Category: 7. Science

ISS astronauts serve up space sushi photo of the day for Sept. 2, 2025

In the microgravity environment aboard the International Space Station (ISS), even simple meals require meticulous preparation: foods are vacuum-sealed, utensils are magnetic and spoons or forks are tethered down to prevent them from floating away.

Despite these constraints, astronauts on the ISS use their creativity to prepare some familiar and favorite dishes, making them feel more at home.

What is it?

Recently, the crew aboard the ISS made space sushi using everyday station ingredients: rice, spam, fish, crackers and condiments. One plate included shrimp with wheat crackers, which was held down on the plate thanks to the weight of the condiments.

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The other plate included sushi with seaweed, rice, tuna and spam that adhered to the plate thanks to its moisture creating surface tension, according to NASA. Both plates were attached to the table using Velcro strips.

Where is it?

The space sushi was served inside the galley of the International Space Station’s Unity module.

Plates of seafood and sushi are served for dinner aboard the ISS. (Image credit: NASA)

Why is it amazing?

Space sushi has been a popular choice aboard the ISS for more than a decade. In February 2010, Japanese astronaut Soichi Noguchi brought raw seafood and shared with his crewmates, introducing the cuisine into orbit. In the isolating and highly regimented life aboard the ISS, a shared meal-making experience can help boost morale, foster community and remind crews of home.

Want to learn more?

You can read more about food on the ISS and cultural cuisines in space.

Breaking space news, the latest updates on rocket launches, skywatching events and more!

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September 2, 2025
NASA advances lunar nuclear plan with commercial focus

WASHINGTON — NASA is moving ahead with plans to support development of a lunar nuclear power system with an emphasis on commercialization.

On Aug. 29, the agency released a draft Announcement for Partnership Proposals, or AFPP, for its Fission Surface Power initiative to gather industry input for the final version.

The AFPP is designed to implement a policy directive signed July 31 by Acting Administrator Sean Duffy that seeks to accelerate work on nuclear power systems for the moon. The directive calls for a reactor capable of producing at least 100 kilowatts of power that would be ready for launch by the end of 2029.

NASA plans to pursue the effort through public-private partnerships using funded Space Act Agreements. While the directive called for selecting two companies, the draft AFPP states NASA can choose “one, multiple or none” of the proposals.

The draft provides few new details about NASA’s requirements. One, restated from the directive, is that the system use a closed Brayton cycle power conversion system — a signal, industry officials said, that NASA wants the technology to scale to higher-power systems.

The reactor would operate in the lunar south polar region for at least 10 years. A cover letter accompanying the draft seeks input on issues including cybersecurity, physical security and reactor fuel.

Under the Space Act Agreement structure, the company would own the reactor and sell power to NASA and other customers. The AFPP requires proposers to submit a financing plan “showing how cash from operations, financing, and NASA covers the expenses of the total end-to-end deployment of the FSP system.”

Proposers must also provide a “Commercial Lunar Power Business Plan” outlining the strategy, potential customers and market size. “The market should include or leverage customers other than NASA,” the draft states.

That approach also extends to delivery. Companies may propose that NASA land the reactor on the moon, if it weighs no more than 15,000 kilograms. But the AFPP says companies “that propose a wholly commercial approach to the end-to-end deployment, all other things being equal, will receive higher-rated proposal evaluations.”

The draft does not state how much funding NASA expects to provide but says the final version, due no later than Oct. 3, will include that information. Awards are expected by March 2026.

The directive followed a report commissioned by the Idaho National Laboratory that recommended accelerating space nuclear power development. One option in that report called for building a reactor of at least 100 kilowatts through traditional contracts; another proposed public-private partnerships for reactors of 10 to 100 kilowatts.

NASA’s blended approach is a “risky combination,” said Bhavya Lal, a former NASA associate administrator for technology, policy and strategy and a co-author of the report, in a SpaceNews webinar Aug. 28.

“It means doing a whole lot of first-of-its-kind things at once,” she said, from reactor design to a launch authorization process that has never been used.

What is helping the initiative, she said, is “a new sense of strategic urgency,” citing Chinese and Russian proposals for a megawatt-class lunar reactor. “This urgency is what finally makes space nuclear real because it turns what used to be a discretionary technology into a strategic imperative.”

