Today's Image of the Day from the European Space Agency features Abell S1063, a massive galaxy cluster located about 4.5 billion light-years from Earth. The galaxy cluster was captured by the Webb telescope in stunning detail.



According to <a href="https://www.esa.int/ESA_Multimedia/Images/2025/05/Webb_glimpses_the_distant_past" target="_blank" rel="noreferrer noopener">ESA</a>, the image is what’s known as a deep field - a long exposure of a single area of the sky, collecting as much light as possible to draw out the most faint and distant galaxies that don’t appear in ordinary images.&nbsp;



<h2 class="wp-block-heading" id="h-galaxies-of-the-early-universe">Galaxies of the early universe </h2>



Composed of nine separate snapshots taken at different near-infrared wavelengths over roughly 120 hours, this image represents Webb’s most detailed and deepest view of a single target so far.&nbsp;



Thanks to the gravitational lensing effect of Abell S1063, astronomers can peer deeper into the past than ever before - possibly viewing some of the universe’s very <a href="https://www.earth.com/news/ancient-galaxies-formed-from-the-earliest-elements-in-the-universe/" target="_blank" rel="noreferrer noopener">first galaxies</a>.



“The eye is first drawn, in this new NASA/ESA/CSA James Webb Space Telescope Picture of the Month, to the central mega-monster that is galaxy cluster Abell S1063. This behemoth collection of galaxies, lying 4.5 billion light-years from Earth in the constellation Grus (the Crane), dominates the scene,” noted ESA.



“Looking more closely, this dense collection of heavy galaxies is surrounded by glowing streaks of light, and these warped arcs are the true object of scientists’ interest: faint galaxies from the universe’s distant past.”



<h2 class="wp-block-heading" id="h-what-is-a-galaxy-cluster">What is a galaxy cluster?</h2>



Galaxy clusters are the largest known gravitationally bound systems and include not just galaxies, but also vast amounts of hot, X-ray-emitting gas and <a href="https://www.earth.com/news/the-true-nature-of-dark-matter-may-be-revealed-in-a-supernova/" target="_blank" rel="noreferrer noopener">dark matter</a>.&nbsp;



The galaxies within a cluster move through this hot intracluster medium, and their interactions can lead to phenomena like galaxy mergers or the stripping of gas from galaxies.&nbsp;



Galaxy clusters are important for studying the large-scale structure of the universe, the behavior of dark matter, and the evolution of galaxies over cosmic time.



<h2 class="wp-block-heading" id="h-hundreds-of-galaxies-bound-together-nbsp">Hundreds of galaxies bound together&nbsp;</h2>



As one of the most densely populated clusters known, Abell S1063 contains hundreds of galaxies bound together by gravity.&nbsp;



Its immense mass makes it an excellent example of a gravitational lens - a cosmic phenomenon where the cluster’s gravity bends and magnifies the light from galaxies far behind it.&nbsp;



This effect allows astronomers to observe incredibly faint and distant <a href="https://www.earth.com/news/milky-way-like-galaxies-were-present-in-the-early-universe/" target="_blank" rel="noreferrer noopener">galaxies</a> that would otherwise be beyond our detection limits.



<h2 class="wp-block-heading" id="h-studying-galaxy-evolution">Studying galaxy evolution</h2>



The cluster has been the focus of several major observational campaigns. It was prominently featured in the Hubble Space Telescope’s Frontier Fields program, which used its gravitational lensing power to study the early universe.&nbsp;



“The new imagery from Webb’s Near-Infrared Camera (NIRCam) takes this quest even further back in time,” said ESA.



“This image showcases an incredible forest of lensing arcs around Abell S1063, which reveal distorted background galaxies at a range of cosmic distances, along with a multitude of faint galaxies and previously unseen features.”



These observations are helping scientists probe the Cosmic Dawn era - the period shortly after the Big Bang.



<h2 class="wp-block-heading" id="h-exploring-the-cosmic-dawn-nbsp">Exploring the Cosmic Dawn&nbsp;</h2>



The Cosmic Dawn refers to a time in the history of the universe when the first stars and galaxies began to form and shine. This pivotal era occurred roughly between 100 million and 1 billion years after the Big Bang.&nbsp;



During the Dark Ages, the <a href="https://www.earth.com/news/fastest-feeding-black-hole-found-in-the-early-universe/" target="_blank" rel="noreferrer noopener">universe</a> had cooled enough for neutral hydrogen to form, but no luminous objects yet existed to light it up.&nbsp;



The birth of the first stars - often massive and short-lived - marked the beginning of the Cosmic Dawn. These stars emitted intense ultraviolet radiation, which gradually ionized the surrounding hydrogen gas in a process known as reionization.&nbsp;



This transformed the universe from a cold, opaque environment into one that was transparent to light, enabling the large-scale structure of the cosmos to take shape.



<h2 class="wp-block-heading" id="h-the-constellation-grus">The constellation Grus</h2>



Grus is a <a href="https://www.earth.com/news/super-jupiter-discovered-in-the-great-bear-constellation/" target="_blank" rel="noreferrer noopener">constellation</a> in the southern sky, its name derived from the Latin word for "crane," a type of large, graceful bird.&nbsp;



It was introduced in the late 16th century by the Dutch navigators Pieter Dirkszoon Keyser and Frederick de Houtman, during an era of celestial charting tied to European exploration of the southern hemisphere.&nbsp;



Grus is part of a group of constellations known as the "Southern Birds," which also includes Phoenix, Tucana, and Pavo.



This constellation lies near the celestial south pole and is best seen from the Southern Hemisphere during the months of August through October.&nbsp;



Image Credit: ESA/Webb, NASA &amp; CSA, H. Atek, M. Zamani



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Hundreds of galaxies illuminate the early universe 

Today's Image of the Day from the European Space Agency...

Today's Image of the Day from the European Space Agency features a Copernicus map of scorching summer temperatures across southern Europe.



“A powerful heatwave has been gripping large parts of southern Europe and North Africa, pushing air temperatures beyond seasonal norms and triggering widespread health and wildfire alerts. Among the hardest-hit countries are Spain, France, Italy, Greece, Cyprus, and Algeria,” said <a href="https://www.esa.int/ESA_Multimedia/Images/2025/07/Southern_Europe_s_land_and_sea_sizzles">ESA</a>.



“This image, a mosaic from five overlapping orbital passes in the morning of 29 June 2025, was captured by the <a href="https://www.esa.int/Applications/Observing_the_Earth/Copernicus/Sentinel-3">Copernicus Sentinel-3</a> mission’s Sea and Land Surface Temperature Radiometer.”&nbsp;



<h2 class="wp-block-heading" id="h-tracking-land-surface-temperatures-nbsp">Tracking land surface temperatures&nbsp;</h2>



According to ESA, the image reveals the temperature of the land surface - not air temperature.



