Today's Image of the Day from the European Space Agency features the barred spiral galaxy NGC 3783, which is located about 130 million light-years away in the constellation Centaurus. 



NGC 3783 is also the most prominent of a galaxy group (by the same name) that contains 47 galaxies.&nbsp;



<h2 class="wp-block-heading" id="h-what-are-galaxy-groups">What are galaxy groups?</h2>



“Like galaxy clusters, galaxy groups are aggregates of gravitationally bound galaxies. Galaxy groups, however, are less massive and contain fewer members than <a href="https://www.earth.com/news/titanic-galaxy-cluster-collision-defies-all-current-understanding-of-the-universe/" target="_blank" rel="noreferrer noopener">galaxy clusters</a> do: where galaxy clusters can contain hundreds or even thousands of constituent galaxies, galaxy groups do not typically include more than 50,” noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



“The Milky Way is actually part of a galaxy group, known as the Local Group, which contains two other large galaxies (Andromeda and the Triangulum galaxy), as well as several dozen satellite and dwarf galaxies.”



<h2 class="wp-block-heading" id="h-a-blue-giant-star">A blue giant star</h2>



The bright object that appears to the right of the galaxy is the star HD 101274. “The perspective in this image makes the star and the galaxy look like close companions, but this is an illusion. HD 101274 lies only about 1,530 light-years from Earth, meaning it is about 85 thousand times closer than NGC 3783,” explained ESA.&nbsp;



The star is part of the NGC 3766 cluster, sometimes referred to as the Pearl Cluster, which is known for its richness in bright stars and its relatively young age.



Characterized by its high temperature and luminosity, HD 101274 is categorized as a blue giant star.



<h2 class="wp-block-heading" id="h-significance-of-blue-giants">Significance of blue giants</h2>



Blue giants are massive stars that have left the main sequence phase of stellar evolution and are burning helium or heavier elements in their cores. These stars are known for their short lifespans relative to smaller stars due to their rapid consumption of nuclear fuel.



<a href="https://www.earth.com/news/dark-stars-scientists-discover-a-new-type-of-star-powered-by-dark-matter/" target="_blank" rel="noreferrer noopener">Stars</a> like HD 101274 are important for astronomers because they help in studying the properties of stellar populations in clusters and the dynamics of stellar evolution in different environments. 



Observations of blue giant stars can provide valuable insights into the characteristics of their atmospheres, internal structures, and the processes occurring within and around them.



<h2 class="wp-block-heading" id="h-active-galactic-nucleus-of-ngc-3783">Active galactic nucleus of NGC 3783</h2>



One of the most interesting aspects of NGC 3783 is that it harbors an active galactic nucleus. This means that its central region is exceptionally luminous, likely due to the presence of a supermassive black hole. 



The black hole is actively accreting material, which emits a substantial amount of radiation as it spirals inward and heats up.



The galaxy has been studied extensively in the ultraviolet and X-ray light spectra to understand better the properties of the accretion disk around the black hole and the complex dynamics of the material surrounding it. 



These studies are crucial for understanding the physics of active galactic nuclei and the role they play in <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">galaxy evolution</a>.



According to ESA, NGC 3783 is a&nbsp;Type I Seyfert galaxy. “In this image it is recorded by Hubble in incredible detail, from its glowing central bar to its narrow, winding arms and the dust threaded through them, thanks to five separate images taken in different wavelengths of light," noted ESA.



“In fact, the galactic center is bright enough to Hubble that it exhibits diffraction spikes, normally only seen on stars such as HD 101274.”



<h2 class="wp-block-heading" id="h-massive-collection-of-galaxy-clusters">Massive collection of galaxy clusters</h2>



The NGC 3783 group is part of the larger Hydra-Centaurus Supercluster, which itself is a massive collection of <a href="https://www.earth.com/news/shapes-of-one-million-galaxies-hint-at-the-universes-origins/" target="_blank" rel="noreferrer noopener">galaxies</a> and galaxy clusters located primarily in the constellations of Hydra and Centaurus.



The NGC 3783 group consists of several galaxies that are gravitationally bound and interact with each other. These interactions can influence the galaxies' evolution through mechanisms like tidal forces and merger events, which can trigger star formation, fuel central black holes, and reshape the galaxies' structures.



Studying the NGC 3783 group helps astronomers understand how <a href="https://www.earth.com/news/ceers-2112-ancient-galaxy-looks-strikingly-similar-to-ours/" target="_blank" rel="noreferrer noopener">galaxies</a> evolve together in a common gravitational environment, offering insights into the dynamics and evolution of structures on cosmic scales.



Image Credit: ESA/Hubble &amp; NASA



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Luminous spiral galaxy and a blue giant star

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

Today's Image of the Day from the European Space Agency features the star-forming region NGC 604. The nebula is located 2.73 million light-years away from Earth in the Triangulum Galaxy (M33). 



By studying regions like NGC 604, astronomers can gain insights into the complex interactions between stars and the interstellar medium, as well as the conditions that lead to the birth of stars. 



This, in turn, helps us understand the evolution of <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">galaxies</a> and the universe as a whole.



<h2 class="wp-block-heading" id="h-massive-stars-of-ngc-604">Massive stars of NGC 604</h2>



"Sheltered among NGC 604’s dusty envelopes of gas are more than 200 of the hottest, most massive kinds of stars, all in the early stages of their lives," said <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



"These types of stars are known as B-types and O-types, the latter of which can be more than 100 times the mass of our own Sun. It’s quite rare to find this concentration of them in the nearby universe. In fact, there’s no similar region within our own Milky Way galaxy."



According to ESA, this concentration of massive stars, combined with its relatively close distance, means that NGC 604 gives astronomers an opportunity to study these objects at a fascinating time early in their life.



<h2 class="wp-block-heading" id="h-gigantic-region-of-ionized-hydrogen">Gigantic region of ionized hydrogen</h2>



NGC 604 is one of the largest known regions of ionized hydrogen, also known as an H II region. This nebula is significantly larger than the Orion Nebula, which is one of the most well-known H II regions in our own <a href="https://www.earth.com/news/large-amount-of-dark-matter-may-be-missing-from-the-milky-way/" target="_blank" rel="noreferrer noopener">Milky Way galaxy</a>.&nbsp;



NGC 604 spans about 1,500 light-years across, making it one of the largest H II regions in the Local Group of galaxies. This group includes the Milky Way, the Andromeda Galaxy, and about 54 other smaller galaxies.&nbsp;



<h2 class="wp-block-heading" id="h-ngc-604-starburst-phenomenon">NGC 604 starburst phenomenon </h2>



Within NGC 604, there are hundreds of young, hot, massive <a href="https://www.earth.com/news/stars-at-the-edge-of-our-milky-way-galaxy-travel-more-slowly/" target="_blank" rel="noreferrer noopener">stars</a>. These stars have ionized the surrounding gas, causing it to glow and creating the nebula. 



The region is a prime example of a starburst phenomenon, where stars form at a much higher rate than in typical galactic conditions.



“The bright orange streaks in this image signify the presence of carbon-based molecules known as polycyclic aromatic hydrocarbons, or PAHs," explained ESA.



"As you travel further from the immediate cavities of dust where the star is forming, the deeper red signifies molecular hydrogen. This cooler gas is a prime environment for star formation. Ionized hydrogen from ultraviolet radiation appears as a white and blue ghostly glow."



<h2 class="wp-block-heading" id="h-more-about-star-formation">More about star formation </h2>



Star formation is crucial for the evolution of galaxies and the synthesis of heavy elements. In the cores of stars, elements heavier than helium are created.



The elements are spread throughout the <a href="https://www.earth.com/news/ancient-stars-shakti-shiva-shaped-milky-way-galaxy/" target="_blank" rel="noreferrer noopener">galaxy</a> when stars reach the end of their lives and expel their material - either gently through winds or violently via supernova explosions. 



This enriching process allows for the formation of new stars and planets, and ultimately, the potential for life.