“For me,” she said, “success is a commercial space nuclear sector that endures.”

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September 2, 2025
A new telescope design could be key in finding Earth-like planets

image: ©JuSun | iStock

A proposal for new telescope design from astrophysicist Professor Heidi Newberg at Rensselaer Polytechnic Institute could change the way astronomers search for habitable, Earth-like planets

Professor Newberg’s team’s latest research, published in Frontiers in Astronomy and Space Sciences, suggests that replacing the traditional circular telescope mirror with a long rectangular one could make it far easier to detect Earth-like planets orbiting nearby stars.

Life beyond Earth

Earth is the only known planet to support life, as its conditions make life possible, especially the presence of water; however, these conditions could exist on other worlds. Scientists believe that the sun, like stars, is the best target for finding habitable planets, as it offers the right balance of stability and longevity for life to evolve.

Out of the hundreds of billions of stars in our galaxy, only about 60 sun-like stars lie within 30 light-years of Earth. These are the perfect candidates in the search for potentially habitable exoplanets.

Imaging challenges: Changing and improving telescope designs

Detecting an Earth-like planet near one of these stars is difficult. Even under ideal conditions, the Earth is about a million times dimmer than the star it orbits. Without extremely high-resolution imaging, the two objects blur into a single point of light, making it impossible to detect the planet directly.

Telescopes need to collect light over a considerable distance, at least 20 meters, at infrared wavelengths to separate such closely spaced objects in space. Infrared light is key because Earth-like planets emit most of their detectable energy at these wavelengths, particularly around 10 microns. Unfortunately, no current space telescope, including the James Webb Space Telescope (JWST), comes close to this capability. JWST’s mirror is only 6.5 meters wide.

Current alternative options

Some scientists have proposed using formations of multiple small telescopes that work together like a much larger one. Others have considered using a “starshade” to block the light from a star so the planet can be seen more easily. However, these approaches require either ultra-precise positioning or the deployment of multiple spacecraft, both of which are beyond the reach of current technology.

Newberg’s team offers a more practical solution. Instead of a large circular mirror, they suggest a rectangular one measuring one by 20 meters. This shape would provide the telescope with the necessary resolution in one direction to distinguish planets from their host stars. By rotating the mirror to align with the direction of the planet-star separation, astronomers could scan the entire sky for nearby Earth-like planets.

This design could detect about half of all Earth-sized planets orbiting sun-like stars within 30 light-years, and this in under three years. It also avoids the major technical hurdles of the other proposals. The telescope would still need to be in space to prevent image distortion from Earth’s atmosphere, but the rectangular mirror would be much easier to launch than a giant circular one.

Creating another Earth?

If the design performs as expected, scientists could quickly identify dozens of promising planets. These worlds could then be studied for signs of life, such as oxygen-rich atmospheres produced by photosynthesis. In the long term, the most promising candidates could even be visited by robotic probes.

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September 2, 2025
We still haven’t documented 90 percent of animals on Earth

It’s easy to assume, as many people do, that our planet is well explored. In the last few centuries, humans have summited Earth’s highest peaks, dived its deepest ocean trenches, and trekked to the North and South poles, documenting the diversity of life along the way — the many birds, butterflies, fish, and other creatures with which we share our big planet.

Life on Earth is now largely known.

The more that scientists study the planet’s biodiversity, the more they realize how little of it we know. They estimate that for every species we’ve discovered, there are likely at least another nine or so that remain undiscovered or unidentified, meaning around 90 percent of life on Earth is unknown.

This doesn’t include the big stuff — the black bears and belugas and bald eagles, all of which have scientific names and descriptions published in academic journals. The unknown is made up of small organisms, such as insects, mites, and crustaceans. These species are the nuts and bolts of ecosystems: They produce soil, pollinate crops, and feed almost everything. And most of them have yet to be identified.

In just one fly family known as Cecidomyiidae, for example, scientists estimate there could be as many as 1.8 million species globally, and yet fewer than 7,000 have been described. This is especially remarkable given that the total number of described species across the entire animal kingdom is somewhere around 2 million.

Biologists describe animals like this as dark taxa, a term that refers to groups of organisms in which the bulk of species are undescribed or undiscovered. Some taxonomists have also called them biology’s dark matter.