Tracking land surface temperature is essential for predicting weather and climate patterns, assessing wildfire risk, helping <a href="https://www.earth.com/news/rising-temperatures-threaten-the-future-of-banana-farming/">farmers</a> plan irrigation, and informing urban design strategies to reduce heat.



“Unlike measurements of air temperature, this satellite instrument measures the actual thermal energy emitted from Earth’s surface, which typically registers higher than air temperatures.”



<h2 class="wp-block-heading" id="h-heat-dome-over-western-europe-nbsp">Heat dome over Western Europe&nbsp;</h2>



The image includes information from the Copernicus Marine Service, which shows that <a href="https://www.earth.com/news/ocean-temperatures-are-rising-faster-than-expected-and-likely-to-accelerate/">surface temperatures</a> are also hot across the Mediterranean Sea.



The ongoing heatwave is fueled by a high-pressure system stalled over Western Europe, known as a “heat dome.” This system traps hot, dry air beneath it, causing temperatures to rise steadily.&nbsp;



As it moves eastward, the dome pulls in even more hot air from North Africa, intensifying the extreme heat across the region.



<h2 class="wp-block-heading" id="h-heat-dome-over-the-united-states-nbsp">Heat dome over the United States&nbsp;</h2>



In June 2025, a heat dome developed over the central and eastern United States. It began forming around June 20 and persisted through the week.



The heat dome covered a large part of the country - from the Great Plains through the Midwest, Upper Midwest, Ohio and Tennessee River Valleys - and extended into the Mid‑Atlantic and Northeast regions.



More than 280 daily high-temperature records were shattered across the U.S., affecting some 130 million people under <a href="https://www.earth.com/news/extreme-heat-impacts-our-daily-routines-and-transportation/">heat warnings</a> or advisories.&nbsp;



Cities like New York, Baltimore, Philadelphia, Boston, Newark, Providence, and Raleigh saw triple-digit highs - some reaching more than 105 degrees.



<h2 class="wp-block-heading" id="h-public-health-concerns">Public health concerns</h2>



The heat dome not only caused dangerous daytime highs but also oppressive night-time warmth, with low temperatures often staying above 80 °F due to trapped heat. 



This persistent warmth strained power grids, led to emergency declarations, and triggered significant public health concerns.



Infrastructure suffered too: roads buckled in Missouri and softened asphalt sank vehicles in New York City, while a Baltimore Amtrak train stalled in a tunnel from the heat. 



Emergency measures included power reductions, heat shelters, and utility advisories in several states.



<h2 class="wp-block-heading" id="h-heat-domes-and-climate-change">Heat domes and climate change</h2>



Climate scientists emphasize that heat domes are fueled by anthropogenic <a href="https://www.earth.com/news/climate-change-earth-energy-imbalance-temperature-rise/">climate change</a>. These high-pressure patterns are occurring more frequently and enduring longer due to warming oceans, Arctic amplification, and altered jet stream behavior.&nbsp;



As global temperatures rise, the atmosphere can hold more moisture and energy, which intensifies heatwaves and makes them more persistent.&nbsp;



In particular, the weakened and meandering jet stream - a result of a warming Arctic - is allowing systems like heat domes to stall over regions for days or even weeks.



<h2 class="wp-block-heading" id="h-adapting-to-a-hotter-future">Adapting to a hotter future</h2>



Recent climate models show that events like the June 2025 heat dome (once considered rare), are becoming increasingly common.&nbsp;



What used to be a one-in-100-year heat event in many U.S. cities may now occur once a decade or even more often. This shift has serious implications not just for human health, but also for infrastructure, agriculture, and energy systems.&nbsp;



Power grids are pushed to their limits, roads and railways buckle under extreme heat, and crops suffer from both high temperatures and water stress.



Public health officials are especially concerned about the cumulative toll of prolonged <a href="https://www.earth.com/news/extreme-heat-is-pushing-parts-of-earth-beyond-human-survival/">extreme heat</a>. 



Nights that remain hot offer little relief and are particularly dangerous for vulnerable populations such as the elderly, young children, and people with chronic health conditions. 



Without sustained adaptation efforts - such as redesigning cities to reduce heat retention, expanding access to cooling centers, and modernizing energy infrastructure - the human and economic cost of extreme heat is expected to grow significantly in the coming decades.



Image Credit: ESA



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Heat dome scorches Southern Europe 

Today's Image of the Day from the European Space Agency features the Eagle Nebula, also known as Messier 16, which is located about 7,000 light-years away in the constellation Serpens.



The Eagle Nebula is one of the most iconic star-forming regions in our galaxy. It’s a vast cloud of gas and dust stretching roughly 70 light-years across. 



<h2 class="wp-block-heading" id="h-pillars-of-creation-nbsp">Pillars of Creation&nbsp;</h2>



What makes it especially famous is a portion of the <a href="https://www.earth.com/news/six-rogue-worlds-discovered-inside-a-young-star-forming-nebula/">nebula</a> captured by the Hubble Space Telescope in 1995 - an area called the "Pillars of Creation."&nbsp;



Some of these towering columns of gas are several light-years tall. The towers resemble sculpted fingers reaching out into space. Inside these pillars, new <a href="https://www.earth.com/news/serpens-nebula-image-reveals-how-stars-are-born/">stars</a> are being born as gravity pulls material together into dense cores that eventually ignite nuclear fusion.



The Pillars of Creation are often cited as a poetic example of the cosmic cycle of birth and destruction - where new stars are born even as the surrounding material is slowly destroyed by radiation.



<h2 class="wp-block-heading" id="h-hubble-image-of-the-eagle-nebula-nbsp">Hubble image of the Eagle Nebula&nbsp;</h2>



“This towering structure of billowing gas and dark, obscuring dust might only be a small portion of the Eagle Nebula, but it is no less majestic in appearance for it,” said <a href="https://esahubble.org/images/heic2507a/">ESA</a>.



“The new Hubble image is part of ESA/Hubble’s 35th anniversary celebrations. The cosmic cloud shown here is made of cold hydrogen gas, like the rest of the Eagle Nebula. In such regions of space new stars are born among the collapsing clouds.”&nbsp;



The hot, energetic stars emit intense ultraviolet light and powerful stellar winds that erode and sculpt the surrounding gas. The result is the creation of fantastical structures - like the narrow pillar with a blossoming head featured in the new image.



<h2 class="wp-block-heading" id="h-light-and-shadow-in-the-eagle-nebula">Light and shadow in the Eagle Nebula</h2>



The thick material in the pillar blocks most light, appearing dark and heavy against the backdrop. However, its edges glow where light from the more distant nebula shines through.&nbsp;



The striking colors reflect the chemistry and physics at play: blues signal ionized oxygen, reds indicate glowing hydrogen, and orange shows where starlight has managed to pierce the dust.



