Today's Image of the Day from the European Space Agency features the barred spiral galaxy NGC 1559, located around 35 million light-years away in the little-observed southern constellation Reticulum. The image was captured by the James Webb Space Telescope.&nbsp;



<h2 class="wp-block-heading" id="h-fuel-for-star-formation">Fuel for star formation </h2>



"The data featured in this portrait make use of two of Webb’s instruments: the Mid-InfraRed Instrument (MIRI) and Near-InfraRed Camera (NIRCam)," noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



"Here MIRI captures the glow of interstellar dust grains, which trace out the interstellar medium, the fuel for future star formation. NIRCam shows the light from stars, even young stars hidden behind prodigious amounts of dust. NIRCam also captures emission from ionised nebulae around young stars."



<h2 class="wp-block-heading" id="h-webb-reveals-galaxies-in-new-light">Webb reveals galaxies in new light</h2>



According to ESA, the data was collected by the <a href="https://sites.google.com/view/phangs/home">PHANGS team</a> as part of a program in which Webb will observe 55 <a href="https://www.earth.com/news/james-webb-captures-galaxies-that-are-too-old-to-exist/">galaxies</a> that have also been mapped by the Atacama Large Millimeter/submillimeter Array (ALMA) radio telescope, the Hubble Space Telescope, and more.&nbsp;



"By combining Webb’s unprecedented view of the dust and stars with data from these other facilities, the team aims to obtain a new, highly detailed view of how stars are born, live, and die in galaxies across the Universe."



<h2 class="wp-block-heading" id="h-ngc-1559-a-loner-in-space">NGC 1559: A loner in space</h2>



Although NGC 1559 appears to sit close to one of our nearest neighbors in the sky - the Large Magellanic Cloud (LMC) - this is just a trick of perspective, noted ESA.



While it is part of the Reticulum constellation, NGC 1559 is not part of the Local Group of galaxies but instead resides in a more distant region of space.



"In reality, NGC 1559 is physically nowhere near the LMC in space; in fact it truly is a loner, lacking the company of any nearby galaxies or membership of any galaxy cluster."



<h2 class="wp-block-heading" id="h-star-formation-in-ngc-1559">Star formation in NGC 1559</h2>



NGC 1559 is notable for its active star formation and strong magnetic fields. It has also been the site of several <a href="https://www.earth.com/news/supernova-explosions-could-damage-distant-planets/" target="_blank" rel="noreferrer noopener">supernovae</a>, making it of particular interest to astronomers studying stellar evolution and the lifecycle of stars.



The structure of NGC 1559 includes well-defined spiral arms that are rich in young, hot stars and regions of ionized gas, indicative of ongoing <a href="https://www.earth.com/news/black-hole-is-starving-its-host-galaxy-of-star-forming-fuel/" target="_blank" rel="noreferrer noopener">star formation</a>.



The galaxy’s central bar is believed to play a role in driving gas towards the core, fueling both the star formation and the activity around its nucleus.



<h2 class="wp-block-heading" id="h-an-extragalactic-wonder">An extragalactic wonder</h2>



Despite being relatively small compared to larger galaxies like the Milky Way, NGC 1559 is an important object for understanding how barred spiral galaxies evolve and the processes that trigger supernovae.



The galaxy’s remote location and active nature make it a fascinating subject of study in the field of extragalactic astronomy. The isolation of NGC 1559 allows for a clearer view of its structure without much interference from neighboring galaxies.



<h2 class="wp-block-heading" id="h-barred-spiral-galaxies">Barred spiral galaxies</h2>



Barred spiral galaxies are a type of spiral galaxy characterized by a central bar-shaped structure composed of stars. This bar extends out from the core and connects to the galaxy's spiral arms, which swirl outward in a graceful pattern.



Scientists believe that the bar plays a crucial role in the evolution of the galaxy, funneling gas towards the core and potentially triggering star formation or feeding a central black hole. 



The <a href="https://www.earth.com/news/newly-discovered-stars-milky-way-are-old-as-universe/" target="_blank" rel="noreferrer noopener">Milky Way</a>, our own galaxy, is an example of a barred spiral. These galaxies are quite common in the universe, making up about two-thirds of all observed spiral galaxies.



The bar itself is thought to be a temporary feature, developing as the galaxy matures and possibly disappearing over time as the dynamics of the stars change. 



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



The Reticulum constellation is a small, faint constellation in the southern sky. Its name means "the reticle" in Latin, which refers to the crosshairs in an eyepiece of a telescope. 



The constellation was named in the 18th century by the French astronomer Nicolas Louis de Lacaille to honor the reticle he used in his scientific instruments. It is one of the 88 modern constellations recognized by the International Astronomical Union.



Image Credit: ESA/Webb, NASA &amp; CSA, A. Leroy, J. Lee and the PHANGS Team



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Spiral galaxy NGC 1559 is a loner in outer space

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

Today's Image of the Day from the European Space Agency features NGC 1792, a spiral galaxy located in the constellation Columba, about 43 million light-years away from Earth.&nbsp;



This galaxy, discovered by British astronomer James Dunlop in 1826, is part of the larger NGC 1808 group of galaxies.&nbsp;



<h2 class="wp-block-heading" id="h-intimate-view-of-ngc-1792">Intimate view of NGC 1792</h2>



“An orange glow radiates from the center of NGC 1792, the heart of this stellar forge. Captured by the NASA/ESA Hubble Space Telescope, this intimate view of NGC 1792 gives us some insight into this galactic powerhouse,” noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



“The vast swathes of tell-tale blue seen throughout the galaxy indicate areas that are full of young, hot stars, and it is in the shades of orange, seen nearer the center, that the older, cooler stars reside.”



<h2 class="wp-block-heading" id="h-vigorous-star-formation-nbsp">Vigorous star formation&nbsp;</h2>



NGC 1792 is notable for its vigorous star formation, classifying it as a starburst galaxy. This high rate of star formation is thought to be triggered by gravitational interactions with neighboring galaxies, though the exact cause is still under study.



“Nestled in the constellation of Columba (The Dove), NGC 1792 is both a spiral galaxy, and a starburst galaxy,” said ESA. “Within starburst galaxies, stars are forming at comparatively exorbitant rates. The rate of star formation can be more than 10 times faster in a starburst galaxy than in the Milky Way.”



<h2 class="wp-block-heading" id="h-fierce-bursts-of-star-formation">Fierce bursts of star formation</h2>



ESA noted that when galaxies have a large reservoir of gas, like NGC 1792, these short-lived starburst phases can be sparked by galactic events such as mergers and tidal interactions.&nbsp;



“One might think that these starburst galaxies would easily consume all of their gas in a large forming event. However, supernova explosions and intense stellar winds produced in these powerful starbursts can inject energy into the gas and disperse it.”&nbsp;



“This halts the star formation before it can completely deplete the galaxy of all its fuel. Scientists are actively working to understand this complex interplay between the dynamics that drive and quench these fierce bursts of star formation.”



Due to its distance and brightness, NGC 1792 can be observed with medium-sized telescopes under favorable conditions.



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



Galaxy evolution refers to the process by which galaxies form and change over time. It begins in the early universe, shortly after the <a href="https://www.earth.com/news/new-observations-disprove-big-bang-theory-universe-began-tired-light-theory/" target="_blank" rel="noreferrer noopener">Big Bang</a>, when small density fluctuations in the primordial gas led to the collapse of matter into the first galaxies. 



<h3 class="wp-block-heading" id="h-galaxy-mergers">Galaxy mergers</h3>



These early galaxies were small and irregular, composed mostly of gas and dark matter. Over billions of years, galaxies grew larger by merging with one another and by accreting gas from the surrounding space.&nbsp;



These interactions often triggered bursts of star formation, and collisions between galaxies sometimes led to the creation of new, more massive galaxies.



<h3 class="wp-block-heading" id="h-structural-changes">Structural changes</h3>



As galaxies evolve, their morphology - their shape and structure - can change. Early galaxies were often irregular or disk-shaped, but over time, many galaxies formed into the elliptical or spiral shapes we see today.&nbsp;



<h3 class="wp-block-heading" id="h-star-formation">Star formation</h3>



Star formation is a key driver of galaxy evolution, but it gradually slows down as galaxies age. 



The gas that fuels <a href="https://www.earth.com/news/black-hole-is-starving-its-host-galaxy-of-star-forming-fuel/" target="_blank" rel="noreferrer noopener">star formation</a> can be used up, or it can be heated and pushed out of galaxies by supernovae or black holes, reducing the galaxy's ability to form new stars.



<h3 class="wp-block-heading" id="h-galaxy-environment-nbsp">Galaxy environment&nbsp;</h3>



The environment in which a galaxy resides also plays a role in its evolution. Galaxies in dense clusters are more likely to interact with their neighbors, which can alter their shape or trigger bursts of star formation.&nbsp;



In contrast, galaxies in more isolated regions of space evolve more slowly and without as many dramatic interactions.



<h3 class="wp-block-heading" id="h-dark-matter">Dark matter</h3>



Dark matter also plays a crucial role in galaxy evolution. It provides the gravitational framework that holds galaxies together and influences their interactions with one another.&nbsp;



Supermassive <a href="https://www.earth.com/search-results/?search=Galaxies%20merge&amp;start=0" target="_blank" rel="noreferrer noopener">black holes</a>, found at the centers of most large galaxies, can also affect their evolution by releasing energy that impacts star formation and the movement of gas within the galaxy.



Overall, galaxy evolution is a complex and ongoing process driven by interactions between stars, gas, <a href="https://www.earth.com/news/study-dark-matter-does-not-exist-and-the-universe-is-27-billion-years-old/" target="_blank" rel="noreferrer noopener">dark matter</a>, and black holes, and shaped by both internal processes and external influences.



Image Credit: ESA/Hubble &amp; NASA, J. Lee



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NGC 1792: A galactic powerhouse 

Today's Image of the Day from NASA Earth Observatory features the Fedchenko Glacier in the Pamir Mountains of Tajikistan. It is one of the world's longest glaciers outside of the polar regions.&nbsp;



“An astronaut aboard the International Space Station took this photo of glaciers in the high-elevation valleys of the Pamir Mountains of Central Asia. The upper portion of Fedchenko Glacier crosses the center of the scene.”