“Most people think that life on Earth is described, and we have a good idea of how ecosystems are functioning,” said Emily Hartop, a fly researcher and taxonomist at the Norwegian University of Science and Technology, who studies dark taxa. “The reality is that for most species on Earth, we don’t know what they are, we don’t know where they are, we don’t know what they’re doing. They are unknown.”

Center for Biodiversity Genomics, University of Guelph

Center for Biodiversity Genomics, University of Guelph

Center for Biodiversity Genomics, University of Guelph

Center for Biodiversity Genomics, University of Guelph

Scientists who study dark taxa argue that lifting the shadow on these organisms is essential to our own survival. If we don’t know what constitutes our ecosystems, we risk killing off the key players that make them function — or failing to detect a potential threat, such as a disease-carrying insect that could set off the next global pandemic.

“The little things run the planet,” said Rudolf Meier, a researcher at Berlin’s Museum of Natural History and Humboldt University of Berlin who also studies dark taxa.

Hartop and some other researchers have dedicated their careers to exposing dark taxa — to making Earth’s unknown known. But filling these gaps is an enormous task and, until recently, considered impossible. The challenge comes down to process: How do you identify millions upon millions of species that are tiny, often look the same, and lack the traditional sort of charisma that funds expeditions?

Dark taxa biologists find hundreds of new species wherever they look

A little over a decade ago, when Hartop was living in Los Angeles, she and her colleagues set up bug traps in backyards across the city. They were mesh tents with openings, known as Malaise traps. Once flies buzz into them, they get stuck and navigate — rather unfortunately for them — into a vial of ethanol. The ethanol both kills and preserves the animals.

Over the course of just one year, the traps collected 99 species of scuttle flies, small insects in the family Phoridae that look, to my untrained eyes, a lot like fruit flies. Forty-three of those species were new to science and had never been described before.

When scientists look for dark taxa, they seem to find new species everywhere. Meier and his colleagues recently collected fungus gnats in Singapore, and their traps revealed 120 species. All but four or five were unknown to science. When researchers went looking for wasps in Costa Rica that parasitize other insects, they found 416 species. More than 400 of them hadn’t been described yet.

And the opportunity for discovery extends beyond the animal world. Scientists recently analyzed genetic codes from thousands of specimens of ectomycorrhizal fungi — a type of fungi that form symbiotic relationships with plant roots — and found that only around 20 percent of those codes matched known species.

Why have these organisms been overlooked for so long? One reason is that they’re typically small, often measuring less than 5 millimeters, Meier said. That makes them harder to notice — and less exciting by traditional standards.

“Funders are much more likely to give you money for birds and butterflies, because that’s something that a funder, who is not a biologist, finds much more relatable,” Meier told me. “If I want to get money for doing things on dark taxa, I first have to override these biases.”

But a far bigger obstacle is that these groups of life are extremely diverse. There are three species of elephants and eight species of bear. Meanwhile, there could be 1 million species of scuttle flies globally, Hartop said.

That creates a problem of scale. While trapping bugs in tents is easy, it’s much harder to identify them and demonstrate that they’re different from other species that have already been described. Until recently, it was nearly impossible.

We are in the Golden Age of discovery

For hundreds of years, scientists have largely categorized animals by their appearance. A toucan is obviously different from a robin, which is obviously different from a hummingbird. Scientists use these distinctions in form to separate animals by species, typically defined as organisms that reproduce with each other but not with other animal groups.

The study of form, known as morphology, has been used to categorize small things, too, such as moths and butterflies. But for some animal groups — scuttle flies, mites, and nematodes, for example — this approach is inadequate. While distinguishing these animals by appearance is often possible, it typically requires an enormous amount of time and expertise; scientists literally have to look at them one by one through a microscope. Plus, looks can be deceiving: A bunch of, say, black-and-blue butterflies might appear identical but come from different genetic lineages that make them distinct species.

That’s why a technology called DNA sequencing has been such a game-changer. In the 1970s, scientists figured out how to sequence part of an organism’s DNA, producing a string of letters that corresponds to its genes. They later discovered that they could use just a small snippet of that sequence to tell one species apart from another. In 2003, a Canadian biologist named Paul Hebert dubbed those snippets “barcodes” because they serve as unique species IDs, akin to barcodes on cereal boxes in the grocery store.

