Europa, a moon of Jupiter, has long been one of the most exciting targets in the search for life beyond Earth. Many scientists believe that an ocean lies below its icy surface, potentially hosting geologic activity capable of supporting life, but what happens on the moon’s seafloor is still largely a mystery. Although discussions on Europa are mostly centered around this hidden ocean, the shell of ice that envelops the moon has its own surprises. A study recently published in The Planetary Science Journal suggests that Europa’s surface ice is constantly changing. The evidence explored in the study paints a better picture of Europa’s outermost layer, and it may even reveal the interior processes that shape the moon’s unique structure. Europa's Surface IceEuropa has the smoothest surface out of any known object in our Solar System, but it’s far from lacking variety. The surface is rife with distinct geologic features, such as ridges, plains, and cracks, that cross over each other. Their disorderly appearance is linked to a fitting name, “chaos terrain.”Some regions with chaos terrain also provide insight on Europa’s surface ice. Most of Europa’s surface is made of amorphous ice, which lacks a crystalline structure. Scientists previously believed that Europa’s surface was entirely covered by a thin layer of amorphous ice, and that below this was crystalline ice (the form that most ice on Earth takes). However, the researchers involved with the new study have confirmed that certain areas of Europa’s surface contain crystalline ice, aligning with spectral data captured by the James Webb Space Telescope (JWST). This same ice also appears below the surface in these regions as well. “We think that the surface is fairly porous and warm enough in some areas to allow the ice to recrystallize rapidly,” said lead author Richard Cartwright, a spectroscopist at Johns Hopkins University, in a statement.Activity in the OceanA few other factors have convinced the researchers that an ocean exists below Europa's icy surface. The regions where ice recrystallizes show evidence of sodium chloride (what we know as table salt), carbon dioxide, and hydrogen peroxide. “Our data showed strong indications that what we are seeing must be sourced from the interior, perhaps from a subsurface ocean nearly 20 miles (30 kilometers) beneath Europa’s thick icy shell,” said author Ujjwal Raut, a program manager at the Southwest Research Institute. “This region of fractured surface materials could point to geologic processes pushing subsurface materials up from below.”The Europa Clipper's MissionAlthough Europa and its subsurface ocean will be a crucial target for future space exploration, some scientists have expressed doubts regarding its capacity to sustain life. A series of obstacles could make finding life on Europa more difficult. At an American Geophysical Union conference last year, scientists reported that the ice layer covering the moon's surface is thicker than expected, indicating that there may not be enough heat or activity in the subsurface ocean to support life. Scientists aren’t yet sure if an abundance of hydrothermal vents or seafloor volcanoes sit at the bottom of the ocean — these features have been crucial in driving life on our own planet. Observations of Europa haven’t fully confirmed the existence of plumes, either, which would be a clear sign that material from the ocean could be transported to the surface. About 5 years from now, in 2030, scientists will get an unprecedented view of Europa as NASA's Europa Clipper approaches the icy moon. Launched last October, the Europa Clipper will reveal many secrets that still surround the moon's surface and the ocean below. Among its various objectives, the mission will look for plumes, which would be able to eject microbes — if they truly do exist on the moon — into space for the Europa Clipper to examine. Article SourcesOur writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:The Planetary Science Journal. JWST Reveals Spectral Tracers of Recent Surface Modification on EuropaThe Planetary Society. Europa, Jupiter’s possible watery moonThe Planetary Society. Could Europa Clipper find life?Jack Knudson is an assistant editor at Discover with a strong interest in environmental science and history. Before joining Discover in 2023, he studied journalism at the Scripps College of Communication at Ohio University and previously interned at Recycling Today magazine.