NASA noted that most of the larger glaciers in the image show a prominent pattern of light- and dark-brown parallel lines.&nbsp;



“The darker ‘streamlines,’ known as medial moraines, give a sense of the direction of flow of the ice down the valleys. These are concentrations of debris that has been eroded by the glacier from the adjacent mountainsides or a rocky outcrop,” said NASA.



<h2 class="wp-block-heading" id="h-fedchenko-a-high-altitude-glacier">Fedchenko: A high-altitude glacier</h2>



Fedchenko Glacier stretches for approximately 48 miles and covers an area of around 270 square miles. This massive glacier is a critical source of <a href="https://www.earth.com/news/satellites-reveal-a-sudden-drop-in-global-freshwater-levels/" target="_blank" rel="noreferrer noopener">freshwater</a>, feeding several rivers and influencing the region's hydrology.



Fedchenko Glacier lies at high altitudes, with its origins in the high peaks of the Pamirs, where snow accumulates heavily. Despite being situated in a relatively arid region, the glacier's significant size and volume are maintained by substantial snowfall.&nbsp;



Named after Alexei Pavlovich Fedchenko, a Russian explorer and naturalist, the glacier was first surveyed in 1928 during Soviet-era expeditions. It plays a crucial role in climate studies, as changes in its length and mass provide insights into the effects of global warming in Central Asia.&nbsp;



The glacier is also part of a spectacular and remote landscape, surrounded by towering <a href="https://www.earth.com/news/early-humans-preferred-the-mountains-and-it-changed-our-evolution/" target="_blank" rel="noreferrer noopener">mountains</a> and rugged terrain, making it a key feature of the Pamirs' natural beauty.&nbsp;



<h2 class="wp-block-heading" id="h-threats-to-glaciers-worldwide">Threats to glaciers worldwide</h2>



Like many glaciers worldwide, Fedchenko faces the threat of retreat due to <a href="https://www.earth.com/news/peru-has-lost-over-half-of-its-glaciers-in-six-decades/" target="_blank" rel="noreferrer noopener">global warming</a>, raising concerns about water availability and ecosystem changes in the region.



Rising global temperatures caused by greenhouse gas emissions are the primary driver of glacier melting. Warmer temperatures not only melt glacier surfaces but also increase the flow of meltwater beneath them, accelerating their disintegration.



<h3 class="wp-block-heading" id="h-human-activities-and-pollution-nbsp">Human activities and pollution&nbsp;</h3>



Deforestation and urbanization exacerbate these effects by reducing reflective snow cover and increasing heat absorption in nearby areas.&nbsp;



Airborne pollutants like soot and black carbon darken glacier surfaces, reducing their ability to reflect sunlight and speeding up the rate of melting. 



Industrial activities and tourism in glacier regions add physical stress and pollution, further degrading these fragile ecosystems.



<h3 class="wp-block-heading" id="h-water-supplies">Water supplies</h3>



The loss of glaciers has far-reaching consequences. It disrupts freshwater supplies for millions of people who depend on glacial runoff for drinking water, agriculture, and hydropower.&nbsp;



<h3 class="wp-block-heading" id="h-rising-sea-levels">Rising sea levels</h3>



<a href="https://www.earth.com/news/melting-glaciers-unleash-invasive-species-into-unexpected-areas/" target="_blank" rel="noreferrer noopener">Melting glaciers</a> contribute to rising sea levels, threatening coastal communities and ecosystems worldwide. Additionally, the loss of glaciers impacts biodiversity, as many species rely on cold, glacial habitats for survival.



<h3 class="wp-block-heading" id="h-protecting-glaciers">Protecting glaciers</h3>



Efforts to mitigate these threats focus on reducing <a href="https://www.earth.com/news/melting-glaciers-are-hidden-sources-of-greenhouse-gases/" target="_blank" rel="noreferrer noopener">greenhouse gas</a> emissions, protecting glacier regions from industrial exploitation, and promoting sustainable tourism practices.&nbsp;



However, without urgent action, the continued decline of glaciers will have profound implications for the planet's climate, water systems, and ecosystems.



<h2 class="wp-block-heading" id="h-the-pamir-mountains-nbsp">The Pamir Mountains&nbsp;</h2>



The Pamir Mountains, often called the "Roof of the World," are a vast and rugged mountain range located in Central Asia.&nbsp;



They span across Tajikistan, Afghanistan, China, and Kyrgyzstan, forming a vital part of the junction where the Himalayas, the Tian Shan, the Karakoram, the Kunlun, and the Hindu Kush converge.&nbsp;



With peaks soaring over 7,000 meters, including Ismoil Somoni Peak, the range is home to some of the highest altitudes on Earth.



The Pamir Mountains have been central to trade and cultural exchange for centuries, serving as a critical segment of the ancient Silk Road.&nbsp;



Today, the mountains are a popular destination for trekkers and explorers drawn by their breathtaking beauty and challenging terrain.



The Pamirs are not only a natural wonder but also a biological treasure trove, supporting unique wildlife that is adapted to extreme altitudes.&nbsp;



Culturally, the mountains are home to diverse communities, each with its unique traditions and ways of life, shaped by the harsh but majestic environment.



Image Credit: NASA Earth Observatory



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Fedchenko Glacier in the Pamir Mountains

Today's Image of the Day from NASA Earth Observatory features...

Today's Image of the Day from the European Space Agency features the spiral galaxy IC 5332, which is located over 29 million light-years away from Earth.



The galaxy spans approximately 66,000 light-years in diameter. This makes it notably smaller than our <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</a>, which is just over 100,000 light-years in diameter. 



<h2 class="wp-block-heading" id="h-unprecedented-look-at-ic-5332">Unprecedented look at IC 5332</h2>



In a stunning photo release by NASA and ESA in 2022, the spiral galaxy IC 5332 was presented in an unprecedented level of detail. The images were captured by the <a href="https://www.earth.com/news/james-webb-captures-incredible-new-image-of-uranus/" target="_blank" rel="noreferrer noopener">James Webb Space Telescope</a>.



This feat was made possible through the use of the Mid-InfraRed Instrument (MIRI), which captures images in the mid-infrared spectrum.



<h2 class="wp-block-heading" id="h-unique-perspective-from-earth">Unique perspective from Earth</h2>



One of the most striking features of IC 5332, as revealed by these observations, is its almost perfect face-on orientation relative to Earth.&nbsp;



This unique perspective allows astronomers to clearly observe and admire the symmetrical arrangement of its spiral arms.



<h2 class="wp-block-heading" id="h-webb-unveils-ic-5332-in-new-light">Webb unveils IC 5332 in new light</h2>



The clarity of these images represents a significant advancement over previous observations made by the Hubble Space Telescope, which imaged IC 5332 in ultraviolet and visible light.&nbsp;



While Hubble’s images revealed the galaxy’s symmetrical spiral arms, James Webb’s MIRI has unveiled these structures as a complex web of gas that emits infrared light at various temperatures.



<h2 class="wp-block-heading" id="h-the-miri-instrument-on-james-webb-nbsp">The MIRI instrument on James Webb&nbsp;</h2>



Capturing this range of infrared light is no simple task. It requires highly specialized instruments that must be maintained at extremely cold temperatures.&nbsp;



The MIRI instrument on the James Webb Space Telescope is specifically designed for this purpose and performs exceptionally well. Its capabilities allow astronomers to see aspects of <a href="https://www.earth.com/news/james-webb-captures-galaxies-that-are-too-old-to-exist/" target="_blank" rel="noreferrer noopener">galaxies</a> that are otherwise hidden in other wavelengths.



The detailed images provided by MIRI offer more than just a visual spectacle; they provide valuable data about the composition and temperature of the gases that make up the spiral arms of IC 5332. 



This can help scientists understand the processes of star formation within the galaxy and how these processes compare to those in our own <a href="https://www.earth.com/news/stars-at-the-edge-of-our-milky-way-galaxy-travel-more-slowly/" target="_blank" rel="noreferrer noopener">Milky Way</a>.



<h2 class="wp-block-heading" id="h-webb-finds-hidden-features-of-the-universe-nbsp">Webb finds hidden features of the universe&nbsp;</h2>



The images of IC 5332 served as a critical test of the James Webb Space Telescope’s capabilities in observing the universe in infrared light. 



As astronomers continue to explore with Webb’s full suite of instruments, many more hidden features of the universe will be revealed.



The information provided by the <a href="https://www.earth.com/news/webb-telescope-discovers-second-most-distant-galaxy-in-pandoras-cluster/" target="_blank" rel="noreferrer noopener">James Webb Space Telescope</a> not only expands our understanding of the cosmos but also enhances our appreciation for the complex and beautiful structures that exist in our universe.&nbsp;



<h2 class="wp-block-heading" id="h-spiral-galaxies-like-ic-5332">Spiral galaxies like IC 5332</h2>



Spiral galaxies are some of the most visually striking objects in the universe, characterized by their rotating arms that extend from a central nucleus, giving them a distinct spiral appearance.&nbsp;



These galaxies are primarily made up of a flat, rotating disk containing stars, gas, and dust, and a central concentration of stars known as the bulge. These are often surrounded by a much fainter halo of stars, many of which reside in globular clusters.



Spiral galaxies differ from other galaxy types, such as elliptical and irregular galaxies, in their structure and content. 



The spiral arms are sites of ongoing star formation and are brighter than the rest of the disk because of the young, hot stars that are typically found there. The arms appear distinct because of their density waves, which compress the gas and dust, leading to star formation.



The rotation of the spiral arms also contributes to the galaxy's flat shape due to the centrifugal forces acting on the disk. The central bulge can vary in size and often contains older, red stars.&nbsp;



<h2 class="wp-block-heading" id="h-barred-spiral-galaxies-nbsp">Barred spiral galaxies&nbsp;</h2>



Some spiral galaxies have a bar-shaped structure that extends from the central bulge, making them barred spirals. This bar affects the motion of stars and gas within the galaxy and can influence star formation activity.



Spiral galaxies are an important focus of study because they contain a significant amount of visible matter and play a crucial role in understanding the formation and evolution of galaxies.&nbsp;



Their distinct features also make them particularly useful for studying the laws of physics under extreme conditions, such as high densities and velocities.



