Science
Bennu asteroid reveals its contents to scientists − and clues to how the building blocks of life on Earth may have been seeded
NASA’s OSIRIS-REx mission returned samples from asteroid Bennu, revealing insights into life’s ingredients on Earth, paralleling those found in the Revelstoke meteorite’s analysis.
Timothy J McCoy, Smithsonian Institution and Sara Russell, Natural History Museum
A bright fireball streaked across the sky above mountains, glaciers and spruce forest near the town of Revelstoke in British Columbia, Canada, on the evening of March 31, 1965. Fragments of this meteorite, discovered by beaver trappers, fell over a lake. A layer of ice saved them from the depths and allowed scientists a peek into the birth of the solar system.
Nearly 60 years later, NASA’s OSIRIS-REx mission returned from space with a sample of an asteroid named Bennu, similar to the one that rained rocks over Revelstoke. Our research team has published a chemical analysis of those samples, providing insight into how some of the ingredients for life may have first arrived on Earth.
Born in the years bracketing the Revelstoke meteorite’s fall, the two of us have spent our careers in the meteorite collections of the Smithsonian Institution in Washington, D.C., and the Natural History Museum in London. We’ve dreamed of studying samples from a Revelstoke-like asteroid collected by a spacecraft.
Then, nearly two decades ago, we began turning those dreams into reality. We joined NASA’s OSIRIS-REx mission team, which aimed to send a spacecraft to collect and return an asteroid sample to Earth. After those samples arrived on Sept. 24, 2023, we got to dive into a tale of rock, ice and water that hints at how life could have formed on Earth.
The CI chondrites and asteroid Bennu
To learn about an asteroid – a rocky or metallic object in orbit around the Sun – we started with a study of meteorites.
Asteroids like Bennu are rocky or metallic objects in orbit around the Sun. Meteorites are the pieces of asteroids and other natural extraterrestrial objects that survive the fiery plunge to the Earth’s surface.
We really wanted to study an asteroid similar to a set of meteorites called chondrites, whose components formed in a cloud of gas and dust at the dawn of the solar system billions of years ago.
The Revelstoke meteorite is in a group called CI chondrites. Laboratory-measured compositions of CI chondrites are essentially identical, minus hydrogen and helium, to the composition of elements carried by convection from the interior of the Sun and measured in the outermost layer of the Sun. Since their components formed billions of years ago, they’re like chemically unchanged time capsules for the early solar system.
So, geologists use the chemical compositions of CI chondrites as the ultimate reference standard for geochemistry. They can compare the compositions of everything from other chondrites to Earth rocks. Any differences from the CI chondrite composition would have happened through the same processes that formed asteroids and planets.
CI chondrites are rich in clay and formed when ice melted in an ancient asteroid, altering the rock. They are also rich in prebiotic organic molecules. Some of these types of molecules are the building blocks for life.
This combination of rock, water and organics is one reason OSIRIS-REx chose to sample the organic-rich asteroid Bennu, where water and organic compounds essential to the origin of life could be found.
Evaporites − the legacy of an ancient brine
Ever since the Bennu samples returned to Earth on Sept. 24, 2023, we and our colleagues on four continents have spent hundreds of hours studying them.
The instruments on the OSIRIS-REx spacecraft made observations of reflected light that revealed the most abundant minerals and organics when it was near asteroid Bennu. Our analyses in the laboratory found that the compositions of these samples lined up with those observations.
The samples are mostly water-rich clay, with sulfide, carbonate and iron oxide minerals. These are the same minerals found in CI chondrites like Revelstoke. The discovery of rare minerals within the Bennu samples, however, surprised both of us. Despite our decades of experience studying meteorites, we have never seen many of these minerals.
We found minerals dominated by sodium, including carbonates, sulfates, chlorides and fluorides, as well as potassium chloride and magnesium phosphate. These minerals don’t form just when water and rock react. They form when water evaporates.
