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.
Investor's Corner
Tesla gets bold Robotaxi prediction from Wall Street firm
Last week, Andrew Percoco took over Tesla analysis for Morgan Stanley from Adam Jonas, who covered the stock for years. Percoco seems to be less optimistic and bullish on Tesla shares, while still being fair and balanced in his analysis.
Tesla (NASDAQ: TSLA) received a bold Robotaxi prediction from Morgan Stanley, which anticipates a dramatic increase in the size of the company’s autonomous ride-hailing suite in the coming years.
Last week, Andrew Percoco took over Tesla analysis for Morgan Stanley from Adam Jonas, who covered the stock for years. Percoco seems to be less optimistic and bullish on Tesla shares, while still being fair and balanced in his analysis.
Percoco dug into the Robotaxi fleet and its expansion in the coming years in his latest note, released on Tuesday. The firm expects Tesla to increase the Robotaxi fleet size to 1,000 vehicles in 2026. However, that’s small-scale compared to what they expect from Tesla in a decade.
Tesla expands Robotaxi app access once again, this time on a global scale
By 2035, Morgan Stanley believes there will be one million Robotaxis on the road across multiple cities, a major jump and a considerable fleet size. We assume this means the fleet of vehicles Tesla will operate internally, and not including passenger-owned vehicles that could be added through software updates.
He also listed three specific catalysts that investors should pay attention to, as these will represent the company being on track to achieve its Robotaxi dreams:
- Opening Robotaxi to the public without a Safety Monitor. Timing is unclear, but it appears that Tesla is getting closer by the day.
- Improvement in safety metrics without the Safety Monitor. Tesla’s ability to improve its safety metrics as it scales miles driven without the Safety Monitor is imperative as it looks to scale in new states and cities in 2026.
- Cybercab start of production, targeted for April 2026. Tesla’s Cybercab is a purpose-built vehicle (no steering wheel or pedals, only two seats) that is expected to be produced through its state-of-the-art unboxed manufacturing process, offering further cost reductions and thus accelerating adoption over time.
Robotaxi stands to be one of Tesla’s most significant revenue contributors, especially as the company plans to continue expanding its ride-hailing service across the world in the coming years.
Its current deployment strategy is controlled and conservative to avoid any drastic and potentially program-ruining incidents.
So far, the program, which is active in Austin and the California Bay Area, has been widely successful.
News
Tesla Model Y L is gaining momentum in China’s premium segment
This suggests that the addition of the Model Y L to Tesla China’s lineup will not result in a case of cannibalization, but a possible case of “premiumization” instead.
Tesla’s domestic sales in China held steady in November with around 73,000 units delivered, but a closer look at the Model Y L’s numbers hints at an emerging shift towards pricier variants that could very well be boosting average selling prices and margins.
This suggests that the addition of the Model Y L to Tesla China’s lineup will not result in a case of cannibalization, but a possible case of “premiumization” instead.
Tesla China’s November domestic numbers
Data from the a Passenger Car Association (CPCA) indicated that Tesla China saw domestic deliveries of about 73,000 vehicles in November 2025. This number included 34,000 standard Model Y units, 26,000 Model 3 units, and 13,000 Model Y L units, as per industry watchers.
This means that the Model Y L accounted for roughly 27% of Tesla China’s total Model Y sales, despite the variant carrying a ~28% premium over the base RWD Model Y that is estimated to have dominated last year’s mix.
As per industry watcher @TSLAFanMtl, this suggests that Tesla China’s sales have moved towards more premium variants this year. Thus, direct year-over-year sales comparisons might miss the bigger picture. This is true even for the regular Model Y, as another premium trim, the Long Range RWD variant, was also added to the lineup this 2025.
November 2025 momentum
While Tesla China’s overall sales this year have seen challenges, the Model Y and Model 3 have remained strong sellers in the country. This is especially impressive as the Model Y and Model 3 are premium-priced vehicles, and they compete in the world’s most competitive electric vehicle market. Tesla China is also yet to roll out the latest capabilities of FSD in China, which means that its vehicles in the country could not tap into their latest capabilities yet.
Aggregated results from November suggest that the Tesla Model Y took the crown as China’s #1 best-selling SUV during the month, with roughly 34,000 deliveries. With the Model Y L, this number is even higher. The Tesla Model 3 also had a stellar month, seeing 25,700 deliveries during November 2025.
Cybertruck
Tesla Cybertruck earns IIHS Top Safety Pick+ award
To commemorate the accolade, the official Cybertruck account celebrated the milestone on X.
The Tesla Cybertruck has achieved the Insurance Institute for Highway Safety’s (IIHS) highest honor, earning a Top Safety Pick+ rating for 2025 models built after April 2025.
The full-size electric pickup truck’s safety rating is partly due to the vehicle’s strong performance in updated crash tests, superior front crash prevention, and effective headlights, among other factors. To commemorate the accolade, the official Cybertruck account celebrated the milestone on X.
Cybertruck’s IIHS rating
As per the IIHS, beginning with 2025 Cybertruck models built after April 2025, changes were made to the front underbody structure and footwell to improve occupant safety in driver-side and passenger-side small overlap front crashes. The moderate overlap front test earned a good rating, and the updated side impact test also received stellar marks.
The Cybertruck’s front crash prevention earned a good rating in pedestrian scenarios, with the standard Collision Avoidance Assist avoiding collisions in day and night tests across child, adult crossing, and parallel paths. Headlights with high-beam assist compensated for limitations, contributing to the top award.
Safest and most autonomous pickup
The Cybertruck is one of only two full-size pickups to receive the IIHS’ Top Safety Pick + rating. It is also the only one equipped with advanced self-driving features via Tesla’s Full Self-Driving (Supervised) system. Thanks to FSD, the Cybertruck can navigate inner city streets and highways on its own with minimal supervision, adding a layer of safety beyond passive crash protection.
Community reactions poured in, with users praising the vehicle’s safety rating amidst skepticism from critics. Tesla itself highlighted this by starting its X post with a short clip of a Cybertruck critic who predicted that the vehicle will likely not pass safety tests. The only question now is, of course, if the vehicle’s Top Safety Pick+ rating from the IIHS will help the Cybertruck improve its sales.