<h3 class="wp-block-heading">Cloud collapse</h3>



The process begins when part of a molecular cloud becomes unstable and starts to collapse under its own gravity. This can be triggered by events like shock waves from nearby <a href="https://www.earth.com/news/supernova-explosions-could-damage-distant-planets/" target="_blank" rel="noreferrer noopener">supernovae</a>, galactic collisions, or the influence of other massive stars.



<h3 class="wp-block-heading">Formation of a protostar</h3>



As the cloud collapses, it fragments into smaller clumps. Each clump will eventually form one or more stars. 



The material within these clumps continues to fall inward, heating up as it does so, eventually forming a warm core called a protostar. At this stage, the protostar is not yet hot enough for nuclear fusion (the process that powers stars) to occur.



<h3 class="wp-block-heading">Accretion disk</h3>



Around the protostar, material from the surrounding cloud continues to fall inward, forming a rotating disk. This material slowly accretes onto the protostar, increasing its mass.



<h3 class="wp-block-heading">Nuclear fusion begins</h3>



Once the core of the protostar reaches a high enough temperature and pressure, hydrogen atoms begin to fuse into helium, releasing energy in the process. This marks the transition from a protostar to a main sequence star, like our sun.



<h3 class="wp-block-heading">Main sequence and beyond</h3>



The star will spend the majority of its life in the main sequence stage, where it balances the gravitational forces trying to collapse it and the outward pressure from nuclear fusion. 



Eventually, the star will exhaust its hydrogen fuel. Its subsequent evolution will depend on its initial mass, leading to various end stages such as red giants, supernovae, neutron stars, or black holes.



Image Credit: NASA/ESA/CSA James Webb Space Telescope



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Young, massive stars in the Triangulum Galaxy

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 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

For three long years, Luna called the theme park home. But, one day, several new visitors came to see her. While she had learned to ignore the children surrounding her cage, these people were different. Photo Credit: Public Radio International

Strange Visitors

In the United States, about 32 percent of adults now have at least one tattoo. Despite their widespread presence across all walks of life, tattoos still trigger snap judgments about an individual's personality, values, or lifestyle.



A new study from <a href="https://msu.edu/" target="_blank" rel="noreferrer noopener">Michigan State University</a> questions those snap judgments. The study revealed that observers frequently misinterpret personality traits based on tattoo content, style, and appearance



<h2 class="wp-block-heading" id="h-tattoos-are-common-but-still-judged">Tattoos are common but still judged</h2>



Ink has become a common part of daily life, from teachers' forearms to politicians' ankles. <a href="https://www.pewresearch.org/wp-content/uploads/2023/08/SR_23.08.15_Tattoos_topline.pdf" target="_blank" rel="noreferrer noopener">Eight in ten Americans</a> say their communities are now more accepting of body art compared to 20 years ago.



Even so, a deep undercurrent of <a href="https://pubmed.ncbi.nlm.nih.gov/28934022/" target="_blank" rel="noreferrer noopener">tattoo stigma</a> survives. Earlier research found that tattooed adults were viewed as more deviant, less conscientious, and more promiscuous than their un‑inked peers. 



Children as young as six linked tattoos to delinquent behavior in a classic 2000 <a href="https://bpspsychub.onlinelibrary.wiley.com/doi/abs/10.1348/135532500168065" target="_blank" rel="noreferrer noopener">study</a> by Durkin and Houghton.



Studies also show <a href="https://www.psychologytoday.com/ca/blog/head-games/201809/are-people-with-tattoos-stigmatized" target="_blank" rel="noreferrer noopener">gender effects</a>. Women with visible ink are often judged more harshly than men, especially in hospitality and healthcare settings.



Modern workplaces try to project inclusivity, yet hiring managers still admit that visible <a href="https://www.earth.com/news/wireless-e-tattoo-detects-when-your-brain-gets-overloaded/">ink</a> can hurt an applicant. Simmering bias fuels a market for makeup that covers sleeves during interviews.



<h2 class="wp-block-heading" id="h-tattoo-and-personality-links">Tattoo and personality links</h2>



William Chopik and Brooke Soulliere, both psychologists at Michigan State University, photographed 375 tattoos from 274 volunteers. The volunteers completed a full <a href="https://www.truity.com/test/big-five-personality-test" target="_blank" rel="noreferrer noopener">Big Five personality traits</a> inventory before rolling down their sleeves.



“We found that people did tend to rate the personalities of tattooed people consistently,” explained Chopik. 



A separate panel looked only at each image and guessed the wearer’s personality. Observers saw the ink but not the person’s face, clothing, or setting. That design isolated the tattoo as the single visible cue, mimicking quick judgments made on a sidewalk or social feed.



Soulliere added that the study covered 18 features, from size to color to placement. Testing each cue against personality scores allowed the team to see which visual <a href="https://www.earth.com/news/tattoos-increase-the-risk-of-developing-lymphoma/">hints</a>, if any, were worth trusting.



<h2 class="wp-block-heading" id="h-tattoos-rarely-show-true-personality">Tattoos rarely show true personality</h2>



The results showed agreement among raters, meaning most viewers made the same assumptions. Agreement, however, is not accuracy. 



Traits such as agreeableness, conscientiousness, extraversion, and neuroticism were wrongly assigned. The raters’ confidence did not rescue their guesses.



Psychologists describe this pattern with the <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC9103609/" target="_blank" rel="noreferrer noopener">lens model</a>, which says people read surface cues to infer hidden qualities. Tattoos act as one such lens, but the view they provide can be cloudy. Studies over the past decade linked skulls, guns, or prison motifs to criminal stereotypes among jurors.



Sticker‑covered <a href="https://www.sciencedirect.com/science/article/abs/pii/S0092656621001239" target="_blank" rel="noreferrer noopener">laptops</a> tell a parallel story. Raters accurately judged an <a href="https://www.earth.com/news/tattoo-ink-travels-through-the-body-and-may-cause-long-term-risks/">owner</a>’s openness and extraversion by glancing at personalized decals.



<h2 class="wp-block-heading" id="h-tattoo-meaning-and-personality-often-clash">Tattoo meaning and personality often clash</h2>



Getting tattooed often involves what psychologists call identity claims. A self‑directed claim might memorialize a child’s birthdate, while an other‑directed claim signals allegiance to a military unit or sports team. 



The problem arises when outsiders guess the message without context. A snake entwined with roses could honor recovery from illness, yet many will see danger or rebellion.



Anthropologists note that body art has held meaning across cultures for millennia, from Polynesian rite‑of‑passage marks to Japanese irezumi. Western viewers unfamiliar with these traditions may project their own narratives instead.



Social media accelerates the misreading. A single viral image can lock a stranger into a public persona built on nothing more than a wrist tattoo glimpsed under café lights.



<h2 class="wp-block-heading" id="h-tattoos-link-to-openness-only">Tattoos link to openness only</h2>



The Michigan State team uncovered one sliver of accuracy. Viewers who saw a tattoo described as quirky, goofy, or simply odd tended to peg the owner as high in openness to experience. 



“When people see a wacky or goofy tattoo, they assume that person is open to experience, and they’re correct about it,” noted Soulliere.



Openness tracks curiosity, creativity, and a hunger for novelty. A full sleeve of abstract color or a playful cartoon can hint at those traits more faithfully than a skull wrapped around a dagger. 



Many open‑minded folks choose minimalist ink, and some conventional thinkers pick bold designs on a dare.



Researchers suspect the accuracy stems from selection rather than signal. People high in openness may be drawn to unusual images, so the art style predicts the trait.



<h2 class="wp-block-heading" id="h-tattoo-and-personality-bias-affects-life">Tattoo and personality bias affects life</h2>



Snap judgments about tattoos happen in classrooms, clinics, courtrooms, and dating apps. Mistaking agreeableness or conscientiousness can nudge decisions on trust, hiring, or even sentencing. 



Bias also works inward. People who know the stereotypes may edit their ink choices to avoid certain images, limiting self‑expression in subtle ways.