We’ve never seen most of these sodium-rich minerals in meteorites, but they’re sometimes found in dried-up lake beds on Earth, like Searles Lake in California.
Bennu’s rocks formed 4.5 billion years ago on a larger parent asteroid. That asteroid was wet and muddy. Under the surface, pockets of water perhaps only a few feet across were evaporating, leaving the evaporite minerals we found in the sample. That same evaporation process also formed the ancient lake beds we’ve seen these minerals in on Earth.
Bennu’s parent asteroid likely broke apart 1 to 2 billion years ago, and some of the fragments came together to form the rubble pile we know as Bennu.
These minerals are also found on icy bodies in the outer solar system. Bright deposits on the dwarf planet Ceres, the largest body in the asteroid belt, contain sodium carbonate. The Cassini mission measured the same mineral in plumes on Saturn’s moon Enceladus.
We also learned that these minerals, formed when water evaporates, disappear when exposed to water once again – even with the tiny amount of water found in air. After studying some of the Bennu samples and their minerals, researchers stored the samples in air. That’s what we do with meteorites.
Unfortunately, we lost these minerals as moisture in the air on Earth caused them to dissolve. But that explains why we can’t find these minerals in meteorites that have been on Earth for decades to centuries.
Fortunately, most of the samples have been stored and transported in nitrogen, protected from traces of water in the air.
Until scientists were able to conduct a controlled sample return with a spacecraft and carefully curate and store the samples in nitrogen, we had never seen this set of minerals in a meteorite.
An unexpected discovery
Before returning the samples, the OSIRIS-REx spacecraft spent over two years making observations around Bennu. From that two years of work, researchers learned that the surface of the asteroid is covered in rocky boulders.
We could see that the asteroid is rich in carbon and water-bearing clays, and we saw veins of white carbonate a few feet long deposited by ancient liquid water. But what we couldn’t see from these observations were the rarer minerals.
We used an array of techniques to go through the returned sample one tiny grain at a time. These included CT scanning, electron microscopy and X-ray diffraction, each of which allowed us to look at the rock at a scale not possible on the asteroid.
Cooking up the ingredients for life
From the salts we identified, we could infer the composition of the briny water from which they formed and see how it changed over time, becoming more sodium-rich.
This briny water would have been an ideal place for new chemical reactions to take place and for organic molecules to form.
While our team characterized salts, our organic chemist colleagues were busy identifying the carbon-based molecules present in Bennu. They found unexpectedly high levels of ammonia, an essential building block of the amino acids that form proteins in living matter. They also found all five of the nucleobases that make up part of DNA and RNA.
Based on these results, we’d venture to guess that these briny pods of fluid would have been the perfect environments for increasingly complicated organic molecules to form, such as the kinds that make up life on Earth.
When asteroids like Bennu hit the young Earth, they could have provided a complete package of complex molecules and the ingredients essential to life, such as water, phosphate and ammonia. Together, these components could have seeded Earth’s initially barren landscape to produce a habitable world.
Without this early bombardment, perhaps when the pieces of the Revelstoke meteorite landed several billion years later, these fragments from outer space would not have arrived into a landscape punctuated with glaciers and trees.
Timothy J McCoy, Supervisory Research Geologist, Smithsonian Institution and Sara Russell, Professor of Planetary Sciences, Natural History Museum
This article is republished from The Conversation under a Creative Commons license. Read the original article.
News
Joby Aviation and Toyota kick off manufacturing alliance to scale electric air taxi production
Joby Aviation and Toyota launch a joint venture to improve productivity, quality, and cost as they prepare to scale electric air taxi production.
Joby Aviation and Toyota Motor Corporation have launched the initial phase of a strategic manufacturing alliance aimed at accelerating commercial production of electric air taxis—an early step the companies say is designed to make “air mobility for all” a practical, everyday reality.