Image Credit: <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>/Webb, NASA &amp; CSA, J. Lee and the PHANGS-JWST and PHANGS-HST Teams



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Spiral galaxy IC 5332: A complex web of gas and light

Today's Image of the Day from the European Space Agency features the star-forming region NGC 604, which is located 2.73 million light-years away from Earth in the Triangulum Galaxy (M33). The image was captured by the James Webb Space Telescope.



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 in understanding 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 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. 



<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 NASA Earth Observatory features the Ruki River in the Democratic Republic of the Congo (DRC). It is a tributary of the Congo River, one of the largest rivers in the world by discharge and depth.&nbsp;



The Ruki River, previously known as the Busira, merges with the Momboyo River near the town of Basankusu to become the Lulonga River, which eventually flows into the Congo River at the town of Lisala.



<h2 class="wp-block-heading" id="h-dark-waters-of-the-ruki-river">Dark waters of the Ruki River</h2>



"If the appearance of the muddy Amazon River evokes a coffee cut with cream, the Ruki River, coursing gently through the Congo Basin, is like a dark tea," said <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA</a>.



"On its slow path through mostly untouched lowland rainforest in the Democratic Republic of Congo (DRC), the water leaches organic material from vegetation, prompting some researchers to think it is one of the darkest blackwater rivers on Earth."



According to NASA, scientists are finding that the dissolved material in this distinctive water offers clues about the carbon cycle of tropical forests.



<h2 class="wp-block-heading" id="h-organic-compounds-in-the-ruki-river">Organic compounds in the Ruki River</h2>



In a recent study, researchers measured the chemical <a href="https://www.earth.com/news/warmer-rivers-keep-antimicrobial-resistant-genes-at-bay/" target="_blank" rel="noreferrer noopener">composition</a> and flow of the Ruki for the first time.&nbsp;



"The study reported that, as the water color suggests, the Ruki is rich in dissolved organic carbon compounds," said NASA.



"It contains four times as much organic carbon as the Congo River and 1.5 times as much as the Rio Negro, the world’s largest blackwater river and a major tributary of the Amazon."



Due to this heavy carbon load, the researchers concluded that tropical forests like those around the Ruki might not accumulate quite as much carbon as we once thought.



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



The river is vital for the livelihoods of local communities. <a href="https://www.earth.com/news/fishing-communities-cooperate-to-survive-climate-change/" target="_blank" rel="noreferrer noopener">Fishing</a> is a crucial activity, with many people depending on it for sustenance and income. The river also supports agriculture along its banks, where communities grow crops.



In many parts of the DRC, <a href="https://www.earth.com/news/rivers-are-warming-up-and-losing-oxygen-faster-than-oceans/" target="_blank" rel="noreferrer noopener">rivers</a> like the Ruki are crucial transportation corridors due to the challenging and often nonexistent road infrastructure. 



The river enables the movement of people and goods, facilitating trade and access to markets, health care, and education.



<h2 class="wp-block-heading" id="h-wildlife-of-the-ruki-river">Wildlife of the Ruki River </h2>



The region around the Ruki River is home to diverse wildlife. It is part of the Congo Basin, the second-largest tropical rainforest area in the world, which is a critical habitat for endangered species.



Among the most notable species are elephants and <a href="https://www.earth.com/news/study-mean-chimpanzees-fare-better-in-life-than-nice-ones/" target="_blank" rel="noreferrer noopener">chimpanzees</a>, whose populations thrive in the surrounding forests. Other primates such as bonobos also live in this region, making it a critical area for primate conservation.



The river itself is home to various species of fish that are crucial to local livelihoods. Hippopotamuses and crocodiles are often found in the water.



Birds like kingfishers, herons, and egrets frequent the riverbanks - making it a haven for birdwatchers.



The Ruki River also supports several species of reptiles and amphibians - some of which are unique to the region.



<h2 class="wp-block-heading" id="h-managing-the-river-s-resources">Managing the river's resources </h2>



The region faces several challenges, including <a href="https://www.earth.com/news/global-deforestation-directly-linked-to-atmospheric-mercury-emissions/" target="_blank" rel="noreferrer noopener">deforestation</a>, overfishing, and environmental degradation, which threaten its ecological balance and the livelihoods of people who depend on it. 



Efforts to manage and conserve the river's resources are vital for sustainable development.



Understanding and protecting the Ruki River and its surroundings are crucial for the DRC's environmental sustainability, economic development, and the well-being of its communities.



<h2 class="wp-block-heading" id="h-landscapes-of-the-drc">Landscapes of the DRC</h2>



The Democratic Republic of Congo (DRC) boasts some of the most diverse and breathtaking landscapes in Africa, reflecting its vast size and ecological richness. Dominated by the Congo Basin, the country is a haven for biodiversity.



Beyond its rainforests, the DRC's landscapes shift dramatically. In the east, the terrain rises into rugged mountains, including the Virunga and Rwenzori ranges, where snow-capped peaks like Mount Stanley pierce the sky. 



This region is also marked by active volcanoes such as Mount Nyiragongo, which harbors one of the world’s largest lava lakes, creating a dramatic and otherworldly spectacle.



To the south and west, the country transitions to expansive savannas with rolling grasslands and scattered trees. These areas contrast sharply with the lushness of the forests, providing vital habitats for species like lions and antelope. 



Rivers like the Ruki are a dominant feature, with the mighty Congo River coursing through the heart of the country. Its tributaries shape the lives of millions.



The image was captured by the OLI (Operational Land Imager) on Landsat 8.



Image Credit: NASA Earth Observatory&nbsp;



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Ruki River in the Democratic Republic of the Congo

The Bobcat fire rages on in southern California. Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> captures the impact of the Bobcat fire across the San Gabriel Mountains of Southern California. 

The dark red portion of this false-color photo represents burn scars, while the brighter red areas signify active fires. The Bobcat fire rages on in southern California

By September 23, the <a href="http://www.earth.com/image/the-bobcat-fire-rages-on-in-southern-california/">Bobcat f</a>ire had burned for 18 days, consumed over 113,000 acres, and more than 1,500 firefighters had managed to reach 38 percent containment.

Some media reports suggest that it could take weeks to fully contain the Bobcat fire. Meanwhile, dozens of other devastating wildfires are still raging in the western United States and hundreds of thousands of people are displaced.

The image was captured on September 21, 2020 by the Operational Land Imager (OLI) on the Landsat 8 satellite. California is a state in the <a class="mw-redirect" title="Pacific states" href="https://en.wikipedia.org/wiki/Pacific_states">Pacific Region</a> of the <a class="mw-redirect" title="United States of America" href="https://en.wikipedia.org/wiki/United_States_of_America">United States of Ame</a>r<a class="mw-redirect" title="United States of America" href="https://en.wikipedia.org/wiki/United_States_of_America">ica</a>. With over 39.3 million residents across a total area of about 163,696 square miles (423,970 km2), California is the most populous U.S. state and the <a title="List of U.S. states and territories by area" href="https://en.wikipedia.org/wiki/List_of_U.S._states_and_territories_by_area">third-largest</a> by area, and is also the world's thirty-fourth most populous subnational entity. California is also the most populated subnational entity in North America, and has its state capital in Sacramento. The Greater Los Angeles area and the <a title="San Francisco Bay Area" href="https://en.wikipedia.org/wiki/San_Francisco_Bay_Area">San Francisco Bay Area</a> are the nation's second- and fifth-most populous <a title="Statistical area (United States)" href="https://en.wikipedia.org/wiki/Statistical_area_(United_States)">urban regions</a>, with 18.7 million and 9.7 million residents respectively.<a href="https://en.wikipedia.org/wiki/California#cite_note-13">[13]</a> <a title="Los Angeles" href="https://en.wikipedia.org/wiki/Los_Angeles">Los Angeles</a> is California's <a title="List of largest California cities by population" href="https://en.wikipedia.org/wiki/List_of_largest_California_cities_by_population">most populous city</a>, and the country's <a title="List of United States cities by population" href="https://en.wikipedia.org/wiki/List_of_United_States_cities_by_population">second-most populous</a>, after <a title="New York City" href="https://en.wikipedia.org/wiki/New_York_City">New York City</a>. California also has the nation's <a title="List of the most populous counties in the United States" href="https://en.wikipedia.org/wiki/List_of_the_most_populous_counties_in_the_United_States">most populous county</a>, <a title="Los Angeles County, California" href="https://en.wikipedia.org/wiki/Los_Angeles_County,_California">Los Angeles County</a>, and its <a title="List of the largest counties in the United States by area" href="https://en.wikipedia.org/wiki/List_of_the_largest_counties_in_the_United_States_by_area">largest county</a> by area, <a title="San Bernardino County, California" href="https://en.wikipedia.org/wiki/San_Bernardino_County,_California">San Bernardino County</a>. 

Image Credit: NASA Earth Observatory 

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

The Bobcat fire rages on in southern California

Color,Laser,Beams,Fantail,In,A,Haze

Can light itself, perhaps from a laser, cast a shadow? It might seem like a trick, but under certain conditions, the answer to this paradoxical question is "yes." 



Researchers have discovered that a laser beam can act like an opaque object, blocking another beam of light and creating a visible shadow. 



This finding challenges our traditional understanding of how light behaves.



"Laser light casting a shadow was previously thought impossible since light usually passes through other light without interacting," said Raphael A. Abrahao, the research team leader from <a href="https://www.bnl.gov/world/" target="_blank" rel="noreferrer noopener">Brookhaven National Laboratory</a> and the <a href="https://www.uottawa.ca/en" target="_blank" rel="noreferrer noopener">University of Ottawa</a>.



His team has opened the door to new ways of thinking about light and its interactions, pushing the boundaries of optics and could lead to innovative technologies that harness light in unexpected ways.



<h2 class="wp-block-heading" id="h-lasers-lights-and-lunch">Lasers, lights, and lunch</h2>



The idea started over a lunch conversation. 



Some scientists noticed that experimental schematics made with 3D visualization software depicted the shadow of a <a href="https://www.earth.com/news/earth-received-laser-communication-from-10-million-miles-away/" target="_blank" rel="noreferrer noopener">laser beam</a>, treating it as a solid cylinder rather than accounting for the physics of light. 



This sparked a lively discussion. 