Over time, scientists sequenced animals and uploaded their barcodes to databases, helping organize and reorganize the animal kingdom. All the while, the technology evolved. DNA sequencing is now so advanced that taxonomists — those who classify life — can barcode thousands of specimens at one time.

It’s this approach that’s helping illuminate dark taxa: Researchers can collect scores of specimens from the field, sequence portions of their DNA, and then upload those bits of code to an existing database to see if they match known species. If not, they might represent something new.

Even with modern DNA sequencing, identifying unknown life is, to be clear, still very hard. A big issue is that there aren’t barcodes for most species that scientists have already described. Museums might have physical specimens — dead moths or beetles in a drawer in their basement — that lack genetic data in online databases. So just sequencing a discovery is usually not enough to prove that something is new to science.

When scientists are confident that they’ve found something new, they’ll face additional challenges if they want to formally describe the animal and give it a scientific name. That typically requires multiple lines of evidence and a description published in a scientific journal. Doing that for dark taxa — which, again, have hundreds of thousands of unknown species — would be incredibly time-consuming. (The world of taxonomy is full of drama about the species-naming process and how much evidence scientists should be required to provide. There’s also a debate about whether formally naming species actually matters if they already have unique DNA sequences that identify them.)

Nonetheless, modern DNA sequencing has massively sped up the process for discovering and identifying life. It’s pretty extraordinary: Even though we’ve known about the most visible species around us for hundreds of years, only now are we in the Golden Age of species discovery.

“It’s unbelievable,” said Hebert, a professor at the University of Guelph in Ontario who oversees the Center for Biodiversity Genomics, a DNA-barcoding research center. “This is the age of bio-discovery.”

Can we describe all life on Earth?

That’s the goal. While there are no reliable estimates for the total number of species on Earth, it’s likely in the tens of millions. And again, only around 2 million are formally described, Hebert said.

Before modern sequencing became a reality, identifying all life on Earth would have taken hundreds, if not thousands, of years and likely would have cost trillions of dollars. Now, some scientists are confident that they can do it in a matter of decades or even years.

In 2005, Hebert launched a project with his colleague Sujeevan Ratnasingham that is essentially trying to collect DNA data for every animal on Earth. So far, the project — known as Barcode of Life — has sequences for roughly 1.5 million species, Hebert said, though many of those are not formally described. To barcode the rest would require no more than $1 billion, he told me confidently. That money would help fund expeditions and DNA sequencing around the world.

“We want barcode records for every species,” Hebert said. “If I can persuade the world to support this with about $1 billion, which is trivial, we can complete the inventory of animal life by 2040 — I am certain.”

Hebert and other taxonomists imagine a world in which all species are known and can thus be tracked. Just as we monitor the weather for looming disasters, complete inventories of animal life could allow scientists to monitor biodiversity — both the obvious and obscure stuff — to see how our ecosystems are changing and what that means for us. Are ocean food chains we rely on shrinking? Are the insect larvae that make our soils fertile in decline? Is a pathogen on the loose?

But there’s also a more noble reason to discover life, he says. “This is the planet we live on,” Hebert said. “We really should understand the organisms that we share it with.”

And if you’ve got a billion dollars lying around, you can apparently help.

“For a billionaire, it’s a no-brainer,” Hebert said. “That’s a legacy for that person. You only get to do it once: discover life on our planet.”

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September 2, 2025
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September 2, 2025
Carving out space for peace – in space – Peace Research Institute Oslo (PRIO)
American astronaut Tom Stafford shaking hands with Soviet cosmonaut Alexei Leonov in the tunnel connecting the Apollo and Soyuz spacecraft. Photo: NASA

Fifty years ago, two spacecraft met in space as part of a unique mission: After nearly two decades of intense space rivalry, the Soviet Union and the USA joined forces. We have much to learn from that landmark event today.

Space – and not least the moon, our natural satellite – became the site of one of the fiercest political and scientific battles of the Cold War. It started in 1957, when the Soviet Union terrified America and the west by the successful launch of Sputnik into Earth orbit.