A new type of fuel cell that runs on sodium metal could one day help clean up sectors where it’s difficult to replace fossil fuels, like rail, regional aviation, and short-distance shipping. The device represents a departure from technologies like lithium-based batteries and is more similar conceptually to hydrogen fuel cell systems.  The sodium-air fuel cell was designed by a team led by Yet-Ming Chiang, a professor of materials science and engineering at MIT. It has a higher energy density than lithium-ion batteries and doesn’t require the super-cold temperatures or high pressures that hydrogen does, making it potentially more practical for transport. “I’m interested in sodium metal as an energy carrier of the future,” Chiang says.   The device’s design, published today in Joule, is related to the technology behind one of Chiang’s companies, Form Energy, which is building iron-air batteries for large energy storage installations like those that could help store wind and solar power on the grid. Form’s batteries rely on water, iron, and air. One technical challenge for metal-air batteries has historically been reversibility. A battery’s chemical reactions must be easily reversed so that in one direction they generate electricity, discharging the battery, and in the other electricity goes into the cell and the reverse reactions happen, charging it up. When a battery’s reactions produce a very stable product, it can be difficult to recharge the battery without losing capacity. To get around this problem, the team at Form had discussions about whether their batteries could be refuelable rather than rechargeable, Chiang says. The idea was that rather than reversing the reactions, they could simply run the system in one direction, add more starting material, and repeat.  Ultimately, Form chose a more traditional battery concept, but the idea stuck with Chiang, who decided to explore it with other metals and landed on the idea of a sodium-based fuel cell.  In this fuel cell format, the device takes in chemicals and runs reactions that generate electricity, after which the products get removed. Then fresh fuel is put in to run the whole thing again—no electrical charging required. (You might recognize this concept from hydrogen fuel cell vehicles, like the Toyota Mirai.) Chiang and his colleagues set out to build a fuel cell that runs on liquid sodium, which could have a much higher energy density than existing commercial technologies, so it would be small and light enough to be used for things like regional airplanes or short-distance shipping. Sodium metal could be used to power regional planes or short distance shipping.GRETCHEN ERTL/MITTR The research team built small test cells to try out the concept and ran them to show that they could use the sodium-metal-based system to generate electricity. Since sodium becomes liquid at about 98 °C (208 °F), the cells operated at moderate temperatures of between 110 °C and 130 °C (or 230 °F and 266°F), which could be practical for use on planes or ships, Chiang says.  From their work with these experimental devices, the researchers estimated that the energy density was about 1,200 watt-hours per kilogram (Wh/kg). That’s much higher than what commercial lithium-ion batteries can reach today (around 300 Wh/kg). Hydrogen fuel cells can achieve high energy density, but that requires the hydrogen to be stored at high pressures and often ultra-low temperatures. “It’s an interesting cell concept,” says Jürgen Janek, a professor at the Institute of Physical Chemistry at the University of Giessen in Germany, who was not involved in the research. There’s been previous research on sodium-air batteries in the past, Janek says, but using this sort of chemistry in a fuel cell instead is new. “One of the critical issues with this type of cell concept is the safety issue,” Janek says. Sodium metal reacts very strongly with water. (You may have seen videos where blocks of sodium metal get thrown into a lake, to dramatic effect). Asked about this issue, Chiang says the design of the cell ensures that water produced during reactions is continuously removed, so there’s not enough around to fuel harmful reactions. The solid electrolyte, a ceramic material, also helps prevent reactions between water and sodium, Chiang adds.  Another question is what happens to one of the cell’s products, sodium hydroxide. Commonly known as lye, it's an industrial chemical, used in products like liquid drain-cleaning solution. One of the researchers’ suggestions is to dilute the product and release it into the atmosphere or ocean, where it would react with carbon dioxide, capturing it in a stable form and preventing it from contributing to global warming. There are groups pursuing field trials using this exact chemical for ocean-based carbon removal, though some have been met with controversy. The researchers also laid out the potential for a closed system, where the chemical could be collected and sold as a by-product. There are economic factors working in favor of sodium-based systems, though it would take some work to build up the necessary supply chains. Today, sodium metal isn’t produced at very high volumes. However, it can be made from sodium chloride (table salt), which is incredibly cheap. And it was produced more abundantly in the past, since it was used in the process of making leaded gasoline. So there’s a precedent for a larger supply chain, and it’s possible that scaling up production of sodium metal would make it cheap enough to use in fuel cell systems, Chiang says. Chiang has cofounded a company called Propel Aero to commercialize the research. The project received funding from ARPA-E’s Propel-1K program, which aims to develop new forms of high-power energy storage for aircraft, trains, and ships. The next step is to continue research to improve the cells’ performance and energy density, and to start designing small-scale systems. One potential early application is drones. “We’d like to make something fly within the next year,” Chiang says. “If people don’t find it crazy, I’ll be rather disappointed,” Chiang says. “Because if an idea doesn’t sound crazy at the beginning, it probably isn’t as revolutionary as you think. Fortunately, most people think I’m crazy on this one.”