"What started as a funny discussion over lunch led to a conversation on the physics of lasers and the nonlinear optical response of materials," remembered Abrahao. 



"From there, we decided to conduct an experiment to demonstrate the shadow of a <a href="https://www.earth.com/news/impossible-quantum-effects-observed-atoms-positioned-closely-together/" target="_blank" rel="noreferrer noopener">laser beam</a>."



<h2 class="wp-block-heading" id="h-making-laser-light-cast-a-shadow">Making laser light cast a shadow</h2>



To explore this curious idea, the team set up an experiment using a high-power green laser directed through a cube made of standard ruby crystal. 



At the same time, they illuminated the cube with a blue laser from the side. When the green laser entered the ruby, it changed the material's response to the <a href="https://www.earth.com/news/long-term-effects-of-artificial-blue-light-remain-unknown/" target="_blank" rel="noreferrer noopener">blue wavelength</a>. 



The interaction between the two light sources created a shadow on a screen -- a dark area where the green laser blocked the blue light.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/11/laser-beam-light_casing-shadow_credit-Optica_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/11/laser-beam-light_casing-shadow_credit-Optica_1s.webp" alt="Researchers showed that a laser beam can sometimes act like a solid object and cast a shadow that is visible to the naked eye. In the picture, the shadow appears as the horizontal line traversing the blue background. Credit: R. A. Abrahao, H. P. N. Morin, J. T. R. Pagé, A. Safari, R. W. Boyd, J. S. Lundeen" class="wp-image-1950880"/></a><figcaption class="wp-element-caption">Researchers showed that a laser beam can sometimes act like a solid object and cast a shadow that is visible to the naked eye. In the picture, the shadow appears as the horizontal line traversing the blue background. Credit: R. A. Abrahao, H. P. N. Morin, J. T. R. Pagé, A. Safari, R. W. Boyd, J. S. Lundeen</figcaption></figure>



The effect occurs due to a nonlinear optical process. Nonlinear optics involves light interacting with a material in an intensity-dependent way, allowing one light beam to influence another. 



"Our demonstration of a very counter-intuitive optical effect invites us to reconsider our notion of shadow," Abrahao explained. 



In this case, the green laser increased the optical absorption of the blue laser in the ruby crystal, creating a region where less blue light passed through -- essentially, a shadow.



<h2 class="wp-block-heading" id="h-very-cool-but-why-does-it-matter">Very cool, but why does it matter?</h2>



Nonlinear optics is a field that studies how light behaves in materials under high-intensity conditions. 



When light is intense enough, it can change the properties of the material it passes through, affecting how other light waves move through that material. 



This is different from linear optics, where light beams pass through each other without interaction.



"Our understanding of shadows has developed hand-in-hand with our understanding of light and optics," Abrahao noted. 



This new finding could prove useful in various applications such as <a href="https://www.earth.com/news/bose-einstein-condensate-bec-rare-form-quantum-matter-created-with-molecules/" target="_blank" rel="noreferrer noopener">optical switching</a> -- devices in which light controls the presence of another light -- or technologies that require precise control of light transmission, like high-power lasers. 



It could also impact the development of optical computing, where light is used instead of electricity to process information.



<h2 class="wp-block-heading" id="h-measuring-laser-light-s-shadow">Measuring laser light's shadow</h2>



The researchers measured the shadow's contrast based on the laser beam's power, finding a maximum contrast of approximately 22%. 



That's similar to the contrast of a tree's shadow on a sunny day. They also developed a theoretical model that accurately predicted the shadow contrast. 



This alignment between experiment and theory strengthens the validity of their findings.



The ability to control one light beam with another could lead to advances in <a href="https://www.earth.com/news/new-data-transmission-speed-record-set-by-scientists-using-optical-cables/" target="_blank" rel="noreferrer noopener">optical communication</a> and signal processing. 



For instance, optical switches that use light instead of electronic signals could operate at much higher speeds and with less energy loss. 



This discovery might also contribute to the development of new types of lasers with adjustable properties for use in medicine, manufacturing, or scientific research.



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



"This discovery expands our understanding of light-matter interactions and opens up new possibilities for utilizing light in ways we hadn’t considered before," Abrahao concluded. 



The team plans to investigate other materials and laser wavelengths that can produce similar effects. They are curious to see how different combinations might enhance or alter the shadow effect.



The notion that light can cast a shadow on light challenges fundamental ideas in physics. It invites scientists and engineers to rethink how we can manipulate light for advanced technologies. 



This discovery is a reminder that even well-established concepts can be revisited and that curiosity can lead to surprising insights.



From a casual conversation to a laboratory breakthrough, the journey of this discovery highlights the importance of questioning assumptions. The shadow of a laser beam is just one example of how much more there is to learn.



The full study was published in the journal <a href="https://opg.optica.org/optica/fulltext.cfm?uri=optica-11-11-1549&amp;id=563468" target="_blank" rel="noreferrer noopener">Optica</a>.



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Laser beam stuns scientists by casting a shadow, something it shouldn't be able to do

Can light itself, perhaps from a laser, cast a shadow?...

Dark matter has always been one of the biggest mysteries in astrophysics. While we can't see it directly, most scientists are certain it's out there because of its gravitational pull on galaxies. The "Dark Big Bang" theory may have the answer. 



What if dark matter came from its own separate <a href="https://www.earth.com/news/if-the-big-bang-theory-is-correct-what-exactly-happened/" target="_blank" rel="noreferrer noopener">Big Bang</a>, a kind of cosmic encore that happened after the original Big Bang we all know about?



While we can't see it directly, most scientists are certain it's out there. But where did it come from?



Assistant Professor Cosmin Ilie and student researcher Richard Casey are shedding new light on this cosmic enigma. 



They've been exploring an intriguing idea that might change how we understand the origins of dark matter.



<h2 class="wp-block-heading" id="h-dark-big-bang-theory">Dark Big Bang Theory</h2>



Their work at <a href="https://www.colgate.edu/" target="_blank" rel="noreferrer noopener">Colgate University</a> builds on a concept proposed by scientists Katherine Freese and Martin Winkler from the <a href="https://www.utexas.edu/" target="_blank" rel="noreferrer noopener">University of Texas at Austin</a>. 



In 2023, Freese and Winkler suggested that dark matter might have its own origin story -- a separate event they're calling the "Dark Big Bang." 



This event could have occurred shortly after the conventional Big Bang, adding a new chapter to the universe's early history.



Typically, we think of the <a href="https://www.earth.com/news/new-observations-disprove-big-bang-theory-universe-began-tired-light-theory/" target="_blank" rel="noreferrer noopener">Big Bang</a> as the singular event that created all matter, including dark matter. But this new theory proposes that dark matter was born from a distinct process. 



It involves a quantum field that only interacts with the dark sector and starts out trapped in a false vacuum state. 



When it decays, it could produce dark matter particles in a burst of energy akin to a second Big Bang.



<h2 class="wp-block-heading" id="h-understanding-dark-matter">Understanding dark matter</h2>



When we look at how galaxies rotate or how light bends around massive objects (a phenomenon called <a href="https://www.earth.com/news/rare-carousel-lens-galaxy-alignment-reveals-dark-matter-secrets/" target="_blank" rel="noreferrer noopener">gravitational lensing</a>), we notice things don't add up unless there's some invisible mass exerting extra gravity.



Scientists have been scratching their heads over <a href="https://www.earth.com/news/study-dark-matter-does-not-exist-and-the-universe-is-27-billion-years-old/" target="_blank" rel="noreferrer noopener">what dark matter actually is</a>. It's not made of the same particles that make up stars, planets, and us. 



It doesn't interact with electromagnetic forces, which is why it doesn't glow, reflect, or block light. 



Think of it as an invisible framework that holds galaxies together. Without <a href="https://www.earth.com/news/dark-matter-may-consist-of-particles-that-travel-faster-than-light/" target="_blank" rel="noreferrer noopener">dark matter</a>, galaxies would probably fly apart because there's not enough visible mass to keep them intact. 



So, while we can't see dark matter directly, its gravitational fingerprints are all over the cosmos.



<h2 class="wp-block-heading" id="h-what-exactly-is-the-big-bang">What exactly is the Big Bang?</h2>



This theory suggests that everything we see today -- from the tiniest particles to the largest galaxies -- began from an unimaginably hot and dense state about 13.8 billion years ago. 



At that moment, the universe didn't explode into space; rather, space itself began expanding. All matter, energy, space, and even time came into existence and started stretching outwards.



Think of it like this: the universe was once compressed into a point smaller than an atom, and then it started expanding and cooling. 



This expansion allowed particles to form atoms, which eventually led to the creation of stars and galaxies. 



We see evidence of this event in the <a href="https://www.earth.com/news/deep-space-is-even-darker-than-we-imagined/" target="_blank" rel="noreferrer noopener">cosmic microwave background radiation</a>, which is like a faint afterglow left over from the Big Bang.



<h2 class="wp-block-heading" id="h-dark-matter-and-the-big-bang">Dark matter and the Big Bang</h2>



Ilie and Casey took this concept and ran with it. In their recent study, they examined all the ways this Dark Big Bang could fit within what we already know from experiments and observations. 



Most excitingly, they uncovered a range of scenarios that hadn't been considered before, opening up new possibilities for how dark matter came to be.



“Detecting gravitational waves generated by the Dark Big Bang could provide crucial evidence for this new theory of dark matter,” said Ilie. 



He believes that upcoming experiments could give us the tools we need to test this idea like never before.



<h2 class="wp-block-heading" id="h-gravitational-waves-and-the-dark-big-bang">Gravitational waves and the Dark Big Bang</h2>



Gravitational waves are ripples in the fabric of space-time, caused by massive events like merging black holes or <a href="https://www.earth.com/news/neutron-stars-may-hold-the-key-to-understanding-dark-matter/" target="_blank" rel="noreferrer noopener">neutron stars</a>. 



The 2023 detection of background gravitational waves by the NANOGrav collaboration might be linked to this Dark Big Bang. If that's the case, we could be on the verge of a major breakthrough.



“With current experiments like the International Pulsar Timing Array (IPTA) and the <a href="https://www.skao.int/en" target="_blank" rel="noreferrer noopener">Square Kilometer Array</a> (SKA) on the horizon, we may soon have the tools to test this model in unprecedented ways,” Ilie added. 



