Category: 7. Science

The underground fungi networks that help sustain Earth’s ecosystems are in need of urgent conservation action, according to researchers from the Society for the Protection of Underground Networks (SPUN).

The scientists found that 90 percent of mycorrhizal fungi biodiversity hotspots were located in unprotected ecosystems, the loss of which could lead to lower carbon emissions reduction rates, crop productivity and reduce the resilience of ecosystems to climate extremes.

Mycorrhizal fungi “cycle nutrients, store carbon, support plant health, and make soil. When we disrupt these critical ecosystem engineers, forest regeneration slows, crops fail and biodiversity above ground begins to unravel… 450m years ago, there were no plants on Earth and it was because of these mycorrhizal fungal networks that plants colonised the planet and began supporting human life,” said Executive Director of SPUN Dr. Toby Kiers, as The Guardian reported. “If we have healthy fungal networks, then we will have greater agricultural productivity, bigger and beautiful flowers, and can protect plants against pathogens.”

Excited to get these data into the hands of decision makers.

[image or embed]

— Society for the Protection of Underground Networks (SPUN) (@spun.earth) July 25, 2025 at 4:21 AM

Using over 2.8 billion fungal sequences from 130 countries, the scientists were able to create high-resolution, predictive biodiversity maps of the planet’s underground mycorrhizal fungal communities.

“For centuries, we’ve mapped mountains, forests, and oceans. But these fungi have remained in the dark, despite the extraordinary ways they sustain life on land,” Kiers said in a press release from SPUN. “This is the first time we’re able to visualize these biodiversity patterns — and it’s clear we are failing to protect underground ecosystems.”

The research was the first time a scientific application of SPUN’s 2021 world mapping initiative was done on a large scale.

^{Map from SPUN’s Underground Atlas shows predicted arbuscular mycorrhizal biodiversity patterns across underground ecosystems. Bright colors indicate higher richness and endemism. SPUN}

Mycorrhizal fungi help regulate the world’s ecosystems and climate by forming underground networks through which they provide essential nutrients to plants and draw more than 13 billion tons of carbon annually into soils — roughly a third of global fossil fuel emissions.

“Despite their key role as planetary circulatory systems for carbon and nutrients, mycorrhizal fungi have been overlooked in climate change strategies, conservation agendas, and restoration efforts,” the press release said. “This is problematic because disruption of networks accelerates climate change and biodiversity loss.”

Just 9.5 percent of fungal biodiversity hotspots are found inside existing protected areas.

“For too long, we’ve overlooked mycorrhizal fungi. These maps help alleviate our fungus blindness and can assist us as we rise to the urgent challenges of our times,” said Dr. Merlin Sheldrake, impact director at SPUN.

SPUN is featured in @science.org in a piece written by @humbertobasilio.bsky.social. Learn where some of the most unique fungal communities exist, such as West Africa’s Guinean forests, Tasmania’s temperate rainforests, and Brazil’s Cerrado savanna.

Read here: www.science.org/content/arti…

[image or embed]— Society for the Protection of Underground Networks (SPUN) (@spun.earth) July 25, 2025 at 6:33 AM

SPUN was launched with the aim of mapping fungal communities to develop resources for decision-makers in policy, law and climate and conservation initiatives.

“Conservation groups, researchers, and policymakers can use the platform to identify biodiversity hotspots, prioritize interventions, and inform protected area designations. The tool enables decision-makers to search for underground ecosystems predicted to house unique, endemic fungal communities and explore opportunities to establish underground conservation corridors,” SPUN said.

The findings of the study, “Global hotspots of mycorrhizal fungal richness are poorly protected,” were published in the journal Nature.

“These maps are more than scientific tools — they can help guide the future of conservation,” said lead author of the study Dr. Michael Van Nuland, lead data scientist at SPUN. “Food security, water cycles, and climate resilience all depend on safeguarding these underground ecosystems.”