Future research may test whether adding context - such as the story behind a tattoo - improves accuracy. For now, experts urge caution before reading too much into a rose, a dragon, or a pop‑culture tribute.



<h2 class="wp-block-heading" id="h-reducing-tattoo-and-personality-bias">Reducing tattoo and personality bias</h2>



The first step is awareness, and studies like this one give people an evidence‑based reason to pause before leaping to conclusions. 



Training programs in customer service and law enforcement already include modules on implicit bias, but tattoos rarely appear in those slides.



Organizations could add quick reminders that body art alone predicts little besides a taste for ink. A supervisor who knows that fact is less likely to equate a forearm phoenix with poor reliability. 



Small actions add up. Asking an employee about their new tattoo, rather than assuming its meaning, turns a potential bias trap into a conversation starter.



The study is published in the <a href="https://www.sciencedirect.com/science/article/abs/pii/S0092656625000613?via%3Dihub" target="_blank" rel="noreferrer noopener">Journal of Research in Personality</a>.



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Tattoos lead to mistaken assumptions about personality and values

In the United States, about 32 percent of adults now...

Tiny bits of plastic no wider than a human hair have turned up in some unexpected places, including the human bloodstream. 



Now, data presented at the European Society of Human Reproduction and Embryology meeting shows that these <a href="https://www.earth.com/news/microplastics-spread-deep-into-the-ocean-far-below-the-surface/">fragments</a> have breached the fluids that surround eggs and travel with sperm.



The research team led by Dr. Emilio Gómez‑Sánchez of Next Fertility Murcia in Spain scanned <a href="https://www.sciencedirect.com/topics/biochemistry-genetics-and-molecular-biology/follicular-fluid" target="_blank" rel="noreferrer noopener">follicular fluid</a> from 29 women and seminal fluid from 22 men.



The experts found microplastics in 69 percent of the women and 55 percent of the men they studied. According to Dr. Gómez‑Sánchez, the team was surprised to find that the particles were so widespread.



<h2 class="wp-block-heading" id="h-plastics-in-human-reproductive-fluids">Plastics in human reproductive fluids</h2>



The study detected polymers such as <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/polytetrafluoroethylene" target="_blank" rel="noreferrer noopener">polytetrafluoroethylene</a> and <a href="https://adrecoplastics.co.uk/polypropylene-uses/" target="_blank" rel="noreferrer noopener">polypropylene</a>, materials better known for slick frying pans and food packaging. Seeing them next to human eggs turns a theoretical hazard into a measurable one.



Back in 2021, Italian obstetricians spotted twelve plastic fragments in every placenta they examined, confirming that particles smaller than five millimeters can cross the <a href="https://pubmed.ncbi.nlm.nih.gov/33395930/" target="_blank" rel="noreferrer noopener">maternal‑fetal boundary</a>.



Similarly sized particles have been uncovered deep in <a href="https://pubmed.ncbi.nlm.nih.gov/35364151/" target="_blank" rel="noreferrer noopener">lung tissue</a> removed during surgery, proving that inhalation is a realistic delivery route for <a href="https://www.earth.com/news/simple-way-to-remove-microplastics-from-tap-water-home-faucet/">plastic</a> dust.



Researchers in the Netherlands have even measured plastic mass circulating in human blood samples, an <a href="https://pubmed.ncbi.nlm.nih.gov/35367073/" target="_blank" rel="noreferrer noopener">observation</a> that explains how fragments migrate to distant tissues.



<h2 class="wp-block-heading" id="h-how-plastics-enter-the-human-body">How plastics enter the human body</h2>



Most people take in <a href="https://www.earth.com/news/microplastics-in-human-brains-may-affect-mental-health/">plastic</a> flecks by eating, drinking, or breathing, because everyday products shed invisible dust whenever they are heated, abraded, or exposed to sunlight. 



Once swallowed or inhaled, particles small enough can slip through the gut wall or the thin air‑blood membrane in the lungs.



Animal studies suggest that fragments under one micrometer can enter cells directly, whereas larger shards get trapped in tissue and spark local irritation. Either way, they bypass the body’s usual waste filters.



Laboratory work on mice shows that digestive uptake rises when <a href="https://www.earth.com/news/airborne-microplastics-where-they-come-from-and-where-they-go/">microplastics</a> hitchhike on fats, a detail that matters for fertility research because reproductive hormones ride on similar lipid highways. 



The overlap raises worry that plastics may act as endocrine mimics or carriers for other chemicals.



Dr. Gómez‑Sánchez’s team avoided laboratory contamination by collecting every human sample in glass vials and verifying the absence of background plastic. This means the polymers they found were genuine residents, not stray lab dust.



<h2 class="wp-block-heading" id="h-plastic-harms-fertility">Plastic harms fertility</h2>



Mice exposed to polystyrene fragments shed sperm with damaged DNA and sluggish movement, effects traced to <a href="https://pubmed.ncbi.nlm.nih.gov/31896473/" target="_blank" rel="noreferrer noopener">oxidative stress</a> that overwhelms antioxidant defenses.



Separate <a href="https://pubmed.ncbi.nlm.nih.gov/36948006/" target="_blank" rel="noreferrer noopener">work</a> on rodent Leydig cells shows shriveled mitochondria after nanoplastic exposure, which throttles testosterone production and shrinks litter sizes.



Reviews published in 2024 concluded that microplastics can disrupt the <a href="https://pubmed.ncbi.nlm.nih.gov/38750730/" target="_blank" rel="noreferrer noopener">hypothalamic‑pituitary‑gonadal axis</a>, leading to hormonal imbalances and faulty egg maturation.



Because human oocytes develop over months, chronic exposure could matter more than a short spike. That makes the repeated detection of PTFE in both eggs and sperm especially noteworthy.



<h2 class="wp-block-heading" id="h-plastic-levels-in-eggs-and-sperm">Plastic levels in eggs and sperm</h2>



In the current data set, PTFE appeared in 31 percent of sampled egg fluid and 41 percent of semen. PP ranked second among women and <a href="https://www.chemicalsafetyfacts.org/chemicals/polystyrene/" target="_blank" rel="noreferrer noopener">polystyrene</a> second among men, with <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/polyethylene-terephthalate" target="_blank" rel="noreferrer noopener">polyethylene terephthalate</a> also present but in smaller numbers.



Annual plastic output has climbed from under two million tons in 1950 to about 460 million in 2019, a 230‑fold jump documented by the <a href="https://pubmed.ncbi.nlm.nih.gov/36969097/" target="_blank" rel="noreferrer noopener">Minderoo‑Monaco Commission on Plastics and Human Health</a>.



Each uptick in production increases litter, weathering, and fragment release, tightening the feedback loop between plastics and people. Reproductive cells, delicate by design, stand on the front line.



Gómez‑Sánchez reported that most reproductive samples contained only one or two plastic particles, amounts considered low compared with overall debris in the fluids. Yet fertility specialists note that even trace metals can derail embryo development, so particle counts alone may not predict risk.



<h2 class="wp-block-heading" id="h-human-fertility-research-must-include-plastics">Human fertility research must include plastics</h2>



“They should be considered an additional argument in favor of avoiding the generalized use of plastics in our daily lives,” said Professor Carlos Calhaz‑Jorge of the University of Lisbon. He also noted that further research is needed to prove causation.



The research team will now study hundreds of patients and link particle loads to embryo quality during <a href="https://my.clevelandclinic.org/health/treatments/22457-ivf" target="_blank" rel="noreferrer noopener">in vitro fertilization cycles</a>. Those correlations could supply the first direct human evidence beyond laboratory rodents.



They plan lifestyle questionnaires to test whether habits such as heavy bottled‑water use or microwaving food in plastic correlate with higher particle counts. The approach could convert abstract exposure theory into personal advice.



“Microplastics are just one variable in a complex equation,” said Dr. Gómez‑Sánchez. He urges moderation of plastic use rather than alarm. 



