Today's Image of the Day from the European Space Agency features the galaxy I Zwicky 18, which was captured in remarkable detail by the James Webb Space Telescope.



I Zwicky 18 is a blue compact dwarf <a href="https://www.earth.com/news/newly-discovered-stars-milky-way-are-old-as-universe/" target="_blank" rel="noreferrer noopener">galaxy</a> located approximately 59 million light-years away in the constellation Ursa Major.&nbsp;



<h2 class="wp-block-heading" id="h-star-formation-in-i-zwicky-18">Star formation in I Zwicky 18</h2>



The galaxy is notable for its relatively young appearance and the fact that it contains very few heavy elements. These characteristics indicate that it has experienced little <a href="https://www.earth.com/news/baby-stars-release-sneezes-of-gas-and-dust-as-they-develop/" target="_blank" rel="noreferrer noopener">star formation</a> compared to other galaxies of similar age.



“The galaxy was first identified by Swiss astronomer Fritz Zwicky in the 1930’s and resides roughly 59 million light-years from Earth,” noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>. “This galaxy has gone through several sudden bursts of star formation.”&nbsp;



According to ESA, I Zwicky 18 is typical of the kinds of galaxies that inhabited the early universe and is much smaller than our <a href="https://www.earth.com/news/runaway-star-j1249-36-spotted-trying-to-escape-our-milky-way-galaxy/" target="_blank" rel="noreferrer noopener">Milky Way</a>.



<h2 class="wp-block-heading" id="h-webb-telescope-image-of-the-galaxy">Webb telescope image of the galaxy</h2>



“Two major starburst regions are embedded in the heart of the galaxy. The wispy brown filaments surrounding the central starburst region are bubbles of gas that have been heated by stellar winds and intense ultraviolet radiation unleashed by hot, young stars,” said ESA.



“A companion galaxy resides nearby to the dwarf galaxy, which can be seen at the bottom of the wider-field image. The companion may be interacting with the dwarf galaxy and may have triggered that galaxy's recent star formation.”&nbsp;



ESA explained that the “orange blobs” surrounding the galaxy are the dim glow from ancient fully formed galaxies at much larger distances.



<h2 class="wp-block-heading" id="h-key-characteristics-of-i-zwicky-18">Key characteristics of I Zwicky 18</h2>



As previously mentioned, the galaxy has a very low abundance of elements heavier than hydrogen and helium, suggesting that it has not undergone significant stellar processing.



<h3 class="wp-block-heading" id="h-young-stellar-population-nbsp">Young stellar population&nbsp;</h3>



Despite its old age, I Zwicky 18 contains many young, hot stars. This suggests that it might have experienced a burst of <a href="https://www.earth.com/news/hubble-detects-awe-inspiring-newborn-star/" target="_blank" rel="noreferrer noopener">star formation</a> relatively recently in its history.



<h3 class="wp-block-heading" id="h-interstellar-medium-nbsp">Interstellar medium&nbsp;</h3>



The galaxy has a high density of gas, which is a prime ingredient for star formation. This gas is mostly in the form of hydrogen.



<h3 class="wp-block-heading" id="h-unusual-characteristics">Unusual characteristics</h3>



Its characteristics are more typical of primordial galaxies found in the early universe, making it a valuable object of study for understanding galaxy formation and evolution.



Ultimately, I Zwicky 18 provides insights into the conditions and processes that might have been prevalent in the early universe.



<h3 class="wp-block-heading" id="h-life-cycles-of-stars-and-dust">Life cycles of stars and dust</h3>



The image was captured as part of a Webb program to study the life cycle of dust in I Zw 18.&nbsp;



“Scientists are now building off of previous research with Hubble obtained at optical wavelengths, studying individual dusty stars in detail with Webb’s equivalent spatial resolution and sensitivity at infrared wavelengths.”&nbsp;



ESA noted that this galaxy is of particular interest as its content of elements heavier than helium is one of the lowest of all known <a href="https://www.earth.com/news/early-galaxy-formation-occurred-much-faster-than-we-thought/" target="_blank" rel="noreferrer noopener">galaxies</a> in the local universe.&nbsp;



“Such conditions are thought to be similar to those in some of the first star-forming galaxies at high redshift, so the Webb study of I Zw 18 should shed light on the life-cycle of stars and dust in the early universe.”



<h2 class="wp-block-heading" id="h-the-constellation-ursa-major">The constellation Ursa Major </h2>



Ursa Major, also known as the Great Bear, is one of the most prominent and easily recognizable constellations in the northern sky. 



Its name, "Ursa Major," means "Great Bear" in Latin, and it has been a significant part of various mythologies and star lore across cultures for thousands of years. 



One of the most famous asterisms within Ursa Major is the Big Dipper, a group of seven bright stars that form a shape resembling a ladle or dipper. The Big Dipper is often used as a navigation tool because it points to Polaris, the North Star, located in the nearby constellation Ursa Minor.



Ursa Major is best viewed in the northern hemisphere and is circumpolar, meaning it is visible year-round for much of the Northern Hemisphere. Its position changes with the seasons, rotating around Polaris, the North Star.



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



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Dwarf galaxy provides a window into the early universe

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

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



"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 ionized 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 who study stellar evolution and the life cycle of stars.



The structure of NGC 1559 includes well-defined spiral arms that contain 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>.



<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 NASA Earth Observatory features smoke from wildfires across the southeastern region of South Korea.



NASA noted that dozens of <a href="https://www.earth.com/news/experts-have-identified-the-key-driver-of-severe-wildfires-in-canada/" target="_blank" rel="noreferrer noopener">wildland fires</a> broke out as dry winds swept across the country.



“Blazes began igniting on March 21, prompting evacuations as well as the deployment of thousands of personnel and more than 100 helicopters to combat the fires.”



<h2 class="wp-block-heading" id="h-smoke-from-wildfires-in-south-korea">Smoke from wildfires in South Korea </h2>



“Smoke from some of the larger fires is visible in this image, acquired by the MODIS (Moderate Resolution Imaging Spectroradiometer) on NASA’s Aqua satellite on March 22,” said <a href="https://earthobservatory.nasa.gov/images/154083/outbreak-of-fire-across-south-korea" target="_blank" rel="noreferrer noopener">NASA</a>.



One of the plumes is streaming from a wildfire near Andong in Uiseong County, where hundreds of people were evacuated.&nbsp;



“To the south, another large smoke plume originated from rural Sancheong County,” noted NASA.



‘A large, fast-moving fire had burned over 500 hectares (2 square miles) by the evening of March 22, the Associated Press reported, and caused multiple injuries and deaths.”&nbsp;



<h2 class="wp-block-heading" id="h-impacts-of-the-fires">Impacts of the fires</h2>



The devastating wildfires in South Korea have caused significant loss of life and property. The fires have claimed at least 24 lives, including four firefighters and a helicopter pilot who crashed while assisting in the efforts. 