Prominent advisors to the work include conservationist Jane Goodall, authors Paul Hawken and Michael Pollan, and founder of the Fungi Foundation Giuliana Furci.

“The idea is to ensure underground biodiversity becomes as fundamental to environmental decision-making as satellite imagery,” said Jason Cremerius, SPUN’s chief strategy officer.

The maps will be crucial in leveraging fungi for the regeneration of degraded ecosystems.

“Restoration practices have been dangerously incomplete because the focus has historically been on life aboveground,” said Dr. Alex Wegmann, a lead scientist at The Nature Conservancy. “These high-resolution maps provide quantitative targets for restoration managers to establish what diverse mycorrhizal communities could and should look like.”

The international network of 96 “Underground Explorers” from nearly 80 countries and more than 400 scientists are currently sampling the most remote and hard-to-access underground ecosystems on Earth, including those in Bhutan, Mongolia, Ukraine and Pakistan.

While just 0.001 percent of the surface of our planet has been sampled, SPUN’s dataset already includes more than 40,000 specimens representing 95,000 mycorrhizal fungal taxa.

“These maps reveal what we stand to lose if we fail to protect the underground,” Kiers said.

For a few days in December 2010, the world fantasized about the discovery of extraterrestrial life. NASA had sent out a press release to present “an astrobiological discovery” that would impact the search for life beyond Earth. The result was one of the biggest scientific controversies in recent history, and this Thursday a new chapter was written with the unilateral decision by the prestigious research journal Science to withdraw the study. In it, 12 scientists from NASA and the United States Geological Survey claimed to have discovered an alternative life form living in Mono Lake, California, that thrived on arsenic, a compound capable of annihilating any other known organism.

“Science has decided that this Research Article meets the criteria for retraction by today’s standards. Therefore, we are retracting the paper,” wrote Holden Thorp, editor-in-chief of the American journal, one of the most influential in the world, in an editorial on Thursday. The journal’s editor attributes his decision to the ongoing controversy surrounding the original study. The journal’s editors took months to publish the final version of the paper, and did so alongside several comments from other experts questioning its conclusions. A year later, two independent teams attempted to replicate the results and found no evidence that the life form in question, a bacterium named GFAJ-1, was capable of integrating arsenic into its DNA. The alleged discovery contradicted all other known life forms on the planet, which are based on six universal chemical compounds: carbon, oxygen, hydrogen, nitrogen, phosphorus, and sulfur.

According to the journal’s own rules, a study can only be retracted if its authors are found to have intentionally manipulated the data. To date, there is no evidence of this, the editor of Science acknowledges. But ever since the date when the study was published, the standards for retracting papers “have broadened,” he explains. After an independent ethics committee reviewed the case, it was decided to withdraw the work. In a blog post published alongside the retraction announcement, Thorpe and Science’s executive editor, Valda Vinson, issue a mea culpa: “a number of factors led to the publication of a paper with seriously flawed content, including the peer review process and editorial decisions that we made. With this retraction—and with all retractions and corrections—we acknowledge and take responsibility for the role that we played in the paper’s publication.”

Eleven of the 12 authors of the original study—one of them died in 2021—reject the retraction of their article, which they continue to stand by. The scientists are particularly critical of Science’s change of criteria, whose scope goes far beyond this journal and touches the heart of the most accepted procedures for conducting and publishing science worldwide. “We disagree with this standard, which extends beyond matters of research integrity. Disputes about the conclusions of papers, including how well they are supported by the available evidence, are a normal part of the process of science. Scientific understanding evolves through that process, often unexpectedly, sometimes over decades. Claims should be made, tested, challenged, and ultimately judged on the scientific merits by the scientific community itself,” they write in a digital letter to the journal.