Announced June 30, 2026, the partnership formalizes a new joint venture that will combine Joby’s electric aviation development with Toyota’s production systems and operational expertise. The near-term focus: building the groundwork for commercial production while pushing improvements in productivity, quality, and cost—key factors as the industry moves from prototypes to scaled manufacturing.
What the joint venture is designed to do
According to the companies, the alliance will initially concentrate on:
- Establishing the foundation for commercial production capability
- Advancing manufacturing excellence with an emphasis on productivity, quality, and cost
- Supporting expansion of Joby’s production capacity as it works toward aircraft certification and prepares for anticipated demand
The announcement positions Toyota’s manufacturing playbook—known globally for lean production and continuous improvement—as a lever to help Joby move from development into repeatable, high-quality output at scale.
Why it matters: eVTOLs need scale, not just flight tests
Electric vertical take-off and landing (eVTOL) aircraft have become one of the most closely watched bets in next-generation transportation, but the path to viable air taxi services depends on more than successful test flights. Certification timelines, supply chain readiness, and the ability to produce aircraft consistently (and affordably) are often what separates promising technology from commercial reality.
By forming a joint venture focused on manufacturing readiness, Joby and Toyota are signaling that the next competitive frontier is industrialization—how quickly and reliably eVTOL aircraft can be built to meet safety standards and market demand.
Related Links for Further reading
- Joby Aviation (official): https://www.jobyaviation.com
- Joby Investor Relations / News (official updates & filings): https://ir.jobyaviation.com
- Toyota Newsroom (official): https://www.toyotanewsroom.com
- Toyota Global (corporate overview): https://global.toyota/en
- FAA Advanced Air Mobility / Air Taxis (context): https://www.faa.gov/air-taxis
What executives are saying
Joby founder and CEO JoeBen Bevirt emphasized the long-running relationship between the companies, calling the joint venture a reflection of shared confidence in the opportunity ahead.
“Toyota has been by Joby’s side for nearly a decade, providing invaluable guidance and support as we built the foundation for manufacturing our aircraft,” Bevirt said. “Together, we share a vision of making aerial mobility an everyday reality.”
Toyota Motor Corporation Chairman Akio Toyoda framed air mobility as an extension of the company’s broader mission.
“Since our founding, we’ve been guided by the philosophy of providing mobility for all,” Toyoda said, adding that Toyota views air mobility as “a natural extension of that philosophy—from the ground into the sky.”
About the companies
Joby Aviation (NYSE: JOBY) is a California-based transportation company developing an all-electric eVTOL air taxi. The company intends to operate its own air taxi service in cities worldwide and sell aircraft to other operators and partners.
Toyota (NYSE: TM) has operated in North America for nearly 70 years and says it is focused on sustainable, next-generation mobility through Toyota and Lexus brands. Toyota reports nearly 64,000 employees in North America, 14 manufacturing plants, and more than 1,800 dealerships. The company also noted that its North Carolina plant began assembling automotive batteries for electrified vehicles in 2025.
What to watch for next
For readers tracking the air taxi sector, the next milestones will likely center on:
- Details on how the joint venture will be structured operationally
- Updates on Joby’s certification progress and production ramp timelines
- Signs of how manufacturing improvements translate into cost reductions and throughput
- Additional agreements or expanded collaboration as the alliance progresses
While the companies highlighted expected benefits, they also noted the usual forward-looking risks—such as regulatory certification timelines, market conditions, and the ability to finalize additional agreements.
Source: Toyota Motor North America / PRNewswire (June 30, 2026)
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STM Blog
From Hand Signals to Smart Crosswalks: The Evolution of the Modern Pedestrian Signal
Discover the history of the modern pedestrian signal, from Garrett A. Morgan’s groundbreaking traffic signal to today’s smart, accessible crosswalks.
Last Updated on July 12, 2026 by Daily News Staff
Every day, millions of people rely on pedestrian signals to cross busy street safely. A glowing white walking figure, an orange-red hand, and a countdown timer have become familiar sights around the world. While these signals may seem like simple pieces of infrastructure, they are the result of more than a century of innovation, engineering, and public safety improvements.