Approximately 27,000 residents have been forced to evacuate as the flames have burned more than 17,000 hectares of land.&nbsp;



The fires have caused extensive damage to infrastructure and cultural heritage sites. More than 200 structures, including historical structures such as a seventh century Buddhist temple, have been destroyed.



The wildfires have spread rapidly. Lee Byung-doo, a forest disaster expert at the National Institute of Forest Science, told The Guardian that the Uiseong fire spread with “unimaginable” <a href="https://www.earth.com/news/fast-wildfires-are-gaining-even-more-speed/" target="_blank" rel="noreferrer noopener">speed</a>.&nbsp;



Dry, windy conditions and record-high temperatures have made the fires difficult to contain.&nbsp;



The government has elevated the crisis alert to its highest level, deploying thousands of firefighters and over 130 helicopters to combat the blazes.



The hardest hit regions have been designated as disaster areas to expedite recovery efforts.



<h2 class="wp-block-heading" id="h-climate-change-and-wildfire-dynamics-nbsp">Climate change and wildfire dynamics&nbsp;</h2>



<a href="https://www.earth.com/news/extreme-fire-risk-has-grown-exponentially-in-a-hotter-climate/" target="_blank" rel="noreferrer noopener">Climate change</a> is significantly influencing wildfire intensity by creating conditions that make fires more frequent, larger, and more severe.&nbsp;



Rising global temperatures lead to prolonged <a href="https://www.earth.com/news/climate-change-is-now-the-driving-force-behind-droughts/" target="_blank" rel="noreferrer noopener">droughts</a>, drier vegetation, and higher evaporation rates, all of which contribute to an increased likelihood of wildfires.&nbsp;



As heat waves become more extreme and prolonged, forests and grasslands become more susceptible to ignition, whether from natural sources like lightning or human activity.



Shifting precipitation patterns also play a role in wildfire dynamics. Some regions experience less frequent but more intense rainfall, leading to rapid vegetation growth that, once dried out, becomes highly flammable fuel for fires.&nbsp;



In other areas, persistent droughts reduce soil moisture and weaken plant health, making ecosystems more vulnerable to burning.



<h2 class="wp-block-heading" id="h-rapid-and-unpredictable-fires-nbsp">Rapid and unpredictable fires&nbsp;</h2>



The warming climate is also altering wind patterns, which can spread fires more rapidly and unpredictably. Stronger winds carry embers over long distances, igniting new fires far from the original source.&nbsp;



Additionally, changes in seasonal patterns, such as earlier snowmelt and delayed autumn rains, extend the wildfire season, allowing fires to burn longer and with greater intensity.



These intensifying wildfires have cascading effects on ecosystems and human communities. Increased fire severity can lead to soil degradation, loss of biodiversity, and long-term changes in forest composition.&nbsp;



In populated areas, wildfires pose serious threats to human life, property, and air quality, with smoke from large fires contributing to respiratory health issues and worsening climate change by releasing massive amounts of carbon dioxide into the atmosphere.



<h2 class="wp-block-heading" id="h-an-escalating-cycle-nbsp">An escalating cycle&nbsp;</h2>



Ultimately, climate change and wildfires form a dangerous feedback loop. As wildfires become more intense and widespread, they release more carbon, accelerating climate change and increasing future fire risks.&nbsp;



This escalating cycle highlights the urgent need for strategies to mitigate climate change and improve wildfire management through policies that address both emissions reductions and adaptive land-use practices.



Image Credit: NASA Earth Observatory&nbsp;



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Smoke and destruction: South Korea’s wildfire crisis

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

Today's Image of the Day from NASA Earth Observatory features Ksudach, a remarkable volcanic complex located on Russia's Kamchatka Peninsula.



“The peninsula is one of the world’s most active volcanic arcs due to tectonic plate movement, with the Pacific Plate subducting under the Eurasian Plate,” noted <a href="https://earthobservatory.nasa.gov/images/153779/ksudachs-nested-calderas-and-craters" target="_blank" rel="noreferrer noopener">NASA</a>.



<h2 class="wp-block-heading" id="h-explosive-eruptions-of-ksudach">Explosive eruptions of Ksudach</h2>



Ksudach is classified as a shield <a href="https://www.earth.com/news/new-camera-helps-scientists-forecast-volcanic-eruptions/" target="_blank" rel="noreferrer noopener">volcano</a> due to the gentle slopes formed by its extensive lava flows. The combination of its shield-like structure and the prominent caldera system makes Ksudach a unique volcanic feature on the Kamchatka Peninsula.



“Several overlapping calderas and craters comprise the volcano. Calderas are large, bowl-shaped depressions created by the collapse of overlying material into an emptied subsurface magma chamber,” explained NASA.



“Craters are circular depressions created by volcanic activity, surface impacts, or explosions.”



This volcanic system has a fascinating geological history shaped by multiple explosive eruptions.&nbsp;



The most significant of these occurred around 240 AD, leaving behind a prominent caldera that now hosts scenic crater lakes, such as Lake Ksudach. 



“Lakes within the volcanic region are primarily recharged by rain and snowmelt from the winter season. This photo shows the water’s contrasting blue hues surrounded by green vegetation,” noted NASA.



“Traces of snow fill valleys within and outside the volcano’s caldera complex. These snow-covered areas highlight the drainage patterns from higher to lower elevations. Water that flows through these erosional pathways and into the caldera supports its vegetation and lakes.”



<h2 class="wp-block-heading" id="h-unique-landscape-of-ksudach-nbsp">Unique landscape of Ksudach&nbsp;</h2>



Ksudach's landscape also features pyroclastic deposits, lava flows, and hydrothermal features like fumaroles.&nbsp;



The surrounding environment - which is part of the UNESCO-listed Kamchatka Volcanoes - supports a diverse ecosystem with unique wildlife. 



Despite its remote location, Ksudach has drawn the attention of geologists, offering insights into <a href="https://www.earth.com/news/underwater-volcanic-eruptions-are-more-harmful-than-previously-believed/" target="_blank" rel="noreferrer noopener">volcanic processes</a> and the dynamics of caldera formation.



<h2 class="wp-block-heading" id="h-dynamic-nature-of-earth-s-geology-nbsp">Dynamic nature of Earth's geology&nbsp;</h2>



The most well-documented eruption of Ksudach occurred in March 1907. This eruption ranks as one of the largest in Kamchatka in the 20th century, with a Volcanic Explosivity Index (VEI) of 5.



The eruption produced a colossal ash column that soared into the stratosphere, dispersing fine particles over vast distances and contributing to global atmospheric changes.&nbsp;



The sheer force of the <a href="https://www.earth.com/news/icelands-volcanic-eruptions-may-continue-for-decades/" target="_blank" rel="noreferrer noopener">eruption</a> unleashed pyroclastic flows - fast-moving avalanches of hot gas, ash, and volcanic debris - that raced down the volcano's slopes, obliterating everything in their path.&nbsp;



These flows, capable of reaching temperatures over 1,000°C, decimated vegetation and altered the topography of the surrounding region.&nbsp;



Simultaneously, tephra deposits blanketed the landscape in layers of thick volcanic material, smothering ecosystems and creating a barren wasteland.&nbsp;



Today, Ksudach is considered an active <a href="https://www.earth.com/news/axial-seamount-large-underwater-volcano-off-us-coast-will-likely-erupt-in-2025/" target="_blank" rel="noreferrer noopener">volcano</a> but remains dormant. The region is closely monitored due to its potential for renewed <a href="https://www.earth.com/news/new-research-enhances-predictions-on-volcanic-eruptions/" target="_blank" rel="noreferrer noopener">activity</a>.