The last signatory of this letter is Felisa Wolfe-Simon, probably the person who was most radically affected by this entire controversy. She was the preeminent voice at the famous press conference held at NASA headquarters in Washington, where she said: “We’ve cracked open the door to what’s possible for life elsewhere in the universe. And that’s profound,” the biologist asserted. Along with other colleagues, she also said that this discovery would require a new take on what constitutes life.

Wolfe-Simon rose to worldwide fame and, just days later, was crucified in a wave of criticism on the internet and emerging social platform like Twitter, now X.

The researcher left NASA and tried to continue working as a scientist, but she never managed to get published or attract new research grants. She quit science and became a professional oboe player, she told The New York Times.

The editors of Science now express their “empathy” with Wolfe-Simon for the “verbal abuse” she suffered. In recent years, Wolfe-Simon has tried to return to research on her own, for now outside of academic institutions. “I became radioactive,” she says of the media storm and the isolation she experienced.

The situation is very different from what other NASA scientists experienced, such as Chris McKay, who in 1996 announced the discovery of extraterrestrial life in a meteorite with then-U.S. President Bill Clinton, a finding that was soon dismissed. Despite this, he remains an active scientist at the space agency. The same is true of several of Wolfe-Simon’s fellow students, who remain active in the field of astrobiology. The possible difference is that in 2010, the internet made public lynchings possible practically in real time, beyond the pause and peer review required by science.

The biologist Pepa Antón, from the University of Alicante in eastern Spain, remembers the case well. She told reporters at the time that although the scientists presented “convincing” data, other teams would have to replicate the results. “Maintaining that DNA can be based on arsenic is very drastic; it required abundant evidence that has never been obtained,” Antón explains in a telephone conversation. The scientist is highly critical of the journal’s role. “I understand why the authors resent the retraction, because no one doubts that their behavior was always ethical. It amazes me how in science, rival factions sometimes emerge as if it were a football game. There were tremendous detractors as well as defenders, because ultimately, the idea of an alternative life to the known one was truly mind-blowing. It was very unfair. The ones who did the wrong thing were the people who published it,” she argues.

Ricardo Amils, a researcher at the Center for Astrobiology in Madrid, affiliated with NASA, was one of the most notable defenders of the study led by Wolfe-Simon, whom he knew personally. The scientist says that the retraction “is quite rare.” “Science doesn’t take into account the most important argument that the authors emphasize in their letter of protest, which has to do with the fact that the experiment replications refuting the work were not conducted under the same growth conditions of the microorganism, a fundamental element in microbiology,” Amils reasons.

Independent groups that attempted to breed the original arsenic-using bacteria found that these halomonads were indeed resistant to the compound, but it was not clear that they used it instead of phosphorus in their DNA.

These results were published in 2012, but the paper was not retracted then. Science editors argue that they have decided to withdraw the study now, in part because of renewed media pressure. “Any microbiologist knows that this is not a true refutation, but rather that under their conditions they were unable to reproduce the original results, concluding that DNA contamination was the cause of the misinterpretation of the retracted paper’s results. For me, this is an example of the direction science is taking in this world today. There must be important people who have demanded that, after so many years, a paper be refuted, using arguments that are more than scientifically questionable,” Amils ventures.

César Ángel Menor, a professor of Biochemistry at the University of Alcalá, Spain, considers the controversy a textbook case. “We used this article as an example of flawed science; I’ve even used it in class as a case study for students, in exercises in which they had to evaluate why the work reached incorrect conclusions,” he explained to the SMC website. “Now, finally, the article has been retracted, a decision I disagree with. Clearly, there was no misconduct or lack of professionalism on the part of the authors of the original article; it was simply errors in the interpretation and discussion of experimental data, something that is common in science,” he added.

Andrés de la Escosura, from the Autonomous University of Madrid, is surprised that it has taken so long to reach a decision. “We must ask ourselves whether this whole debate has been truly productive, and also about the excessive media coverage of some scientific organizations and certain lines of research,” he explains to SMC. “It’s important not to forget that the article by Wolfe-Simon et al. was announced with great fanfare at a press conference held by NASA, which now seems clearly excessive,” he adds.