The modern pedestrian signal did not appear overnight. Instead, it evolved through the contributions of inventors, engineers, city planners, and transportation officials who continually refined traffic control systems as cities grew and automobiles became more common.
The Early Days of Traffic Control
Before electric traffic signals, intersections were controlled by police officers, railway-style semaphores, or even hand signals. As horse-drawn wagons gave way to automobiles in the early 1900s, traffic congestion and accidents increased dramatically, creating an urgent need for better traffic management.
One of the earliest electric traffic lights was installed in Cleveland, Ohio, in 1914. It used red and green lights and was manually operated. While it improved vehicle movement, pedestrians still had to judge for themselves when it was safe to cross.
Garrett A. Morgan’s Breakthrough
One of the most important milestones came in 1923 when inventor and entrepreneur Garrett Augustus Morgan received U.S. Patent No. 1,475,024 for an improved traffic signal.
Morgan’s design introduced a third position in addition to “Stop” and “Go.” This intermediate phase temporarily stopped traffic in every direction before allowing vehicles to proceed. The brief pause reduced confusion at intersections and provided additional time for pedestrians to cross safely.
Morgan reportedly developed his design after witnessing a serious traffic accident. His invention demonstrated how thoughtful engineering could improve public safety while making increasingly busy streets more efficient.
Although Morgan did not invent the illuminated “WALK” and “DON’T WALK” pedestrian signal used today, his three-position signal became a foundational step in the evolution of modern traffic control.
The Birth of Dedicated Pedestrian Signals
As cities expanded after World War II, pedestrian safety became an even greater concern. More people were walking in increasingly crowded downtown districts, and separating pedestrian movements from vehicle traffic became a priority.
During the early 1950s, several American cities began experimenting with dedicated pedestrian signals. New York City became one of the first major municipalities to install illuminated “WALK” and “DON’T WALK” signs at busy intersections.
These early systems gave pedestrians their own designated crossing phase, reducing conflicts with turning vehicles and improving safety at some of the nation’s busiest intersections.
Standardization Across America
By the 1960s and 1970s, traffic engineers recognized the importance of creating consistent traffic control devices nationwide.
The Manual on Uniform Traffic Control Devices (MUTCD) established national standards for traffic signs, pavement markings, and pedestrian signals. Standardized designs helped ensure that pedestrians could understand crossing signals regardless of where they traveled in the United States.
Eventually, words gave way to internationally recognized symbols—a walking person to indicate it was safe to cross and an upraised hand to indicate pedestrians should wait. These symbols transcended language barriers and improved accessibility for visitors and non-English speakers.
The Countdown Era
One of the most significant modern improvements arrived with pedestrian countdown timers.
Rather than simply flashing a warning, countdown displays show exactly how many seconds remain before the crossing phase ends. Research has shown that countdown timers help pedestrians make better crossing decisions and improve compliance with traffic signals.
Today, countdown timers have become standard equipment at intersections across much of the United States.
Accessibility Takes Center Stage
Modern pedestrian signals are designed to serve everyone.
Accessible Pedestrian Signals (APS) now provide audible tones, spoken messages, vibrating push buttons, and locator sounds that assist pedestrians who are blind or have low vision. These features allow more people to navigate intersections independently and safely.
The continued development of accessible technology reflects a broader commitment to making transportation systems inclusive for all users.
The Future of Pedestrian Safety
Pedestrian signals continue to evolve.
Many cities now use smart traffic systems that detect pedestrians waiting to cross, automatically adjust signal timing based on traffic conditions, and prioritize people walking during busy periods.
Researchers are exploring artificial intelligence, connected vehicle technology, and sensor-based systems capable of communicating directly with autonomous vehicles. Future pedestrian crossings may adapt in real time to weather conditions, crowd sizes, emergency vehicles, and even the needs of older adults or individuals with disabilities.