<h2 class="wp-block-heading" id="h-a-structure-under-siege">A structure under siege</h2>



Just out of frame lie the very stars responsible for shaping this dramatic pillar. Their radiation and winds continue to batter the cloud, compressing the gas and potentially triggering the birth of even more stars within.



For now, the pillar holds firm, but this stability is temporary. Over time, the relentless energy from newly formed <a href="https://www.earth.com/news/fluffy-molecular-clouds-may-change-our-understanding-of-star-formation/">stars</a> will eventually erode the entire structure.



“While the starry pillar has withstood these forces well so far, cutting an impressive shape against the background, eventually it will be totally eroded by the multitude of new stars that form in the Eagle Nebula,” explained ESA.



<h2 class="wp-block-heading" id="h-life-cycle-of-the-milky-way">Life cycle of the Milky Way</h2>



The nebula’s location in the Sagittarius Arm - one of the Milky Way’s major spiral arms - places it in a zone bustling with similar star-forming regions. This highlights the role of the Eagle Nebula in shaping the structure and the future of our galaxy.



Studies of the Eagle Nebula have revealed that the region is rich in young, hot stars - some of which are only a few million years old. These stars are in various stages of development, providing a natural laboratory for astronomers to study stellar life cycles.&nbsp;



<h2 class="wp-block-heading" id="h-evolution-of-the-eagle-nebula-nbsp">Evolution of the Eagle Nebula&nbsp;</h2>



Within the Eagle Nebula, there is a variety of stellar processes occurring in close proximity. Some stars are still forming within dense clouds of gas, while others have already matured and begun to emit powerful ultraviolet radiation.&nbsp;



The ongoing interaction between <a href="https://www.earth.com/news/star-formation-reignited-in-the-galaxy-leo-p-after-billions-of-years/">young stars</a> and their environment drives the evolution of the nebula itself.&nbsp;



As newly formed stars heat and disperse the gas and dust around them, they trigger further waves of star formation - or in some cases, halt it altogether.&nbsp;



This feedback loop not only influences the pace of star birth in the Eagle Nebula but also contributes to the broader life cycle of matter within the <a href="https://www.earth.com/news/milky-way-collision-may-change-everything-we-know-about-our-galaxy/">Milky Way</a>, enriching the galaxy with heavier elements forged in stellar cores.



Image Credit: ESA/Hubble &amp; NASA, K. Noll



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Eagle Nebula: Carving light from darkness

Today's Image of the Day from the European Space Agency features a portion of the Rosette Nebula, captured by the Hubble Space Telescope.



The Rosette Nebula is a vast cloud of gas and dust located in the constellation Monoceros, also known as the Unicorn.



Shaped like a blooming rose in deep space, it lies about 5,200 light-years from Earth and spans roughly 100 light-years in diameter.&nbsp;



<h2 class="wp-block-heading" id="h-image-of-the-rosette-nebula">Image of the Rosette Nebula </h2>



“<a href="https://www.earth.com/news/35-years-of-hubble-the-telescope-that-changed-our-view-of-the-universe/" target="_blank" rel="noreferrer noopener">Hubble</a> zooms into a small portion of the nebula that is only four light-years across (the approximate distance between our Sun and the neighboring Alpha Centauri star system),” noted <a href="https://www.esa.int/ESA_Multimedia/Images" target="_blank" rel="noreferrer noopener">ESA</a>.



“Dark clouds of hydrogen gas laced with dust are silhouetted across the image. The clouds are being eroded and shaped by the seething radiation from the cluster of larger stars in the center of the nebula.”&nbsp;



“An embedded star seen at the tip of a dark cloud in the upper right portion of the image is launching jets of plasma that are crashing into the cold cloud around it. The resulting shock wave is causing a red glow. The colors come from the presence of hydrogen, oxygen, and nitrogen.”



<h2 class="wp-block-heading" id="h-distinct-appearance-of-rosette">Distinct appearance of Rosette</h2>



Stellar winds and ultraviolet light are gradually carving out a cavity in the nebula’s center while simultaneously triggering new waves of <a href="https://www.earth.com/news/fluffy-molecular-clouds-may-change-our-understanding-of-star-formation/" target="_blank" rel="noreferrer noopener">star formation</a> along its dense edges.&nbsp;



The Rosette Nebula is often studied to understand the life cycle of stars and the complex interactions between radiation and interstellar material. 



Its intricate structure and visual appeal have made it a favorite target for both professional astronomers and astrophotographers.



<h2 class="wp-block-heading" id="h-nebulae-that-are-similar-to-rosette">Nebulae that are similar to Rosette</h2>



Compared to other famous nebulae, the Rosette Nebula stands out for its symmetry and floral appearance, which give it a distinct, iconic look. It's often compared to the Orion Nebula, which is much closer to Earth at about 1,300 light-years away and far brighter in the night sky. 



The <a href="https://www.earth.com/news/orion-nebula-destroys-an-oceans-worth-of-water-every-month/" target="_blank" rel="noreferrer noopener">Orion Nebula</a> is a bustling stellar nursery visible even to the naked eye, while the Rosette requires a telescope and is more diffuse and fainter despite being larger in actual size.



The Eagle Nebula, home to the famous "Pillars of Creation," shares a similar process of star formation and sculpting by radiation, but the Eagle has more dramatic, finger-like structures.&nbsp;



<h2 class="wp-block-heading" id="h-stellar-feedback-and-cosmic-evolution">Stellar feedback and cosmic evolution</h2>



The Lagoon Nebula and the Trifid Nebula, both in the constellation Sagittarius, also resemble the Rosette in that they are active star-forming regions, but they lie in a denser part of the <a href="https://www.earth.com/news/astronomers-found-something-strange-at-core-of-milky-way-galaxy-webb-meerkat/" target="_blank" rel="noreferrer noopener">Milky Way</a> and are often surrounded by a rich starfield.



What makes the Rosette Nebula particularly interesting scientifically is the clear interaction between its central star cluster and the surrounding gas, offering a textbook example of how massive stars influence their environment. 



It may not be as visually iconic as the Orion or as dynamic as the Eagle, but it's a beautiful and instructive example of stellar feedback and cosmic evolution.



<h2 class="wp-block-heading" id="h-history-of-the-rosette-nebula">History of the Rosette Nebula </h2>



The history of the Rosette Nebula, like many deep-sky objects, is a blend of observational discovery and increasing scientific understanding over time. 