In the years that followed, the Soviets achieved one success after the other, partly due to an almost extreme willingness to take risks, and partly thanks to the brilliant Ukrainian rocket engineer Sergei Korolev and a corps of brilliant cosmonauts – the Russian name for what in the west became known as astronauts. The Soviets sent up the dog Laika as the first earthly being in space, Yuri Gagarin as the first human in space, and Alexei Leonov as the first human to conduct a spacewalk.

For long, the Americans were lagging seriously behind. But then, Korolev died in 1966 – caused in part by the effects of torture he had been subjected to under the Stalin regime – and the Soviets, highly competent as they were, increasingly had to pay for a combination of hubris, an inefficient system, and the loss of their strong scientific leader.

Throughout this race, the two superpowers were technologically isolated from each other. Nevertheless, they found strikingly similar and often incredibly inventive solutions to the vast technological challenges.

No place for human beings

The challenges were indeed of enormous proportions: Outer space, outside the atmosphere of the Earth, with no air, deadly radiation, and minimal gravity, is no place for humans. When the Soviets initiated their space missions and the Americans soon followed, little was known about what they would encounter.

When John F. Kennedy articulated his ambition in 1961 to place a human on the surface of the moon by the end of the 1960s (and, importantly, to get that same person safely back!), NASA had no more than 15 minutes of experience with manned spaceflight. Whether it was even possible to survive a trip to the moon, land there, and then return to Earth was entirely unknown.

The fact that they eventually succeeded in sending humans to the moon and back is something of a human miracle, driven by brilliant engineering, hundreds of thousands of skilled helpers, and some very brave astronauts.

But above all, it was driven by politics. Hostility and suspicion ran deep between two rival political systems, and both wanted to show that they could achieve what the other could not.

Another way of thinking

Kennedy himself laid the groundwork for a very different and less competitive way of thinking about outer space. In a speech to the UN General Assembly in September 1963, shortly before his death, he urged the Soviet Union to join the USA – along with the world’s United Nations – in a common exploration of outer space and the moon.

This grand vision largely disappeared with Kennedy, and a complex global situation, not least marked by the Vietnam War, made real and extensive space cooperation increasingly less relevant.

Nevertheless, the USA and the Soviet Union managed to come together on the UN Outer Space Treaty of 1967, a confirmation of the idea of cooperation and peace in outer space, even at a time when actual collaboration seemed to be far away.

Apollo and Soyuz

And then it happened: After the USA successfully had sent humans to the moon in 1969, and the Soviet Union started to claim it had other goals for its space research anyway, forces on both sides of the Iron Curtain managed to agree on a joint space mission.

Starting in 1971, the two countries gradually opened their space centers to each other, and technology sharing went hand in hand with the development of strong personal friendships.

Plans were soon formed for a unique physical meeting in outer space between two systems, two languages, and two technologies.
On Thursday, July 17, 1975, an Apollo and a Soyuz capsule docked in orbit around the Earth. Two officers from each side of an intense Cold War shook hands in what has become known as “the handshake of peace”: Alexei Leonov and Tom Stafford and their two crews conducted a series of scientific experiments together, but most importantly: they showed what can be gained both materially, politically, and morally from joining forces.

A few weeks later – unrelated to the mission, but part of the same strong desire and movement for détente – the Helsinki Declaration on Security and Cooperation in Europe was signed.

Today – and back then

Much is different today. The 1975 events were characterized by a post-war generation on both sides of the Iron Curtain. They understood the dangers of world war and had been severely frightened by the Cuban Missile Crisis in 1962, which almost developed into nuclear war.

Today, it seems that such a shared understanding of the dangers of war is less pronounced, and the ideological divides are less clear and much less predictable.

However, the idea behind the Apollo-Soyuz project is at least as valid today – and it should inspire us. Despite conflict and suspicion, it is possible to create space for peaceful cooperation, and it is even possible to lay the groundwork for such cooperation while conflict persists. Women and men in science can learn from each other and find common solutions. We have spoken with many NASA astronauts who emphasize the same, based on years of experience: We must collaborate!

Imagine if today’s most powerful nations could share openly their best knowledge on issues like climate change and biodiversity loss with each other and use each other’s expertise for a joint effort, just as they did with space research 50 years ago and to some extent still do today.