A Legacy Built by Many Innovators
The pedestrian signal we know today is the product of more than a century of collaboration and innovation.
Early traffic engineers created the first electric traffic lights. Garrett A. Morgan improved intersection safety with his groundbreaking three-position traffic signal. Transportation agencies standardized traffic control devices, while engineers continued refining pedestrian technology through countdown timers, accessible features, and intelligent traffic systems.
Every safe crossing today reflects the work of countless inventors, planners, researchers, and public officials dedicated to protecting lives.
As cities continue to grow and transportation technology advances, the humble pedestrian signal remains one of the most effective—and often overlooked—public safety innovations ever developed.
At STM Daily News, we celebrate the inventors, engineers, and visionaries whose everyday innovations quietly improve life for millions of people. Sometimes the most important inventions aren’t the ones that grab headlines—they’re the ones we depend on every single day without giving them a second thought.
Related Reading
- Federal Highway Administration – Manual on Uniform Traffic Control Devices (MUTCD)
- National Museum of African American History and Culture – Garrett Augustus Morgan
- United States Patent and Trademark Office
- Federal Highway Administration – Accessible Pedestrian Signals
- National Highway Traffic Safety Administration (NHTSA)
🧠 Discover the remarkable innovators, inventors, and trailblazers who helped shape our world but rarely receive the recognition they deserve. Share your thoughts in the comments and subscribe to the STM Daily News newsletter to catch every new Forgotten Genius Friday feature and more inspiring stories delivered to your inbox.
The Earth
Cement has a climate problem — here’s how geopolymers with add‑ins like cork could help fix it
Portland cement drives ~8% of global emissions. Learn how low-carbon geopolymers—enhanced with add-ins like cork—could cut concrete’s footprint.
Alcina Johnson Sudagar, Washington University in St. Louis
Concrete is all around you – in the foundation of your home, the bridges you drive over, the sidewalks and buildings of cities. It is often described as the second-most used material by volume on Earth after water.
But the way concrete is made today also makes it a major contributor to climate change.
Portland cement, the key component of concrete, is responsible for about 8% of global greenhouse gas emissions. That’s because it’s made by heating limestone to high temperatures, a process that burns a large amount of fossil fuels for energy and releases carbon dioxide from the limestone in the process.
The good news is that there are alternatives, and they are gaining attention.
Portland cement: A greenhouse gas problem
Cementlike substances have been used in construction for thousands of years. Architects have found evidence of their use in the pyramids of Egypt and the buildings and aqueducts of the Roman Empire.
The Portland cement commonly used in construction today was patented in 1824 by Joseph Aspdin, a British bricklayer.
Modern cement preparation starts with crushing the excavated raw materials limestone and clay and then heating them in a kiln at around 2,650 degrees Fahrenheit (about 1,450 degrees Celsius) to form clinker, a hard, rocklike residue. The clinker is then cooled and ground with gypsum into a fine powder, which is called cement.
About 40% of the carbon dioxide emissions from cement production come from burning fossil fuels to generate the high heat needed to run the kiln. The rest come as the heat converts limestone (calcium carbonate) to lime (calcium oxide), releasing carbon dioxide.
In all, between half a ton and 1 ton of greenhouse gas is released per ton of Portland cement. Cement is a binding agent that, mixed with water, holds aggregate together to create concrete. It makes up about 10% to 15% of the concrete mix by weight.
Alternative technologies can lower emissions
As populations, cities and the need for new infrastructure expand, the use of cement is growing, making it important to find alternatives with lower environmental costs.
Some techniques for reducing carbon dioxide emissions include substituting some of the clinker – the hard residue typically made from limestone – with supplementary materials such as clay, or fly ash and slag from industries. Other methods reduce the amount of cement by mixing in waste sawdust or recycled materials like plastics.