A new type of fuel cell that runs on sodium metal could one day help clean up sectors where it’s difficult to replace fossil fuels, like rail, regional aviation, and short-distance shipping. The device represents a departure from technologies like lithium-based batteries and is more similar conceptually to hydrogen fuel cell systems.  The sodium-air fuel cell was designed by a team led by Yet-Ming Chiang, a professor of materials science and engineering at MIT. It has a higher energy density than lithium-ion batteries and doesn’t require the super-cold temperatures or high pressures that hydrogen does, making it potentially more practical for transport. “I’m interested in sodium metal as an energy carrier of the future,” Chiang says.   The device’s design, published today in Joule, is related to the technology behind one of Chiang’s companies, Form Energy, which is building iron-air batteries for large energy storage installations like those that could help store wind and solar power on the grid. Form’s batteries rely on water, iron, and air. One technical challenge for metal-air batteries has historically been reversibility. A battery’s chemical reactions must be easily reversed so that in one direction they generate electricity, discharging the battery, and in the other electricity goes into the cell and the reverse reactions happen, charging it up. When a battery’s reactions produce a very stable product, it can be difficult to recharge the battery without losing capacity. To get around this problem, the team at Form had discussions about whether their batteries could be refuelable rather than rechargeable, Chiang says. The idea was that rather than reversing the reactions, they could simply run the system in one direction, add more starting material, and repeat.  Ultimately, Form chose a more traditional battery concept, but the idea stuck with Chiang, who decided to explore it with other metals and landed on the idea of a sodium-based fuel cell.  In this fuel cell format, the device takes in chemicals and runs reactions that generate electricity, after which the products get removed. Then fresh fuel is put in to run the whole thing again—no electrical charging required. (You might recognize this concept from hydrogen fuel cell vehicles, like the Toyota Mirai.) Chiang and his colleagues set out to build a fuel cell that runs on liquid sodium, which could have a much higher energy density than existing commercial technologies, so it would be small and light enough to be used for things like regional airplanes or short-distance shipping. Sodium metal could be used to power regional planes or short distance shipping.GRETCHEN ERTL/MITTR The research team built small test cells to try out the concept and ran them to show that they could use the sodium-metal-based system to generate electricity. Since sodium becomes liquid at about 98 °C (208 °F), the cells operated at moderate temperatures of between 110 °C and 130 °C (or 230 °F and 266°F), which could be practical for use on planes or ships, Chiang says.  From their work with these experimental devices, the researchers estimated that the energy density was about 1,200 watt-hours per kilogram (Wh/kg). That’s much higher than what commercial lithium-ion batteries can reach today (around 300 Wh/kg). Hydrogen fuel cells can achieve high energy density, but that requires the hydrogen to be stored at high pressures and often ultra-low temperatures. “It’s an interesting cell concept,” says Jürgen Janek, a professor at the Institute of Physical Chemistry at the University of Giessen in Germany, who was not involved in the research. There’s been previous research on sodium-air batteries in the past, Janek says, but using this sort of chemistry in a fuel cell instead is new. “One of the critical issues with this type of cell concept is the safety issue,” Janek says. Sodium metal reacts very strongly with water. (You may have seen videos where blocks of sodium metal get thrown into a lake, to dramatic effect). Asked about this issue, Chiang says the design of the cell ensures that water produced during reactions is continuously removed, so there’s not enough around to fuel harmful reactions. The solid electrolyte, a ceramic material, also helps prevent reactions between water and sodium, Chiang adds.  Another question is what happens to one of the cell’s products, sodium hydroxide. Commonly known as lye, it's an industrial chemical, used in products like liquid drain-cleaning solution. One of the researchers’ suggestions is to dilute the product and release it into the atmosphere or ocean, where it would react with carbon dioxide, capturing it in a stable form and preventing it from contributing to global warming. There are groups pursuing field trials using this exact chemical for ocean-based carbon removal, though some have been met with controversy. The researchers also laid out the potential for a closed system, where the chemical could be collected and sold as a by-product. There are economic factors working in favor of sodium-based systems, though it would take some work to build up the necessary supply chains. Today, sodium metal isn’t produced at very high volumes. However, it can be made from sodium chloride (table salt), which is incredibly cheap. And it was produced more abundantly in the past, since it was used in the process of making leaded gasoline. So there’s a precedent for a larger supply chain, and it’s possible that scaling up production of sodium metal would make it cheap enough to use in fuel cell systems, Chiang says. Chiang has cofounded a company called Propel Aero to commercialize the research. The project received funding from ARPA-E’s Propel-1K program, which aims to develop new forms of high-power energy storage for aircraft, trains, and ships. The next step is to continue research to improve the cells’ performance and energy density, and to start designing small-scale systems. One potential early application is drones. “We’d like to make something fly within the next year,” Chiang says. “If people don’t find it crazy, I’ll be rather disappointed,” Chiang says. “Because if an idea doesn’t sound crazy at the beginning, it probably isn’t as revolutionary as you think. Fortunately, most people think I’m crazy on this one.”