Although it was likely spotted by earlier astronomers, its first documented observation was in the late 17th century by John Flamsteed, the first Astronomer Royal of England.&nbsp;



However, the <a href="https://www.earth.com/news/six-rogue-worlds-discovered-inside-a-young-star-forming-nebula/" target="_blank" rel="noreferrer noopener">nebula</a> itself was not fully recognized as a distinct object until the advent of astrophotography and improved telescopes in the 19th and 20th centuries.



<h2 class="wp-block-heading" id="h-star-clusters-of-the-enormous-cloud">Star clusters of the enormous cloud</h2>



The central star cluster, NGC 2244, was cataloged separately by William Herschel in the 18th century. Over time, astronomers realized that this cluster was embedded in a much larger, complex nebular structure.&nbsp;



As telescope technology advanced, astronomers identified several parts of the Rosette Nebula and gave them separate designations, including NGC 2237, NGC 2238, NGC 2239, and NGC 2246 - essentially referring to different regions of the same enormous cloud.



Observations from space-based telescopes like Chandra (X-rays) and Spitzer (infrared) helped map the energetic processes inside the nebula, revealing how radiation and stellar winds from NGC 2244 are triggering the birth of new stars in its surrounding regions.



Image Credit: ESA



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Rosette Nebula: A flower blooming in deep space

Today's Image of the Day from the European Space Agency features UGC 5460, a spiral galaxy that is located about 60 million light-years away in the constellation Ursa Major.&nbsp;



“This image combines four different wavelengths of light to reveal UGC 5460’s central bar of stars, winding spiral arms and bright blue star clusters. Also captured in the upper left-hand corner of this image is a far closer object: a star just 577 light-years away in our own galaxy,” said <a href="https://www.esa.int/ESA_Multimedia/Images" target="_blank" rel="noreferrer noopener">ESA</a>.



“UGC 5460 has hosted two recent supernovae named SN 2011ht and SN 2015as. It’s because of these two stellar explosions that Hubble targeted this galaxy, collecting data for three observing programmes that aim to study various kinds of supernovae.”&nbsp;



<h2 class="wp-block-heading" id="h-a-core-collapse-supernova-nbsp">A core-collapse supernova&nbsp;</h2>



SN 2015as is an example of a core-collapse supernova. This type of <a href="https://www.earth.com/news/supernova-explosions-could-damage-distant-planets/" target="_blank" rel="noreferrer noopener">supernova</a> occurs when the core of a massive star - typically with more than 8 times the mass of the sun - can no longer support its own gravity after exhausting its nuclear fuel. 



This causes the core to collapse under its own weight, leading to an extremely violent explosion. The collapse triggers the release of an enormous amount of energy, expelling the outer layers of the star into space.



In the aftermath of the explosion, a dense <a href="https://www.earth.com/news/shockingly-bright-carbon-monoxide-detected-in-supernova-remnant/" target="_blank" rel="noreferrer noopener">remnant</a> is created. This is often a neutron star or black hole, depending on the mass of the original star. Core-collapse supernovae are some of the most powerful events in the universe.



According to ESA, Hubble observations of SN 2015as will help researchers understand what happens when the expanding shockwave of a <a href="https://www.earth.com/news/supernova-dandelion-year-1181-leaves-behind-zombie-star-defying-death/" target="_blank" rel="noreferrer noopener">supernova</a> collides with the gas that surrounds the exploded star.



<h2 class="wp-block-heading" id="h-rare-stars-with-large-eruptions-nbsp">Rare stars with large eruptions&nbsp;</h2>



“SN 2011ht might have been a core-collapse supernova as well, but it could also be an impostor called a luminous blue variable. Luminous blue variables are rare stars that experience eruptions so large that they can mimic supernovae,” noted ESA.



“Crucially, luminous blue variables emerge from these eruptions unscathed, while stars that go supernova do not. Hubble will search for a stellar survivor at SN 2011ht’s location, and the explosion’s identity may be revealed at last.”



<h2 class="wp-block-heading" id="h-what-is-a-spiral-galaxy">What is a spiral galaxy?</h2>



Spiral galaxies are some of the most recognizable and beautiful structures in the universe. They are known for their distinctive arms that spiral outward from a central bulge.&nbsp;



These galaxies are typically composed of stars, gas, dust, and dark matter. The arms are often sites of intense <a href="https://www.earth.com/news/fluffy-molecular-clouds-may-change-our-understanding-of-star-formation/" target="_blank" rel="noreferrer noopener">star formation</a>, where clouds of gas collapse to form new stars. 



In the center of a spiral galaxy lies a dense concentration of older stars and, often, a supermassive black hole.



<h2 class="wp-block-heading" id="h-structure-of-a-spiral-galaxy-nbsp">Structure of a spiral galaxy&nbsp;</h2>



The structure of a spiral galaxy is generally divided into three main components: the disk, the bulge, and the halo.&nbsp;



The disk is where the spiral arms are located and contains most of the galaxy's visible stars and interstellar medium.&nbsp;



The bulge is a tightly packed region of older stars at the core, and the halo consists of a sparse collection of stars and globular clusters that surround the galaxy.&nbsp;



Spiral galaxies can be classified into different types based on the tightness and number of their spiral arms, as well as the size of their central bulge.



<h2 class="wp-block-heading" id="h-the-milky-way-galaxy">The Milky Way galaxy</h2>



Our solar system is located within a large spiral galaxy known as the Milky Way. The name refers to its appearance as a dim, milky band of light stretching across the night sky.&nbsp;



The term "Milky Way" comes from ancient Greek mythology, where it was associated the goddess Hera's milk spilling into the sky. In Greek, it was called "Galaxias Kyklos," meaning "milky circle."&nbsp;



Spanning about 100,000 light-years in diameter, the Milky Way is composed of stars, gas, dust, and dark matter. The galaxy has a distinct disk shape with spiral arms that wind outward from a central bulge, which houses a supermassive <a href="https://www.earth.com/news/milky-ways-black-hole-unleashes-mysterious-flares/" target="_blank" rel="noreferrer noopener">black hole</a>. 



Our sun is located in one of the spiral arms - known as the Orion Arm - positioned roughly halfway from the center to the outer edge.&nbsp;



The Milky Way is part of a small group of galaxies called the Local Group, which includes the Andromeda Galaxy and several smaller galaxies.



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Hubble views a spiral galaxy with stellar explosions

Apple,Cider,Vinegar,On,A,Metal,Spoon,Above,A,Glass

Every year, tens of millions of people around the world wrestle with bad moods and various levels of depression. Prescription drugs help many sufferers, yet side effects, cost, and uneven results often leave patients and clinicians on the lookout for other solutions. 



