Category: 7. Science

For years, NASA has monitored a strange anomaly in Earth’s magnetic field: a giant region of lower magnetic intensity in the skies above the planet, stretching out between South America and southwest Africa.

This vast, developing phenomenon, called the South Atlantic Anomaly, has intrigued and concerned scientists for years, and perhaps none more so than NASA researchers.

The space agency’s satellites and spacecraft are particularly vulnerable to the weakened magnetic field strength within the anomaly, and the resulting exposure to charged particles from the Sun.

The South Atlantic Anomaly (SAA) – likened by NASA to a ‘dent’ in Earth’s magnetic field, or a kind of ‘pothole in space’ – generally doesn’t affect life on Earth, but the same can’t be said for orbital spacecraft (including the International Space Station), which pass directly through the anomaly as they loop around the planet at low-Earth orbit altitudes.

During these encounters, the reduced magnetic field strength inside the anomaly means technological systems onboard satellites can short-circuit and malfunction if they become struck by high-energy protons emanating from the Sun.

Related: Humanity Has Dammed So Much Water It’s Shifted Earth’s Magnetic Poles

These random hits may usually only produce low-level glitches, but they do carry the risk of causing significant data loss, or even permanent damage to key components – threats obliging satellite operators to routinely shut down spacecraft systems before spacecraft enter the anomaly zone.

Mitigating those hazards in space is one reason NASA is tracking the SAA; another is that the mystery of the anomaly represents a great opportunity to investigate a complex and difficult-to-understand phenomenon, and NASA’s broad resources and research groups are uniquely well-appointed to study the occurrence.

“The magnetic field is actually a superposition of fields from many current sources,” geophysicist Terry Sabaka from NASA’s Goddard Space Flight Centre in Greenbelt, Maryland explained in 2020.

The primary source is considered to be a swirling ocean of molten iron inside Earth’s outer core, thousands of kilometers below the ground. The movement of that mass generates electrical currents that create Earth’s magnetic field, but not necessarily uniformly, it seems.

A huge reservoir of dense rock called the African Large Low Shear Velocity Province, located about 2,900 kilometers (1,800 miles) below the African continent, is thought to disturb the field’s generation, resulting in the dramatic weakening effect – which is aided by the tilt of the planet’s magnetic axis.

“The observed SAA can be also interpreted as a consequence of weakening dominance of the dipole field in the region,” said NASA Goddard geophysicist and mathematician Weijia Kuang in 2020.

“More specifically, a localized field with reversed polarity grows strongly in the SAA region, thus making the field intensity very weak, weaker than that of the surrounding regions.”

Satellite data suggesting the SAA is dividing. (Division of Geomagnetism, DTU Space)

While there’s much scientists still don’t fully understand about the anomaly and its implications, new insights are continually shedding light on this strange phenomenon.

For example, one study led by NASA heliophysicist Ashley Greeley in 2016 revealed the SAA slowly drifts around, which was confirmed by subsequent tracking from CubeSats in research published in 2021.

It’s not just moving, however. Even more remarkably, the phenomenon seems to be in the process of splitting in two, with researchers in 2020 discovering that the SAA appeared to be dividing into two distinct cells, each representing a separate center of minimum magnetic intensity within the greater anomaly.

Just what that means for the future of the SAA remains unknown, but in any case, there’s evidence to suggest that the anomaly is not a new appearance.

A study published in July 2020 suggested the phenomenon is not a freak event of recent times, but a recurrent magnetic event that may have affected Earth since as far back as 11 million years ago.

If so, that could signal that the South Atlantic Anomaly is not a trigger or precursor to the entire planet’s magnetic field flipping, which is something that actually happens, if not for hundreds of thousands of years at a time.

A more recent study published in 2024 found the SAA also has an impact on auroras seen on Earth.

Obviously, huge questions remain, but with so much going on with this vast magnetic oddity, it’s good to know the world’s most powerful space agency is watching it as closely as they are.

“Even though the SAA is slow-moving, it is going through some change in morphology, so it’s also important that we keep observing it by having continued missions,” said Sabaka.