<h2 class="wp-block-heading" id="h-pacific-ring-of-fire-nbsp">Pacific Ring of Fire&nbsp;</h2>



The Kamchatka Peninsula lies along the Pacific Ring of Fire, a horseshoe-shaped zone encircling the Pacific Ocean where tectonic activity is highly concentrated.&nbsp;



This geologically dynamic area features numerous volcanoes, hot springs, geysers, and frequent seismic activity - making it a hotspot for both natural beauty and scientific study. 



Kamchatka is home to over 160 volcanoes, with about 30 considered active, including Klyuchevskaya Sopka, the highest and one of the most active in the region.



<h3 class="wp-block-heading" id="h-volcanic-activity-nbsp">Volcanic activity&nbsp;</h3>



As the Pacific Plate dives into the Earth's mantle, it melts and generates magma that feeds Kamchatka’s volcanic systems.&nbsp;



This ongoing tectonic interaction also contributes to the broader activity of the Pacific Ring of Fire, which accounts for approximately 75% of the world's active and dormant <a href="https://www.earth.com/news/supervolcano-italy-solfatara-crater-phlegraean-fields-shows-signs-of-waking-up/" target="_blank" rel="noreferrer noopener">volcanoes</a> and about 90% of its earthquakes.



<h3 class="wp-block-heading" id="h-broader-significance-nbsp">Broader significance&nbsp;</h3>



Beyond its geological significance, the Kamchatka Peninsula boasts a diverse ecosystem that is home to animals such as snow sheep, brown bears, red foxes, and unique plants that are adapted to its harsh environment. 



The coastal waters surrounding the peninsula support various fish species, including abundant salmon, as well as sea lions and killer whales.



The interplay of volcanic landscapes and pristine wilderness makes it a natural laboratory for understanding Earth's dynamic processes.



The image was captured by an astronaut aboard the International Space Station.



Image Credit: NASA Earth Observatory&nbsp;



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Ksudach: A volcano shaped by explosive forces

Today's Image of the Day from the European Space Agency features a galaxy that is located about 600 million light-years away in the constellation Gemini. The Hubble Space Telescope observed a supernova in this galaxy - which appears as a bright blue dot in the photograph.



“This picture was taken roughly two months after a supernova named SN 2022aajn was discovered in this galaxy. The supernova is visible as a blue dot at the center of the image, brightening the hazy body of the galaxy,” noted <a href="https://www.esa.int/ESA_Multimedia/Images" target="_blank" rel="noreferrer noopener">ESA</a>.



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



Supernovae are spectacular explosions marking the violent deaths of stars. These cosmic events are so luminous they can briefly outshine entire <a href="https://www.earth.com/news/galaxies-are-much-bigger-than-we-originally-believed-gas-clouds/" target="_blank" rel="noreferrer noopener">galaxies</a> and radiate more energy in a few weeks than our Sun will in its entire lifetime.&nbsp;



Supernovae explosions release heavy elements like carbon, oxygen, and iron into the interstellar medium. This stellar debris becomes the building blocks for new stars, planets, and even life itself. 



Supernovae also produce neutron stars or black holes, depending on the remaining core’s mass after the explosion.



<h2 class="wp-block-heading" id="h-types-of-supernovae-nbsp">Types of supernovae&nbsp;</h2>



There are two main types of supernovae, classified based on their causes. Type I supernovae occur when a <a href="https://www.earth.com/news/white-dwarf-stars-may-be-billions-of-years-older-than-estimated/" target="_blank" rel="noreferrer noopener">white dwarf</a> in a binary system accretes material from its companion star, eventually reaching a critical mass and triggering a runaway nuclear reaction.&nbsp;



Type II supernovae happen when a massive star, at least eight times the mass of the Sun, exhausts its nuclear fuel. Unable to support its own gravity, the core collapses, resulting in a massive explosion that ejects the outer layers into space.



<h2 class="wp-block-heading" id="h-measuring-the-distance-to-faraway-galaxies-nbsp">Measuring the distance to faraway galaxies&nbsp;</h2>



According to ESA, SN 2022aajn is a Type Ia supernova. “Supernovae of this type help astronomers measure the distance to faraway galaxies. This is possible because Type Ia supernovae are thought to be of the same intrinsic luminosity - no matter how bright they seem from Earth, they put out the same amount of light as other Type Ia supernovae.”



This means that researchers can calculate the distance to the supernova and its host galaxy by comparing the observed brightness to the expected brightness.



“This seemingly simple measurement method is complicated by cosmic dust. The farther away a supernova is, the fainter and redder it will appear - but intergalactic dust can make a supernova appear fainter and redder as well,” explained ESA.



“To understand this complication, researchers will use Hubble to survey a total of 100 Type Ia supernovae in seven wavelength bands from the ultraviolet to the near-infrared.”



By analyzing the brightness of supernovae across multiple wavelengths, researchers can distinguish between the influences of dust and distance, refining our measurements of galaxies that exist billions of light-years away.



<h2 class="wp-block-heading" id="h-how-many-galaxies-exist">How many galaxies exist?</h2>



The number of galaxies in the universe is estimated to be around two trillion, based on observations from Hubble and more recent data from the James Webb Space Telescope. 



This estimate is derived from deep-field surveys that reveal countless galaxies, each containing billions to trillions of <a href="https://www.earth.com/news/interstellar-tunnel-found-that-connects-our-solar-system-to-other-stars/" target="_blank" rel="noreferrer noopener">stars</a>.&nbsp;



However, because our observations are limited by current technology and the vastness of the cosmos, the actual number could be even higher.&nbsp;



Many <a href="https://www.earth.com/news/ancient-galaxies-formed-from-the-earliest-elements-in-the-universe/" target="_blank" rel="noreferrer noopener">galaxies</a> remain unseen due to their extreme distances, faintness, or obstruction by cosmic dust.



<h2 class="wp-block-heading" id="h-the-constellation-gemini-nbsp">The constellation Gemini&nbsp;</h2>



Gemini is one of the 12 zodiac constellations and is best known for representing the mythological twins Castor and Pollux. It is located in the northern celestial hemisphere and is most visible during winter in the Northern Hemisphere.&nbsp;



The constellation is bordered by Taurus to the west, Cancer to the east, and Orion to the south.



The two brightest stars in Gemini - Castor and Pollux - represent the heads of the twins and are easy to spot. Pollux, the brighter of the two, is an orange giant star about 34 light-years from Earth, while Castor is a more complex system made up of six stars. 