These experiments could detect the specific <a href="https://www.earth.com/news/quantum-particles-solution-gravitational-wave-mystery-bose-einstein-condensate/" target="_blank" rel="noreferrer noopener">gravitational wave</a> signals predicted by the Dark Big Bang theory, providing crucial evidence to support or refute it.



<h2 class="wp-block-heading" id="h-what-does-all-of-this-mean">What does all of this mean?</h2>



If the Dark Big Bang theory holds water, it could revolutionize our understanding of the universe. 



Not only would it explain the origin of dark matter, but it could also give us new insights into the early moments after the Big Bang. 



This theory highlights the importance of gravitational waves in studying the cosmos. As we get better at detecting these waves, we might uncover more secrets hidden in the universe's earliest moments.



By refining our understanding of these parameters, we might even uncover new physics that goes beyond our current theories.



The work by Ilie and Casey is a significant step in solving one of the biggest puzzles in physics. 



As future experiments provide more precise measurements, their findings could help confirm whether the Dark Big Bang is the true origin of dark matter.



The full study was published in the journal <a href="https://journals.aps.org/prd/abstract/10.1103/PhysRevD.110.103522" target="_blank" rel="noreferrer noopener">Physical Review D</a>.



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New theory called "Dark Big Bang" attempts to explain dark matter

Dark matter has always been one of the biggest mysteries...

Beautiful,Night,Landscape,,Old,Volcano,,Crater,Lake.,The,Colorful,Star

From the tiniest fluctuations after the Big Bang, gravity has orchestrated the formation of galaxies, stars, and planets, creating the vast cosmic web we see today.



Gravity isn't just what keeps us grounded -- it's been shaping the universe since its earliest days. Recent studies have provided the most precise tests of gravity on the grandest scales imaginable. 



By examining how cosmic structures have grown over the past 11 billion years, scientists have confirmed that gravity behaves just as <a href="https://www.earth.com/news/cosmic-glitch-in-gravity-expands-the-theory-of-general-relativity/" target="_blank" rel="noreferrer noopener">Einstein's theory</a> of general relativity predicts, even across billions of light-years.



<h2 class="wp-block-heading" id="h-desi-tracks-gravity-over-11-billion-years">DESI tracks gravity over 11 billion years</h2>



Pauline Zarrouk, a cosmologist at the French National Center for Scientific Research (<a href="https://www.cnrs.fr/en" target="_blank" rel="noreferrer noopener">CNRS</a>) working at the Laboratory of Nuclear and High-Energy Physics (LPNHE), has been exploring this cosmic evolution.



In collaboration with the international team behind the Dark Energy Spectroscopic Instrument (<a href="https://www.desi.lbl.gov/" target="_blank" rel="noreferrer noopener">DESI</a>), Zarrouk and her colleagues have traced how cosmic structures grew over the past 11 billion years.



Using data from DESI, the researchers provided the most precise test to date of gravity on the largest scales. 



"General relativity has been very well tested at the scale of solar systems, but we also needed to test that our assumption works at much larger scales," Zarrouk explained. 



"Studying the rate at which galaxies formed lets us directly test our theories and, so far, we're lining up with what <a href="https://www.earth.com/news/radical-new-theory-finally-unites-gravity-spacetime-and-the-quantum-realm/" target="_blank" rel="noreferrer noopener">general relativity</a> predicts at cosmological scales."



<h2 class="wp-block-heading" id="h-einstein-is-smiling-from-the-grave">Einstein is smiling from the grave</h2>



Their findings confirm that gravity behaves as Einstein's theory of general relativity predicts, even across the immense distances of the universe. 



This validation supports our leading model of the cosmos and narrows down alternative theories of gravity that have been proposed to explain puzzling observations, like the <a href="https://www.earth.com/news/universe-expansion-rate-dark-energy-measured-11-billion-years-ago/" target="_blank" rel="noreferrer noopener">accelerating expansion</a> of the universe often attributed to dark energy.



The study also sheds light on <a href="https://www.earth.com/news/quantum-gravity-search-south-pole-neutrinos-experiment/" target="_blank" rel="noreferrer noopener">neutrinos</a> -- the elusive particles that zip through space almost undetected. 



Previous experiments determined that the combined mass of the three types of neutrinos should be at least 0.059 electron volts (eV/c²). For perspective, an electron has a mass of about 511,000 eV/c². 



DESI's results suggest that the total mass of neutrinos should be less than 0.071 eV/c², tightening the constraints on these mysterious particles.



<h2 class="wp-block-heading" id="h-desi-gravity-and-cosmic-structure">DESI, gravity, and cosmic structure</h2>



"Both our BAO results and the full-shape analysis are spectacular," said Dragan Huterer, a professor at the <a href="https://umich.edu/" target="_blank" rel="noreferrer noopener">University of Michigan</a> and co-lead of DESI's group interpreting the cosmological data. 



"This is the first time that DESI has looked at the growth of cosmic structure. We're showing a tremendous new ability to probe modified gravity and improve constraints on models of <a href="https://www.earth.com/news/dark-energy-is-ripping-the-universe-apart-but-we-arent-sure-how/" target="_blank" rel="noreferrer noopener">dark energy</a>. And it's only the tip of the iceberg."



DESI is no ordinary telescope. Mounted on the Nicholas U. Mayall 4-meter Telescope at <a href="https://kpno.noirlab.edu/" target="_blank" rel="noreferrer noopener">Kitt Peak National Observatory</a>, it's capable of capturing light from 5,000 galaxies at once. 



Funded by the DOE Office of Science, the project is now in its fourth year of surveying the sky and aims to collect data from roughly 40 million galaxies and quasars by the time it's done.



<a href="https://www.earth.com/news/theory-gravity-exists-without-mass-so-dark-matter-does-not-exist/" target="_blank" rel="noreferrer noopener">Testing gravity</a> at cosmic scales is crucial. While Einstein's theory has passed every test within our solar system, there's always the possibility that it might behave differently across the vastness of space. 



By confirming that gravity acts as expected over billions of light-years, scientists can be more confident in their models of how the universe has evolved. 



<h2 class="wp-block-heading" id="h-interpreting-the-desi-data">Interpreting the DESI data</h2>



<a href="https://profiles.utdallas.edu/mishak">Dr. Mustapha Ishak-Boushaki</a>, a professor of physics in the <a href="https://nsm.utdallas.edu/">School of Natural Sciences and Mathematics</a> at UT Dallas, co-led the DESI working group that interpreted the cosmological data.



“For this round of DESI results, I focused my efforts at UT Dallas on conducting a large part of the analysis on gravity, which puts constraints on how matter in the universe moves and how large-scale structures, such as clusters of galaxies, evolve,” explained Ishak-Boushaki. 



“The results from DESI, combined with datasets from other experiments, are consistent with general relativity theory operating at cosmic scales, although they do not completely exclude other theories of <a href="https://www.earth.com/news/central-theory-of-quantum-gravity-is-modeled-in-the-laboratory/" target="_blank" rel="noreferrer noopener">modified gravity</a>.”



The new results provide an extended analysis of <a href="https://news.utdallas.edu/science-technology/desi-findings-2024/" target="_blank" rel="noreferrer noopener">DESI’s first year of data</a>, which in April contributed to the largest 3D map of the universe to date and revealed hints that <a href="https://newscenter.lbl.gov/2024/04/04/desi-first-results-make-most-precise-measurement-of-expanding-universe/" target="_blank" rel="noreferrer noopener">dark energy might be evolving</a> over time.



“The latest analysis is also consistent with our previous findings that give preference to the theory that <a href="https://www.earth.com/news/dark-energy-could-explain-the-rapid-expansion-of-the-early-universe/" target="_blank" rel="noreferrer noopener">dark energy</a> is not constant, but dynamic, which is a very important result for cosmic acceleration,” Ishak-Boushaki said.



<h2 class="wp-block-heading" id="h-how-did-this-happen">How did this happen?</h2>



The collaboration is currently analyzing data from the first three years and expects to present updated measurements of <a href="https://www.earth.com/news/new-evidence-suggests-that-dark-energy-comes-from-black-holes/" target="_blank" rel="noreferrer noopener">dark energy</a> and the universe's expansion history by spring 2025. 



The recent results align with earlier hints that dark energy might be evolving over time, adding to the excitement for what's to come.



"Dark matter makes up about a quarter of the universe, and dark energy makes up another 70 percent, and we don't really know what either one is," said Mark Maus, a PhD student at <a href="https://www.lbl.gov/" target="_blank" rel="noreferrer noopener">Berkeley Lab</a> and UC Berkeley who worked on theory and validation modeling pipelines for the new analysis. 



"The idea that we can take pictures of the universe and tackle these big, fundamental questions is mind-blowing."



The study utilized nearly 6 million <a href="https://www.earth.com/news/lonely-quasars-in-the-early-universe-cannot-be-explained/" target="_blank" rel="noreferrer noopener">galaxies and quasars</a>, allowing researchers to peer up to 11 billion years into the past. 



<h2 class="wp-block-heading" id="h-what-s-next-for-desi-and-gravity">What's next for DESI and gravity?</h2>



To sum it all up, with just one year of data, DESI has made the most precise overall measurement of the growth of cosmic structures, surpassing previous efforts that took decades.



The DESI project is remarkable not just for its technological capabilities but also for its collaborative spirit. 



With over 900 researchers from more than 70 institutions worldwide, it's a testament to what can be achieved when the global scientific community comes together.



As we await the next round of results, one can't help but wonder: What other secrets of the universe are waiting to be uncovered? 



The quest to understand gravity, dark matter, and dark energy continues, and each new discovery brings us a little closer to unraveling the mysteries of the cosmos.



The full study was published in <a href="https://data.desi.lbl.gov/doc/papers/">several scientific journals</a>.



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New gravity discovery is called 'mind-blowing' and proves Einstein right once again

From the tiniest fluctuations after the Big Bang, gravity has...

In the journey of aging, the road is often marked by unexpected detours. Some are joyful, such as the birth of a grandchild or new opportunities for personal growth. Others, like the onset of health conditions, can be less than welcome. 



Among these, dementia is a ghost that haunts the corridors of our golden years. But new research sheds light on a surprising source of cognitive protection. 