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A startling new discovery at world’s most militarised glacier might put climate activists on the backfoot as deniers of climate change are celebrating.

A surprising image from National Aeronautics and Space Administration (NASA) revealed that Asia’s Karakoram mountain range has been gaining ice and merging, contrary to the popular belief that glaciers are melting due to global warming.

The image taken by the International Space Station (ISS) in 2023 shows that the Siachen glacier is slowly merging with the Lolofond and Teram Shehr glaciers.

Siachen is considered the most dangerous glacier on Earth as it is at the borders of three nuclear powered states, China, Pakistan, India – as well as conflict-affected nation Afghanistan.

The South Asian neighbours Pakistan and India have exchanged blows to take control of the region and both nations have been positioning troops on their side of the glacier since 1984.

This new discovery comes as a ray for hope as several climate studies have found that most glaciers worldwide are melting faster due to rising temperatures.

However, this is not the first report of localised glacial growth as previously Antarctica was also discovered to be reversing its decade long trend of melting.

Researchers based in Shanghai concluded in May that the Earth’s southernmost continent has seen a record amount of ice forming since 2021.

Despite isolated cases of ice accumulation, climate change still remains one of the greatest threats to the world as a 2023 study in Earth System Science Data warned that the merger of three glaciers in Asia’s Karakoram range might not last for long due to rising global temperatures.

NASA Earth Observatory revealed that the temperature of the Earth has risen by 1.1° Celsius since 1880. 

During this period, the moon reaches its first quarter phase on Friday August 1st. At that time the moon will be located 90 degrees east of the sun and will set near 23:00 local summer time (LST) on the previous evening. This weekend the waxing crescent moon will set during the early evening hours and will be long gone by the time the more active morning hours arrive. The estimated total hourly rates for evening observers this weekend should be near 4 as seen from mid-northern latitudes (45N) and 4 as seen from tropical southern locations (25S). For morning observers, the estimated total hourly rates should be near 20 as seen from mid-northern latitudes (45N) and 16 as seen from tropical southern locations (25S). The actual rates seen will also depend on factors such as personal light and motion perception, local weather conditions, alertness, and experience in watching meteor activity. Evening rates during this period are slightly reduced due to moonlight. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brighter meteors will be visible from such locations.

The radiant (the area of the sky where meteors appear to shoot from) positions and rates listed below are exact for Saturday night/Sunday morning July 26/27. These positions do not change greatly day to day so the listed positions may be used during this entire period. Most star atlases (available online and at bookstores and planetariums) will provide maps with grid lines of the celestial coordinates so that you may find out exactly where these positions are located in the sky. I have also included charts of the sky that display the radiant positions for evening, midnight, and morning. The center of each chart is the sky directly overhead at the appropriate hour. These charts are oriented for facing south but can be used for any direction by rotating the charts to the desired direction. A planisphere or computer planetarium program is also useful in showing the sky at any time of night on any date of the year. Activity from each radiant is best seen when it is positioned highest in the sky (culmination), either due north or south along the meridian, depending on your latitude. Radiants that rise after midnight will not reach their highest point in the sky until daylight. For these radiants, it is best to view them during the last few hours before dawn. It must be remembered that meteor activity is rarely seen at its radiant position. Rather they shoot outwards from the radiant, so it is best to center your field of view so that the radiant lies toward the edge and not the center. Viewing there will allow you to easily trace the path of each meteor back to the radiant (if it is a shower member) or in another direction if it is sporadic. Meteor activity is not seen from radiants that are located far below the horizon. The positions below are listed in a west to east manner in order of right ascension (celestial longitude). The positions listed first are located further west therefore are accessible earlier in the night while those listed further down the list rise later in the night.