The constellation also contains several notable deep-sky objects, including the open cluster Messier 35, which is a beautiful collection of young stars located near Gemini’s western border.



Image Credit: ESA&nbsp;



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Hubble spots a supernova in the constellation Gemini 

Today's Image of the Day from NASA Earth Observatory features a satellite view of retreating glaciers in Alaska, where meltwater is rapidly expanding glacial lakes. 



“In parts of Alaska, water is replacing ice. As glaciers thin and <a href="https://www.earth.com/news/satellite-images-reveal-hidden-retreat-of-arctic-glaciers/" target="_blank" rel="noreferrer noopener">retreat</a>, meltwater collects at their fronts, forming proglacial lakes. According to an analysis by Mauri Pelto, a glaciologist at Nichols College, three such lakes in the southeastern part of the state have grown rapidly in recent decades,” said <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA</a>.



<h2 class="wp-block-heading" id="h-retreating-glaciers-in-alaska">Retreating glaciers in Alaska</h2>



“A trio of glaciers - Yakutat, Alsek, and Grand Plateau - descend from inland mountains and flow onto the coastal plain southeast of Yakutat borough, ending at Harlequin Lake, Alsek Lake, and Grand Plateau Lake,” noted NASA.&nbsp;



The retreat of the glaciers, as well as the growth of the lakes, are visible in the image. When compared to an <a href="https://eoimages.gsfc.nasa.gov/images/imagerecords/153000/153638/fastestlake_tm5_19840705_lrg.jpg" target="_blank" rel="noreferrer noopener">image</a> captured by Landsat 5 in the summer of 1984, the changes are even more evident.



NASA elaborated on the extent of the glacier retreat from 1984 to 2024. “During this period, Yakutat Glacier’s main arm retreated 4.3 miles, while Alsek Glacier’s northern and southern arms retreated 3.3 miles and 3.4 miles, respectively. Grand Plateau Glacier’s northern arm lost the most, retreating 4.8 miles.”



<h2 class="wp-block-heading" id="h-glacial-lakes-doubled-in-size-nbsp">Glacial lakes doubled in size&nbsp;</h2>



“Collectively, the three lakes more than doubled in size over 40 years. In 1984, they covered about 50 square miles. By 2024, they spanned 90 square miles. That’s an area larger than Seneca Lake (67 square miles) - one of the Finger Lakes in New York, which also have a glacial origin,” said NASA.



Pelto noted that the lakes forming in this region are immense - starting at the mountains and spreading toward the coast - making this a new lake district that is unique in our nation.



“Millions of other lakes, named and unnamed, dot the state. But this system has grown fast, so much so that Pelto thinks it might represent the fastest lake growth in the United States this century,” said NASA.



<h2 class="wp-block-heading" id="h-understanding-glacier-retreat-nbsp">Understanding glacier retreat&nbsp;</h2>



Glacier retreat is a significant phenomenon driven primarily by global warming the results from rising greenhouse gas <a href="https://www.earth.com/news/global-carbon-dioxide-emissions-hit-a-record-high-in-2023/" target="_blank" rel="noreferrer noopener">emissions</a>.&nbsp;



As temperatures rise, glaciers lose more ice during the summer melt than they can regain in winter snowfall, causing them to shrink over time. This process has profound implications for ecosystems, water resources, and global sea levels.



<h3 class="wp-block-heading" id="h-glacial-lakes">Glacial lakes</h3>



When glaciers retreat, they often leave behind depressions in the landscape that can fill with meltwater, forming glacial lakes. These lakes are typically bounded by natural dams made of rock, ice, or moraine - accumulations of debris left behind by the glacier's movement.&nbsp;



Over the past century, the number and size of glacial lakes worldwide have increased significantly due to the accelerating pace of <a href="https://www.earth.com/news/tropical-glaciers-offer-a-glimpse-of-our-harsh-climate-reality/" target="_blank" rel="noreferrer noopener">glacier</a> retreat. This trend is especially evident in high-altitude regions like the Himalayas, the Andes, and the Alps, as well as in polar areas such as Alaska and Greenland.



<h3 class="wp-block-heading" id="h-positive-and-negative-impacts-nbsp">Positive and negative impacts&nbsp;</h3>



Glacial lakes can have both positive and negative impacts. They provide critical water sources for downstream communities, support biodiversity, and sometimes offer opportunities for hydropower development or tourism.&nbsp;



However, they also pose serious risks. The dams holding back these lakes can fail suddenly, causing glacial lake outburst floods (GLOFs). These catastrophic events can devastate downstream areas, destroying infrastructure, agricultural lands, and habitats while endangering human lives.



<h3 class="wp-block-heading" id="h-monitoring-changes">Monitoring changes</h3>



Understanding glacier retreat and glacial lake formation requires a multidisciplinary approach, combining climate science, hydrology, and geology.&nbsp;



Monitoring these changes is essential to mitigate associated risks and adapt to the evolving landscape shaped by a <a href="https://search.app?link=https%3A%2F%2Fwww.earth.com%2Fnews%2Fperu-has-lost-over-half-of-its-glaciers-in-six-decades%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">warming planet</a>.



<h2 class="wp-block-heading" id="h-glacier-retreat-worldwide">Glacier retreat worldwide</h2>



Studies and satellite observations show that most glaciers in almost all regions of the world are shrinking.&nbsp;



Melting glaciers contribute significantly to global <a href="https://www.earth.com/news/emergency-meeting-reveals-the-alarming-extent-of-antarcticas-ice-loss/" target="_blank" rel="noreferrer noopener">sea level rise</a>, which threatens coastal communities and ecosystems.



The retreat of glaciers is considered one of the clearest indicators of climate change.&nbsp;Some glaciers are retreating at unprecedented rates, indicating accelerating climate impacts.



The image was captured on August 4, 2024 by the Landsat 8 satellite.



Image Credit: NASA Earth Observatory



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Retreating glaciers and expanding meltwater lakes in Alaska

Bee hives in the desert are always underground or in rock crevices. This large hive took residence in an old ant bear hole underground. Photo Credit: Whensilencefindsme

Desert Bee Hive

The Levant region of the Middle East has long been recognized as a mixing pot of early humans and Neanderthals, some local and some on their way to and from other geographical regions. 



The many skeletal remains that have been found are characterized by high morphological diversity, but there is a consistency in the indicators of social and cultural behaviors.



Sites in the Levant give evidence of intentional burial of the dead, the interment of grave goods and the use of ochre at burial sites. 



This evidence of social and cultural behavior predates all other such evidence in the global record by tens of thousands of years.



In a recent study, researchers have analyzed unprecedented finds from Tinshemet Cave in Israel, in order to understand the relationship between Neanderthals and Homo sapiens during the mid-Middle Paleolithic. 



Remains of both of these hominin species are present at the site, but they appear to share common habits, technology and burial rites.



<h2 class="wp-block-heading" id="h-neanderthals-humans-and-tinshemet-cave">Neanderthals, humans, and Tinshemet Cave</h2>



The site has proved to be an&nbsp;archaeological&nbsp;and&nbsp;anthropological&nbsp;treasure&nbsp;trove, with its skeletons - some of which are almost complete - burial sites and artifacts associated with these burials. 