The study reveals that the quality of our sleep affects the likelihood of developing dementia.



<h2 class="wp-block-heading" id="h-understanding-sleep-stages">Understanding sleep stages</h2>



Our sleep isn't just one long, uninterrupted state -- it's actually made up of different stages. We start off in Stage 1, a light sleep where we're drifting in and out and can be woken up easily. 



Then we move into Stage 2, where our body temperature drops and our heart rate begins to slow. It's a bit deeper than Stage 1, but we're still not in the deepest sleep yet.



Next, we enter Stage 3, also known as deep sleep or slow-wave sleep. This is the stage where our body does most of its repair work, like healing tissues and building bone and muscle. 



Finally, we hit REM (Rapid Eye Movement) sleep. This is the stage where most of our dreaming happens, and our brains are almost as active as when we're awake, but our muscles are pretty much paralyzed. 



Throughout the night, we cycle through these stages multiple times, which is essential for feeling rested and rejuvenated.



<h2 class="wp-block-heading" id="h-power-of-slow-wave-sleep">Power of slow-wave sleep</h2>



<a href="https://www.earth.com/news/sleeping-more-on-weekends-can-reduce-heart-disease-risk/" target="_blank" rel="noreferrer noopener">Sleep</a> is not just a monolithic block of inactivity that we schedule into our 24-hour days. It's a rhythmic cycle, subdivided into stages, each with its unique characteristics and functions. 



Among these, slow-wave sleep plays a starring role.



Slow-wave sleep is the third phase within the typical 90-minute sleep cycle, lasting roughly 20 to 40 minutes.



Think of it as the deep, rejuvenating spa bath of sleep. Your physiological processes and cognitive systems get a thorough pampering during this time. 



But what benefits does this "spa treatment" bring to our bodies and minds?



Slow-wave sleep serves as a crucial health booster. It helps strengthen our muscles, bones, and immune system, and primes our brains for new learning.



Remarkably, a 2023 study revealed that Alzheimer's patients showed improved memory performance after a healthy dose of slow-wave sleep.



<h2 class="wp-block-heading" id="h-linking-sleep-and-dementia">Linking sleep and dementia</h2>



Neuroscientist Matthew Pase of <a href="https://search.app?link=https%3A%2F%2Fwww.monash.edu%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">Monash University</a> has been examining the inner workings of sleep's deepest stage.



"Slow-wave sleep, or deep <a href="https://www.earth.com/news/world-sleep-day-2024-the-quest-for-a-well-rested-society/" target="_blank" rel="noreferrer noopener">sleep</a>, supports the aging brain in many ways, and we know that sleep augments the clearance of metabolic waste from the brain, including facilitating the clearance of proteins that aggregate in Alzheimer's disease," said Pase.



So, not only does slow-wave sleep flex our memory muscles, but it also helps keep our brains tidier and healthier. But where does dementia fit into this story?



<h2 class="wp-block-heading" id="h-sleep-dementia-connection">Sleep-dementia connection</h2>



To investigate the correlation between dementia and slow-wave <a href="https://www.earth.com/news/wake-up-in-your-dreams-exploring-the-world-of-lucid-dreaming-sleep-science/" target="_blank" rel="noreferrer noopener">sleep</a>, Pase and an international team of researchers scrutinized the records of 346 participants from the <a href="https://www.framinghamheartstudy.org/" target="_blank" rel="noreferrer noopener">Framingham Heart Study</a>.



In particular, the team analyzed data from two sleep studies conducted over a space of approximately five years. 



This unique dataset, featuring older adults with no initial records of dementia, presented an unrivaled opportunity.



Across the 17-year monitoring period, 52 dementia cases were reported. The analysis showed that those who had recorded a decrease in slow-wave sleep were 27 percent more likely to develop dementia.



<h2 class="wp-block-heading" id="h-decrease-in-slow-wave-sleep">Decrease in slow-wave sleep</h2>



As the researchers burrowed deeper, they noticed something peculiar. Starting around the age of 60, the rate of slow-wave sleep began to drop, peaking between 75 and 80, and then leveling off. 



Upon comparing the results of the first and second sleep studies, a correlation emerged. Each percentage point decrease in slow-wave sleep per year was associated with an increase in dementia risk of 27 percent.



And when the focus shifted to Alzheimer's disease, the most common form of dementia, the risk jumped to 32 percent.



<h2 class="wp-block-heading" id="h-additional-health-impacts">Additional health impacts</h2>



Now, let's take a step back and look at the broader specter of <a href="https://www.earth.com/news/poor-sleep-habits-may-age-the-brain-faster/" target="_blank" rel="noreferrer noopener">health</a>. 



The Framingham Heart Study also tracks other health markers, such as cardiovascular disease risk factors and loss of hippocampal volume, which is an early indicator of Alzheimer's.



Lower slow-wave sleep levels seemed to indicate a greater hazard of cardiovascular disease, use of sleep-impacting medications, and the presence of the APOE ε4 gene, a notorious accomplice in Alzheimer's.



<h2 class="wp-block-heading" id="h-future-of-sleep-and-dementia-research">Future of sleep and dementia research</h2>



Even though the study has unearthed some compelling insights, it's essential to treat these findings as signposts rather than destinations. The researchers do not claim that a reduction in slow-wave sleep directly induces dementia.



Rather, they propose that dementia-related brain processes might cause sleep loss. To fully comprehend and validate these factors, additional research is needed.



In the meantime, one thing is clear - there's no harm in getting plenty of rest. Quality sleep does a lot more than just refreshing your brain and body; it could potentially be a shield against rampant health issues, including dementia.



The in-depth findings of this study have been published in <a href="https://jamanetwork.com/journals/jamaneurology/fullarticle/2810957" target="_blank" rel="noreferrer noopener">JAMA Neurology.</a>



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One particular sleep stage does more to protect the brain from dementia

In the journey of aging, the road is often marked...

Remember when your mom advised you to eat dinner early? Turns out, she was right all along. A recent study by scientists from the Universitat Oberta de Catalunya (UOC) and Columbia University found evidence that backs up this age-old wisdom.



The study, published in the open access Nature group journal Nutrition &amp; Diabetes, suggests that consuming over 45% of our daily calorie intake after 5 p.m. can lead to increased glucose levels. 



This uptick in glucose carries potential health risks, irrespective of a person's weight or body fat levels.



<h2 class="wp-block-heading" id="h-meal-time-and-glucose-levels">Meal time and glucose levels</h2>



The experiment was conducted at <a href="https://www.columbia.edu" target="_blank" rel="noreferrer noopener">Columbia University</a>'s Irving Medical Center in New York, under the guidance of Dr. Diana Díaz-Rizzolo, a postdoctoral researcher and member of the Faculty of Health Sciences at the <a href="https://www.uoc.edu/en" target="_blank" rel="noreferrer noopener">UOC</a>.



"Maintaining high levels of <a href="https://www.earth.com/news/glucose-the-sweet-secret-to-a-younger-brain/" target="_blank" rel="noreferrer noopener">glucose</a> over long periods of time can have implications including a higher risk of progressing to type 2 diabetes, an increase in cardiovascular risk due to the damage that high glucose levels do to blood vessels, and increased chronic inflammation, which aggravates cardiovascular and metabolic damage," noted Dr. Díaz-Rizzolo.



Until now, it was commonly believed that the primary repercussion of late dinners was weight gain, mostly because people tend to opt for unhealthy, ultra-processed foods at night.



<h2 class="wp-block-heading" id="h-timing-of-meals">Timing of meals</h2>



However, the importance of this study lies in its ability to demonstrate that the timing of our meals can independently affect <a href="https://www.earth.com/news/type-2-diabetes-heightens-alzheimers-risk/" target="_blank" rel="noreferrer noopener">glucose</a> metabolism, regardless of the number of calories consumed throughout the day or an individual's weight and body fat level.



For their research, the team examined 26 individuals aged between 50 and 70, who were either overweight or obese and had prediabetes or type 2 diabetes. 



They divided the participants into two groups: early eaters who consumed the majority of their daily calories before evening, and late eaters who consumed 45% or more of their calories after 5 p.m. 



Despite both groups consuming the same amount of calories and the same types of food, their meal <a href="https://www.earth.com/news/meal-timing-has-a-major-influence-on-our-health/" target="_blank" rel="noreferrer noopener">timings</a> were different.



Intriguingly, it was found that late eaters had poorer glucose tolerance despite their weight or diet composition. They also tended to consume larger quantities of carbohydrates and fats in the evening.



<h2 class="wp-block-heading" id="h-why-late-eating-affects-glucose">Why late eating affects glucose</h2>



Dr. Díaz Rizzolo, an expert on obesity, diabetes, and aging-related topics, explained the science behind this.



"The body's ability to metabolize glucose is limited at night, because the secretion of insulin is reduced, and our cells' sensitivity to this hormone declines due to the circadian rhythm, which is determined by a central clock in our brain that is coordinated with the hours of daylight and night." 



<h2 class="wp-block-heading" id="h-cultural-considerations">Cultural considerations</h2>



It's important to recognize how meal timing varies across cultures, as dietary habits differ widely. For example, Mediterranean cultures often have their largest meal in the late afternoon, while Northern Europeans eat dinner early. 



Adapting dietary advice to fit these cultural contexts can improve its effectiveness. Future research should explore how considering cultural, environmental, and social factors in dietary guidance could boost adherence and results, thereby improving global public health.



By understanding meal timing in cultural contexts, dietary recommendations can better fit diverse habits worldwide.



<h2 class="wp-block-heading" id="h-the-path-to-a-healthier-lifestyle">The path to a healthier lifestyle</h2>



This study reveals an essential aspect of our daily nutrition - the timing of our meals.



"Until now, personal decisions in nutrition have been based on two main questions: how much we eat, and what foods to choose. With this study, a new factor in cardiometabolic health is beginning to become increasingly important: when we eat," concluded Dr. Díaz-Rizzolo.



The path to a healthier lifestyle, according to the results of this study, should include a focus on eating the bulk of our <a href="https://www.earth.com/news/what-you-eat-can-literally-change-the-world/" target="_blank" rel="noreferrer noopener">food</a> during daylight hours. 