 

These sources of meteoric activity are expected to be active this week

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The July gamma Draconids (GDR) were first noticed by Japanese observers of SonotoCo and the IMO’s network team of Sirko Molau and Juergen Rendtel in 2009. This stream is active from July 23-August 3 with maximum activity occurring on July 28. The radiant is currently located at 18:36 (279) +51, which places it in extreme southeastern Draco, 4 degrees southeast of the 2nd magnitude star known as Eltanin (gamma Draconis). The radiant also lies 11 degrees northwest of the brilliant zero magnitude star Vega (alpha Lyrae). These meteors are not well seen from the southern hemisphere as the radiant does not rise very high in their northern sky. Observers concentrating on this activity should face toward the northern sky near 23:00 LST best view these meteors. With an entry velocity of 27 km/sec., the average July gamma Draconid meteor would be of medium-slow velocity. In 2016, this stream produced a strong outburst that lasted approximately one hour. Nothing unusual has occurred since 2016. Some researchers feel these meteors are related to the kappa Cygnids, which are active in August. Normal rates for this shower is less than 1 shower member per hour no matter your location and perhaps 1 per hour at maximum as seen from northern latitudes.

The alpha Capricornids (CAP) are active from July 7 through August 13, peaking on July 30th. The radiant is currently located at 20:20 (305)  -11. This position lies northwestern Capricornus, 2 degrees north of the naked eye double star known as Algedi (alpha² Capricornii). Current rates are expected to be near 2 per hour no matter your location. These meteors are best seen near 01:00 LST, when the radiant lies highest in the northern sky. With an entry velocity of 23 km/sec., the average meteor from this source would be of medium-slow velocity.

The large Anthelion (ANT) radiant is currently centered at 21:08 (317) -15. This position lies in central Capricornus, 3 degrees north of the 4^th magnitude star known as Dorsum (theta Capricornii). This radiant is best placed near 02:00 LST when it lies on the meridian and is nearly overhead. Rates at this time should be near 2 per hour as seen from the northern hemisphere and 3 per hour as seen from south of the equator. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of medium-slow velocity.

The Southern delta Aquariids (SDA) are active from July 19 through August 13 with maximum activity occurring on July 30. The radiant is currently located at 22:31 (338) -17. This area of the sky is located in southwestern Aquarius, 4 degrees west of the 3rd magnitude star known as Skat (delta Aquarii). This radiant is best placed near 0300 LST, when it lies on the meridian and is nearly overhead. Hourly rates at this time should be near 3 as seen from the northern hemisphere and near 4 as seen from south of the equator.  At maximum these rates increase to 10 and 15 per hour. With an entry velocity of 41 km/sec., the average meteor from this source would be of medium velocity.

The Perseids (PER) are active from July 17 through August 29, with maximum activity occurring on August 13. The radiant is currently located at 01:47 (027) +54. This position lies in extreme western Perseus, 4 degrees northwest of the 4th magnitude star known as 51 Andromedae. This area of the sky is best placed for viewing during the last dark hour before dawn when it lies highest in the northeastern sky. Maximum activity is not until August 13th so current rates are expected to be near 2 as seen from the northern hemisphere and <1 as seen from south of the equator. With an entry velocity of 59 km/sec., the average meteor from this source would be of swift velocity. Viewers in the southern hemisphere have a limited view of this shower as the radiant only rises just before dawn.

Sporadic meteors are those meteors that cannot be associated with any known meteor shower. All meteor showers are evolving and disperse over time to the point where they are no longer recognizable. Away from the peaks of the major annual showers, these sporadic meteors make up the bulk of the activity seen each night. As seen from the mid-northern hemisphere (45N) one would expect to see during this period approximately 12 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 3 per hour. As seen from the tropical southern latitudes (25S), morning rates would be near 9 per hour as seen from rural observing sites and 2 per hour during the evening hours. Locations between these two extremes would see activity between these listed figures. Evening rates are slightly reduced due to moonlight.

The list below offers information in tabular form. Rates and positions in the table are exact for Saturday night/Sunday morning.