“Because that’s what helps us make models and predictions.”

An earlier version of this article was published in August 2020.

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Recent NASA budget uncertainties could make one space agency endeavor up for grabs — defending Earth from incoming space rocks.

That effort, undertaken by NASA for many years, could be given to the U.S. Space Force, which has a much bigger new budget.

In a discovery that feels ripped from the pages of cosmic poetry, astronomers have found a galaxy shaped like the infinity symbol, and nestled at its heart may be something even more extraordinary: a newborn supermassive black hole.

Yale astronomer Pieter van Dokkum and his team stumbled upon this celestial oddity while combing through images from NASA’s James Webb Space Telescope. What they saw was jaw-dropping: two galaxies amid a collision, their swirling stars forming a glowing figure eight. And right in the center, not in either galactic nucleus, but between them, sat a black hole, embedded in a cloud of gas and actively feeding.

“This is as close to a smoking gun as we’re likely ever going to get,” van Dokkum said.

This isn’t just a cool-shaped galaxy. It could rewrite our understanding of how black holes form.

Scientists detected a chirp of a baby black hole

Traditionally, scientists believed that black holes formed from the remnants of dying stars, small “light seeds” that slowly merged over time. But Webb has already spotted massive black holes too early in the universe’s timeline for that theory to hold up.

Enter the ‘heavy seeds’ theory, championed by Yale astrophysicist Priyamvada Natarajan. It suggests black holes can form directly from collapsing gas clouds, skipping the star stage entirely. The Infinity galaxy might be the first real-world example of that process in action.

According to van Dokkum, the two disk galaxies collided, compressing their gas into dense knots. One of those knots may have collapsed into the black hole now visible as a glowing region between the galactic cores. It’s a rare event, but similar conditions were likely common in the early universe.

As the evidence builds, one detail stands out with cosmic clarity: the black hole isn’t situated within the core of either galaxy. Instead, it occupies a curious position between them, a gravitational outsider lodged at their center. What’s more, it’s not idle.

This black hole is voraciously feeding, pulling in surrounding material and growing larger with each passing moment. Enveloping it is a cloud of ionized gas, signaling the kind of intense compression astronomers associate with high-energy, transformative cosmic events. Altogether, these signs suggest something rare and spectacular.

The team used data not just from Webb but also from the Keck Observatory, Chandra X-ray Observatory, and the Very Large Array to confirm their findings. Still, they say more research is needed to be sure this is truly a black hole being born.

But if it is? We may be witnessing something no one has ever seen before: the birth of a cosmic giant.

Journal References:

1. Pieter van Dokkum, Gabriel Brammer, Josephine F. W. Baggen, Michael A. Keim, Priyamvada Natarajan, Imad Pasha. The Infinity Galaxy: a Candidate Direct-Collapse Supermassive Black Hole Between Two Massive, Ringed Nuclei. The Astrophysical Journal Letters. DOI: 10.48550/arXiv.2506.15618
2. Pieter van Dokkum, Gabriel Brammer, Connor Jennings, Imad Pasha, Josephine F. W. Baggen. Further Evidence for a Direct-Collapse Origin of the Supermassive Black Hole at the Center of the Milky Way. The Astrophysical Journal Letters. DOI: 10.48550/arXiv.2506.15619

The Earth has been spinning unusually fast recently. Last year on July 4, our planet set a record by completing a full spin 1.66 milliseconds (0.00166 seconds) faster than usual, according to timeanddate.com. One year later, on July 10, 2025, Earth completed a daily rotation that scientists estimate was 1.36 milliseconds faster than usual, giving us another particularly short day. Other shorter (but ever-so-slightly longer) days occurred on July 9 and July 22, although the exact margins have yet to be confirmed.

Losing a couple milliseconds may seem insignificant to most of us—perhaps justifiably so. But tiny error margins in time can mess up systems that depend on extremely precise calculations, such as high-speed communication networks, GPS, or banking systems. As such, scientific timekeepers use highly sophisticated atomic clocks to set the standard via the Coordinated Universal Time (UTC). But with the recent acceleration in Earth’s rotation, the need for a “negative” leap second has re-emerged among some timekeeping experts. 