These are the first new Middle-Paleolithic (MP) human burials to be investigated in 50 years.



The new evidence from Tinshemet Cave indicates that these <a href="https://www.earth.com/news/when-did-early-humans-first-start-wearing-clothes-and-why-parasites-lice/" target="_blank" rel="noreferrer noopener">early humans</a> were not just neighbors but were actively sharing information, and influencing each other's survival techniques, toolmaking, and cultures. 



When the finds were compared with evidence from other Levant sites, they showed similar tools, the same placement of skeletons within burial sites, artifacts that were included for use in the afterlife, and the presence of ochre fragments throughout the deposits.



This indicates that, although different types of hominins were present, they all seemed to share common cultural and social practices. 



Clearly, the relationship between early humans and Neanderthals was more complex than originally thought.



<h2 class="wp-block-heading" id="h-humans-and-neanderthals-shared-culture">Humans and Neanderthals shared culture</h2>



Excavation of the Tinshemet Cave deposits has been ongoing since 2017. It is directed by Prof. Yossi Zaidner of the <a href="https://en.huji.ac.il/" target="_blank" rel="noreferrer noopener">Hebrew University of Jerusalem</a>, Prof. Israel Hershkovitz of <a href="https://english.tau.ac.il/" target="_blank" rel="noreferrer noopener">Tel Aviv University</a>, and Dr. Marion Prévost of the Hebrew University of Jerusalem.



The primary objective of the researchers has been to unravel the nature of the relationship between Homo sapiens and Neanderthals during the mid-<a href="https://www.earth.com/news/human-evolution-overlapping/" target="_blank" rel="noreferrer noopener">Middle Paleolithic</a> period in this region. 



Was there a rivalry over resources between the two groups, or were they peaceful neighbors or collaborators?



The researchers integrated data from four essential fields - stone tool production, hunting strategies, symbolic behavior, and social complexity - for their study.



This integrated approach led to the inference that different human groups, including Neanderthals, <a href="https://www.earth.com/news/neanderthal-evolution-was-more-complex-than-previously-thought/" target="_blank" rel="noreferrer noopener">pre-Neanderthals</a>, and Homo sapiens, all of which inhabited the Levant at various times, engaged in significant interactions.



These encounters enabled the exchange of knowledge and skills, which in turn led to the mixing of cultures among these populations.



<h2 class="wp-block-heading" id="h-burial-rituals-shared">Burial rituals shared</h2>



The discovery of a cluster of human burials at the Tinshemet Cave also raises fascinating questions about the role this site played in MP society. 



Could this cave have been a dedicated burial ground or even a cemetery? 



The placement of artifacts such as <a href="https://www.earth.com/news/400000-year-old-stone-tools-show-technological-adaptations-of-prehistoric-humans/" target="_blank" rel="noreferrer noopener">stone tools</a>, animal bones, and ochre chunks within the burial pits suggests early beliefs in the afterlife, implying the presence of shared societal rituals and strong communal bonds.



<h2 class="wp-block-heading" id="h-why-does-any-of-this-matter">Why does any of this matter?</h2>



The discoveries at Tinshemet Cave offer a glimpse into a dynamic period of prehistoric human interaction, with evidence suggesting that Neanderthals and early humans not only coexisted but also influenced each other’s ways of life.



Professor Zaidner describes Israel as a "melting pot" where different human groups met, interacted, and evolved together. 



“Our data show that human connections and population interactions have been fundamental in driving cultural and technological innovations throughout history,” he explained.



Dr. Prévost highlighted the unique geographic position of the region at the crossroads of human dispersals.



“During the mid-MP, climatic improvements increased the region’s carrying capacity, leading to demographic expansion and intensified contact between different Homo taxa,” he said.



<h2 class="wp-block-heading" id="h-humans-and-neanderthals-socially-complex">Humans and Neanderthals - socially complex</h2>



This demographic shift likely facilitated social exchanges that contributed to the shared technological and cultural advancements observed in the <a href="https://www.earth.com/news/115000-year-old-human-footprints-found-alathar-lake-arabian-peninsula/" target="_blank" rel="noreferrer noopener">archaeological record</a>.



Prof. Hershkovitz commented that the interconnectedness of lifestyles among various human groups in the Levant suggests deep relationships and shared adaptation strategies. 



“These findings paint a picture of dynamic interactions shaped by both cooperation and competition.” 



The discoveries at Tinshemet Cave reinforce the notion that prehistoric human groups were not isolated entities but rather engaged in continuous exchanges that shaped their learning, survival, culture, and technological progress.



<h2 class="wp-block-heading" id="h-still-much-more-to-learn">Still much more to learn</h2>



The findings at Tinshemet Cave offer a fascinating glimpse into the social organization, symbolic practices, and everyday lives of early human populations. 



By excavating evidence of common burial practices, technological transfer, and potential cultural mixing between Neanderthals and Homo sapiens, scientists are rewriting the history of prehistoric coexistence.



As digs proceed, future discoveries might reveal further burial grounds, artifacts, or symbolic inscriptions that shed more light on the dynamics of interspecies interactions in this region.



The full study was published in the journal <a href="https://www.nature.com/articles/s41562-025-02110-y" target="_blank" rel="noreferrer noopener">Nature Human Behaviour</a>.



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Unexpected Neanderthal discovery permanently rewrites human history

The Levant region of the Middle East has long been...

Space journeys that stretch far beyond home are on the horizon. Crews heading for Mars will face conditions quite different from those on Earth, and researchers have been working to figure out what might happen to the human body during these extended voyages. 



Kidneys have been a big question mark. Recent work reveals that these important organs could face more trouble than previously assumed, including a higher risk of stones and lasting damage.



Several studies have hinted at health concerns for astronauts ever since humans first ventured outside Earth’s protective zone, but the new findings shed light on why such problems arise in the kidneys. 



Dr. Keith Siew from the <a href="https://www.londontubularcentre.org/" target="_blank" rel="noreferrer noopener">London Tubular Centre</a>, based at the UCL Department of Renal Medicine, and his colleagues have pieced together a detailed picture of what happens when living beings - human and otherwise - experience space-like conditions for weeks to years.



<h2 class="wp-block-heading" id="h-space-missions-and-human-kidneys">Space missions and human kidneys</h2>



The latest study was conducted under a UCL-led initiative involving over 40 institutions on five continents.



The team considered data from 20 different research cohorts and samples linked to over 40 Low Earth orbit missions to the <a href="https://www.earth.com/news/nasa-says-the-international-space-station-is-too-clean-add-microbes/" target="_blank" rel="noreferrer noopener">International Space Station</a>, plus 11 simulations with mice and rats. 



The work is described as the largest analysis of kidney health in spaceflight so far and includes the first health dataset for commercial astronauts. 