A new type of fuel cell that runs on sodium metal could one day help clean up sectors where it’s difficult to replace fossil fuels, like rail, regional aviation, and short-distance shipping. The device represents a departure from technologies like lithium-based batteries and is more similar conceptually to hydrogen fuel cell systems.  The sodium-air fuel cell was designed by a team led by Yet-Ming Chiang, a professor of materials science and engineering at MIT. It has a higher energy density than lithium-ion batteries and doesn’t require the super-cold temperatures or high pressures that hydrogen does, making it potentially more practical for transport. “I’m interested in sodium metal as an energy carrier of the future,” Chiang says.   The device’s design, published today in Joule, is related to the technology behind one of Chiang’s companies, Form Energy, which is building iron-air batteries for large energy storage installations like those that could help store wind and solar power on the grid. Form’s batteries rely on water, iron, and air. One technical challenge for metal-air batteries has historically been reversibility. A battery’s chemical reactions must be easily reversed so that in one direction they generate electricity, discharging the battery, and in the other electricity goes into the cell and the reverse reactions happen, charging it up. When a battery’s reactions produce a very stable product, it can be difficult to recharge the battery without losing capacity. To get around this problem, the team at Form had discussions about whether their batteries could be refuelable rather than rechargeable, Chiang says. The idea was that rather than reversing the reactions, they could simply run the system in one direction, add more starting material, and repeat.  Ultimately, Form chose a more traditional battery concept, but the idea stuck with Chiang, who decided to explore it with other metals and landed on the idea of a sodium-based fuel cell.  In this fuel cell format, the device takes in chemicals and runs reactions that generate electricity, after which the products get removed. Then fresh fuel is put in to run the whole thing again—no electrical charging required. (You might recognize this concept from hydrogen fuel cell vehicles, like the Toyota Mirai.) Chiang and his colleagues set out to build a fuel cell that runs on liquid sodium, which could have a much higher energy density than existing commercial technologies, so it would be small and light enough to be used for things like regional airplanes or short-distance shipping. Sodium metal could be used to power regional planes or short distance shipping.GRETCHEN ERTL/MITTR The research team built small test cells to try out the concept and ran them to show that they could use the sodium-metal-based system to generate electricity. Since sodium becomes liquid at about 98 °C (208 °F), the cells operated at moderate temperatures of between 110 °C and 130 °C (or 230 °F and 266°F), which could be practical for use on planes or ships, Chiang says.  From their work with these experimental devices, the researchers estimated that the energy density was about 1,200 watt-hours per kilogram (Wh/kg). That’s much higher than what commercial lithium-ion batteries can reach today (around 300 Wh/kg). Hydrogen fuel cells can achieve high energy density, but that requires the hydrogen to be stored at high pressures and often ultra-low temperatures. “It’s an interesting cell concept,” says Jürgen Janek, a professor at the Institute of Physical Chemistry at the University of Giessen in Germany, who was not involved in the research. There’s been previous research on sodium-air batteries in the past, Janek says, but using this sort of chemistry in a fuel cell instead is new. “One of the critical issues with this type of cell concept is the safety issue,” Janek says. Sodium metal reacts very strongly with water. (You may have seen videos where blocks of sodium metal get thrown into a lake, to dramatic effect). Asked about this issue, Chiang says the design of the cell ensures that water produced during reactions is continuously removed, so there’s not enough around to fuel harmful reactions. The solid electrolyte, a ceramic material, also helps prevent reactions between water and sodium, Chiang adds.  Another question is what happens to one of the cell’s products, sodium hydroxide. Commonly known as lye, it’s an industrial chemical, used in products like liquid drain-cleaning solution. One of the researchers’ suggestions is to dilute the product and release it into the atmosphere or ocean, where it would react with carbon dioxide, capturing it in a stable form and preventing it from contributing to global warming. There are groups pursuing field trials using this exact chemical for ocean-based carbon removal, though some have been met with controversy. The researchers also laid out the potential for a closed system, where the chemical could be collected and sold as a by-product. There are economic factors working in favor of sodium-based systems, though it would take some work to build up the necessary supply chains. Today, sodium metal isn’t produced at very high volumes. However, it can be made from sodium chloride (table salt), which is incredibly cheap. And it was produced more abundantly in the past, since it was used in the process of making leaded gasoline. So there’s a precedent for a larger supply chain, and it’s possible that scaling up production of sodium metal would make it cheap enough to use in fuel cell systems, Chiang says. Chiang has cofounded a company called Propel Aero to commercialize the research. The project received funding from ARPA-E’s Propel-1K program, which aims to develop new forms of high-power energy storage for aircraft, trains, and ships. The next step is to continue research to improve the cells’ performance and energy density, and to start designing small-scale systems. One potential early application is drones. “We’d like to make something fly within the next year,” Chiang says. “If people don’t find it crazy, I’ll be rather disappointed,” Chiang says. “Because if an idea doesn’t sound crazy at the beginning, it probably isn’t as revolutionary as you think. Fortunately, most people think I’m crazy on this one.”