Then one day, as with all urban myths, one person told another who told another about a home remedy that never seems to fail. If you want to <a href="https://www.earth.com/news/is-depression-contagious-couples-may-share-it-through-kissing/">beat depression</a>, taking just one spoonful of vinegar every day will wash those blue away. 



When you stop and think about it for a minute, diet does seem like an obvious place to turn for cures to most any ailment. After all, the body and mind operate on what we feed them.



Could the same sour splash that wakes up a salad also nudge a weary mind toward optimism? 



Two small <a href="https://clinicaltrials.gov/study/NCT04706806" target="_blank" rel="noreferrer noopener">clinical trials suggests</a> that the idea of treating depression with a spoonful of vinegar is definitely worth more attention from medical professionals and the public.



<h2 class="wp-block-heading" id="h-studying-vinegars-impact-on-depression">Studying vinegars impact on depression</h2>



Fermented vinegars have had a place in folk remedies for centuries, prized for their ability to tame <a href="https://www.earth.com/news/drinking-this-amount-of-water-per-day-helps-control-blood-sugar-levels-in-people-with-diabetes/" target="_blank" rel="noreferrer noopener">blood sugar spikes</a> and add zest without salt or fat. 



Scientific studies over the past decade have confirmed some metabolic perks, yet mental health has been missing from the conversation. 



That gap inspired a team of nutrition researchers to see whether swallowing some vinegar on a regular schedule could ease depression by influencing mood-related chemistry as well as subjective feelings.



Led by <a href="https://www.asu.edu/" target="_blank" rel="noreferrer noopener">Arizona State University</a> dietitian Haley Barrong, the investigators recruited 28 overweight but otherwise healthy adults and randomly assigned them to one of two groups. 



Half drank two tablespoons of red wine vinegar diluted in water twice a day, while the rest swallowed a capsule containing only a trace of vinegar.



<h2 class="wp-block-heading" id="h-what-the-team-learned">What the team learned</h2>



Over four weeks, all participants completed the Center for Epidemiological Studies Depression questionnaire (<a href="https://nida.nih.gov/sites/default/files/Mental_HealthV.pdf" target="_blank" rel="noreferrer noopener">CES-D</a>) and the Patient Health Questionnaire-9 (<a href="https://med.stanford.edu/fastlab/research/imapp/msrs/_jcr_content/main/accordion/accordion_content3/download_256324296/file.res/PHQ9%20id%20date%2008.03.pdf" target="_blank" rel="noreferrer noopener">PHQ-9</a>).



Scores on the CES-D hardly budged, yet the PHQ-9 told another story. In the vinegar group, reported depressive symptoms fell by an average of 42 percent, compared with an 18 percent dip in the pill group. 



After reviewing the data, the authors wrote, “This data provides additional support that daily vinegar ingestion over four weeks can improve self-reported depression symptomology in generally healthy adults and that alterations in [<a href="https://www.earth.com/news/vitamin-b-paradox-supplement-linked-to-heart-disease-risk/" target="_blank" rel="noreferrer noopener">vitamin B3</a>] metabolism may factor into this improvement.”



<h2 class="wp-block-heading" id="h-vinegar-depression-and-blood">Vinegar, depression, and blood</h2>



The team also collected blood samples to watch biochemical pathways at work. The most striking change was an 86 percent surge in nicotinamide, a form of vitamin B3 that feeds into the NAD⁺ salvage pathway responsible for cellular energy recycling. 



Higher nicotinamide aligns with lower inflammation, a relationship that has caught psychiatric interest before. 



Two metabolites - <a href="https://www.earth.com/news/eating-less-of-this-amino-acid-isoleucine-boosts-lifespan-in-mice-an-average-of-33-percent/">isoleucine</a>, a branched-chain amino acid, and <a href="https://pubchem.ncbi.nlm.nih.gov/compound/Isobutyric-acid" target="_blank" rel="noreferrer noopener">isobutyric acid</a> - shifted as well, hinting that vinegar tweaks broader metabolic networks tied to mood regulation.



“Depressive disorders are the most prevalent mental health conditions in the world,” write the researchers. 



“The commonly prescribed antidepressant medications can have serious side effects, and their efficacy varies widely. Thus, simple, effective adjunct therapies are needed.”



<h2 class="wp-block-heading" id="h-how-vinegar-might-lift-mood">How vinegar might lift mood</h2>



Several mechanisms could explain the modest improvements. Acetic acid, the defining ingredient in vinegar, activates AMP-activated <a href="https://www.earth.com/news/studies-learn-the-exact-amount-of-time-you-should-spend-training-to-build-muscle/">protein kinase</a>, an energy sensor linked to <a href="https://pubmed.ncbi.nlm.nih.gov/25308486/" target="_blank" rel="noreferrer noopener">NAD⁺ production</a>. 



More NAD⁺ means brain cells repair DNA damage more effectively and maintain healthy mitochondria. 



Another possibility involves the gut. <a href="https://www.earth.com/news/scientifically-proven-tips-for-better-kombucha-brewing/">Acetic acid</a> can encourage growth of friendly bacteria that generate neurotransmitter precursors, forging a gut-brain feedback loop many neuroscientists now consider crucial to emotional balance.



Lab work in mice has already shown that boosting NAD⁺ protects neurons from stress hormones, while human studies connect higher dietary vitamin B3 with lower depression risk. 



The present human trial knits those ideas together: swallow vinegar, raise nicotinamide levels, and perhaps give the brain an energetic lift.



<h2 class="wp-block-heading" id="h-depression-vinegar-and-health">Depression, vinegar, and health</h2>



None of this turns vinegar into a standalone treatment. The experiment lasted only a month, involved people with mild symptoms, and lost some statistical punch after adjusting for baseline scores. 



Still, swallowing a familiar pantry staple twice a day costs pennies and carries few risks for most adults. 



“Future research examining the effects of vinegar administration in clinically depressed or at-risk populations, and those on antidepressant medications, is warranted," the authors concluded.



“A focus on mechanisms and large patient samples will strengthen the science and provide the evidence to more firmly demonstrate vinegar's role in health promotion.” 



Until those larger trials wrap up, dietitians may simply remind clients that incorporating two tablespoons of red wine or apple cider vinegar into meals is safe for most, provided they dilute it and protect their teeth by rinsing with water.



<h2 class="wp-block-heading" id="h-future-studies-on-depression-and-vinegar">Future studies on depression and vinegar</h2>



People interested in trying the routine might start by whisking vinegar into dressings or stirring it into a tall glass of water before lunch and dinner. 



Anyone with <a href="https://www.earth.com/news/junk-food-diet-triggers-lasting-changes-in-the-brain/">acid reflux</a>, kidney issues, or current prescriptions should check with a clinician first. 



