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 stock tumbles after earnings, one of its sharpest single-day declines
Tesla stock (NASDAQ: TSLA) endured one of its sharpest single-day declines in years on July 23, tumbling approximately 14.5 percent and closing near $320 after opening the session around $374. The drop erased more than $140 billion in market value amid heavy trading volume and left the shares at multi-week lows.
The sell-off followed the company’s second-quarter 2026 results, released the previous evening. Tesla reported record revenue of $28.2 billion, up 26 percent year over year, driven by a Q2-record 480,126 vehicle deliveries. Energy storage deployments also rose strongly.
Tesla (TSLA) Q2 2026 earnings results: miss on EPS, beat on revenue
Yet profitability disappointed sharply. Operating income fell 57 percent to $398 million, compressing the operating margin to just 1.4 percent. Non-GAAP earnings per share came in at $0.33, well below the roughly $0.53 analysts had expected. Free cash flow turned negative by $1.1 billion as capital expenditures surged 142 percent to $5.8 billion, largely tied to accelerated spending on artificial intelligence, robotics, and autonomous systems.
The losses on capex were expected, as Tesla said it would be spending heavily in 2026.
Investors also reacted to lingering uncertainty surrounding key product timelines. During the Earnings Call, management reiterated ambitions for Robotaxi deployment and the Optimus humanoid robot, but offered limited new concrete milestones, renewing questions about execution pace that have long accompanied Tesla’s ambitious roadmap.
The magnitude of the decline places it among Tesla’s more severe one-day percentage losses since its 2010 initial public offering. Historically, the two largest single-day drops (split-adjusted) remain September 8, 2020, when shares fell 21.1 percent amid broader market volatility and valuation concerns, and January 13, 2012, with a 19.3 percent plunge during the company’s early growth struggles.
Other notable declines include an 18.6 percent drop on March 16, 2020, at the onset of pandemic-related market turmoil. Thursday’s move ranks roughly ninth on the all-time list but stands out as the steepest in more than a year.
Despite the short-term pain, Tesla’s long-term trajectory has repeatedly recovered from such volatility. The latest results underscore both the strength of its core automotive and energy businesses and the near-term costs of heavy investment in next-generation technologies.
Elon Musk
Elon Musk is not happy about this Tesla Full Self-Driving approval delay
Elon Musk clapped back at France’s decision to withhold the approval for Tesla’s Full Self-Driving (FSD) Supervised system, projecting a clear and blunt message to French Transport Minister Phillippe Tabarot, after he publicly rejected the technology in its current form.
Tabarot outlines several concerns with Tesla Full Self-Driving in a detailed video statement, where he said, “The safety trade-offs are not yet sufficient to authorize it as it currently stands,” he said. He emphasized that FSD is not a true self-driving system and that the driver remains fully responsible.
Key issues Tabarot also brought up included allowing speeding when surrounding traffic exceeds limits and what he believes are insufficient guarantees of driver attention during complex urban maneuvers such as lane changes, intersections, and roundabouts.
Delaying the approval of FSD in France will cost lives
— Elon Musk (@elonmusk) July 22, 2026
While acknowledging technological progress and France’s support for autonomous innovation, Tabarot stressed that deployment must prioritize road safety. He noted ongoing technical discussions with Tesla, the Netherlands, and other European partners, with further ecosystem meetings planned for the fall.
Musk’s rebuke highlights the human cost of regulatory caution. Tesla’s latest safety reports provide compelling data supporting accelerated adoption. In the most recent 12-month period, vehicles using FSD (Supervised) recorded one major collision per approximately 5.1 million miles driven, dramatically better than the U.S. national average of one crash per 698,000 miles.
Even Tesla vehicles driven manually with active safety features outperform the average by a wide margin. These figures come from billions of real-world miles of telemetry, showing FSD vehicles involved in far fewer incidents than both manual Teslas and the broader U.S. fleet.
Critics argue Tesla’s comparisons require careful scrutiny regarding reporting thresholds and fleet demographics, yet the data consistently positions FSD as a potential lifesaver. With road fatalities remaining a leading cause of death worldwide, Musk contends that proven safer technology should not face prolonged bureaucratic hurdles.
France’s measured approach reflects the broader European regulatory caution, which many, especially Musk, have been critical of in the past. However, as autonomous systems from Tesla and competitors like Waymo demonstrate superior safety in independent studies, pressure is mounting for harmonized approvals.
Musk’s warning carries the belief that every month of delay may equate to avoidable tragedies on European roads.
Investor's Corner
Google’s massive stake in SpaceX will shock you
In a striking revelation that underscores the lucrative crossover between Big Tech and space exploration, Alphabet Inc., Google’s parent company, disclosed a massive $94.1 billion equity stake in SpaceX following the rocket company’s blockbuster initial public offering earlier this year.
The disclosure came in Alphabet’s quarterly filing, marking the first time the long-held private investment has been publicly valued at market prices. Google was an early backer, investing alongside Fidelity in 2015 with roughly $500-900 million at a time when SpaceX was valued around $12 billion.
That bet has delivered extraordinary returns, roughly a hundredfold, transforming a strategic play on satellite internet and launch capabilities into one of Alphabet’s largest assets.
Google, $GOOGL, has said they hold $94 billion in SpaceX, $SPCX, shares after IPO.
— unusual_whales (@unusual_whales) July 23, 2026
Of the total holding, approximately $80 billion remains subject to short-term post-IPO lockup restrictions, preventing near-term sales. An additional $14.1 billion faces longer-term restrictions, extending into the third quarter of 2027. This structure limits immediate liquidity but protects against market volatility as SpaceX transitions into public trading.
The SpaceX position contributed significantly to gains in Alphabet’s broader investment portfolio, which also includes a major stake in AI leader Anthropic. Combined, these holdings helped drive nearly $100 billion in investment gains during the second quarter, providing a substantial boost to net income amid ongoing AI spending pressures.
Analysts view the disclosure as validation of Alphabet’s venture strategy beyond its core search and cloud businesses. The investment aligns with deeper ties, including reported multi-billion-dollar deals for AI computing capacity on SpaceX infrastructure. As SpaceX advances Starship flights, Starlink expansion, and ambitious Mars goals under Elon Musk, Google’s stake positions it to benefit from the commercialization of space.
For Alphabet, the windfall highlights how patient, forward-looking bets in transformative sectors can yield outsized rewards. While lockups temper short-term impact, the holding cements SpaceX as a cornerstone of Alphabet’s diversified portfolio in an era where aerospace, AI, and connectivity increasingly intersect. Investors will watch closely as restrictions lift and SpaceX’s public performance unfolds.