<h2 class="wp-block-heading" id="h-simple-habits-to-lower-exposure">Simple habits to lower exposure</h2>



Switching from plastic bottles to glass or stainless steel lowers ingestion because heat and time no longer leach particles from container walls. Replacing scratched nonstick pans can cut PTFE flakes in the diet.



Researchers advise skipping plastic cutting boards and using ceramic or bamboo instead, because knife action liberates shavings that cling to food. Letting take‑out cool before transferring it from polystyrene boxes also helps.



Air purifiers with HEPA filters capture airborne fibers shed by synthetic textiles, a step especially useful for nurseries. Regular vacuuming with a sealed system keeps particles from resuspending.



These tweaks are not foolproof, yet they come with side benefits like removing chemical additives that ride on plastic dust. They buy time while science sorts out the clinical stakes.



<h2 class="wp-block-heading" id="h-efforts-to-cut-human-plastics-pollution">Efforts to cut human plastics pollution</h2>



Public‑health researchers argue that personal choices alone cannot outrun a supply chain making more than a billion pounds of new plastic every day. 



Negotiators at the United Nations are hammering out a global treaty that could cap production and streamline recycling.



<a href="https://www.bc.edu/bc-web/schools/morrissey/departments/biology/people/faculty-directory/Phil-Landrigan.html" target="_blank" rel="noreferrer noopener">Dr. Philip Landrigan</a> of Boston College calls the treaty a once‑in‑a‑generation chance to protect human health, because curbing output remains the only sure way to slow microplastic fallout. He points to the emerging fertility data as evidence that time is short.



Whether lawmakers act or not, the science of sub‑visible plastic is moving fast thanks to sharper imaging tools and nanomechanical sensors. Studies that once took months now finish in days, filling the literature with fresh clues.



Every new dataset sharpens the same picture: plastics weather into dust, the dust goes everywhere, and living tissue keeps no closed doors. Eggs and sperm, it turns out, are no exception.



The study is published in the journal <a href="https://academic.oup.com/humrep#google_vignette" target="_blank" rel="noreferrer noopener">Human Reproduction</a>.



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Tiny plastic particles found in human egg and sperm fluids

Tiny bits of plastic no wider than a human hair...

The sea spider, those spindly marine oddities that seem composed almost entirely of legs and claws, just given up their genetic secrets.



An international effort led by the <a href="https://www.univie.ac.at/en/">University of Vienna</a> and the <a href="https://www.wisc.edu/">University of Wisconsin–Madison</a> has delivered the first chromosome-level genome for Pycnogonum litorale, a species common in North Atlantic tide pools.



Stretching across 57 pseudo-chromosomes and paired with extensive developmental transcriptomes, the assembly offers an unprecedented look at how an arthropod can evolve such an extreme body plan. This includes a nearly vanishing abdomen and internal organs that spill far into its limbs.



<h2 class="wp-block-heading" id="h-mapping-the-sea-spider-genome">Mapping the sea spider genome</h2>



To achieve a genome this contiguous, the team combined long-read sequencing with Hi-C proximity data. Long reads captured tens of thousands of DNA bases at a stretch. This helped bridge the repetitive regions that routinely break short-read assemblies.



Hi-C, which measures how DNA folds inside the nucleus, then provided a “scaffolding” map that placed those long contigs into chromosomal order.



“The genomes of many non-canonical laboratory organisms are challenging to assemble, and Pycnogonum is no exception," said first author Nikolaos Papadopoulos, a zoologist at the University of Vienna. 



"Only the combination of modern high-throughput data sources made a high-quality genome possible. This can now serve as a stepping stone for further research.”



Because <a href="https://www.earth.com/news/surprising-breeding-behaviors-of-giant-sea-spiders-revealed/">sea spiders</a> are not standard lab animals, researchers collected specimens by hand, often prying them from kelp during low tide. They then rushed them back to the lab for nucleic acid extraction.



The payoff is a reference genome that joins spider, <a href="https://www.earth.com/news/fossil-reveals-the-first-ancestors-of-scorpions-and-spiders/">scorpion</a>, mite, and horseshoe crab assemblies on public databases. Yet it lacks the duplications that mark other arachnid genomes, making it a vital baseline for evolutionary comparisons.



<h2 class="wp-block-heading" id="h-vanished-gene-vanished-abdomen">Vanished gene, vanished abdomen</h2>



The analysis focused on Hox genes, key developmental regulators shared by animals from fruit flies to humans. One gene turned up missing: abdominal-A (abd-A).



In most arthropods, abd-A helps establish the rear-body segments that carry guts and reproductive organs. Sea spiders, with their virtually absent abdomens, appear to have dispensed with both the physical structure and its genetic architect.



“In arthropods, Hox genes play a central role in the correct specification of the different body segments, explained co-author Andreas Wanninger, who co-led the Vienna team. "In many other animal groups they are essential ‘master controllers’ during body plan development.” 



The disappearance of abd-A mirrors patterns seen in <a href="https://www.earth.com/news/how-mites-survived-without-sex-for-millions-of-years/">mites</a> and barnacles, two other arthropod groups that have independently shrunk or lost their hind segments.



<h2 class="wp-block-heading" id="h-sea-spiders-skipped-genome-doubling">Sea spiders skipped genome doubling</h2>



Spiders and scorpions carry extra copies of almost every gene, relics of an ancient whole-genome duplication that likely fueled innovations such as silk glands and complex venom cocktails.



P. litorale shows no sign of that event. Because sea spiders sit at the very base of the chelicerate lineage, the simplest explanation is that the duplication occurred later. It likely arose within the spider-scorpion branch, rather than in the common ancestor of all chelicerates.



That finding reshapes timelines for when gene families expanded and may help researchers pinpoint which duplications underlie spider-specific traits.



<h2 class="wp-block-heading" id="h-tools-for-growth-and-repair">Tools for growth and repair</h2>



Beyond raw sequence, the consortium generated RNA profiles from embryos and juveniles, capturing when each gene flicks on and off as new body segments form.



Those developmental datasets make the sea spider a promising model for studies of ancestral arthropod development, limb regeneration, and physiological resilience in cold, nutrient-poor seas.



Georg Brenneis, an expert in arthropod development at the University of Vienna, is a senior author of the study.



“From an evolutionary developmental perspective, sea spiders are very interesting: their mode of development may be ancestral for arthropods, but at the same time they boast multiple body plan innovations unique to themselves. Beyond this, they also possess remarkable regenerative abilities.” 



“Now that we have the genome and comprehensive datasets on gene activities during development, we can systematically study all of these aspects on the molecular level,” he said.



<h2 class="wp-block-heading" id="h-editing-limbs-and-trunk">Editing limbs and trunk</h2>



With <a href="https://www.earth.com/news/crispr-used-to-remove-extra-chromosomes-in-down-syndrome-and-restore-cell-function/">CRISPR</a> editing becoming feasible in marine invertebrates, investigators can now ask how the remaining sea spider Hox genes choreograph eight elongated walking legs and a tubular trunk. They can also explore how the animals quickly regrow lost appendages.



Comparative physiologists might search the genome for stress-response genes that let sea spiders thrive in icy fjords, while ecological genomics teams could examine how gene flow operates across their wide geographic ranges.



<h2 class="wp-block-heading" id="h-tracing-ancient-sea-spider-cousins">Tracing ancient sea spider cousins</h2>



Without the duplication, shared sea spider genes likely existed as single copies in the last common chelicerate ancestor.



Aligning those sequences will clarify where new venom toxins arose, when silk machinery evolved, and how immune genes diversified.



The genome also lets scientists investigate regulatory DNA - enhancers, promoters, and non-coding RNAs. These elements rewired a conventional arthropod blueprint into the minimalist sea spider form.



<h2 class="wp-block-heading" id="h-expanding-the-genomic-catalog">Expanding the genomic catalog</h2>



The authors envision expanding the catalog to additional sea spider species to test whether abd-A loss is universal. They also aim to map gains and losses of other developmental genes across the group’s 1,300 known species.



Such work could uncover genetic shortcuts to extreme morphological change - insights that extend far beyond any single marine arthropod.