Scientists regularly apply a leap second to keep UTC synchronized with astronomical time, which they base on Earth’s rotation. A full day on Earth—the time it takes our planet to complete one full rotation on its axis—lasts for 86,400 seconds. But factors such as the Sun’s position, the Moon’s orbit, and Earth’s gravitational field influence how quickly the Earth completes its daily cycle. As a result, Earth’s rotation ends up being irregular, and slight differences between UTC and astronomical time can add up in the long run, causing a mismatch between the two.

Leap seconds correct for this deviation. By the same logic, a negative leap second would subtract an extra second from UTC to account for the milliseconds we’re losing from Earth’s faster rotation. Now, this may seem perfectly reasonable, but not all scientists agree. In fact, some scientists found the leap second so problematic that, in 2020, an international group of experts voted to phase out the practice by 2035. 

As computing networks became more globally interconnected, the leap second began to cause “failures and anomalies in computing systems,” Patrizia Tavella, director of the International Bureau of Weights and Measures’ time department, told Live Science in a 2022 interview. Moreover, countries account for leap seconds in different ways, causing major complications for airlines scheduling international flights, she said.

Critics of the proposed negative leap second cite similar concerns. To be clear, no formal institution or body is currently advocating for the negative leap second. But should that happen, squeezing in the negative leap second to our timekeeping system will be difficult given the increasingly interconnected nature of our society, Darryl Veitch, a computer networking expert, explained to Live Science in a recent interview. 

“There are continuing problems with the insertion of positive leap seconds even after 50 years,” Judah Levine, a physicist at the University of Colorado, told Live Science. “And this increases the concerns about the errors and problems of a negative leap second.”

It seems unlikely, therefore, that scientists will actually adopt the negative leap second, especially since they’ve already decided to retire the positive leap second. But given Earth’s recent shorter daily spins, astronomical time might eventually fall behind UTC, forcing the need for negative leap seconds. Levine puts the likelihood of this happening at 30% in the next decade or so, although last year, Duncan Carr Agnew, an oceanographer at the Scripps Institution of Oceanography, argued in a paper from last year that this could occur as early as 2029. However, Veitch also believes our planet might slow down soon, which would be consistent with longer-term trends on record.

But we’ll just have to see—and you can, too! Timekeepers estimate that our next “short” day will fall on August 5.

• New research shows that metasurfaces could be used as strong linear quantum optical networks
• This approach could eliminate the need for waveguides and other conventional optical components
• Graph theory is helpful for designing the functionalities of quantum optical networks into a single metasurface

In the race toward practical quantum computers and networks, photons — fundamental particles of light — hold intriguing possibilities as fast carriers of information at room temperature. Photons are typically controlled and coaxed into quantum states via waveguides on extended microchips, or through bulky devices built from lenses, mirrors, and beam splitters. The photons become entangled – enabling them to encode and process quantum information in parallel – through complex networks of these optical components. But such systems are notoriously difficult to scale up due to the large numbers and imperfections of parts required to do any meaningful computation or networking.

Could all those optical components could be collapsed into a single, flat, ultra-thin array of subwavelength elements that control light in the exact same way, but with far fewer fabricated parts?

Optics researchers in the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) did just that. The research team led by Federico Capasso, the Robert L. Wallace Professor of Applied Physics and Vinton Hayes Senior Research Fellow in Electrical Engineering, created specially designed metasurfaces — flat devices etched with nanoscale light-manipulating patterns — to act as ultra-thin upgrades for quantum-optical chips and setups.

The research was published in Science and funded by the Air Force Office of Scientific Research (AFOSR).

Capasso and his team showed that a metasurface can create complex, entangled states of photons to carry out quantum operations – like those done with larger optical devices with many different components.

“We’re introducing a major technological advantage when it comes to solving the scalability problem,” said graduate student and first author Kerolos M.A. Yousef. “Now we can miniaturize an entire optical setup into a single metasurface that is very stable and robust.”