Artificial intelligence has sent demand for electricity skyrocketing in the U.S. after years of virtually zero growth. That has sent Big Tech companies scrambling to secure generating capacity for their data centers. For many, that has meant turning to nuclear fission. The power source has been experiencing a resurgence in the last few years following decades of plant closures. (Fission, used in all current nuclear plants, is distinct from fusion, the still-experimental approach to getting power from atoms that, while attracting investors, has yet to produce more electricity than it consumes.) For tech companies, part of the appeal of fission is a stable, predictable source of power that flows 24/7, giving their data centers the potential to run computing loads whenever they require it.  But another part of the appeal lies in new reactor designs that promise to overcome the shortcomings of existing nuclear power plants. Where old power plants were built around massive reactors that could generate over 1 gigawatt of electricity, new small modular reactor (SMR) designs see multiple modules deployed alongside each other to meet a range of needs.  SMRs rely on mass manufacturing to bring costs down, but to date, no one has built one in the U.S. Still, that hasn’t kept Amazon, Google, Meta, and Microsoft away from the table. They’ve either signed agreements to buy power from nuclear startups or invested in them directly — or both. Here are the nuclear fission startups backed by Big Tech. Kairos Power Kairos Power received a vote of confidence from Google when the search giant promised to buy around 500 megawatts of electricity by 2035, with the first reactor targeted to come online by 2030. Techcrunch event Join us at TechCrunch Sessions: AI Secure your spot for our leading AI industry event with speakers from OpenAI, Anthropic, and Cohere. For a limited time, tickets are just $292 for an entire day of expert talks, workshops, and potent networking. Exhibit at TechCrunch Sessions: AI Secure your spot at TC Sessions: AI and show 1,200+ decision-makers what you’ve built — without the big spend. Available through May 9 or while tables last. Berkeley, CA | June 5 REGISTER NOW The company’s small modular reactors rely on molten fluoride salt for cooling and to transport heat to a steam turbine. The salt’s high boiling point means that the coolant doesn’t need to be kept at high pressure, which should improve operating safety. The reactors contain fuel pebbles coated in carbon and ceramic shells, which should be strong enough to withstand a meltdown. The Alameda-based startup has received a $629 million award from the U.S. government, including $303 million from the Department of Energy. In November 2024, Kairos received approval from the U.S. Nuclear Regulatory Commission to commence construction on two reactors in Tennessee. At 35 megawatts, the test units will be smaller than Kairos’ eventual commercial reactors, which are expected to generate 75 megawatts each. Oklo Oklo is another SMR company targeting the data center world — no surprise given that it was backed by OpenAI CEO Sam Altman, who also took the nuclear startup public via a reverse merger with his special purpose acquisition vehicle, AltC, in July 2023. Altman served as chairman of Oklo until April, when he stepped down as OpenAI began negotiating with Oklo for an energy supply agreement. DCVC, Draper Associates, and Peter Thiel’s Mithril Capital Management are among the startup’s previous investors. Cooled by liquid metal, Oklo’s reactor is based on an existing U.S. Department of Energy design that’s intended to reduce the amount of nuclear waste that results from regular operations. Still, Oklo’s path hasn’t been a smooth one. The company’s first license application was denied in January 2022. Oklo has said it will resubmit the application sometime in 2025. But that hasn’t stopped the company from landing a deal to supply data center operator Switch with 12 gigawatts by 2044. Saltfoss Like Kairos, Saltfoss, formerly known as Seaborg, also wants to build SMRs cooled by molten salt. But unlike Kairos and others, it envisions placing two to eight of them on a ship to create what it calls a Power Barge. The startup has raised nearly $60 million, including a $6 million seed round that included investments from Bill Gates, Peter Thiel, and Unity co-founder David Helgason, according to PitchBook. Satlfoss has an agreement with Samsung Heavy Industries to build the ships and the Satlfoss-designed reactors. TerraPower Founded by Bill Gates, TerraPower is building a larger reactor, called Natrium, which is cooled by liquid sodium and features molten salt energy storage. The company broke ground on the first power plant in June 2024 in Wyoming. The Natrium design calls for the reactor to generate 345 megawatts of electricity. That’s smaller than other new nuclear plants today but larger than most SMR designs.  But Natrium has a trick up its sleeve with its molten salt heat storage system. Since nuclear reactors operate best at a steady state, the Natrium reactor can continue breaking atoms when demand is low, and the extra energy is stored as heat in a vat of molten salt, which can be drawn upon later to generate electricity. Investors include Gates’ Cascade Investment fund, Khosla Ventures, CRV, and ArcelorMittal. X-Energy X-Energy landed a hefty $700 million Series C-1 last year led by Amazon’s Climate Pledge Fund. At the same time, the SMR startup announced two development agreements that would see the deployment of 300 megawatts of new nuclear generating capacity in the Pacific Northwest and Virginia. The company’s high-temperature, gas-cooled reactors buck recent trends in the U.S. and Europe, where the design has been shunned in favor of other approaches. The company’s Xe-100 reactor is expected to generate 80 megawatts of electricity. Helium gas flows through the reactor’s 200,000 billiard ball-sized fuel “pebbles,” absorbing heat to spin a steam turbine. 