For now, the P. litorale genome stands as a milestone: the first high-quality reference for the world’s most enigmatic chelicerates. It’s also a reminder that even life’s strangest branches follow molecular rules that genomics can finally reveal.



The study is published in the journal <a href="https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-025-02276-x">BMC Biology</a>.



Image Credit: Richard Lord/ <a href="https://creativecommons.org/licenses/by-nc-sa/4.0/legalcode.en">CC BY-NC-SA 4.0</a>



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All legs, no guts: Sea spider genome stuns scientists

The sea spider, those spindly marine oddities that seem composed...

High in northern Peru, three frogs no bigger than a thumbprint have stepped out of anonymity and into the scientific spotlight. Their world is a maze of wet cliffs, dripping bromeliads, and wind‑scoured ridges where moss carpets the rocks.



“They’re <a href="https://www.earth.com/news/world-frog-day-2025-protecting-natures-tiny-guardians/">small</a> and unassuming, but these frogs are powerful reminders of how much we still don’t know about the Andes,” said Germán Chávez of the Center for Ornithology and Biodiversity (<a href="https://corbidi.org/">CORBIDI</a>). 



Chávez and his colleagues trekked those ridges between 2021 and 2024, often in freezing rain, to reach calling sites above 9,000 feet.&nbsp;



<h2 class="wp-block-heading" id="h-mountains-support-unique-frog-species">Mountains support unique frog species</h2>



The <a href="https://blog.pensoft.net/2025/06/27/hidden-gems-in-the-mist-three-new-frog-species-uncovered-in-northern-peru/cordillera-de-huancabamba-1/" target="_blank" rel="noreferrer noopener">Cordillera de Huancabamba</a> forms a natural break in the Andes, splitting watersheds and isolating species. 



Ecologists classify the region as a <a href="https://www.cepf.net/sites/default/files/tropicalandes_techsummary.pdf" target="_blank" rel="noreferrer noopener">biodiversity hotspot</a>, one of only thirty‑five on Earth where extraordinary endemism collides with severe habitat loss.



"The Cordillera de Huancabamba is not just a remote range - it's a living archive of biodiversity and cultural legacy," said Wilmar Aznaran. "And we've barely scratched the surface."



Isolation breeds novelty, and novelty fills the genus Pristimantis. With 619 described species, Pristimantis is now the most diverse <a href="https://www.earth.com/news/whistling-forest-frogs-recently-discovered-may-be-wiped-out-before-we-learn-about-them/">amphibian</a> genus on the planet.



The new frogs, Pristimantis chinguelas, P. nunezcortezi, and P. yonke, occupy different niches along the same ridge. One clings to cliff faces, one prowls leaf litter beside clear streams, and the smallest tucks itself deep inside tank bromeliads.



<h2 class="wp-block-heading" id="h-confirming-the-new-species">Confirming the new species</h2>



Night surveys began after dusk, when temperatures hovered near 50 °F and fog erased headlamp beams. Team members listened for faint “peep” notes that barely rose above dripping leaves. 



Finding a caller did not end the chase. Each frog had to be photographed, swabbed for DNA, measured, and released without harming delicate skin.



Back in Lima, the researchers compared mitochondrial 16S sequences. Genetic distances exceeded the three‑percent threshold herpetologists often use to flag separate <a href="https://www.earth.com/news/missing-frog-species-alsodes-vittatus-resurfaces-after-130-years/">species</a>, clinching the case for formal description.



<h2 class="wp-block-heading" id="h-many-amphibians-are-poorly-studied">Many amphibians are poorly studied </h2>



All three newcomers enter the IUCN books as <a href="https://www.thebhs.org/publications/the-herpetological-bulletin/issue-number-169-autumn-2024/4079-03-how-many-data-deficient-amphibians-are-threatened-iucn-red-list-assessments-for-amphibian-species-previously-classed-as-data-deficient" target="_blank" rel="noreferrer noopener">Data Deficient</a>, meaning scientists lack enough information to judge extinction risk. 



The label sounds neutral, yet recent reassessments show that roughly half of amphibians that start as Data Deficient later prove threatened.



Formal names unlock funding and legal tools that nameless creatures rarely receive. Conservation plans, environmental‑impact statements, and protected‑area budgets almost always hinge on a taxon’s standing in recognized databases.



<h2 class="wp-block-heading" id="h-indicators-of-climate-shifts">Indicators of climate shifts</h2>



The Cordillera de Huancabamba isn't just a biological goldmine, it’s wrapped in layers of folklore. In nearby villages, frogs are often seen as signs of rain or omens tied to agriculture and spiritual beliefs.



This cultural lens makes local communities key allies for conservation. When researchers name <a href="https://www.earth.com/news/frogs-lead-the-way-in-developing-new-antibiotics/">species</a> after regional icons or traditions, like P. yonke, they honor local identity and encourage stewardship.



Unlike most frogs, species in the <a href="https://www.inaturalist.org/taxa/64811-Pristimantis" target="_blank" rel="noreferrer noopener">Pristimantis genus</a> bypass the tadpole stage entirely. They hatch from eggs as fully formed froglets, ready to climb, hop, and call without ever entering water.



This reproductive shortcut allows them to thrive in places where standing water is rare or seasonal. It also makes them sensitive indicators of climate shifts and microhabitat changes in mountain ecosystems.



<h2 class="wp-block-heading" id="h-frog-species-in-fire-prone-habitats">Frog species in fire-prone habitats</h2>



Each frog occupies an area smaller than four square miles, hemmed in by crop fields and fire scars. Peru recorded about 10,400 wildfires in 2024, more than double its previous record, burning grasslands and cloud‑forest edges alike.



P. chinguelas calls from a road‑cut cliff where charred bamboo still smells of smoke. P. nunezcortezi shares a single stream corridor that now borders new potato plots.



P. yonke lives higher, inside bromeliads at roughly 9,800 feet, in what locals call the <a href="https://lacgeo.com/northern-andean-paramo" target="_blank" rel="noreferrer noopener">páramo</a>, a chilly grassland‑wetland mosaic perched above the treeline. 



Páramo vegetation stores water like a sponge, so every lost bromeliad weakens both the frogs and the human communities farther down‑slope.



“Exploring this area is more than fieldwork - it’s an immersion into wilderness, culture, and resilience,” said Karen Victoriano‑Cigüeñas.&nbsp;



"Many of these mountain&nbsp;ridges&nbsp;are isolated, with no roads and extreme terrain," noted Ivan Wong. "The weather shifts within minutes, and the steep cliffs make every step a challenge. It's no wonder so few scientists have worked here before. But that's exactly why there's still so much to find."



<h2 class="wp-block-heading" id="h-protecting-the-new-frog-species">Protecting the new frog species </h2>



No one has recorded the breeding calls of P. nunezcortezi or P. yonke, so females remain unverified. Diet, predators, and lifespan also remain mysteries for all three species.



Future expeditions will test whether the frogs persist on neighboring ridges or whether each ridge hosts its own micro‑endemic. 



Acoustic monitors and <a href="https://royalsocietypublishing.org/doi/10.1098/rspb.2019.2353" target="_blank" rel="noreferrer noopener">eDNA traps</a> could reveal silent populations hiding in moss tunnels or bromeliad tanks beyond the reach of hikers.



For now, the frogs depend on local goodwill. Community fire patrols, low‑impact grazing, and small protected micro‑reserves can buy time while researchers gather the missing data.



The study is published in the journal <a href="https://evolsyst.pensoft.net/article/148522/" target="_blank" rel="noreferrer noopener">Evolutionary Systematics</a>.



Image Credit: Germán Chávez et. al



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Three new frog species found in Peru face an uncertain future

High in northern Peru, three frogs no bigger than a...

Long before modern climate records began, a very different Earth existed - one where the icy edges of the Arctic were free of permafrost. This wasn't a minor shift. It was a Northern Hemisphere without frozen ground, stretching all the way to the Arctic Ocean. That past could be a preview of our future.