Apollo-Soyuz was not only a scientific success that laid the groundwork for what many years later became collaboration on the Mir and ISS space stations. The mission not least demonstrated that we can create space for peace and respect alongside conflict, without compromising our deepest principles. The road to getting there is long today, partly due to the deep-seated suspicions that exist between China and the west. But we must not imagine that building scientific and diplomatic peace in space is impossible.

Solar eclipse and cooperation

On Saturday, July 19, 1975, the two spacecraft separated, and shortly thereafter, the round Apollo capsule positioned itself between the sun and the Soyuz vehicle, creating an artificial solar eclipse. The Soviets were able to conduct unique solar research for all of humanity, thanks to high-tech cooperation between friends – and enemies.

Fifty years later, we need the spirit of Apollo-Soyuz more than ever.
- Henrik Syse is a Research Professor at PRIO and co-author of Fordi det er vanskelig. Om menneskets utrolige reise til månen [Because it is difficult. On the incredible human voyage to the Moon], published by Cappelen Damm
- Jenny Helene Syse is a student and co-author of Fordi det er vanskelig. Om menneskets utrolige reise til månen [Because it is difficult. On the incredible human voyage to the Moon]
- An earlier version of this text was published in Norwegian by Vårt land 17 July 2025
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September 2, 2025
Can Ice Really Generate Power? Scientists Say Yes
We all know ice is cold, slippery, and great in lemonade. But here’s a twist: it’s also full of surprises.

Even though water molecules are polar (they have tiny electrical charges), frozen water, your everyday ice cube, is non-polar. That means it can’t generate electricity when squeezed or pressed. No sparks, no buzz.

But wait, a new research in Nature Physics just flipped the script. Scientists discovered that ordinary ice is flexoelectric. If you bend or deform it, it can produce electricity.

This discovery, at the UAB campus, Xi’an Jiaotong University (Xi’an), and Stony Brook University (New York), could have significant implications for the development of future technological devices and help to explain natural phenomena such as the formation of lightning in thunderstorms. It also represents an important step forward in our understanding of the electromechanical properties of ice.

Dr Xin Wen, a member of the ICN2 Oxide Nanophysics Group and one of the study’s lead researchers, said, “We discovered that ice generates electric charge in response to mechanical stress at all temperatures. In addition, we identified a thin ‘ferroelectric’ layer at the surface at temperatures below -113ºC (160K). This means that the ice surface can develop a natural electric polarization, which can be reversed when an external electric field is applied, similar to how the poles of a magnet can be flipped.”

“The surface ferroelectricity is a cool discovery in its own right, as it means that ice may have not just one way to generate electricity but two: ferroelectricity at very low temperatures, and flexoelectricity at higher temperatures, all the way to 0 °C.”

This property causes ice to behave like titanium dioxide, a material used in high-tech gadgets such as sensors and capacitors. But here’s the twist: this icy superpower might also help explain how lightning crackles through stormy skies. Nature meets nanotechnology most innovatively.

We know that lightning occurs when electric charge forms in storm clouds, due to ice particles colliding with each other. These icy collisions generate charge, which eventually explodes as a lightning bolt.

But here’s the mystery: ice isn’t piezoelectric, so squishing it doesn’t make electricity. For years, scientists had been unable to explain how those icy bumps led to sparks. The secret might lie not in the squeeze, but in the bend.

To test ice’s flexoelectricity, researchers placed a block of ice between two metal plates and hooked it up to a measuring device. When they bent the ice, it generated electric signals, just like what’s seen when ice particles collide in thunderstorms.

The results of the study suggest that the flexoelectric spark could help explain how clouds get electrified during thunderstorms and how lightning is formed.

Researchers are now exploring how this frosty phenomenon could be harnessed for real-world tech. Imagine electronic devices made from ice itself, designed to operate in freezing environments such as polar regions or icy moons.

It’s early days, but this discovery could turn ice from a passive chill into an active ingredient in future innovations.

Journal Reference:
1. Wen, X., Ma, Q., Mannino, A. et al. Flexoelectricity and surface ferroelectricity of water ice. Nat. Phys. (2025). DOI: 10.1038/s41567-025-02995-6
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September 2, 2025
Chromosome-level genome assembly of the Tyrrhenian tree frog (Hyla sarda)
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