<a href="https://www.earth.com/news/how-nature-heals-outdoor-activities-greatly-improve-mental-health/">Mental health</a> professionals could eventually blend such low-cost dietary tweaks with therapy and medication, tailoring care to each person’s biology and preferences.



The notion that mood can shift alongside something as ordinary as a mealtime condiment highlights how tightly body and mind intertwine.



Vinegar will never replace professional treatment, yet its potential to turn that frown upside down - especially for those reluctant to take pharmaceuticals - deserves the careful follow-up studies that this research team calls for. 



The full study was published in the journal <a href="https://www.mdpi.com/2072-6643/16/14/2305" target="_blank" rel="noreferrer noopener">Nutrients</a>.



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Study identifies a much easier and cheaper way to treat depression than with prescription drugs

Every year, tens of millions of people around the world...

Archaeologists in central France have uncovered two swords, buried for roughly 2,300 years, that still glint with inlaid glass and copper. The <a href="https://www.inrap.fr/la-necropole-celtique-des-ancises-creuzier-le-neuf-allier-19987" target="_blank" rel="noreferrer noopener">finds</a> sit among more than one hundred grave pits on a hill overlooking the small town of Creuzier‑le‑Neuf.



The site’s burial ground dates to the early fourth century B.C. and covers nearly 7,000 square feet, a scale rarely matched for <a href="https://www.worldhistory.org/La_Tene_Culture/" target="_blank" rel="noreferrer noopener">La Tène‑period France</a>. 



Benjamin Oury of the National Institute for Preventive Archaeological Research (<a href="https://www.inrap.fr/en" target="_blank" rel="noreferrer noopener">INRAP</a>), who led the excavation, says every object pulled from the soil helps reconstruct Celtic life at a political crossroads.



<h2 class="wp-block-heading" id="h-celtic-swords-and-burial-sites">Celtic swords and burial sites</h2>



Soil acidity has stripped the skeletons away, yet iron‑oxide cocoons preserved many <a href="https://www.earth.com/news/metal-detectors-find-a-2500-year-old-dagger-that-opens-a-new-window-on-history/">metal</a> offerings in place. 



Almost half of the graves still contained jewelry, weaponry, or costume fittings that slid free once conservators separated the rust from the soil matrix.



The enclosure itself is quadrangular, edged by a ditch wide enough to signal communal effort rather than family memory. 



Orientation north to south keeps the rows tidy, hinting at coordinated <a href="https://www.earth.com/news/archaeologists-discover-141-ancient-gold-coins-some-from-a-little-known-roman-emperor/">funeral rites</a> rather than hurried internment.



Only one tomb held a cremation, and it came with a painted clay vase whose red spirals echo Mediterranean pottery fashions. 



Work at other <a href="https://www.history.com/articles/iron-age" target="_blank" rel="noreferrer noopener">Second Iron Age</a> cemeteries shows such decorated urns riding trade routes that reached the Rhône Valley and beyond.



<h2 class="wp-block-heading" id="h-metalwork-that-defies-time">Metalwork that defies time</h2>



Eighteen fibulas, some iron and others copper‑alloy, surfaced in fragile bundles but stabilized cleanly in <a href="https://www.viennalab.com/" target="_blank" rel="noreferrer noopener">Vienna’s CREAM laboratory</a>. 



One brooch carries a silver‑leafed gem while another shows <a href="https://www.numisantica.com/en/ancient-beads-jewellery/ancient-beads/iron-age-celtic-glass-stratified-eye-bead/a-19705-10000099" target="_blank" rel="noreferrer noopener">ocelli</a>, or eye‑shaped bosses that Celtic artisans favored during the fifth and fourth centuries B.C..



Bracelets came up in pairs for several burials, their terminals socketed so neatly that the clasp disappears when closed. 



A matched set bears concentric rings so deeply punched that fresh hammer marks still catch light under magnification.



Copper spheres sit atop some clasps like berries on a stem, a motif echoed on harness fittings found in Champagne burials two hundred miles away. 



Shared decorative grammar points to workshops trading not only goods but patterns across tribal frontiers.



<h2 class="wp-block-heading" id="h-two-celtic-swords-two-stories">Two Celtic swords, two stories</h2>



“The longer sword has all the characteristics of a functional weapon,” said <a href="https://www.researchgate.net/profile/Vincent-Georges" target="_blank" rel="noreferrer noopener">Vincent Georges</a>, archaeologist at INRAP. One Celtic sword stretches long enough to ride at a horseman’s waist, its sheath edged by cabochons of glass paste. 



Textile fragments clung to the back plate of the scabbard, probably the deceased’s cloak, and X‑ray stripes show the belt rings had never been pried away. 



Even oxidation respected the original geometry, letting conservators measure the blade within two millimeters of its working length.



The second weapon is shorter, leaf‑shaped, and clearly <a href="https://www.earth.com/news/mystery-of-pirunkirkko-the-cave-that-whispers-secrets-of-the-past/">ceremonial</a>, its copper hilt tipped with small bronze balls called antennae. 



Georges added that the piece is “more or less contemporary with the Celtic incursions in northern Italy and the sacking of Rome in 387 B.C.”



<h2 class="wp-block-heading" id="h-tracing-the-swastika-s-earlier-meaning">Tracing the swastika’s earlier meaning</h2>



Two gems on the ceremonial sheath carry neat engravings of the <a href="https://landiscenter.lafayette.edu/2017/02/06/swastika-the-symbol-of-good-fortune-or-that-of-the-nazi/" target="_blank" rel="noreferrer noopener">swastika</a>, a cross with right‑angled arms that ancient cultures read as luck or cosmic motion. 



<a href="https://www.lboissoneault.com/about" target="_blank" rel="noreferrer noopener">Historian Lorraine Boissoneault</a> documents the emblem on artifacts from India to the Mississippi Valley long before its Nazi appropriation.



Classical collections show the motif spreading across the Mediterranean by the sixth century B.C., then drifting north with Celtic migration. 



Its presence here, tucked beside a crescent and full circle inlaid on the blade itself, suggests celestial or solar connotations rather than any martial boast.



The <a href="https://arkeonews.net/exceptional-iron-age-artifacts-discovered-at-celtic-necropolis-in-central-france/" target="_blank" rel="noreferrer noopener">Creuzier‑le‑Neuf sword</a> adds the earliest Western European example carved into gemstone, a technique more at home in <a href="https://quod.lib.umich.edu/b/bulletinfront/0054307.0015.104/--hellenistic-archives-from-tel-kedesh-israel-and-seleucia?rgn=main;view=fulltext" target="_blank" rel="noreferrer noopener">Hellenistic seal rings</a>. Such hybrid artistry underscores how porous cultural borders were, even during localized feuds.