Metasurfaces: Robust and scalable quantum photonics processors

Their results hint at the possibility of paradigm-shifting optical quantum devices based not on conventional, difficult-to-scale components like waveguides and beam splitters, or even extended optical microchips, but instead on error-resistant metasurfaces that offer a host of advantages: designs that don’t require intricate alignments, robustness to perturbations, cost-effectiveness, simplicity of fabrication, and low optical loss. Broadly speaking, the work embodies metasurface-based quantum optics which, beyond carving a path toward room-temperature quantum computers and networks, could also benefit quantum sensing or offer “lab-on-a-chip” capabilities for fundamental science

Designing a single metasurface that can finely control properties like brightness, phase, and polarization presented unique challenges because of the mathematical complexity that arises once the number of photons and therefore the number of qubits begins to increase. Every additional photon introduces many new interference pathways, which in a conventional setup would require a rapidly growing number of beam splitters and output ports.

Graph theory for metasurface design

To bring order to the complexity, the researchers leaned on a branch of mathematics called graph theory, which uses points and lines to represent connections and relationships. By representing entangled photon states as many connected lines and points, they were able to visually determine how photons interfere with each other, and to predict their effects in experiments. Graph theory is also used in certain types of quantum computing and quantum error correction but is not typically considered in the context of metasurfaces, including their design and operation.

The resulting paper was a collaboration with the lab of Marko Loncar, whose team specializes in quantum optics and integrated photonics and provided needed expertise and equipment.

“I’m excited about this approach, because it could efficiently scale optical quantum computers and networks — which has long been their biggest challenge compared to other platforms like superconductors or atoms,” said research scientist Neal Sinclair. “It also offers fresh insight into the understanding, design, and application of metasurfaces, especially for generating and controlling quantum light. With the graph approach, in a way, metasurface design and the optical quantum state become two sides of the same coin.”

The research received support from federal sources including the AFOSR under award No. FA9550-21-1-0312. The work was performed at the Harvard University Center for Nanoscale Systems

Imagine you’re watching a balloon inflate, but instead of slowing down as it gets bigger, it keeps expanding faster and faster. That’s essentially what scientists discovered about our universe in 1998 using exploding stars called supernovae. They found that some unknown force, which was subsequently named “dark energy” was pushing space itself apart at an accelerating rate. Now, after analyzing over 2,000 of these stellar explosions, researchers have found hints that dark energy might not be as constant as we thought. It may actually be changing, and possibly weakening over time.

A supernova was captured in the Pinwheel Galaxy in 2011 and named SN2011fe (Credit : Thunderf00t)

Type Ia supernovae are incredibly bright explosions that occur when a specific type of dead star, called a white dwarf, accumulates too much material and explodes. They’re so bright that they can be seen across billions of light years, and crucially, they all shine with roughly the same brightness.

This predictability of the brightness makes them perfect “standard candles” for measuring distances in space. Just like you could estimate how far away a streetlight is based on how bright it appears, astronomers can calculate how far these supernovae are from Earth. But here’s the key, by also measuring how much the light from these explosions has been stretched or redshifted by the expansion of space, it’s possible to figure out how fast the universe was expanding at different times in the past.

Since that Nobel Prize winning discovery in 1998, astronomers have spotted more than 2,000 Type Ia supernovae using different telescopes and techniques. But there was a problem, comparing data from different sources was like trying to compare measurements taken with different rulers. Each telescope and survey had its own calibrations and differences.

Schematic of the Type 1a supernova process (Credit : NASA, ESA and A. Feild (STScI))

To solve this, an international team called the Supernova Cosmology Project spent years creating something called “Union3”, the largest standardised dataset of supernovae ever assembled. They painstakingly analysed 2,087 supernovae from 24 different datasets, adjusting for all the differences between telescopes and surveys to put everything on the same scale. When the team analysed this massive, standardised dataset using statistical methods, they found something intriguing. The data suggests that dark energy might not have stayed constant throughout history.

“Dark energy makes up almost 70% of the universe and is what drives the expansion, so if it is getting weaker, we would expect to see expansion slow over time” – David Rubin, the study’s lead author from the University of Hawaii.