A new study shows that when Earth’s average temperature was just 4.5˚C warmer than it is today, the Asian continent had no permafrost - not even in its far north. This extent of climate warming is within the range we could reach again in the near future if emissions remain unchecked. 



Researchers from <a href="https://www.northumbria.ac.uk/">Northumbria University</a>, the University of Oxford, Bern University, and the Geological Surveys of Israel and the U.S. worked together to trace the ancient climate shift. They found their evidence in an unlikely place: inside caves beneath the Siberian tundra.



<h2 class="wp-block-heading" id="h-frozen-clues-hidden-underground">Frozen clues hidden underground</h2>



The team focused on cave formations known as <a href="https://www.earth.com/news/past-tipping-points-where-the-climate-changed-abruptly/">speleothems</a> - stalagmites and stalactites - which only grow when water can seep through the ground. In regions locked in permafrost, the soil stays frozen solid. That makes speleothem growth impossible. 



So, if these formations exist in caves beneath modern-day permafrost, it means the ground had to be thawed when they formed.



The researchers collected more than 60 mineral samples from caves in the Lena River delta, one of the coldest and most remote areas of northeastern Siberia. 



Using uranium-lead dating, a precise method for measuring tiny traces of radioactive decay, the team determined that the cave minerals had formed about 8.7 million years ago, during the late <a href="https://www.earth.com/news/fossil-site-in-australia-indicates-abundant-life-during-the-miocene/">Miocene</a> period.



This means the ground in that region was thawed at the time. Existing global temperature records show that Earth was 4.5˚C warmer than it is today.



<h2 class="wp-block-heading" id="h-the-fate-of-arctic-permafrost">The fate of Arctic permafrost</h2>



If Earth warms by that same amount again, the findings suggest that all but the deepest or highest-altitude permafrost would melt.



“Our findings provide direct quantitative evidence that if our <a href="https://www.earth.com/news/looking-to-earths-ancient-climate-to-predict-our-future/">climate</a> warms by 4.5˚C, the permafrost currently covering Canada, Siberia, Mongolia, America - in fact much of the Northern Hemisphere - would thaw. Only permafrost in high mountains and deep underground would survive," said Dr Sebastian Breitenbach of Northumbria University.



“This thaw would release billions of tonnes of <a href="https://www.earth.com/news/carbon-sinks-are-losing-their-ability-to-absorb-co2/">carbon</a> from the ground into the atmosphere, enhancing further warming. This finding is a real warning to us all. It shows how sensitive our climate system is and where we might be headed if we don't act to limit our climate emissions now.”



What makes this especially concerning is the sheer volume of carbon at risk. Scientists estimate that up to 130 billion tonnes are locked in today's permafrost. If that carbon is released as the ground thaws, it won't just add to the warming - it will accelerate it.



<h2 class="wp-block-heading" id="h-when-the-arctic-was-permafrost-free">When the Arctic was permafrost-free </h2>



“After much searching, we were fortunate to find well-preserved datable cave deposits in the heart of today’s <a href="https://www.earth.com/news/frozen-worm-comes-back-to-life-after-46000-years/">Siberian permafrost</a>,” said Dr Anton Vaks of the Geological Survey of Israel. 



“We can see that this present-day tundra region experienced a warmer climate, with mean annual global temperatures above 0°C and with permafrost-free conditions." 



According to Dr. Vaks, the evidence from the cave formations indicates that most of the Siberian landmass and likely similar regions in the Northern Hemisphere were permafrost-free when the deposits formed at Taba-Ba’astakh.



<h2 class="wp-block-heading" id="h-caves-as-climate-time-machines">Caves as climate time machines</h2>



Professor Gideon Henderson of the University of Oxford noted that caves are like time machines. 



“They capture a history of the climate and environment for millions of years of Earth history, which we can now read accurately using precise chemical analyses," said Henderson. 



"By doing so, we can predict the future, using past conditions as an analogue for the future to understand the impact of the warmer world we are heading into.



“This new study provides valuable new constraints on the magnitude of warming required to completely destroy permafrost in the northern hemisphere and remove one of the biggest continental stores of carbon.”



The full study was published in the journal <a href="https://www.nature.com/articles/s41467-025-60381-5">Nature Communications</a>.



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Arctic permafrost vanished in the past - will it happen again?

Long before modern climate records began, a very different Earth...

Sexual behavior and preference - whether in humans or animals - isn’t random. It’s shaped early on, during fetal development, by how the brain responds to hormones like androgens (male sex hormones). 



This early exposure is known to affect many important adult traits. But there's been one big obstacle: how do you measure that influence without invasive methods?



<h2 class="wp-block-heading" id="h-rat-fingers-hint-at-sexual-behavior">Rat fingers hint at sexual behavior </h2>



Researchers from <a href="https://www.okayama-u.ac.jp/index_e.html" target="_blank" rel="noreferrer noopener">Okayama University</a> in Japan may have found an answer - by looking at rats’ fingers.



In a recent study, a team led by Professor <a href="https://loop.frontiersin.org/people/32931/overview" target="_blank" rel="noreferrer noopener">Hirotaka Sakamoto</a> and Dr. Himeka Hayashi found that a simple finger measurement - the ratio of the second digit to the fourth digit, known as 2D:4D - can predict sexual behavior and preference in rats.



This digit ratio has been studied in humans for years. On average, men tend to have a lower 2D:4D ratio than women, meaning their index fingers are shorter relative to their ring fingers. 



But surprisingly, there hasn’t been much research testing whether this holds true in other animals, nor has sexual proclivity been measured against 2D:4D ratio in humans or other animals. That’s what drew the researchers to rats.



<h2 class="wp-block-heading" id="h-understanding-the-2d-4d-ratio">Understanding the 2D:4D ratio</h2>



As stated, the 2D:4D ratio compares the lengths of your index finger (2D) and your ring finger (4D). 



To find it, just look at your right hand: if your ring finger is longer than your index finger, your 2D:4D ratio is considered low; if your index finger is about the same length or longer, your ratio is higher. 



Scientists have found that this ratio is set before you're born, influenced by the amount of <a href="https://www.earth.com/news/men-with-low-testosterone-have-a-higher-risk-of-mortality/">testosterone</a> and <a href="https://www.earth.com/news/study-suggests-menopause-can-be-delayed-or-even-eliminated/">estrogen</a> you were exposed to in the womb. 



In general, people with lower ratios were exposed to more testosterone, while higher ratios suggest more estrogen exposure.



This tiny finger difference has caught scientists’ attention because it seems to connect to traits like athletic ability, aggression, risk-taking, and even career interests. 



For example, some studies have found that people with lower 2D:4D ratios tend to do better in competitive sports or lean toward science and engineering fields. 



It’s also been tied to traits like <a href="https://www.earth.com/news/practicing-yoga-nidra-improves-sleep-memory-and-cognition/">cognition</a>, <a href="https://www.earth.com/news/personality-traits-are-not-strongly-inherited-from-parents/">personality</a>, <a href="https://www.earth.com/news/lack-of-sexual-satisfaction-linked-to-rapid-memory-decline/">sex drive</a>, and even <a href="https://www.earth.com/news/same-sex-sexual-behavior-linked-to-evolutionary-advantages-in-monkeys/">sexual orientation</a>.



But it’s not a rule - it’s just a pattern seen in large groups, not a way to predict someone’s future.



<h2 class="wp-block-heading" id="h-shorter-fingers-stronger-sex-drive">Shorter fingers, stronger sex drive</h2>



“We found that the 2D:4D ratio serves as a reliable biological marker for predicting sexual activity in rats,” said Sakamoto. 



“Rats with shorter second digits were not only more sexually active but also showed a clear preference for female scent.”



Building on their initial measurements, the team then ran mating trials to observe <a href="https://www.earth.com/news/science-behind-predicting-and-changing-human-behavior/">behavior</a>.



The results were clear. Male rats that ejaculated during their first encounter had shorter second digits compared to those that didn’t. 