<h2 class="wp-block-heading" id="h-on-the-frontier-of-celtic-power">On the frontier of Celtic power</h2>



Creuzier‑le‑Neuf lay where the Arverni, Aedui, and Bituriges territories overlapped, a liminal patch that prospered on exchange and occasional tension. 



Trade beads from Mediterranean workshops enter local rivers just as Arverni bronze flows south into alpine passes.



History remembers the wider Celtic world for routing Roman troops at the Battle of Allia on July 18, 387 B.C., a clash that left Rome paying gold for its freedom. 



The ornamental Celtic sword’s dating to that generation hints that prestige weapons doubled as status badges while real steel rode to war.



All three tribes maintained fortified oppida within a day’s march, yet they buried their dead together here, suggesting overlapping kin networks or shared sacred ground. 



<a href="https://www.earth.com/news/bronze-age-people-abandoned-meat-for-millet-3500-years-ago/">Isotope work</a> planned for the sheath alloys may reveal whether ores came from <a href="https://www.mindat.org/loc-332900.html" target="_blank" rel="noreferrer noopener">Massif Central mines</a> or more distant sources tied to intertribal alliances.



Yet no slash notches scar the blade edges, confirming Georges’ view that the shorter sword lived mainly as insignia of rank. Function bowed to symbolism, and symbolism borrowed from everywhere.



<h2 class="wp-block-heading" id="h-what-the-artifacts-tell-us">What the artifacts tell us</h2>



Without bones to speak for them, the objects narrate diet, trade, and hierarchy. Cabochons likely held imported glass, bracelets mimic <a href="https://www.world-archaeology.com/features/la-tene/" target="_blank" rel="noreferrer noopener">La Tène type‑A catalogs</a>, and the swords compress the story of shifting alliances into metal and stone.



Oury calls the site “a classroom for understanding how identity was displayed in death,” and future residue studies on corrosion layers may pinpoint burial textiles or pigments. 



Conservation continues, but plans for a regional museum display are already under discussion.



Each cleaned item reminds visitors that symbols travel farther than armies. A sign once bent toward thunder gods now rests on a sword that never drew blood, carried by someone who wanted to be remembered, and was.



Photo: <a href="https://www.inrap.fr/sites/inrap.fr/files/thumbnails/image/f250211_inrapmocreuzier_143.jpg" target="_blank" rel="noreferrer noopener">Flore Giraud</a>, Inrap.



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Archaeologists find 2,300-year-old swords adorned with gems and ancient symbols

Archaeologists in central France have uncovered two swords, buried for...

Cell biology is a world of constant motion and hidden structures. Much of what we know about cells comes from decades of research using microscopes, stains, and models. Yet, even in this well-charted territory, surprises still emerge - enter the "hemifusome."



This previously unknown organelle may help explain how cells sort, recycle, and discard their internal cargo. This function is vital to life and is often disrupted in instances of genetic disease.



The discovery of this organelle, which was made by scientists at the <a href="https://www.virginia.edu" target="_blank" rel="noreferrer noopener">University of Virginia</a> and the National Institutes of Health (<a href="https://www.nih.gov" target="_blank" rel="noreferrer noopener">NIH</a>), offers a new lens through which to study the inner workings of the cell. 



It also presents a possible turning point for understanding diseases where cellular housekeeping breaks down. Using cutting-edge imaging tools, researchers have caught this <a href="https://www.earth.com/news/cambrian-explosion-fossils-push-back-the-rise-of-complex-life/">organelle</a> in action and outlined its potential impact on health and medicine.



<h2 class="wp-block-heading" id="h-introducing-the-hemifusome">Introducing the hemifusome</h2>



The hemifusome is not a static component but a temporary structure that appears and disappears depending on the cell’s needs. 



It consists of two vesicles joined together by a partial membrane connection called a hemifusion diaphragm.



In this configuration, the vesicles do not fully merge but maintain a shared boundary that allows them to interact without blending entirely.



"This is like discovering a new recycling center inside the cell," said researcher Seham Ebrahim, Ph.D., of UVA's Department of Molecular Physiology and Biological Physics. 



"We think the hemifusome helps manage how <a href="https://www.earth.com/news/third-state-of-existence-beyond-life-and-death-confirmed-by-scientists/">cells</a> package and process material, and when this goes wrong, it may contribute to diseases that affect many systems in the body."



These hemifused vesicles appear in two configurations. In the direct form, a smaller vesicle is attached to the outer side of a larger one, whereas in the flipped version, the smaller vesicle is embedded on the inner, or luminal, side. 



In both cases, a dense particle called a proteolipid nanodroplet anchors the structure at the junction, possibly guiding its formation and stability.



<h2 class="wp-block-heading" id="h-how-the-hemifusome-appears">How the hemifusome appears</h2>



To study hemifusomes, researchers turned to cryo-electron tomography (cryo-ET). This imaging method freezes cells rapidly, preserving them close to their natural state. 



Unlike traditional <a href="https://www.earth.com/news/watching-electrons-move-1-quintillionth-of-second-attoseconds-attomicroscopy/">electron microscopy</a>, which can distort or destroy delicate structures, cryo-ET allows scientists to see cellular architecture as it truly exists.



By scanning the outer edges of four mammalian cell types, COS-7, HeLa, RAT-1, and NIH/3T3, the team identified hundreds of hemifusomes. These organelles made up nearly 10 percent of all membrane-bound vesicles in those regions. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/07/hemifused-vesicles_cryo-electron-tomography_Nature-Communications_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2025/07/hemifused-vesicles_cryo-electron-tomography_Nature-Communications_1s.webp" alt="Cryo-electron tomography observation of hemifused vesicles at the leading edge of cultured cells. Credit: Nature Communications (2025)" class="wp-image-1976051"/></a><figcaption class="wp-element-caption">Cryo-electron tomography observation of hemifused vesicles at the leading edge of cultured cells. Click image to enlarge. Credit: Nature Communications (2025)</figcaption></figure>



Their consistency across <a href="https://www.earth.com/news/why-millions-of-fungal-species-still-remain-unknown/">cell</a> types suggests they are not rare anomalies but common cellular components.



"You can think of vesicles like little delivery trucks inside the cell," said Ebrahim, of UVA's Center for Membrane and Cell Physiology. "The hemifusome is like a loading dock where they connect and transfer cargo. It's a step in the process we didn't know existed."



<h2 class="wp-block-heading" id="h-what-makes-the-hemifusome-unique">What makes the hemifusome unique</h2>



Hemifusomes stand out not just for their shape, but for what’s inside them. The larger vesicle usually contains granular material, similar to what is seen in <a href="https://www.earth.com/news/mitochondria-cells-batteries-leaking-causes-inflammation-diseases/">endosomes</a> and ribosome-associated vesicles.