Iran and the United States prepared for a fifth round of negotiations over Tehran’s rapidly advancing nuclear program Friday in Rome, with enrichment emerging as the key issue.U.S. officials up to President Donald Trump insist Iran cannot continue to enrich uranium at all in any deal that could see sanctions lifted on Tehran’s struggling economy. Iran’s Foreign Minister Abbas Araghchi early Friday insisted online that no enrichment would mean “we do NOT have a deal.” “Figuring out the path to a deal is not rocket science,” Araghchi wrote on the social platform X. “Time to decide.”The U.S. will be again represented in the talks by Mideast envoy Steve Witkoff and Michael Anton, the State Department’s policy planning director. Oman’s Foreign Minister Badr al-Busaidi is mediating the negotiations as the sultanate on the Arabian Peninsula has been a trusted interlocutor by both Tehran and Washington in the talks.A car carrying Araghchi arrived at the Omani Embassy in Rome’s Camilluccia neighborhood around 12:30 p.m. Witkoff had yet to be seen, but the embassy previously served as the site of another round of talks. Enrichment remains key in negotiations The talks seek to limit Iran’s nuclear program in exchange for the lifting of some of the crushing economic sanctions the U.S. has imposed on the Islamic Republic, closing in on half a century of enmity.Trump has repeatedly threatened to unleash airstrikes targeting Iran’s program if a deal isn’t reached. Iranian officials increasingly warn they could pursue a nuclear weapon with their stockpile of uranium enriched to near weapons-grade levels.“Iran almost certainly is not producing nuclear weapons, but Iran has undertaken activities in recent years that better position it to produce them, if it chooses to do so,” a new report from the U.S. Defense Intelligence Agency said. “These actions reduce the time required to produce sufficient weapons-grade uranium for a first nuclear device to probably less than one week.”However, it likely still would take Iran months to make a working bomb, experts say.Enrichment remains the key point of contention. Witkoff at one point suggested Iran could enrich uranium at 3.67%, then later began saying all Iranian enrichment must stop. That position on the American side has hardened over time.Asked about the negotiations, State Department spokesperson Tammy Bruce said “we believe that we are going to succeed” in the talks and on Washington’s push for no enrichment.“The Iranians are at that table, so they also understand what our position is, and they continue to go,” Bruce said Thursday.One idea floated so far that might allow Iran to stop enrichment in the Islamic Republic but maintain a supply of uranium could be a consortium in the Mideast backed by regional countries and the U.S. There also are multiple countries and the International Atomic Energy Agency offering low-enriched uranium that can be used for peaceful purposes by countries.However, Iran’s Foreign Ministry has maintained enrichment must continue within the country’s borders and a similar fuel-swap proposal failed to gain traction in negotiations in 2010.Meanwhile, Israel has threatened to strike Iran’s nuclear facilities on their own if it feels threatened, further complicating tensions in the Mideast already spiked by the Israel-Hamas war in the Gaza Strip.Araghchi warned Thursday that Iran would take “special measures” to defend its nuclear facilities if Israel continues to threaten them, while also warning the U.S. it would view it as being complicit in any Israeli attack. Authorities allowed a group of Iranian students to form a human chain Thursday at its underground enrichment site at Fordo, an area with incredibly tight security built into a mountain to defend against possible airstrikes. Talks come as U.S. pressure on Iran increases Yet despite the tough talk from Iran, the Islamic Republic needs a deal. Its internal politics are inflamed over the mandatory hijab, or headscarf, with women still ignoring the law on the streets of Tehran. Rumors also persist over the government potentially increasing the cost of subsidized gasoline in the country, which has sparked nationwide protests in the past.Iran’s rial currency plunged to over one million to a U.S. dollar in April. The currency has improved with the talks, however, something Tehran hopes will continue as a further collapse in the rial could spark further economic unrest.Meanwhile, its self-described “Axis of Resistance” sits in tatters after Iran’s regional allies in the region have faced repeated attacks by Israel during its war against Hamas in the Gaza Strip. The collapse of Syrian President Bashar Assad’s government during a rebel advance in December also stripped Iran of a key ally.The Trump administration also has continued to levy new sanctions on Iran, including this week, which saw the U.S. specifically target any sale of sodium perchlorate to the Islamic Republic. Iran reportedly received that chemical in shipments from China at its Shahid Rajaei port near Bandar Abbas. A major, unexplained explosion there killed dozens and wounded over 1,000 others in April during one round of the talks. Gambrell reported from Dubai, United Arab Emirates. Associated Press writer Nasser Karimi in Tehran, Iran, contributed to this report. —Jon Gambrell and Giada Zampano, Associated Press

New contact lenses can provide infrared visionolga Yastremska/Alamy Contact lenses have enabled people to see beyond the visible light range, picking up flickers of infrared light even in the dark – or with their eyes closed. The lenses contain engineered nanoparticles that absorb and convert infrared radiation – specifically, a near-infrared wavelength range of 800 to 1600 nanometres – into blue, green and red light visible to the human eye. That is the same trick night-vision devices use to help people see in the dark, but the contact lenses weigh much less and require no additional power. Advertisement “The contact lenses would provide military personnel with discreet, hands-free night-vision capabilities that overcome the limitations of bulky night-vision [goggles or scopes],” says Peter Rentzepis at Texas A&M University, who has done related research applying the same nanoparticles – sodium gadolinium fluoride, ytterbium and erbium – to eyeglass lenses. The new wearables, developed by Yuqian Ma at the University of Science and Technology of China and his