"The highest levels of calorie intake during the day should be at breakfast and lunch, instead of at teatime and dinner," said Dr. Díaz-Rizzolo.



She also recommends avoiding ultra-processed products, fast food, and carbohydrate-rich foods - especially at night.



While more research is needed to explore the implications of this study further, the results thus far provide food for thought on meal timing and cardiometabolic health.



The study is published in the journal <a href="https://www.nature.com/articles/s41387-024-00347-6" target="_blank" rel="noreferrer noopener">Nutrition and Diabetes</a>.



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Meal timing has a major influence on our health

Remember when your mom advised you to eat dinner early?...

Pterosaurs, the extinct flying reptiles that soared alongside dinosaurs, are among the most intriguing creatures in Earth's history.&nbsp;



While some later species reached wingspans of up to 10 meters, early pterosaurs were significantly smaller, typically limited to around two meters.&nbsp;



Now, a newly described species, Skiphosoura bavarica, sheds light on the evolutionary steps that allowed these creatures to bridge this size gap and adopt advanced anatomical features.&nbsp;



The discovery, led by David Hone of <a href="https://www.qmul.ac.uk/" target="_blank" rel="noreferrer noopener">Queen Mary University of London</a>, represents a rare find that enhances our understanding of pterosaur <a href="https://www.earth.com/news/pterosaurs-mastered-land-before-dominating-the-sky/" target="_blank" rel="noreferrer noopener">evolution</a>.



<h2 class="wp-block-heading" id="h-a-pterosaur-fossil-unlike-any-other">A pterosaur fossil unlike any other</h2>



The name Skiphosoura bavarica translates to “sword tail from Bavaria,” reflecting its distinctive stiff, pointed tail and the southern German region where it was unearthed.&nbsp;



What makes this fossil truly remarkable is its state of preservation. Nearly every bone of the animal has been recovered, and unlike most pterosaur fossils, which are typically flattened, this specimen is preserved in three dimensions.&nbsp;



With a wingspan of about two meters - comparable to a golden eagle - Skiphosoura provides a rare glimpse into the morphology of transitional pterosaurs.



“This is an incredible find. It really helps us piece together how these amazing <a href="https://www.earth.com/news/secrets-of-flight-feathers-may-reveal-which-dinosaurs-could-fly/" target="_blank" rel="noreferrer noopener">flying animals</a> lived and evolved. Hopefully this study will be the basis for more work in the future on this important evolutionary transition,” Hone said.



<h2 class="wp-block-heading" id="h-broad-classification-of-pterosaur-fossils-nbsp">Broad classification of pterosaur fossils&nbsp;</h2>



For over 200 years, scientists have classified pterosaurs into two primary groups. Non-pterodactyloids were early pterosaurs with small heads, short necks, long tails, a short bone in their wing wrists, and a long fifth toe on their feet.



Pterodactyloids were a later species characterized by large heads, long necks, short tails, elongated wrist bones, and a short fifth toe.



While this broad classification was useful, it left significant gaps in understanding how pterosaurs transitioned between these forms. The discovery of in the 2010s helped address some of these questions.&nbsp;



These intermediate species revealed that the head and neck adapted first, with other anatomical changes following later. However, scientists were left wondering what occurred immediately before and after the darwinopterans.



<h2 class="wp-block-heading" id="h-bridging-the-evolutionary-gap">Bridging the evolutionary gap</h2>



Skiphosoura bavarica offers vital clues. Evolutionarily, it stands between darwinopterans and pterodactyloids, displaying a combination of features from both groups.&nbsp;



It possesses the pterodactyloid-like head and neck characteristic of darwinopterans but also exhibits advancements such as a lengthened wrist, a shorter fifth toe, and a reduced tail - though not as pronounced as in later pterodactyloids.



This discovery, combined with a newly reconstructed evolutionary tree, allows researchers to trace the progression of anatomical changes in pterosaurs.&nbsp;



The study also places the Scottish pterosaur Dearc as a transitional species between early pterosaurs and darwinopterans.&nbsp;



Together, Dearc and Skiphosoura complete a nearly unbroken sequence of evolutionary adaptations, providing a step-by-step account of how pterosaurs evolved into the large, advanced forms seen in the later pterodactyloids.



<h2 class="wp-block-heading" id="h-adaptations-for-larger-sizes">Adaptations for larger sizes</h2>



Interestingly, both Dearc and Skiphosoura are unusually large compared to other species of their time.&nbsp;



This suggests that the adaptations that enabled pterodactyloids to achieve enormous sizes - such as larger heads and longer necks - began appearing in transitional forms like Skiphosoura.&nbsp;



These changes likely offered advantages such as improved flight capabilities and more efficient <a href="https://www.earth.com/news/fish-foraging-behavior-changing-climate-warming-waters/" target="_blank" rel="noreferrer noopener">foraging</a>.



<h2 class="wp-block-heading" id="h-analyzing-the-pterosaur-fossil-nbsp">Analyzing the pterosaur fossil&nbsp;</h2>



The fossil preparation and analysis were feats of modern technology and expertise. Unlike typical flattened fossils, the three-dimensional preservation of Skiphosoura required meticulous work.&nbsp;



“As a preparator, I have worked on more than 60 pterosaur specimens from Solnhofen limestone,” said study co-author Stefan Selzer, who prepared the specimen.



“I recognized during the final prep this specimen showed features that combined characteristics of both major groups of pterosaurs, with the shortened tail as the most important diagnostic feature.”&nbsp;



Digital imaging also played a critical role in analyzing the fossil.&nbsp;



René Lauer of the <a href="https://www.lauerfoundationpse.org/" target="_blank" rel="noreferrer noopener">Lauer Foundation for Paleontology, Science, and Education</a> explained: “The specimen was disarticulated with bones of varying quality often overlaid upon one another.”&nbsp;



“Digital photography of the specimen taken in both visible and UV light significantly aided in the process to identify these elements and to better analyze finer details that were not discernible in normal daylight alone.”



<h2 class="wp-block-heading" id="h-redefining-pterosaur-evolution">Redefining pterosaur evolution</h2>



The discovery of Skiphosoura bavarica provides a detailed roadmap of pterosaur evolution, offering insights into how these creatures developed the traits that would eventually enable them to dominate the skies.&nbsp;



By clarifying the sequence of anatomical changes, this fossil represents a major milestone in understanding the evolutionary history of pterosaurs.



“Pterosaurs have long been symbols of the unique life of the past. Skiphosoura represents an important new form for working out pterosaur evolutionary relationships and by extension how this lineage arose and changed,” said co-author Adam Fitch, a paleontologist at the <a href="https://www.wisc.edu/" target="_blank" rel="noreferrer noopener">University of Wisconsin-Madison</a>.



As researchers continue to study this exceptional find, they hope to uncover even more details about how pterosaurs adapted and thrived in prehistoric <a href="https://www.earth.com/news/ecosystem-behavior-earth-first-sea-creatures-stirring-water-drove-evolution/" target="_blank" rel="noreferrer noopener">ecosystems</a>.&nbsp;



“This is an incredible find. It really helps us piece together how these amazing flying animals lived and evolved,” Hone said.



With Skiphosoura bavarica, scientists have a clearer view of the evolutionary journey that transformed small, early pterosaurs into the majestic flying reptiles of the Mesozoic era, cementing its role as a key link in the story of life on Earth.



The research is published in the journal <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(24)01377-0" target="_blank" rel="noreferrer noopener">Current Biology</a>.



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New fossil fills crucial gap in pterosaur evolution

Pterosaurs, the extinct flying reptiles that soared alongside dinosaurs, are...

Acupuncture, ketamine infusions, and electroconvulsive therapy are just a few of the options available for individuals diagnosed with Major Depressive Disorder (MDD) and Treatment-Resistant Depression (TRD). These treatments, while potentially effective, can often feel daunting or expensive. 



Now, research from <a href="https://www.emory.edu/home/index.html" target="_blank" rel="noreferrer noopener">Emory University</a> suggests that psilocybin-assisted therapy (PSIL-AT), using the active ingredient in hallucinogenic mushrooms, could provide transformative benefits to more than five million people in the U.S., pending <a href="https://www.fda.gov/" target="_blank" rel="noreferrer noopener">FDA</a> approval.



The study highlights the urgent need for therapies featuring <a href="https://www.earth.com/news/how-psilocybin-mushrooms-got-their-magic/" target="_blank" rel="noreferrer noopener">psilocybin</a> while addressing the logistical and economic considerations that policymakers, insurance providers, and public health agencies will face in making such treatments widely accessible.



<h2 class="wp-block-heading" id="h-millions-could-benefit-from-psilocybin-therapy">Millions could benefit from psilocybin therapy</h2>



Using national data on individuals currently being treated for MDD and TRD, Emory researchers applied exclusionary criteria to identify those who would be medically eligible for PSIL-AT.&nbsp;



Factors such as comorbidities, including mania, <a href="https://www.earth.com/news/living-close-to-bars-and-pubs-increases-the-risk-of-heart-failure/" target="_blank" rel="noreferrer noopener">heart failure</a>, and diabetes, were used to refine the eligible population.



The analysis revealed that 56 to 62% of patients with MDD and TRD - approximately 5.1 to 5.6 million people - could benefit from this therapy.



Study lead author Fayzan Rab is an M.D. candidate at Emory University’s School of Medicine.&nbsp;



“This information is significant because much of the current focus on psychedelic therapies is about its efficacy within clinical trials, and very few people are studying what would be the broader implications of implementing these novel therapeutics,” said Rab.&nbsp;



“Our study is one of the first to look at the bigger <a href="https://www.earth.com/news/living-alone-in-america-an-escalating-public-health-crisis/" target="_blank" rel="noreferrer noopener">public health</a> and economic consequences of a world where psilocybin therapy is made more available to Americans.”



<h2 class="wp-block-heading" id="h-actionable-data-for-fda-consideration">Actionable data for FDA consideration</h2>



Psilocybin-assisted therapy is currently designated as a breakthrough therapy by the FDA, allowing for an expedited review of Phase III clinical trial results due to its potential to address <a href="https://www.earth.com/news/confirmed-magic-mushrooms-can-effectively-treat-depression/" target="_blank" rel="noreferrer noopener">depression</a>.&nbsp;



The findings from this study provide actionable data to inform the FDA’s decision-making process.