SHOWER	DATE OF MAXIMUM ACTIVITY	CELESTIAL POSITION	ENTRY VELOCITY	CULMINATION	HOURLY RATE	CLASS
		RA (RA in Deg.) DEC	Km/Sec	Local Summer Time	North-South
July gamma Draconids (GDR)	Jul 28	18:36 (279) +51	27	23:00	<1 – <1	III
alpha Capricornids (CAP)	Jul 31	20:20 (305)  -11	23	01:00	2 – 2	II
Anthelion (ANT)	–	21:08 (317)  -15	30	02:00	2 – 3	II
Southern delta Aquariids (SDA)	Jul 31	22:31 (338)  -17	41	03:00	3 – 4	I
Perseids (PER)	Aug 12	01:40 (025) +53	59	06:00	2 – <1	I

Class Explanation: A scale to group meteor showers by their intensity:

• Class I: the strongest annual showers with Zenith Hourly Rates normally ten or better.
• Class II: reliable minor showers with ZHR’s normally two to ten.
• Class III: showers that do not provide annual activity. These showers are rarely active yet have the potential to produce a major display on occasion.
• Class IV: weak minor showers with ZHR’s rarely exceeding two. The study of these showers is best left to experienced observers who use plotting and angular velocity estimates to determine shower association. These weak showers are also good targets for video and photographic work. Observers with less experience are urged to limit their shower associations to showers with a rating of I to III.
  

NASA’s Hubble Space Telescope and NASA’s Chandra X-ray Observatory have teamed up to identify a new possible example of a rare class of black holes. Called NGC 6099 HLX-1, this bright X-ray source seems to reside in a compact star cluster in a giant elliptical galaxy.

Just a few years after its 1990 launch, Hubble discovered that galaxies throughout the universe can contain supermassive black holes at their centers weighing millions or billions of times the mass of our Sun. In addition, galaxies also contain as many as millions of small black holes weighing less than 100 times the mass of the Sun. These form when massive stars reach the end of their lives.

Far more elusive are intermediate-mass black holes (IMBHs), weighing between a few hundred to a few 100,000 times the mass of our Sun. This not-too-big, not-too-small category of black holes is often invisible to us because IMBHs don’t gobble as much gas and stars as the supermassive ones, which would emit powerful radiation. They have to be caught in the act of foraging in order to be found. When they occasionally devour a hapless bypassing star — in what astronomers call a tidal disruption event— they pour out a gusher of radiation.

The newest probable IMBH, caught snacking in telescope data, is located on the galaxy NGC 6099’s outskirts at approximately 40,000 light-years from the galaxy’s center, as described in a new study in the Astrophysical Journal. The galaxy is located about 450 million light-years away in the constellation Hercules.

Astronomers first saw an unusual source of X-rays in an image taken by Chandra in 2009. They then followed its evolution with ESA’s XMM-Newton space observatory.

“X-ray sources with such extreme luminosity are rare outside galaxy nuclei and can serve as a key probe for identifying elusive IMBHs. They represent a crucial missing link in black hole evolution between stellar mass and supermassive black holes,” said lead author Yi-Chi Chang of the National Tsing Hua University, Hsinchu, Taiwan.

X-ray emission coming from NGC 6099 HLX-1 has a temperature of 3 million degrees, consistent with a tidal disruption event. Hubble found evidence for a small cluster of stars around the black hole. This cluster would give the black hole a lot to feast on, because the stars are so closely crammed together that they are just a few light-months apart (about 500 billion miles).

The suspected IMBH reached maximum brightness in 2012 and then continued declining to 2023. The optical and X-ray observations over the period do not overlap, so this complicates the interpretation. The black hole may have ripped apart a captured star, creating a plasma disk that displays variability, or it may have formed a disk that flickers as gas plummets toward the black hole.