This potential change in dark energy has huge implications for the ultimate fate of our universe. Currently, researchers work with a model called Lambda CDM, where dark energy (Lambda) stays constant over time and counteracts the gravitational pull of matter (cold dark matter, or CDM). But if dark energy is actually weakening then the model could play out very differently. If dark energy wins over gravity, the universe continues expanding forever, potentially leading to a “Big Rip” where space expands so fast that even atoms get torn apart. If gravity wins, the expansion could slow down, stop, or even reverse into a “Big Crunch” where everything collapses back together. If they balance, the universe might reach a steady state.

What makes this discovery particularly exciting is that it’s not coming from just one source. A separate study called the Dark Energy Spectroscopic Instrument (DESI), which studies how galaxies cluster together, is seeing similar hints that dark energy might be evolving.

The researchers aren’t ready to definitively declare that dark energy is changing—the evidence, while intriguing, isn’t quite strong enough yet. Over the next year, they plan to add several hundred more supernovae to their dataset, which should provide even more precise measurements. Looking further ahead, new telescopes like the Vera C. Rubin Observatory and the Nancy Grace Roman Space Telescope are expected to discover tens of thousands of additional supernovae over the coming decade.

Source : Largest supernova dataset hints dark energy may be changing over time

Recreating the environment that most spacecraft experience on their missions is difficult on Earth. Many times it involves large vacuum chambers or wind tunnels that are specially designed for certain kinds of tests. But sometimes, engineers get to just do larger scale versions of the things they got to do in high school. That is the case for a recent test of ExoMars’s parachute system. A team of ESA engineers and their contractors performed a scaled up egg-drop test common in physics classes across the world. Except this one involved a stratospheric balloon the size of a football field and a helicopter.

ExoMars has a multi-stage descent system. First, the spacecraft itself will aerobrake through Mars’ atmosphere. Then it will deploy a parachute to slow down even more using just the planet’s atmosphere. A final stage will see the spacecraft deploy retrorockets to perform a soft landing on the surface of the Red Planet.

Each of those sub-systems must be tested in turn, with each requiring different test setups. Recently the mission’s engineers completed testing of the parachute that involved dropping it from the stratosphere to an isolated part of northern Sweden. To get it to the stratosphere, the entire test rig, which represented the heat shield and mock internal components to be used on ExoMars itself, was attached to a giant balloon that, when inflated to its full size, was about the size of a football field.

Video describing the full stratospheric deployment test. Credit – ESA YouTube Channel

After it made it to the stratosphere, the craft was released and immediately deployed its parachute. That high in the atmosphere, the conditions are similar to Mars’ extremely thin atmosphere, and after falling for a certain amount of time, the spacecraft would be going about the same speed it is expected to after the aerobraking stage of its descent. In other words, this test was designed under conditions expected to be found when ExoMars actually gets to Mars.

Sensors onboard the spacecraft captured as much data as possible – orientation, rotation, speed, and even a video camera were all operational on the way down. Once it did land in the northern part of Sweden, a few lunch team members got to take a ride in a helicopter to go find it – which is the dream of most future engineers doing the egg drop test in their physics class in school.

The parachute itself had sat in storage for years before being deployed in this test, so part of the reason for the test itself was to ensure the parachute didn’t degrade over time, even though it was stored in a controlled environment. Despite no publicly released records on whether or nor the test was successful, from a video describing the process and capturing some of the important moments, it certainly seems like it was. At least the parachute itself seemed to deploy and remain intact, and the test vehicle didn’t end up as a smoldering hole in the ground at the end of the test. Most of those high school engineers would count that as a success.

ESA video that describes the process of how ExoMars will get to the surface of the Red Planet. Credit – ESA YouTube Channel

ExoMars itself is planned for launch in October 2028, during one of the bi-yearly openings for Mars launches. So the engineers have about three more years to complete the construction and testing of the rest of their systems. Given the geopolitical tensions surrounding this project, the fact that it is moving foward at all is a small bureacatic miracle. But with this test chalked up as a success, the team can more on to more interesting ones – like potentially blasting the heat shield with a flamethrower or having the spacecraft itself fire its own rockets and land securely on the ground. When it comes to spaceflight, sometimes testing is the most fun part of the engineering process.