It also involved seven simulations in which mice were exposed to radiation that mimicked up to 2.5 years of cosmic travel beyond <a href="https://www.earth.com/earthpedia-articles/earths-magnetic-field-origin-structure-and-impact-on-humanity/" target="_blank" rel="noreferrer noopener">Earth’s magnetic field</a>. 



Findings revealed that the structure and function of the kidneys are altered by spaceflight, with galactic radiation causing permanent damage that would jeopardize any long-distance mission.



<h2 class="wp-block-heading" id="h-kidneys-and-deep-space-radiation">Kidneys and deep space radiation</h2>



Astronauts in Low Earth orbit still benefit from partial shielding by our planet’s magnetic field. 



Only 24 people - the ones who went to the moon - have been exposed to the full brunt of Galactic Cosmic Radiation for short trips of about 6-12 days. 



Nobody has ventured on a years-long mission beyond the Earth’s magnetic boundary, so it was unclear how organs might hold up under <a href="https://www.earth.com/news/voyager-spacecraft-fighting-survival-cosmic-threats-outside-our-solar-system/" target="_blank" rel="noreferrer noopener">more extreme conditions</a>.



As part of the new study, researchers found that certain kidney tubules, which control delicate balances of salts and calcium, shrink after just a month in <a href="https://www.earth.com/news/microgravity-causes-big-problems-with-human-gene-expression/" target="_blank" rel="noreferrer noopener">microgravity</a>. 



The kidneys also process salts in a way that increases the likelihood of kidney stone formation. 



This new insight shifts the focus away from an older assumption that stones in space result mainly from bone loss causing elevated calcium in urine.



<h2 class="wp-block-heading" id="h-longer-distance-more-radiation">Longer distance, more radiation</h2>



The research highlighted that cosmic radiation cannot be fully blocked by typical shielding. When mice were given doses of simulated <a href="https://www.swpc.noaa.gov/phenomena/galactic-cosmic-rays" target="_blank" rel="noreferrer noopener">Galactic Cosmic Radiation</a> equal to a mission length of up to 2.5 years, the animals showed irreversible kidney damage. 



Some of the key observations point to changes in how the kidneys manage vital minerals, which impacts long-term health during space travel.



“We know what has happened to astronauts on the relatively short space missions conducted so far, in terms of an increase in health issues such as kidney stones,” explained Dr. Siew. 



“What we don’t know is why these issues occur, nor what is going to happen to astronauts on longer flights such as the proposed <a href="https://www.earth.com/news/mars-curiosity-rover-finds-sulfur-crystals-martian-rock-hints-at-possible-life/" target="_blank" rel="noreferrer noopener">mission to Mars</a>.”



If scientists don’t develop new ways to protect the kidneys, any astronaut that makes it to <a href="https://www.earth.com/news/largest-organic-molecules-ever-found-on-mars-confirm-life-forming-chemistry-is-possible/" target="_blank" rel="noreferrer noopener">Mars</a> will likely need dialysis on the way home or upon arrival.



"We know that the kidneys are late to show signs of radiation damage; by the time this becomes apparent it’s probably too late to prevent failure, which would be catastrophic for the mission’s chances of success," Dr. Siew concluded.



<h2 class="wp-block-heading" id="h-human-kidneys-and-future-space-travel">Human kidneys and future space travel</h2>



Space agencies have been aware since the 1970s that journeys outside our planet’s natural defenses lead to health concerns involving bones, eyes, and the <a href="https://www.earth.com/news/a-century-of-progress-in-the-fight-against-cardiovascular-disease/" target="_blank" rel="noreferrer noopener">cardiovascular system</a>. 



This new work puts fresh focus on the kidneys. It also highlights the importance of managing both microgravity and radiation, especially with more ambitious missions on the table.



“Our study highlights the fact that if you’re planning a space mission, kidneys really matter. You can’t protect them from galactic radiation using shielding," noted Professor Stephen B. Walsh from the London Tubular Centre, UCL Department of Renal Medicine.



"But as we learn more about renal biology it may be possible to develop technological or pharmaceutical measures to facilitate <a href="https://www.earth.com/news/space-travel-has-unexpected-effects-on-gut-health/" target="_blank" rel="noreferrer noopener">extended space travel</a>."



Any drugs developed for astronauts may also be beneficial here on Earth. For instance, by enabling cancer patients’ kidneys to tolerate higher doses of radiotherapy, which is currently an impediment to that form of treatment.



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



Though this work only outlines organ changes up to two and a half years, it stands as the most comprehensive data currently available for that timescale. 



Researchers say that pinpointing these risks is a vital first step before reliable solutions can be introduced. 



The study’s international collaboration suggests momentum is building to safeguard astronauts’ kidneys, and future innovations could reach beyond space missions to help patients on Earth.



Experts note that learning how to handle the combined effects of microgravity and cosmic radiation will be key to making ambitious missions safer. 



With evidence pointing to serious kidney challenges, careful planning will be needed to keep crews healthy on journeys that last far longer than any undertaken before.



The full study was published in the journal <a href="https://www.nature.com/articles/s41467-024-49212-1" target="_blank" rel="noreferrer noopener">Nature Communications</a>.



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Astronauts can survive a trip to Mars, but one crucial organ will likely fail

Space journeys that stretch far beyond home are on the...

Young,Woman,Drinking,Water,Outdoors,,Promoting,Healthy,Hydration,And,An

Plastic containers and packaging are everywhere, as many people rely on them for food storage, convenience, and hydration. Plastics have improved modern life in countless ways, but the ultimate price of this convenience is only now coming clearly into focus.



We have reached the point as a society where researchers have begun looking beyond the environmental hazards of plastic pollution to uncover hidden connections between plastic exposure and human well-being. 



Questions are emerging about how microplastics might be <a href="https://www.earth.com/news/your-chewing-gum-may-be-full-of-microplastics/" target="_blank" rel="noreferrer noopener">affecting our bodies</a> and whether this is something we should address.



Some everyday items, such as water bottles, may contribute far more than trash. They could be releasing tiny plastic particles that slip into our bodies. 



Early studies suggest that plastic particles are influencing human <a href="https://www.earth.com/news/study-reveals-over-2000-genetic-markers-that-affect-blood-pressure/" target="_blank" rel="noreferrer noopener">blood pressure</a>, a condition linked to serious cardiovascular problems. 



According to Dr. Johanna Fischer from the Department of Medicine at <a href="https://www.dp-uni.ac.at/en" target="_blank" rel="noreferrer noopener">Danube Private University</a> in Austria, a few recent findings have sparked new debates about what happens when microplastics flow through our bloodstream.



<h2 class="wp-block-heading" id="h-tiny-pieces-of-plastic-wreaking-havoc">Tiny pieces of plastic wreaking havoc</h2>



Microplastics measure less than 5 mm, arising from the breakdown of larger plastics or from everyday sources like car tires and synthetic clothing. 



They have been detected in <a href="https://www.earth.com/news/microplastics-pose-a-greater-threat-to-some-ocean-animals/" target="_blank" rel="noreferrer noopener">food, water, and the air</a>. Scientists have identified them in the placenta, in certain organs, and even in the bloodstream. 



