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 just gave what is perhaps its biggest signal yet that the launch of the Cybercab, its autonomous ride-hailing-geared car, is imminent.
The Cybercab has been spotted outside of Gigafactory Texas in massive numbers over the past few days, with hundreds of units being stored on property just days after the vehicle received a Certificate of Conformity from the EPA.
Today, things were a bit different.
Cybercabs spotted on Giga Texas property today had an addition: a Cybercab decal on the side, reminiscent of the “Robotaxi” ones that were placed on Model Ys just as the company launched its ride-sharing platform about a year ago.
Giga Texas drone operator Joe Tegtmeyer noticed the change today:
Tesla Cybercabs are now getting “Cybercab” logos on the side of them!
Tesla did the same with Model Ys that were given “Robotaxi” logos: https://t.co/DanANtw1m7 pic.twitter.com/FqOhH0S9Ks
— TESLARATI (@Teslarati) June 19, 2026
Tesla could be signaling that the Cybercab is preparing to enter the Robotaxi fleet in the coming weeks or months with this move. It seems more symbolic than anything; Tesla is ready to throw Cybercabs in the ride-hailing platform just as it did with Model Ys last year.
The addition of the Certificate of Conformity awarded to the Cybercab is another major factor working to Tesla’s advantage. The company now has permission from the EPA to allow the vehicle to operate on public roads and enter the chain of commerce. It’s officially street legal.
Tesla Cybercab specs revealed: range, curb weight, range ratings, and more
The big question that remains is whether Tesla will be able to operate the car without a safety monitor, especially considering it plans to put the car out there without a steering wheel or pedals. With the Cybercab only having a seating capacity of two, it is hard to believe Tesla will even consider putting a Safety Monitor in the car.
It did recently self-certify as Level 4 and has the ability to operate driverless vehicles in the State of Texas under a law that took effect on May 28. You can read more about that here:
Tesla’s Robotaxi dreams just took a massive step toward reality
We’d imagine Cybercabs will be on the roads as soon as July, but August will likely be a better estimate of when the car will be entered into the Cybercab fleet. It all depends at where Tesla is, as they’ve truly prioritized safety with the rollout of the Robotaxi platform.
Elon Musk has publicly questioned Moody’s credit assessments following the rating agency’s decision to assign SpaceX a Baa1 investment-grade rating, two notches above Tesla’s Baa3. The comments came amid discussions comparing the two companies’ financial profiles.
SpaceX earned its first-time Baa1 rating with a stable outlook from Moody’s. The agency highlighted the company’s leadership in orbital launches, the growing recurring revenue from its Starlink satellite network, strong vertical integration, U.S. government contracts, and emerging opportunities in AI infrastructure.
These factors were cited as supporting robust cash flows, margin expansion, and financial flexibility.
Musk responded directly: “Tesla’s credit rating is ridiculously low tbh,” and added, “Yeah, makes no sense. Tesla has over $40B in cash, no debt, and is consistently profitable!” His remarks underscored Tesla’s balance sheet strength and profitability at a time when many traditional automakers continue to report losses in the shift to electric vehicles.
Yeah, makes no sense.
Tesla has over $40B in cash, no debt and is consistently profitable!
— Elon Musk (@elonmusk) June 19, 2026
Tesla maintains a leading position in the global EV market, with diversification into energy and storage, battery technology, and robotics through projects like Optimus. Recent financial updates show the company generated positive free cash flow of $1.4 billion in Q1 2026, supported by operating cash flow of $3.9 billion. Cash and short-term investments stood at approximately $44.7 billion.
Moody’s has affirmed Tesla’s Baa3 issuer rating with a stable outlook in periodic reviews, acknowledging the company’s EV leadership, technology strengths, including AI for autonomous vehicles, solid profitability, and strong liquidity.
Tesla (TSLA) scores Baa3 Moody’s rating for ‘stable’ outlook
However, the agency has also noted challenges in the automotive segment and expectations for margin pressures.
Musk’s critique highlights a common debate about how traditional rating methodologies apply to high-growth, capital-intensive technology companies. SpaceX benefits from long-term government-backed contracts and diversified, recurring revenue streams, while Tesla’s valuation reflects heavy investment in future technologies such as autonomy and robotics.
Both ratings remain investment-grade, yet the one-notch difference has fueled online discussion about potential inconsistencies in evaluating innovative firms.
The exchange comes as SpaceX explores financing options following its recent valuation milestones, while Tesla continues executing on its multi-year roadmap. Musk’s pointed response serves as a reminder that credit ratings, though influential for borrowing costs, represent one lens through which markets assess corporate strength—and that company leaders often view their financial positions through the lens of long-term innovation and cash generation rather than short-term risk metrics alone.
A new report from Reuters claims that a transport authority in Sweden is pushing back against the approval of Tesla’s Full Self-Driving suite because it will travel over speed limits.
The report says the Swedish Transport Administration (TRV) recommends the European Union votes against FSD’s approval. TRV believes it should not be approved until Tesla disables FSD’s ability to speed.
TRV sent a letter to the European Union’s Technical Committee on Motor Vehicles (TCMV), which is set to meet on June 30 to discuss the potential approval of the Tesla FSD suite in the country. Tesla, which has received various approvals in Europe over the past two months, has not provided a comment.
Teslas operating on FSD do travel over the speed limit, depending on the Speed Profile that is chosen. Drivers have the ability to disengage FSD at any point; Tesla specifically states that those supervising the suite are responsible for its actions.
Let’s cut to the chase: humans operating any vehicle speed almost daily in the United States. Realistically, speed limits in the U.S. are more frequently treated as speed minimums. However, other countries are different, and driving behaviors are less aggressive.
TRV believes that “allowing automated systems to systematically exceed legal speed limits…risks undermining both the legal framework and the expected safety benefits of vehicle automation,” the report stated. It’s surprising that Tesla has not received this claim from other countries previously.
This could be a good argument to bring Max Speed back, the setting that previously allowed the driver to choose the absolute fastest the car would travel.
This would still put the responsibility of supervision in the hands of the driver. It would allow the driver to choose whether the car would travel over the speed limit or not, acknowledging that they set the speed, and if they get pulled over, there would be no ability to argue it.
However, it does not seem as if this is something Tesla will do, especially considering many U.S. drivers have requested the feature in an effort to eliminate speeding or at least tone it down. The company has not shown any interest in bringing it back.
Tesla has approvals for FSD in Europe in Estonia, Lithuania, Denmark, the Netherlands, and Belgium.
Tesla Cybercab launch is imminent after latest sighting at Giga Texas
Elon Musk says this part of Tesla ‘makes no sense’