“If the IMBH is eating a star, how long does it take to swallow the star’s gas? In 2009, HLX-1 was fairly bright. Then in 2012, it was about 100 times brighter. And then it went down again,” said study co-author Roberto Soria of the Italian National Institute for Astrophysics (INAF). “So now we need to wait and see if it’s flaring multiple times, or there was a beginning, there was peak, and now it’s just going to go down all the way until it disappears.”

The IMBH is on the outskirts of the host galaxy, NGC 6099, about 40,000 light-years from the galaxy’s center. There is presumably a supermassive black hole at the galaxy’s core, which is currently quiescent and not devouring a star.

Black Hole Building Blocks

The team emphasizes that doing a survey of IMBHs can reveal how the larger supermassive black holes form in the first place. There are two alternative theories. One is that IMBHs are the seeds for building up even larger black holes by coalescing together, since big galaxies grow by taking in smaller galaxies. The black hole in the middle of a galaxy grows as well during these mergers. Hubble observations uncovered a proportional relationship: the more massive the galaxy, the bigger the black hole. The emerging picture with this new discovery is that galaxies could have “satellite IMBHs” that orbit in a galaxy’s halo but don’t always fall to the center.

Another theory is that the gas clouds in the middle of dark-matter halos in the early universe don’t make stars first, but just collapse directly into a supermassive black hole. NASA’s James Webb Space Telescope’s discovery of very distant black holes being disproportionately more massive relative to their host galaxy tends to support this idea.

However, there could be an observational bias toward the detection of extremely massive black holes in the distant universe, because those of smaller size are too faint to be seen. In reality, there could be more variety out there in how our dynamic universe constructs black holes. Supermassive black holes collapsing inside dark-matter halos might simply grow in a different way from those living in dwarf galaxies where black-hole accretion might be the favored growth mechanism.

“So if we are lucky, we’re going to find more free-floating black holes suddenly becoming X-ray bright because of a tidal disruption event. If we can do a statistical study, this will tell us how many of these IMBHs there are, how often they disrupt a star, how bigger galaxies have grown by assembling smaller galaxies.” said Soria.

The challenge is that Chandra and XMM-Newton only look at a small fraction of the sky, so they don’t often find new tidal disruption events, in which black holes are consuming stars. The Vera C. Rubin Observatory in Chile, an all-sky survey telescope from the U.S. National Science Foundation and the Department of Energy, could detect these events in optical light as far as hundreds of millions of light-years away. Follow-up observations with Hubble and Webb can reveal the star cluster around the black hole.

In a startling revelation that could rewrite our understanding of the cosmos, scientists have proposed that the universe may not expand forever, but could instead meet a dramatic end in a colossal “Big Crunch.”

A new study, based on data from the Dark Energy Survey (DES) and the Dark Energy Spectroscopic Instrument (DESI), suggests that dark energy — the mysterious force believed to be pushing the universe apart — might not be constant as once thought. If true, this finding could have universe-shattering implications.

According to the researchers, who have published their findings in a preprint paper (awaiting peer review), dark energy may evolve over time, potentially turning negative in the distant future. Their work supports the axion-dark energy model (aDE), a newer theory that allows dark energy to fluctuate, unlike the long-accepted “cosmological constant” model.

If the cosmological constant becomes negative, as the data hints, gravity would ultimately win the tug-of-war with expansion. The universe’s outward growth would reverse, contracting until all matter, space, and time collapse into a dense singularity — the Big Crunch, the mirror image of the Big Bang.

The prediction paints a stark timeline: the universe, now 13.8 billion years old, might live for a total of 33.3 billion years. That means we’re already nearing the halfway point of cosmic history. In approximately 20 billion years, the entire universe could implode.

Astrophysicists stress that this scenario, while dramatic, isn’t set in stone. More observations and evidence are needed to validate the aDE model and confirm whether dark energy truly changes over time.