But the smaller vesicle shows a smooth, translucent interior. This likely reflects a protein-free or dilute aqueous solution, setting it apart from other vesicles in the cell.



The hemifusion diaphragm itself is unusually large, about 160 nanometers in diameter, far bigger than the 10 nanometer diaphragms seen in standard vesicle fusion <a href="https://www.earth.com/news/gold-eating-fungus-discovery-could-revolutionize-the-search-for-metals-and-minerals-on-earth-asteroids-and-other-planets/">events</a>. These extended diaphragms appear stable, not fleeting, suggesting they may be designed to last. 



In some cases, the diaphragm grows large enough to engulf the entire smaller vesicle into the larger one’s bilayer, creating a lens-like shape known in simulations as dead-end hemifusion. Seeing this in actual cells challenges the idea that such formations are purely theoretical.



<h2 class="wp-block-heading" id="h-anchors-and-architects-of-the-organelle">Anchors and architects of the organelle</h2>



One consistent feature at the heart of hemifusomes is the dense proteolipid nanodroplet, or PND. About 42 nanometers in diameter, these droplets are lodged at the rim of the hemifusion site. 



Their content, lipids and proteins, suggests they may help build or stabilize the hemifused structure.



These PNDs have never been observed in such a role before. Some appear free in the cytoplasm, others are embedded in membranes. Researchers propose that PNDs may serve as scaffolds for assembling new vesicles. 



As the PND integrates into a membrane, it may kickstart the formation of the smaller vesicle seen in hemifusomes.



This process, described as <a href="https://www.sciencedirect.com/topics/neuroscience/vasculogenesis" target="_blank" rel="noreferrer noopener">de novo vesiculogenesis</a>, stands apart from classical vesicle fusion. The presence of a unique, translucent vesicle and the absence of known docking steps indicate the hemifusome may follow its own assembly path.



<h2 class="wp-block-heading" id="h-are-hemifusomes-related-to-endosomes">Are hemifusomes related to endosomes?</h2>



Given their location and size, hemifusomes resemble some endosomal structures. To investigate this further, the researchers traced the journey of gold nanoparticles, common markers used to map endocytic activity. 



The particles entered known endosomes and <a href="https://www.earth.com/news/tricking-cells-into-thinking-they-ate-less-food-can-slow-aging-process/">lysosomes</a> but never appeared inside hemifusomes. This absence suggests that hemifusomes do not belong to the classical endocytic pathway.



Instead, they may represent a separate system operating independently of the cargo sorting carried out by proteins like ESCRT. This distinction may have wide implications for how we understand vesicle traffic inside cells.



<h2 class="wp-block-heading" id="h-multivesicular-bodies-and-disease">Multivesicular bodies and disease</h2>



Some hemifusomes evolve into more complex structures. The study observed compound hemifusomes that contained multiple vesicles, all partially fused. 



These could be early versions of <a href="https://www.sciencedirect.com/topics/medicine-and-dentistry/multivesicular-body" target="_blank" rel="noreferrer noopener">multivesicular bodies</a> (MVBs), which cells use to break down and recycle internal material.



In the canonical model, ESCRT proteins form inward buds that eventually pinch off inside a larger vesicle. But in hemifusomes, vesicles grow inward through hemifusion and expand with the help of PNDs. 



This alternative route might explain how MVBs form in ways not covered by traditional theories.



One such condition affected by these pathways is Hermansky-Pudlak syndrome. It is a genetic disorder marked by defects in pigmentation, lung function, vision, and bleeding. <a href="https://www.earth.com/news/damaged-mitochondria-recycled/">Cellular recycling</a> issues are central to the disease.



Understanding the hemifusome may help explain these disruptions and lead to future treatments.



<h2 class="wp-block-heading" id="h-a-new-model-for-vesicle-formation">A new model for vesicle formation</h2>



The study proposes a full model where PNDs trigger the formation of translucent vesicles that partially fuse with larger ones, forming hemifusomes. 



These structures may then bud inward, transforming into flipped hemifusomes. Over time, they could scission off as free vesicles inside MVBs.



In contrast to the ESCRT system, which requires tight protein coordination, this mechanism relies on structural and biophysical cues. 



It also sidesteps the need for large lipid donations from other organelles, solving a long-standing puzzle in vesicle formation research.



"This is just the beginning," Ebrahim said. "Now that we know hemifusomes exist, we can start asking how they behave in healthy cells and what happens when things go wrong. That could lead us to new strategies for treating complex genetic diseases."



<h2 class="wp-block-heading" id="h-what-comes-next">What comes next</h2>



The implications of this discovery stretch far beyond cell biology. By offering a new pathway for how cells build and manage internal compartments, the hemifusome challenges decades of assumptions. 



It also invites new thinking about disease, especially conditions where cells fail to manage their waste.



Future research will focus on identifying what proteins guide hemifusome formation and how PNDs are created. 



Scientists also want to know if these structures exist in other parts of the cell, not just at the periphery. Advanced imaging tools and genetic models will be key to answering these questions.



In a field where many believed the major organelles were already mapped, the hemifusome serves as a reminder. The cell still holds secrets. And some of them could lead to cures.



The study is published in the journal <a href="https://www.nature.com/articles/s41467-025-59887-9" target="_blank" rel="noreferrer noopener">Nature Communications</a>.



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New structure found inside human cells could radically change health and medicine

Cell biology is a world of constant motion and hidden...

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The Vatnajökull ice cap in southeast Iceland Today&#8217;s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features a Copernicus Sentinel-2 view of the Vatnajökull ice cap in southeast Iceland.
Vatnajökull is the biggest glacier in Europe, covering an area of more than 3,200 square miles. 
The ice cap has about 30 outlet glaciers, many of which are shrinking as a result of rising temperatures. One of these glaciers, Vatnajökull, is positioned over some of the most active volcanoes in Iceland such as Bárðarbunga and Grímsvötn.
On the southern side of Vatnajökull, the Jökulsárlón glacial lake has grown to become Iceland&#8217;s deepest lake. Because it connects with the ocean, the lake contains both seawater and freshwater. 
The island was governed as an independent commonwealth under the Althing, therefore being  of the world&#8217;s oldest functioning legislative assemblies. Also there is  a period of civil strife, Iceland acceded to Norwegian rule in the 13th century. The establishment of the Kalmar Union in 1397 united the kingdoms of Norway, Denmark, and Sweden. Iceland also followed Norway&#8217;s integration into that union, coming under Danish rule after Sweden&#8217;s secession from the union in 1523.  The capital and largest city is Reykjavík
Video Credit: ESA  
&#8211;&#8212;
By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The Vatnajökull ice cap in southeast Iceland

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