These males also showed signs of higher sexual drive: they ejaculated more often, did so more quickly, and had stronger erectile function.



<h2 class="wp-block-heading" id="h-the-scent-of-sexual-behavior">The scent of sexual behavior </h2>



To go beyond behavior and look at preference, the researchers ran a simple but telling test. They placed male rats in a cage with two kinds of bedding: one scented by females, and the other by males.



All the male rats initially explored the male-scented bedding. But only those with shorter second digits stayed interested in the female-scented bedding. They sniffed, explored, and spent more time with it - indicating a clear sexual preference.



“While most studies have only linked the digit ratio to morphological sex differences, we noticed a surprising lack of research connecting digit ratio to the biological basis of sex itself - especially sexual activity and preference,” notes Hayashi. “This curiosity marked the start of our study.”



<h2 class="wp-block-heading" id="h-fingers-mirror-brain-wiring">Fingers mirror brain wiring</h2>



Beyond offering insight into rat behavior, the study points to a deeper question: how early hormone exposure shapes the brain in lasting ways.



Before birth, hormone exposure might wire our brains in ways that the 2D:4D ratio later reflects - potentially shaping complex behaviors like sexual orientation or emotional attachment.



“Our results suggest a profound link between the body and mind, with significant scientific and clinical implications,” said Sakamoto. “Simply examining our fingers could one day help identify aspects of our behavioral tendencies.”



The findings also offer a practical model for exploring biological questions that are difficult - or impossible - to study directly in humans. 



Because 2D:4D is also connected to cognitive traits and mental health conditions, this research could help explain sex-based differences in disorders like <a href="https://www.earth.com/news/toddler-screen-time-linked-to-atypical-sensory-behaviors/">autism</a>, <a href="https://www.earth.com/news/how-gut-bacteria-morganella-morganii-could-cause-depression-not-a-brain-disorder/">depression</a>, or attachment issues.



<h2 class="wp-block-heading" id="h-biology-is-not-the-whole-story">Biology is not the whole story</h2>



While the findings are compelling, they also raise important questions. For one, it’s still unclear how well results from rats translate to humans. 



Rats provide a useful model for controlled experiments, but human sexuality is influenced by many layers - cultural, social, psychological - that go far beyond biology.



The researchers also focused only on male rats. Future studies will need to explore whether similar patterns hold true for females, and how other factors like environment or stress interact with digit ratios to shape behavior.



Another key question is causation. Rats with shorter 2D:4D finger ratios tend to show more sexual activity and stronger preferences, but scientists aren’t yet sure whether the digit ratio drives this behavior - or if both stem from shared prenatal influences.



None of this takes away from the value of the study. But it highlights the importance of treating biological markers like 2D:4D as part of a much larger picture. 



The full study was published in the journal <a href="https://www.jstage.jst.go.jp/article/expanim/advpub/0/advpub_24-0159/_article" target="_blank" rel="noreferrer noopener">Experimental Animals</a>.



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Does your finger length predict sexual behavior? A new study says yes

Sexual behavior and preference - whether in humans or animals...

For decades, space engineers have imagined shipping steel, glass, and concrete to other worlds so that future explorers can build homes on Mars and even further from Earth.



A new study led by Robin Wordsworth at <a href="https://seas.harvard.edu/">Harvard’s School of Engineering and Applied Sciences</a> turns that idea on its head. Rather than launching heavy construction kits, the team shows that habitats can, quite literally, grow themselves.



“If you have a habitat that is composed of <a href="https://www.earth.com/news/nature-inspired-solutions-new-bioplastic-dissolves-rapidly-in-water/">bioplastic</a>, and it grows algae within it, that algae could produce more bioplastic,” Wordsworth said. “So you start to have a closed-loop system that can sustain itself and even grow through time.”



<h2 class="wp-block-heading" id="h-turning-algae-into-architecture"><a></a>Turning algae into architecture</h2>



At the heart of the concept is Dunaliella tertiolecta, a type of hardy <a href="https://www.earth.com/news/green-algae-in-lake-erie-may-be-hiding-toxic-deadly-compounds/">green algae</a> already used on Earth for aquaculture and biofuel research.



The researchers conducted a series of lab tests where they 3-D printed dome-shaped chambers using polylactic acid (PLA), a common bioplastic fermented from plant sugars.



The walls were only a millimeter thick, but strong enough to hold liquid water even when the outside pressure fell to Mars-like levels of about 600 pascals - more than a hundred times lower than on Earth.



Inside these tiny “greenhouses,” the algae were bathed in carbon-dioxide-rich air, fed with artificial sunlight, and left to do what algae do best: photosynthesize, grow, and multiply.



After ten days, cell counts in low-pressure chambers nearly matched those in cultures grown at normal Earth pressure. This confirmed that life could flourish despite the thin atmosphere.



Light management was another hurdle. Mars receives plenty of visible sunlight, but its surface is bombarded by harmful ultraviolet rays. 



Tests showed that a single millimeter of PLA blocks all UV-C radiation and much of UV-A and UV-B while still letting through the red and blue wavelengths that <a href="https://www.earth.com/news/revealing-the-secrets-of-photosynthesis-through-pep/">photosynthesis</a> requires. In short, the plastic skin both protects and nourishes its green tenants.



<h2 class="wp-block-heading" id="h-self-growing-habitats-on-mars">Self-growing habitats on Mars</h2>



If the algae thrive, the cycle becomes self-amplifying. Researchers can convert extra biomass into fresh PLA, then print or mold it into new habitat walls.



A simple mass-balance analysis in the study suggests that with realistic conversion efficiencies, a foot-deep algae cultivation pond beneath each habitat could produce more than enough bioplastic to meet repair needs. 



This includes material to address routine weathering. Surplus production could even allow the living area to double every couple of years.



In theory, a single lander packed with starter cultures, nutrients, and a modest 3-D printer might seed an entire settlement that grows like coral over time. Operating at low pressure, the domes place far less stress on their walls than habitats built for full Earth pressure.



The team calculated that a one-millimeter PLA shell can comfortably withstand the loads. Reinforcement could come from additional biological materials, such as bacterial cellulose aerogels, which also provide insulation and help maintain plant-friendly temperatures between 10-30 °C (50-86 °F).



<h2 class="wp-block-heading" id="h-algae-domes-for-deep-space">Algae domes for deep space</h2>



Although the experiments targeted Mars, similar biomaterial bubbles could help researchers design life-support systems for the Moon, free-floating space stations, or even harsh environments on Earth.



Wordsworth notes that a later phase of the project will test whether the same strategy can function in a complete vacuum. This is essential for lunar use and will test whether the algae-PLA loop can run without outside resources after kickoff.



“The concept of biomaterial habitats is fundamentally interesting and can support humans living in space,” he said. The progress in off-world <a href="https://www.earth.com/news/scientists-urgent-plea-sustainable-climate-solutions-save-earth-humanity/">sustainability</a> almost invariably “has spinoff benefits for sustainability technology here on Earth as well.”



One immediate benefit is the potential use of the domes as low-energy bioreactors. Unlike conventional indoor farms that rely on electric lamps, algae inside translucent shells harvest natural sunlight. That eliminates a major power drain - a critical advantage on distant worlds where every watt matters.



<h2 class="wp-block-heading" id="h-surviving-mars-extremes">Surviving Mars’ extremes</h2>



Of course, challenges remain. Mars swings through dramatic temperature cycles, and liquid water will freeze solid without extra heating or insulation. 



Perchlorate salts in Martian dust are toxic to many organisms, so engineers will need robust filtration or genetically tuned microbes.



Gas exchange will also need to be balanced. PLA walls allow carbon dioxide to seep in and oxygen to seep out, but water vapor escapes the same way, risking desiccation unless clever humidity controls are included.



Shielding human occupants from <a href="https://www.earth.com/news/deep-space-cosmic-rays-from-supernova-sparked-rapid-earth-evolution/">cosmic radiation</a> also demands thicker or layered shells, perhaps combining PLA with locally mined regolith.