The long-term solution for reducing cement’s emissions, however, is to replace traditional cement completely with alternatives. One option is geopolymers made from earthen clay and industrial wastes.
Geopolymers: A more climate-friendly solution
Geopolymers can be made by mixing claylike materials that are rich in aluminum and silicon minerals with a chemical activator through a process called geopolymerization. The activator transforms the silicon and aluminum into a structure that will look like cement. All of this can happen at room temperature.
The major difference between cement and geopolymer is that cement is mainly made of calcium, whereas geopolymers are made of silicon and aluminum with some possible calcium in their structure.
These geopolymers have been found to possess high strength and durability, including resilience in freeze-thaw cycles and resistance to heat and fire, which are important requirements in construction. Studies have found that some geopolymers can provide comparable if not better strength than traditional cement and, because they don’t require heat the way clinker does, they can be produced with significantly lower greenhouse gas emissions.
Geopolymers can also be produced from a variety of raw materials rich in aluminum and silicon, including earthen clays, fly ash, blast furnace slag, rice husk ash, iron ore wastes and recycled construction brick waste. Geopolymer technology can be adapted depending on the clay or industrial waste locally available in a region. https://www.youtube.com/embed/NOj3p6m9M7Q?wmode=transparent&start=0 A brief history of cement and geopolymers. Geopolymer International.
An added advantage of geopolymers is that changes to the mixture can produce a range of features.
For example, I and my co-researchers at the University of Aveiro in Portugal added a small amount of cork industry waste – the leftovers from creating bottle corks – to clay-based geopolymer and found it could improve the strength of the material by up to twofold. The cork particles filled the spaces in the geopolymer structure, making it denser, which increased the strength.
Similarly, additives such as sisal fibers from the agave plant, recycled plastic and steel fibers can change geopolymer properties. The additives do not participate in the geopolymerization process but act as fillers in the structure.
The structure of geopolymers can also be designed to act as adsorbents, attracting toxic metals in wastewater and capturing and storing radioactive wastes. Specifically, incorporating materials like zeolite that are natural adsorbents in the geopolymer structure can make them useful for such applications as well.
Where geopolymers are used now
Geopolymers have been used in many types of construction, including roads, coatings, 3D printing, coastal environmental protection, the steel and chemical industries, sewer rehabilitation and building radiation shielding and rocket launchpad and bunker infrastructure.
One of the earliest examples of a modern geopolymer concrete project was the Brisbane West Wellcamp airport in Australia.
It was built in 2014 with 70,000 metric tons of geopolymer concrete, which was estimated to have reduced the project’s carbon dioxide emissions by as much as 80%.
The geopolymer market is currently estimated to be between US$7 billion and $10 billion, with the largest growth in the Asia-Pacific region.
Analysts have estimated that the market could grow at a rate of 10% to 20% per year and reach about $62 billion by 2033.
In several countries, greenhouse gas regulations and green-building certifications are expected to support the continued growth of geopolymers in the construction industry.
Expanding the use of cement alternatives
The advantage of using industrial wastes in geopolymers is a double-edged sword, however. The composition of industrial wastes varies, so it can be difficult to standardize the processing methods. The geopolymer components need to be mixed in particular ratios to achieve desired properties.
Producing the activator for the geopolymer, typically done in chemical facilities, can raise the cost and contribute to the carbon footprint. And the long-term data about these materials’ stability is only now being developed given their newness. Also, these geopolymers can take longer to set than cement, though the setting time can be sped up by using raw materials that react quickly.
Developing cheaper, naturally available activators like agricultural waste rice husk with sustainable supply chains could help lower the costs and environmental impact. Also, printing the recipe on the raw material packaging could help simplify the job of determining the mixing ratio so geopolymers can be more widely used with confidence.
Even though geopolymer technology has some drawbacks, these low-carbon alternatives have great potential for reducing emissions from the construction sector.
Alcina Johnson Sudagar, Research Scientist in Chemistry, Washington University in St. Louis
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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