Their presence has raised concerns because they might trigger inflammation or hormonal imbalances. By entering daily routines unnoticed, these microscopic bits could pose health hazards that are still under investigation.



Recent work has pointed to an unexpected culprit for high blood pressure. Their investigations indicate that common water bottles can release particles into the liquid we drink. 



According to preliminary insights, microplastics can migrate into our system, with potential effects on <a href="https://www.earth.com/news/can-smell-control-your-blood-pressure-new-research-says-yes/" target="_blank" rel="noreferrer noopener">blood pressure measurements</a>. 



Investigators also discovered these minute fragments in glass containers, which complicates efforts to avoid them altogether. 



This points to a wider issue that stretches beyond visible waste and calls for innovative approaches to monitoring exposure.



<h2 class="wp-block-heading" id="h-plastics-linked-to-blood-pressure">Plastics linked to blood pressure</h2>



Eight healthy adults took part in a project aimed at exploring any links between plastics and blood pressure. 



They were asked to rely on tap water instead of bottled drinks for about a month. <a href="https://www.earth.com/news/black-gold-the-vitamin-packed-fruit-that-regulates-blood-sugar-and-blood-pressure/" target="_blank" rel="noreferrer noopener">Blood pressure</a> readings were collected at the outset, after two weeks, and at the end of four weeks. 



The findings indicated that women showed a noticeable dip in blood pressure levels, particularly in diastolic readings, while men did not exhibit the same changes.



One explanation might be that only three men participated. That small number makes it difficult to form broad conclusions. 



Still, the overall data hint that cutting back on plastics could influence cardiovascular health by reducing the number of <a href="https://www.earth.com/news/microplastics-are-widespread-in-the-seafood-we-eat/" target="_blank" rel="noreferrer noopener">plastic particles</a> present in the bloodstream. 



The research group emphasizes that larger trials are needed. They aim to measure the actual concentration of microplastics in the blood, providing a clearer picture of how plastic exposure might relate to changes in blood pressure.



<h2 class="wp-block-heading" id="h-blood-pressure-and-plastics-the-results">Blood pressure and plastics - the results</h2>



“We concluded, after extensive research, that beverages packaged in plastic bottles should be avoided,” the research team warned. 



The changes observed in blood pressure suggest that reducing the <a href="https://www.earth.com/news/microplastics-in-the-brain-alarming-new-details-revealed/" target="_blank" rel="noreferrer noopener">intake of plastic particles</a> could lower cardiovascular risk, emphasizing how these findings may fit into the bigger picture. 



For these scientists, a lower exposure to plastics seems to correlate with improvements in some blood pressure markers.



By stating that “plastic particles <a href="https://www.earth.com/news/microplastics-found-in-every-semen-sample-tested/" target="_blank" rel="noreferrer noopener">present in the bloodstream</a> could contribute to increased blood pressure,” the team highlighted a potential link between microplastics and cardiovascular concerns. 



Although their study involved only a small group, they view the results as a motivation to investigate these interactions further. 



While the precise pathways remain unclear, the prospect that tiny plastic fragments might affect blood pressure and overall cardiovascular health should encourage us all to rethink these common habits.



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



Because hypertension is a leading cause of heart complications, any factor that might raise blood pressure deserves scrutiny. 



Humans already face multiple risks for cardiovascular disease, so identifying one that might be avoidable is compelling. 



Limiting bottled beverages or opting for tap water in reusable non-plastic containers will definitely help reduce exposure, though additional verification is needed to confirm the long-term impacts.



Reviewing many different studies, it's very clear that microplastics have infiltrated every nook and cranny of our bodies, natural environments, and <a href="https://www.earth.com/news/sounding-the-alarm-microplastics-are-disrupting-photosynthesis-around-the-world/" target="_blank" rel="noreferrer noopener">global ecosystems at large</a>. 



On top of high blood pressure and other cardiovascular health issues that arise from the consumption of microplastics, scientists and physicians are concerned about inflammation, endocrine problems, and oxidative stress, all of which can harm overall health. 



Though the convenience of disposable products is tempting, making a personal choice of removing single-use plastics from our everyday lives will undoubtedly yield benefits - both for our health and the global environment. 



The full study was published in the journal <a href="https://www.mdpi.com/2673-8929/3/3/26" target="_blank" rel="noreferrer noopener">Microplastics</a>.



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Drinking from plastic bottles directly linked to high blood pressure and heart problems

Plastic containers and packaging are everywhere, as many people rely...

It’s not much of a stretch to say that Earth’s inner structure, especially the innermost spherical core, has stupefied scientists for generations. It sits over 3,000 miles below the surface, smaller than the Moon yet massive enough to play a big part in Earth’s magnetic field. 



A recent study in Nature Geoscience points to changes that started around 2010, suggesting Earth's inner core’s spin was slowing. 



In effect, it was found to be to be reversing and backtracking relative to the planet’s surface. This discovery has sparked fresh conversations about how the planet’s interior behaves over time.



Geophysicists have used <a href="https://www.earth.com/news/can-we-detect-major-earthquakes-months-in-advance/" target="_blank" rel="noreferrer noopener">earthquake signals</a> from nearly every continent to probe the inner core, which is surrounded by a swirling layer of liquid metal. Findings point to structural shifts in the iron sphere that raise new questions. 



After two decades of debate, investigators feel more confident linking these signals to an actual slowdown rather than an imagined event. 



<a href="https://dornsife.usc.edu/profile/john-vidale/" target="_blank" rel="noreferrer noopener">John Vidale</a>, Dean’s Professor of Earth Sciences at the <a href="https://dornsife.usc.edu/" target="_blank" rel="noreferrer noopener">USC Dornsife College</a> of Letters, Arts and Sciences, worked on the project with Wei Wang of the <a href="https://english.cas.cn/" target="_blank" rel="noreferrer noopener">Chinese Academy of Sciences</a>.



<h2 class="wp-block-heading" id="h-innermost-layers-of-earth-s-interior">Innermost layers of Earth's interior</h2>



<a href="https://www.earth.com/news/continent-sized-islands-llsvp-found-inside-earth-are-100-times-taller-than-mount-everest/" target="_blank" rel="noreferrer noopener">Earth’s interior</a> can be divided into several layers: the crust, <a href="https://www.earth.com/news/sunken-worlds-discovered-under-the-pacific-ocean-in-earths-mantle/" target="_blank" rel="noreferrer noopener">the mantle</a>, the liquid outer core, and the solid inner core at the center. Many scientists have studied how the inner core moves relative to the mantle and crust. 



Some found evidence that the core once rotated faster than the rest of Earth. Others noticed it might be easing up. 



The latest data points to “unambiguous evidence” of a slower pace starting around 2010, landing it at a speed slightly below that of Earth’s surface.



“When I first saw the seismograms that hinted at this change, I was stumped. But when we found two dozen more observations signaling the same pattern, the result was inescapable," Vidale explained. 



"The inner core had slowed down for the first time in many decades. Other scientists have recently argued for similar and different models, but our latest study provides the most convincing resolution.”