Finally, the team is keen to move from flask-scale proofs to pilot-scale structures that people can walk into. The future domes could pair the algae chambers with silica-aerogel skylights. This technology, developed by Wordsworth’s group, captures sunlight while trapping heat to create temperate oases on an otherwise frigid plain.



<h2 class="wp-block-heading" id="h-bioplastic-homes-grown-by-algae">Bioplastic homes grown by algae</h2>



The broader message of the study is that biology can be both passenger and partner in humanity’s push beyond Earth.



If algae build walls and microbes recycle plastic, habitats could grow and repair themselves instead of being shipped from Earth. Instead, they become living, self-healing ecosystems.



That vision aligns with <a href="https://www.nasa.gov/">NASA</a>’s growing interest in in-situ resource utilization and with wider efforts to craft sustainable, circular economies at home.



In other words, the green slime that clings to your fish tank might one day help roof the first Martian village - and teach us a few lessons about building lighter, cleaner, and smarter back on the pale blue dot.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/sciadv.adp4985">Science Advances</a>.



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Bioplastic bubbles made with algae could sustain life on Mars

For decades, space engineers have imagined shipping steel, glass, and...

Scientists are transforming chocolate into a functional food by infusing it with probiotics and prebiotics, aiming to create a treat that satisfies cravings while supporting gut health. 



The challenge lies in maintaining chocolate's beloved texture and flavor while adding health benefits.



<figure class="wp-block-embed aligncenter is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://youtu.be/Ug657J67iEo?si=w96YjGMsg939LD_3
</div></figure>



Probiotics - beneficial microbes that balance gut bacteria and aid digestion - are typically fragile and can be destroyed by stomach acid or processing. 



Prebiotics act as food for these microbes, helping them thrive. Together, they form "synbiotics," a powerful health combination.



Researchers Smriti Gaur and Shubhi Singh from India's Jaypee Institute of Information Technology took an innovative approach, using natural prebiotics like corn and honey instead of complex processing methods. 



They created five chocolate varieties: a control and four synbiotic versions containing different combinations of prebiotics, probiotics (Lactobacillus strains), and flavor enhancers (cinnamon or orange).



Laboratory simulations of human digestion showed the probiotics remained viable for over five hours, suggesting they could survive long enough to benefit gut health.



Taste tests were positive, with researchers particularly enjoying the orange-flavored variety, describing it as having "vibrant citrus notes" complementing the "rich cocoa" with a "luxurious" texture.



This research represents just the beginning. With further refinement of strains, textures, and flavors, chocolate could evolve beyond mere indulgence to become a functional food that nourishes while it delights.



The study is published in the journal <a href="https://pubs.acs.org/doi/10.1021/acsfoodscitech.4c00741" target="_blank" rel="noreferrer noopener">ACS Food Science &amp; Technology</a>.

Is chocolate the next nutritional powerhouse?

Scientists are transforming chocolate into a functional food by infusing...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Nushagak Bay, a large estuary in southwest Alaska. Nushagak runs mainly north to south and exits in Bristol Bay, a large body of water in the Bering Sea.



"The bay is primarily fed by the Nushagak River, which begins in the Alaska Range and flows southwest approximately 450 km. The bay is also fed by several additional rivers including the Wood, Igushik, Snake and Weary rivers," says ESA.



"The dark colors of the Nushagak River are most likely due to tannins or lignins (chemical substances found in plants). Tannins and lignins from roots, leaves, seeds, bark and soil can leach into the water and give it a brown or even black colour. The sediments then flow southwards where it is mixed with the bluer waters of the bay."



Video/ Image Credit: ESA



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Nushagak Bay in southwest Alaska

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> (ACS) reveals that proteins on flu viruses are actually flexible, tilting and waving in a “breath-like” motion. According to the experts, these proteins could be used to better defend against the flu.



"The main antigenic targets of influenza virus are two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). Whereas the structural and dynamical properties of both glycoproteins have been studied previously, the understanding of their plasticity in the whole-virion context is fragmented," wrote the researchers.



To investigate, the team conducted detailed simulations of the influenza A H1N1 virion, or the swine flu. The experts concluded that the visualizations show many new vulnerable states of flu viruses, which could improve future vaccines and antiviral drugs.



Video/ Image Credit: American Chemical Society&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Flu viruses are more flexible than expected

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Lake Trasimeno, which is located west of Perugia in central Italy. It is the fourth largest lake in the country. While Trasimeno’s water level varies, it has a maximum depth of approximately six meters.&nbsp;



"In this Copernicus Sentinel-2 image, captured on 6 August 2022, the lake’s emerald green colour is likely due to the presence of phytoplankton. Streaks in the water, particularly visible in the west, indicate the presence of soil and sediments which have been stirred up by winds. Dark colored waters in the southern part of the lake indicate a presence of submerged and floating macrophytes (aquatic plants) as well as algae," says ESA.



"Surrounded by hills on three sides, Trasimeno is subject to heavy storms created by winds, especially from the north and west. There are three islets in the lake: Maggiore, Minore and Polvese (the largest). The lake’s shores are sparsely inhabited with only two popular villages: Castiglione del Lago and Passignano sul Trasimeno."



"Italy is experiencing its worst drought in 70 years which has affected drinking water supplies, hydroelectric power and agricultural production. High temperatures, hot winds and lack of rainfall are the main causes of drought in the Umbrian region which saw Lake Trasimeno’s drop 1.3 m, reaching the limit of the hydrometric zero in July 2022."



Video/Image Credit: ESA&nbsp;



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By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Lake Trasimeno in Central Italy

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> describes a new self-powered nanosensor that can instantly detect mercury contamination with the tap of a finger.&nbsp;



The oxidized form of mercury can be harmful when it is ingested through contaminated water or food. This makes it necessary for experts to develop sensors that can quickly and accurately detect the presence of mercury.&nbsp;



Zong-Hong Lin and colleagues have now created a triboelectric nanosensor (TENS) that can detect mercury by simply by touching a sample. According to the researchers, their TENS could serve as the basis for similar devices to safely and remotely monitor other pollutants.



Video Credit: American Chemical Society&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Detecting mercury contamination with the tap of a finger

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Kainji Lake, a reservoir on the Niger River.



In 1968, Kainji Lake was created by the construction of the Kainji Dam. The Niger River, the third longest in Africa, enters the lake in the north.&nbsp;



According to <a href="https://www.earth.com/news/rivers-in-the-american-west-are-a-lifesaving-resource-for-birds/">ESA</a>, the creation of the lake submerged Foge Island and the town of Bussa and permanently flooded other riverine settlements, leaving around 50,000 people displaced.&nbsp;



Large parts of Foge Island are temporarily exposed during low water tides, and the land is often used by migrating fishermen. Kainji Dam is a dam across the Niger River in Niger State of Central Nigeria. 



Wild mammals occur at relatively low densities due to illegal hunting. Lake Kainji has suffered a dramatic decline as a fishery due to the high numbers of artisanal and subsistence fisherfolk using the lake. It has been suggested that a period of closure, together with controlled fishing rights may help improve fish stocks.



Kainji Lake National Park is the oldest of its kind in Nigeria. The park contains three distinct areas: a part of the Kainji Lake, the Borgu Game Reserve to the west of the lake, and the Zugurma Game Reserve to the southeast. The park is home to around 65 mammal species, 350 bird species, and 30 species of reptiles and amphibians. 



Video/ Image Credit: European Space Agency&nbsp;



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By <a href="mailto:csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Editor



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Kainji Lake in north central Nigeria

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While most bears live in the forest with ample space, food, and social interaction, Luna had none of that. She resided in a cramped cage, surrounded by tourists and unfamiliar noises. It was a terrible place. Photo Credit: Daily Mail

Terrible Conditions

Rather than living in nature, Lily grew up in Albania’s Aulona Amusement Park. While it's assumed she was illegally brought to the park by hunters, things only got worse in captivity. Photo Credit: Shon Ellerton

Terrible Conditions

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