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.
Tesla Semi Program Director Dan Priestly teased the major improvements to the all-electric Class 8 truck on Thursday night, following the company’s decision to overhaul the design earlier this year.
Priestley said he drove the Semi on Thursday, and the improvements appear to be welcomed by one of the minds behind the project. “Our customers are going to love it,” he concluded.
Just drove the redesigned Semi. Our customers are going to love it. https://t.co/KZ88sf1CDL
— Dan Priestley (@danWpriestley) December 19, 2025
The small detail does not seem like much, but it is coming from someone who has been involved in the development of the truck from A to Z. Priestley has been involved in the Semi program since November 2015 and has slowly worked his way through the ranks, and currently stands as the Director of the program.
Tesla Semi undergoes major redesign as dedicated factory preps for deliveries
Tesla made some major changes to the Semi design as it announced at the 2025 Annual Shareholder Meeting that it changed the look and design to welcome improvements in efficiency.
Initially, Tesla adopted the blade-like light bar for the Semi, similar to the one that is present on the Model Y Premium and the Cybertruck.
Additionally, there are some slight aesthetic changes to help with efficiency, including a redesigned bumper with improved aero channels, a smaller wraparound windshield, and a smoother roofline for better aero performance.
All of these changes came as the company’s Semi Factory, which is located on Gigafactory Nevada’s property, was finishing up construction in preparation for initial production phases, as Tesla is planning to ramp up manufacturing next year. CEO Elon Musk has said the Semi has attracted “ridiculous demand.”
The Semi has already gathered many large companies that have signed up to buy units, including Frito-Lay and PepsiCo., which have been helping Tesla test the vehicle in a pilot program to test range, efficiency, and other important metrics that will be a major selling point.
Tesla will be the Semi’s first user, though, and the truck will help solve some of the company’s logistics needs in the coming years.
Tesla is dominating in the United Kingdom so far through 2025, and with about two weeks left in the year, the Model Y and Model 3 are leading the way.
The Model Y and Model 3 are the two best-selling electric vehicles in the United Kingdom, which is comprised of England, Scotland, Wales, and Northern Ireland, and it’s not particularly close.
According to data gathered by EU-EVs, the Model Y is sitting at 18,890 units for the year, while the Model 3 is slightly behind with 16,361 sales for the year so far.
The next best-selling EV is the Audi Q4 e-tron at 10,287 units, lagging significantly behind but ahead of other models like the BMW i4 and the Audi Q6 e-tron.
GOOD NEWS 🇬🇧 Tesla is absolutely crushing the UK electric vehicle market in 2025 💥
The numbers are in, and the dominance is clear. With an impressive amount of 42,270 vehicles delivered year-to-date, the brand now commands a solid 9.6% market share of the total auto market 🆒… pic.twitter.com/dkiGX9kzd0
— Ming (@tslaming) December 18, 2025
The Model Y has tasted significant success in the global market, but it has dominated in large markets like Europe and the United States.
For years, it’s been a car that has fit the bill of exactly what consumers need: a perfect combination of luxury, space, and sustainability.
Both vehicles are going to see decreases in sales compared to 2024; the Model Y was the best-selling car last year, but it sold 32,610 units in the UK. Meanwhile, the Model 3 had reached 17,272 units, which will keep it right on par with last year.
Tesla sold 50,090 units in the market last year, and it’s about 8,000 units shy of last year’s pace. It also had a stronger market share last year with 13.2 percent of the sales in the market. With two weeks left in 2025, Tesla has a 9.6 percent market share, leading Volkswagen with 8 percent.
The company likely felt some impact from CEO Elon Musk’s involvement with the Trump administration and, more specifically, his role with DOGE. However, it is worth mentioning that some months saw stronger consumer demand than others. For example, sales were up over 20 percent in February. A 14 percent increase followed this in June.
News
Tesla Insurance officially expands to new U.S. state
Tesla’s in-house Insurance program first launched back in late 2019, offering a new way to insure the vehicles that was potentially less expensive and could alleviate a lot of the issues people had with claims, as the company could assess and repair the damage itself.
Tesla Insurance has officially expanded to a new U.S. state, its thirteenth since its launch in 2019.
Tesla has confirmed that its in-house Insurance program has officially made its way to Florida, just two months after the company filed to update its Private Passenger Auto program in the state. It had tried to offer its insurance program to drivers in the state back in 2022, but its launch did not happen.
Instead, Tesla refiled the paperwork back in mid-October, which essentially was the move toward initiating the offering this month.
BREAKING: Tesla Insurance has just officially launched in Florida.
This is the first new state to receive @Tesla Insurance in more than 3 years. In total, Tesla insurance is now available in 13 U.S. states (map in thread below of all the states).
Tesla Insurance in Florida uses… pic.twitter.com/bDwh1IV6gD
— Sawyer Merritt (@SawyerMerritt) December 17, 2025
Tesla’s in-house Insurance program first launched back in late 2019, offering a new way to insure the vehicles that was potentially less expensive and could alleviate a lot of the issues people had with claims, as the company could assess and repair the damage itself.
It has expanded to new states since 2019, but Florida presents a particularly interesting challenge for Tesla, as the company’s entry into the state is particularly noteworthy given its unique insurance landscape, characterized by high premiums due to frequent natural disasters, dense traffic, and a no-fault system.
Annual average premiums for Florida drivers hover around $4,000 per year, well above the national average. Tesla’s insurance program could disrupt this, especially for EV enthusiasts. The state’s growing EV adoption, fueled by incentives and infrastructure development, aligns perfectly with Tesla’s ecosystem.
Moreover, there are more ways to have cars repaired, and features like comprehensive coverage for battery damage and roadside assistance tailored to EVs address those common painpoints that owners have.
However, there are some challenges that still remain. Florida’s susceptibility to hurricanes raises questions about how Tesla will handle claims during disasters.
Looking ahead, Tesla’s expansion of its insurance program signals the company’s ambition to continue vertically integrating its services, including coverage of its vehicles. Reducing dependency on third-party insurers only makes things simpler for the company’s automotive division, as well as for its customers.
Tesla Semi program Director teases major improvements
Tesla dominates in the UK with Model Y and Model 3 leading the way