“What is really timely about this research is that it provides a data-driven number that is interpretable to the FDA,” Rab said.&nbsp;



“This is how many Americans we think are at stake. I think that will be a meaningful estimate for the FDA to weigh when they consider whether to approve psilocybin for therapeutic use.”



<h2 class="wp-block-heading" id="h-insurance-coverage-and-psilocybin-therapy-demand">Insurance coverage and psilocybin therapy demand</h2>



If approved, the availability of PSIL-AT will be heavily influenced by decisions from private and public insurance providers, including the <a href="https://www.cms.gov/" target="_blank" rel="noreferrer noopener">Centers for Medicare &amp; Medicaid Services</a> (CMS).&nbsp;



According to the study, nearly 20% of Medicaid’s 85 million beneficiaries - approximately 17 million people - are likely to have clinical depression. How Medicaid and other insurers decide to reimburse for psilocybin-assisted therapy will significantly impact its accessibility and demand.



<h2 class="wp-block-heading" id="h-fast-acting-relief-from-psilocybin-nbsp">Fast-acting relief from psilocybin&nbsp;</h2>



One notable advantage of psilocybin therapy is its rapid efficacy. Previous clinical trials have shown that a single 25 mg dose of psilocybin can substantially reduce symptoms of depression.&nbsp;



Dr. George Grant, co-director of Emory University’s <a href="https://psychedelics.emory.edu/" target="_blank" rel="noreferrer noopener">Center for Psychedelics and Spirituality</a> (ECPS), emphasized the potential cost savings for the healthcare system.



“Psychedelic medicines have promise because the intervention is so fast-acting, whereas right now, insurance providers and payers often need to fund the use of antidepressants throughout their lives,” said Grant, who is also the executive director for Spiritual Health at the <a href="https://whsc.emory.edu/" target="_blank" rel="noreferrer noopener">Woodruff Health Sciences Center</a>.



This quick-acting treatment could alleviate the financial burden on both insurers and patients while delivering significant relief for those with depression.



<h2 class="wp-block-heading" id="h-holistic-approach-to-mental-and-spiritual-wellness">Holistic approach to mental and spiritual wellness</h2>



Supported by Emory University’s ECPS, the study integrates clinical psychiatry with spiritual health to explore the therapeutic potential of psychedelic medicines. The center aims to foster a deeper understanding of how psychedelics can bring patients to a state of mental and spiritual wellness.



“Coming to the aid of people who are suffering is very important, and psilocybin-assisted therapy could help people arrive at a place of satisfaction within themselves so that their lives achieve optimal meaning and purpose,” Grant said.



Rab also highlighted the impartial academic environment in which the research was conducted, stressing that it was independent of pharmaceutical influence.&nbsp;



“I am glad to be supported by the Center for Psychedelics and Spirituality, which is an academic environment, providing an objective third-party perspective to policymakers, the FDA, and public health agencies,” Rab said.&nbsp;



“I am really hopeful that continued research in the area of psychedelic medicine and therapeutics could benefit the millions of Americans that might qualify for it.”



<h2 class="wp-block-heading" id="h-a-path-forward-for-psilocybin-therapy">A path forward for psilocybin therapy</h2>



The study provides a roadmap for the potential rollout of psilocybin-assisted therapy, offering actionable insights for healthcare providers, insurers, and policymakers.&nbsp;



By addressing the needs of millions of Americans suffering from MDD and TRD, PSIL-AT could represent a paradigm shift in the treatment of depression, bridging clinical efficacy with accessible and holistic care.



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Psilocybin therapy offers hope for millions with depression

Acupuncture, ketamine infusions, and electroconvulsive therapy are just a few...

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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



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Flu viruses are more flexible than expected

[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"] Today's Video of the Day from the...

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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

[sendtonews key="LvS8v8bp9z-2564889-12187" type="single"] Today's Video of the Day from the...

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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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Today’s Video of the Day from <a href="https://www.igb.illinois.edu/">Carl R. Woese Institute for Genomic Biology</a> reveals how scientists can modify common crops like soybean, rice, and wheat to protect them from heat stress.



“We need to double crop production by 2050 to feed a growing global population, and not only are we not on track to do that, but climate change is further complicating things,” said Amanda Cavanagh, a lecturer at the University of Essex. 



The study is part of Realizing Increased Photosynthetic Efficiency (RIPE), an international research project that aims to develop food crops that turn the sun’s energy into food more efficiently.



“Using an engineering approach we designed multiple alternative metabolic pathways to photorespiration. Testing them in the field showed increases in productivity which led Amanda to significantly move the project forward by showing our engineered plants can withstand pretty extreme temperature stress,” said study co-author and RIPE researcher Paul South.&nbsp;



“As the climate changes and temperature stresses increase the pressure on our global food supply, farmers will need every tool available including engineering approaches like the synthetic biology used here to maintain safe and productive harvests.”



The experts tested plants modified to have more efficient photorespiration to see if they were better adapted to warmer temperatures.&nbsp;



The team found that the engineered plants produced 26 percent more biomass than the wild-type plants exposed to the same temperatures, and had 15 percent less yield loss under the higher temperatures.



Video Credit: Amanda Nguyen/University of Illinois



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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.

Designing crops that can beat the heat

[sendtonews key="QGPzYnXEtN-1712599-12187" type="single"] Today’s Video of the Day from Carl...

Historic rainfall in Pakistan has caused deadly flooding. Today&#8217;s Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> shows devastating flooding across the Sindh province in southeastern Pakistan, where historic amounts of rain has fallen in recent weeks. 
The record-breaking monsoon season has claimed hundreds of lives and destroyed more than 200,000 homes since June.
The Pakistan Meteorological Department also reported that nearly one million acres of crops have been destroyed by the flooding, including cotton, vegetables, onions, tomatoes, and sugarcane. Historic rainfall in Pakistan has caused deadly flooding
The image was captured on September 21, 2020 by the Moderate Resolution Imaging Spectroradiometer (MODIS) on<a href="https://www.bing.com/search?q=nasa&amp;cvid=c29840309817465c914d6f0f53e79d71&amp;FORM=ANAB01&amp;PC=HCTS"> NASA’s</a> Terra satellite. Historic rainfall in Pakistan has caused deadly flooding. Pakistan, officially the Islamic Republic of Pakistan,  is a country in <a title="South Asia" href="https://en.wikipedia.org/wiki/South_Asia">South Asia</a>. It is the world&#8217;s fifth-most populous country with a population exceeding 212.2 million. It has the world&#8217;s second-largest Muslim population. It is the 33rd-largest country by area, spanning 881,913 square kilometres (340,509 square miles). Pakistan has a 1,046-kilometre (650-mile) <a class="mw-redirect" title="Coastline" href="https://en.wikipedia.org/wiki/Coastline">coastline</a> along the Arabian Sea and <a title="Gulf of Oman" href="https://en.wikipedia.org/wiki/Gulf_of_Oman">Gulf of Oman</a> in the south and is bordered by <a title="India" href="https://en.wikipedia.org/wiki/India">India</a> to the east, Afghanistan to the west, <a title="Iran" href="https://en.wikipedia.org/wiki/Iran">Iran</a> to the southwest, and <a title="China" href="https://en.wikipedia.org/wiki/China">China</a> to the northeast. It is separated narrowly from <a title="Tajikistan" href="https://en.wikipedia.org/wiki/Tajikistan">Tajikistan</a> by Afghanistan&#8217;s <a title="Wakhan Corridor" href="https://en.wikipedia.org/wiki/Wakhan_Corridor">Wakhan Corridor</a> in the northwest, and also shares a maritime border with Oman.
Image Credit: NASA Earth Observatory 
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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

Historic rainfall in Pakistan has caused deadly flooding

Lake Milh in central Iraq. Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features one of Iraq’s largest lakes, Lake Milh, which has been fluctuating in recent decades as a result of dam management and droughts.

The photograph shows that Lake Milh - also known as Lake Razzaza - is finally starting to fill up again.

In the 1980s, Lake Milh was a popular recreational area, as well as an important breeding ground for many birds such as flamingos. In the following years, however, water levels began to disappear along with tourism and several fish species. Lake Milh in central Iraq

The image was captured on August 21, 2020 by the Operational Land Imager (OLI) on Landsat 8.Iraq has a coastline measuring 58 km (36 miles) on the northern <a title="Persian Gulf" href="https://en.wikipedia.org/wiki/Persian_Gulf">Persian Gulf</a> and encompasses the Mesopotamian Alluvial Plain, the northwestern end of the Zagros mountain range and the eastern part of the <a title="Syrian Desert" href="https://en.wikipedia.org/wiki/Syrian_Desert">Syrian Desert</a>. Two major rivers, the <a title="Tigris" href="https://en.wikipedia.org/wiki/Tigris">Tigris</a> and <a title="Euphrates" href="https://en.wikipedia.org/wiki/Euphrates">Euphrates</a>, run south through Iraq and into the <a title="Shatt al-Arab" href="https://en.wikipedia.org/wiki/Shatt_al-Arab">Shatt al-Arab</a> near the <a title="Persian Gulf" href="https://en.wikipedia.org/wiki/Persian_Gulf">Persian Gulf</a>. These rivers provide Iraq with significant amounts of fertile land. The region between the Tigris and Euphrates rivers, historically known as Mesopotamia, is often referred to as the cradle of civilisation. It was here that mankind first began to read, write, create laws and live in cities under an organised government—notably <a title="Uruk" href="https://en.wikipedia.org/wiki/Uruk">Uruk</a>, from which "Iraq" is derived. The area has been home to successive civilisations since the 6th millennium BC. Iraq was the centre of the <a title="Akkadian Empire" href="https://en.wikipedia.org/wiki/Akkadian_Empire">Akkadian</a>, <a title="Third Dynasty of Ur" href="https://en.wikipedia.org/wiki/Third_Dynasty_of_Ur">Sumerian</a>, <a title="Neo-Assyrian Empire" href="https://en.wikipedia.org/wiki/Neo-Assyrian_Empire">Assyrian</a> and <a title="Neo-Babylonian Empire" href="https://en.wikipedia.org/wiki/Neo-Babylonian_Empire">Babylonian</a> empires

Image Credit: NASA Earth Observatory 

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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