colleagues, don’t provide detailed night vision yet. That is because they can pick up only “high-intensity, narrowband LED” light sources, says Rentzepis, rather than lower levels of infrared light from ambient sources. “It’s an audacious paper but, using just the contact lens, you wouldn’t be able to read a book in the infrared, or navigate down a dark road,” says Mikhail Kats at the University of Wisconsin-Madison, who was not involved in the research. Receive a weekly dose of discovery in your inbox. Sign up to newsletter Instead, in tests on humans and mice, the contacts converted a normally invisible flash of infrared light into what Kats says should be a “big colourful blob of visible light”. Those blobs had uses, however. For example, Ma and his colleagues varied the frequency, number and colour of different light flashes to encode and transmit letters of the alphabet. This follows a previous study in which the researchers injected nanoparticles directly into the eyes of mice to provide infrared vision. The wearable contacts represent a “safer and more practical approach for human applications”, says Rentzepis. But they still come with potential health and safety risks, he notes, such as heat exposure from the light-conversion process and possible nanoparticle leakage into eye tissue. Journal referenceCell DOI: 10.1016/j.cell.2025.04.019 Topics:

A new startup claims it can mass-produce "Superwood," a material that's stronger and lighter than steel, with 90 percent lower carbon emissions compared to the widely used alloy.InventWood, the company behind the material, says its new product "has the capacity to substitute up to 80 percent of steel used globally," and "reduce greenhouse gas emissions by over 2 gigatons."According to the firm, its Superwood has up to 50 percent more tensile strength compared to steel, has "minimal expansion and contraction," and a Class A fire rating — all crucial details for architects who might someday use Superwood in their buildings.As TechCrunch reports, the startup has already secured $15 million in a Series A funding round, which its founder, materials scientist Liangbing Hu, says will go toward the company's first factory.The whole thing came about in 2018, when Hu published a landmark research paper detailing how to "transform bulk natural wood directly into a high-performance structural material."It's a relatively simple process that involves boiling wood in a mixture of lye and sodium sulfite — widely available compounds often used as additives in industrial food operations.Lu's paper says the strategy has been found to be "universally effective" for all species of lumber.The research has been used to launch startups like Cambium, a "global tech platform for recycled wood," as Lu worked to refine the process and launch his own commercial venture.But whether Superwood lives up to its founders claims is another story.The materials science industry moves at a snail's pace, thanks to the many factors involved in approving new products for use in buildings. The caution only increases with lumber, which could suffer unforeseen changes due to time, moisture, heat, stress, and transportation, according to the Construction Specifier, a trade publication.Cross-laminated timber (CLT), for example, while used in Europe for decades, has had a tough time catching on in the US, as untested American manufacturers rush their products to market and architects struggle to find construction firms with CLT experience.That's led to incidents like the Peavy Hall collapse at Oregon State University, where a 1,000-pound section of a newly constructed CLT building caved in on a lower floor.Prior to the collapse, manufacturers charmed regulators and project managers with similar promises of their product's strength and environmental impact.At the moment, it seems like InventWood is taking it slow and building out its enterprise selling Superwood as a decorative material, rather than structural beams."Right now, coming out of this first-of-a-kind commercial plant — so it’s a smaller plant — we're focused on skin applications," the company's CEO Alex Lau told TechCrunch, referencing building skins. "Eventually we want to get to the bones of the building."Whether they do will depend on it gaining the confidence of architects and engineers, a process which will require years of patience. As with all startups, it's one thing to build it out on paper — now they have to do it for real.Share This Article

Three compounds in peppers appear to lessen their perceived spiciness. Credit: Deposit Photos / David Kadlec Get the Popular Science daily newsletter💡 Breakthroughs, discoveries, and DIY tips sent every weekday. Hot peppers aren’t for everyone, but that’s where the Scoville scale comes in handy. The scale is named after American pharmacist Wilbur Scoville, who developed the pepper spiciness test in 1912. To determine a rating, an exact amount of dried pepper is dissolved in alcohol to extract its capsaicinoids, the group of compounds responsible for all that heat. This solution is then diluted with sugar water and assessed by a trained panel of specialists. To get a sense of the spectrum, bell peppers rank around a 0 on Scoville Heat Units (SHUs), while notorious hybrids like the Carolina reaper measure as much as 2,500,000 SHUs. But even the Carolina reaper pales in comparison to Pepper X, the Guinness World Record holder for hottest hot pepper, ranking in at a bear spray-like 2,693,000 SHUs. As you may have already worried, even a trained human taste tester can offer subjective assessments, making the Scoville scale more of an approximation than a science. Sometimes a highly rated pepper feels like a dud, or what should be a moderate jalapeno results in gulping down multiple glasses of milk. But even modern methodologies based on high-performance liquid chromatography (HPLC) can rate peppers in ways that confound a sweating hot sauce enthusiast. If the capsaicinoids—particularly capsaicin and dihydrocapsaicin—are tallied accurately, then why the varying perceived heat levels? That’s what a team of researchers recently set out to determine. Their conclusions, published in the American Chemical Society’s Journal of Agricultural and Food Chemistry, identifies a trio of separate compounds that can essentially function as an “anti-spice” weapon. And the ramifications go far beyond the palette. To get to the bottom of the spice