rivals in the same segment. “The introduction of the Standard trim brings the Model Y in line with the entry price of most of its closest competition. In fact, it’s actually cheaper than a Peugeot e-3008 and costs £5k less than an entry-level Audi Q4 e-tron. It also makes the Ford Mustang Mach-E look a little short with its higher entry price and worse range,” the publication wrote.
Elon Musk’s Grokipedia surges to 5.6M articles, almost 79% of English Wikipedia
Tesla Model 3 becomes Netherlands’ best-selling used EV in 2025