Still, the findings mark a profound shift in how scientists understand the future of everything. For the first time, the universe may not be running on an eternal timeline, but on a ticking cosmic clock. 

Disclaimer: Kindly avoid objectionable, derogatory, unlawful and lewd comments, while responding to reports. Such comments are punishable under cyber laws. Please keep away from personal attacks. The opinions expressed here are the personal opinions of readers and not that of Mathrubhumi.

Researchers have demonstrated that microscopic drug delivery containers can be magnetically steered to their targets, advancing the development of precision medicine for treating diseases such as cancer.

A multi-university team led by Jie Feng, a professor of mechanical science and engineering in The Grainger College of Engineering at the University of Illinois Urbana-Champaign, demonstrated that magnetic particles encapsulated in lipid vesicles can be used to steer the vesicles through fluids.

This work, published in the Royal Society of Chemistry journal Nanoscale, builds on earlier results showing that lipid vesicles can be engineered to release drugs when illuminated with laser light. The resulting system, combining both results, is a comprehensive prototype for precision and targeted drug delivery.

“The appeal of lipid vesicles for drug delivery is that their structure is similar to a cell, so they can be made to interact only with particular kinds of cells – a significant advantage for cancer treatment. One of the challenges to realizing such vehicles is knowing how to steer them to the correct site. We have shown how to do this using magnetic fields, solving the last big problem before we begin demonstrations ex vivo.”

Jie Feng, Professor, Mechanical Science and Engineering, The Grainger College of Engineering, University of Illinois Urbana-Champaign

Feng noted that existing medical technologies such as MRI could be repurposed to steer drug delivery vehicles with their magnetic fields, especially since these fields are designed to penetrate the human body. This can be achieved by encapsulating a superparamagnetic particle within the drug delivery vehicle, so it interacts with the externally controlled magnetic field.

The first step in creating magnetically steerable lipid vesicles was developing a reliable method to encapsulate magnetic particles in the vesicles. Vinit Malik, an Illinois Grainger Engineering graduate student in Feng’s laboratory and the study’s lead author, used the method of “inverted emulsion,” in which magnetic particles are added to a solution of dissolved lipids, leading to lipid droplets forming around the particles.

“It was not obvious what the best way to encapsulate lipid particles would be, so there was a large literature search and some trial and error,” Malik said. “We had to determine what the best magnetic particle size is, and then we had to figure out that the inverted emulsion method has the highest yields for encapsulated particles.”

Next, the researchers demonstrated that magnetic fields could direct the lipid vesicles. Malik developed a 3D-printable platform to mount the magnets securely on a microscope and to place the vesicles in a solution between the magnets. By observing the resulting motion, the researchers observed how speed varied with the ratio of magnetic particle size to vesicle size. They also confirmed that the vesicles only release their cargo when illuminated with laser light after moving to the end of the microfluidic channel.

While these experiments showed that the lipid vesicles moved as expected in magnetic fields, it was necessary to also understand how the magnetic particle pushes the vesicle from within to understand the behavior of the whole device.

The Illinois researchers partnered with investigators at Santa Clara University to computationally study the internal dynamics of the vesicle to predict the motion speed. Using the lattice Boltzmann method, they observed how the magnetic particle drags the whole vesicle when moving through a magnetic field.

“It allowed us to expand on our experiments, since it is otherwise difficult to observe or predict the response of such a vesicle system,” Malik said. “It gives us predictive power that will enhance design guidelines and allow us to understand the physical mechanisms governing the motion.”

Armed with experimental demonstrations of light-induced drug release and magnetic steering, Feng’s laboratory now aims to begin in vitro studies demonstrating that the lipid vesicles can be magnetically steered to specific locations through fluids like human blood.

“Our combined results lay the foundation for a comprehensive precision drug delivery system, and we’re ready to explore the potential uses in treatment,” Feng said. “We’re working towards the next step: using a real drug and performing an in vitro study in a microfluidic system that simulates features of biological environments.”