Learn More:

UT – ExoMars is Back on Track for Mars in 2028

UT – The ExoMars Rover is Ready, now it Just Needs a new Ride to Mars

UT – ExoMars is Suspended. ESA is Looking for new Solutions to Replace Russian Components

In a recent test, NASA utilised an AI payload developed by Ubotica to show that the tech can help orbiting spacecraft provide better data.

Airbus’ latest generation (Constellation Optique 3D) CO3D satellites are set to launch today (25 July) aboard the Arianespace Vega-C rocket from French Guiana. The project is a high-profile collaboration between Airbus and the French Space Agency (CNES).

A navigation system created by Dublin-based space-tech manufacturer Innalabs has been fit on the satellite. The ARIETIS-NS system provides radiation-tolerant, high-precision inertial navigation, supporting the satellites’ critical attitude control and mission stability functions.

According to the start-up, its gyroscope unit is small in size, weight and the power it needs to run, and it operates with “extremely low noise” to avoid interference with telecoms and observation systems.

Designed and built by Airbus, the four CO3D dual-use satellites will deliver a global high-resolution Digital Surface Model service to CNES. It will also, the satellites will strengthen Airbus’ solutions of optical and radar satellites. The spacecrafts are set to operate for eight years, in pairs orbiting on opposite sides of the Earth.

“Being part of this project marks a proud milestone for Innalabs and for Irish engineering in space,” said John O’Leary, the CEO of Innalabs.

“We are honoured to contribute to this cutting-edge programme that is setting new standards in satellite performance and innovation.”

Last year, the Blanchardstown start-up’s navigation unit made its way with the European Space Agency (ESA) in a planetary defence mission, called Hera, to investigate the Didymos binary asteroid system.

While earlier this May, Innalabs secured its second contract to advance Earth’s planetary defence through ESA’s Ramses mission.

Ubotica’s AI upgrades NASA satellite

In a test earlier this month, NASA utilised an artificial-intelligence payload developed by Irish space-tech firm Ubotica, to show that the tech can help orbiting spacecraft provide more targeted and valuable data, faster.

The payload runs on Ubotica’s Space:AI platform, a commercially available space-capable processor. The test was conducted on CogniSAT-6, a CubeSat designed, built and operated by Open Cosmos.

The AI-run technology enabled an Earth-observing satellite, for the first time, to look ahead along its orbital path, rapidly process and analyse imagery with onboard AI and determine where to point an instrument.

The whole process took less than 90 seconds, without any human involvement, said NASA.

The concept is called Dynamic Targeting and the collaborators want to showcase its potential to enable orbiters to improve ground imaging by avoiding clouds, as well as hunt for specific, short-lived phenomena such as wildfires, volcanic eruptions and rare storms.

A paper on Dynamic Targeting was presented by NASA and Ubotica late last year at the International Symposium on Artificial Intelligence, Robotics and Automation for Space, in Brisbane, Australia.

“The idea is to make the spacecraft act more like a human. Instead of just seeing data, it’s thinking about what the data shows and how to respond,” explained Steve Chien, a technical fellow in AI at NASA’s Jet Propulsion Laboratory (JPL) and principal investigator for the Dynamic Targeting project.

“When a human sees a picture of trees burning, they understand it may indicate a forest fire, not just a collection of red and orange pixels. “We’re trying to make the spacecraft have the ability to say, ‘That’s a fire,’ and then focus its sensors on the fire.”

Ubotica CEO, Fintan Buckley, sees this as a shift from photographing everything, to photographing what matters.

“If you can be smart about what you’re taking pictures of, then you only image the ground and skip the clouds. That way, you’re not storing, processing, and downloading all this imagery researchers really can’t use,” said Ben Smith from JPL, an associate with NASA’s Earth Science Technology Office, which funds the Dynamic Targeting work.

With the cloud-avoidance capability now proven, the next test will be hunting for storms and severe weather. While another test will be to search for thermal anomalies like wildfires and volcanic eruptions.

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