mystery, experts at The Ohio State University collected powdered samples from 10 pepper varieties including serrano, Scotch bonnet, and Chile de árbol. They then measured each fruit’s capsaicin and dihydrocapsaicin levels using a process known as liquid chromatography mass spectrometry. A trained group of taste testers next tried each pepper powder after mixing them into tomato juice. Don’t worry—no volunteers were harmed during the experiment. Instead, the concoctions featured just enough of each respective powder to bring the heat up to 800 SHU. That’s around the spice of a Cuban pepper, but less than a poblano. While each sample contained the same levels of capsaicin and dihydrocapsaicin, participants reported a significantly wide range of perceived heat across the 10 peppers. Their hot takes (sorry) implied more than just the capsaicinoids were at play. Researchers then ran multiple more chemical composition analyses including nuclear magnetic resonance imaging to ultimately pinpoint another five naturally occurring compounds suspected of influencing each pepper’s perceived spice level. The team next asked another group of taste testers to judge whether those compounds altered capsaicin and dihydrocapsaicin pungency, either on their own or in combination with one another. Scientists ultimately determined that while three of those compounds—capsianoside I, roseoside, and gingerglycolipid A—reduced intensity, they didn’t do so in combination with one another. Notably, none of them also offered a discernible flavor when mixed into water. According to study corresponding author Devin Peterson, these newly identified compounds can serve as key additives to fine-tune everyday cuisine. “These advancements could enable the customization of desirable spicy flavor profiles or lead to the creation of a household ingredient designed to tone down excessive heat in dishes—the anti-spice,” Peterson said in an accompanying statement. The possibilities extend far beyond the kitchen. Aside from food customization, pharmaceutical designers may soon turn to capsianoside I, roseoside, and gingerglycolipid A while creating new medications and treatments. Peterson suggests “significant medical potential” could come by leveraging these compounds’ ability to reduce perceived discomfort into novel non-opioid analgesic agents for managing pain In the meantime, the new study serves as a good reminder to always take Scoville levels with a grain of salt—not that sodium would help ease unintended pepper pains, of course.

As long as you keep up with regular cleaning and follow the recommended maintenance tips we’ve rounded up here, you shouldn’t have any issues.Is it expensive to maintain quartz countertops?According to Booth, not in the slightest. “Quartz is nonporous,” she says. “So there is no need to routinely seal the surface.” In comparison, countertops such as quartzite, granite, and marble do need to be routinely sealed to maintain their appearance. That being said, you may face some hefty costs if you don’t follow the general recommendations for preventing long-term damage to your countertops, like avoiding extreme heat or scratching them with knives or other sharp objects.Can you use Clorox wipes on quartz countertops?The short answer? Probably not. The long answer? Right this way. Many Clorox wipes are actually bleach-free. You can use them occasionally for deep cleaning, but they shouldn’t be the first thing you grab. You shouldn’t be using Clorox wipes daily, or even often, on quartz countertops because they have citric acid, which can be very harsh on your counter. Long-term use could lead to discoloration of your quartz surface.Can I use Windex on quartz countertops?Windex is considered a base and has a pretty high pH level, which means it could be damaging to quartz. Some professionals say it’s okay to use in small quantities, while others warn against it. For the safest and most sure option to keeping your quartz clean, skip Windex and opt for a mild cleaner like dish soap.In general you should be very careful when using this cleaner. Some Windex formulas rely on the cleaning agent ammonia, which can create very harmful mixtures when combined with bleach—like sodium hypochlorite. This combo can create chloramine vapor, a noxious fume that can irritate your eyes, nose, throat, and airway. In some cases, large quantities can even be fatal.What should you not clean quartz countertops with?In addition to avoiding Clorox and Windex, you shouldn’t use anything with abrasive or harsh chemicals to clean your stone countertops. That means skipping bleach, degreaser, oven cleaner, scouring pads, or other alkaline cleaning solutions or disinfecting formulas with high pH levels. These highly acidic cleaners will damage the countertop and ruin its integrity. If you‘re using them on other items, make sure the spray doesn’t land on the stone surface.To prevent stubborn gunk from building up, it’s best to stick to mild detergents, soapy water and gentle cleaning products. Keep up with a daily maintenance routine rather than trying to address the dirt with a deep cleaning method or harsh cleaners later on. If you happen to have accidents involving nail polish or permanent marker stains, try DIY methods, like using watered-down lemon juice or a dose of rubbing alcohol in a spray bottle.It’s also important to keep quartz surfaces safe from hot pans because they are sensitive to extreme heat. You can use trivets and hot pads to protect granite countertops (which have quartz) from off-the-stove dishes. For food prep that uses sharp objects, especially knives for chopping, cutting boards protect the surface from scratches and divots. And it’s always best to keep coasters around for hot mugs.How to remove stubborn stains from quartz countertopsTo prevent stubborn gunk from building up on quartz countertops, it’s best to stick to mild detergents, soapy water, and gentle cleaning products. Keep up with a daily maintenance routine rather than trying to go back in with a deep cleaning method or harsh cleaners later on. As a general rule of thumb for any stains you come across, Booth recommends first trying mild cleaning solutions before reaching for the stronger, harsher options; it’s better to start slow than risk causing irreversible damage. “I suggest starting with mild dish soap and a microfiber cloth,” she says. “Rub the stain in circular motion and then rinse with clean water.”