<h2 class="wp-block-heading" id="h-records-from-earthquakes-and-nukes">Records from earthquakes and nukes</h2>



Researchers rely on waves generated by earthquakes to examine the farthest corners of our planet. These waves pass through the inner core, reflecting minute details about its movement and shape. 



For their analysis, the team gathered readings from 121 repeating earthquakes originating near the South Sandwich Islands between 1991 and 2023. 



They also tapped into data from Soviet nuclear tests conducted between 1971 and 1974, as well as repeated French and American nuclear tests.



Vidale attributes the pace shift to the “churning of the liquid iron outer core that surrounds it, which generates <a href="https://www.earth.com/earthpedia-articles/earths-magnetic-field-origin-structure-and-impact-on-humanity/" target="_blank" rel="noreferrer noopener">Earth’s magnetic field</a>, as well as gravitational tugs from the dense regions of the overlying rocky mantle.” 



Investigators think these forces may slightly affect day length. “It’s very hard to notice, on the order of a thousandth of a second, almost lost in the noise of the churning oceans and atmosphere.”



<h2 class="wp-block-heading" id="h-earth-s-inner-core-is-backtracking">Earth's inner core is "backtracking"</h2>



Some prior research indicated that the inner core might be reversing itself. The new results add weight to that possibility by suggesting the core’s rotation has slowed and even begun shifting direction compared to Earth’s outer layers. 



Vidale “didn’t set out to define the physical nature of the inner core.” Yet the project unexpectedly uncovered more than just a slowdown in rotation. 



“What we ended up discovering is evidence that the near surface of Earth’s inner core undergoes structural change,” Vidale said.



Shifting layers deep underground might explain certain fluctuations in day length, but these effects are so slight that most people never detect them. 



The team believes dynamic interactions between the liquid outer core and <a href="https://www.earth.com/news/ringwoodite-mineral-confirms-vast-ocean-exists-400-miles-under-earths-crust/" target="_blank" rel="noreferrer noopener">dense mantle zones</a> drive these shifts, making the inner core’s movement appear to switch course from time to time.



<h2 class="wp-block-heading" id="h-surprising-clues-from-seismograms">Surprising clues from seismograms</h2>



“But as I was analyzing multiple decades’ worth of seismograms, one dataset of seismic waves curiously stood out from the rest,” Vidale said. 



He and his colleagues analyzed waveforms picked up by monitoring stations in places like Fairbanks, Alaska, and Yellowknife, Canada. 



“At first the dataset confounded me,” Vidale said. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/03/earth-inner-core_less-solid_USC_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2025/03/earth-inner-core_less-solid_USC_1s.webp" alt="Diagram showing the Earth's inner core, once thought to be solid. Credit: USC" class="wp-image-1963609"/></a><figcaption class="wp-element-caption">Diagram showing the Earth's inner core, once thought to be solid. Click to enlarge. Credit: USC</figcaption></figure>



Modern techniques have since sharpened the picture, indicating that the inner core’s boundary may go through slow changes in shape caused by viscous deformation.



“What we’re observing in this study for the first time is likely the outer core disturbing the inner core,” Vidale said. 



Rather than acting like a rigid ball locked in place, the inner core seems to adapt over intervals that current seismic devices are finally able to capture. 



Scientists suspect this iron center may shift in ways that influence the planet’s magnetic field, given how much of that field is generated by the <a href="https://www.earth.com/news/how-earths-mantle-shapes-surface-topography/" target="_blank" rel="noreferrer noopener">liquid outer region</a>.



<h2 class="wp-block-heading" id="h-why-does-earth-s-inner-core-matter">Why does Earth's inner core matter?</h2>



Experts at USC aim to track the core’s patterns more precisely in the years ahead. They plan to zero in on subtle signals that show how the inner core’s shape evolves. 



They hope this effort might offer a clearer picture of the underlying forces behind any reversing motion, including interactions that appear to adjust the core’s boundaries.



While Earth's inner core is often portrayed as static and solid, these fresh observations add nuance. Repeating earthquakes provide a valuable peek at what’s happening in an environment most people can only imagine. 



The research team believes that following waveforms from future quakes could unlock details about how Earth’s center changes over time. 



Vidale said the focus is on mapping these movements in ways that help scientists see what triggers the shifts in speed and form.



The new waveforms expand the broader conversation on Earth’s mechanics. Certain aspects, like magnetic fluctuations and temperature gradients, may link back to the inner core’s pace. 



Though the planet’s center remains out of reach, these findings reveal a place that is much more active than once believed.



The full study from 2024 was published in the journal <a href="https://www.nature.com/articles/s41586-024-07536-4" target="_blank" rel="noreferrer noopener">Nature</a>.



The full study from February 2025 was published in the journal <a href="https://www.nature.com/articles/s41561-025-01642-2" target="_blank" rel="noreferrer noopener">Nature Geoscience</a>.



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Proof: Earth's inner core is rapidly changing and now 'rotating backwards'

It’s not much of a stretch to say that Earth’s...

Healthy eating has always been a hotly debated topic, but fresh findings now connect balanced meals in midlife to a stronger chance of enjoying life in one’s later years.



Experts have long studied how food choices can offset chronic issues, and they keep exploring ways to maximize overall well-being without adopting overly restrictive <a href="https://www.earth.com/news/global-diet-shifts-the-hidden-costs-of-what-we-eat/" target="_blank" rel="noreferrer noopener">diets</a>.



One recent <a href="https://www.nature.com/articles/s41591-025-03570-5" target="_blank" rel="noreferrer noopener">investigation</a> followed more than 105,000 Americans in their journey from midlife through senior status, over three decades. The study closely examined the impact of daily eating habits on long-term health.



One of the lead investigators is Professor Anne-Julie Tessier from the <a href="https://www.umontreal.ca/en/" target="_blank" rel="noreferrer noopener">University of Montreal</a>. She wanted to see whether smart nutrition could boost the odds of turning 70 with steady mental, physical, and cognitive abilities.



<h2 class="wp-block-heading" id="h-midlife-eating-patterns">Midlife eating patterns</h2>



“Studies have previously investigated dietary patterns in the context of specific diseases or how long people live,” said Frank Hu, a professor of nutrition and epidemiology at Harvard Chan School.



“Ours takes a multifaceted view, asking, how does <a href="https://www.earth.com/news/what-you-eat-can-literally-change-the-world/" target="_blank" rel="noreferrer noopener">diet</a> impact people’s ability to live independently and enjoy a good quality of life as they age?"



Participants gravitating toward vegetables, fruits, legumes, and whole grains tended to avoid critical illnesses like diabetes or heart disease more often. 



This concept of healthy aging, which includes freedom from serious chronic issues and solid mental and physical function, is recognized by the <a href="https://apps.who.int/iris/handle/10665/186463" target="_blank" rel="noreferrer noopener">World Health Organization</a> for emphasizing longevity with vitality.



<h2 class="wp-block-heading" id="h-healthy-diets-can-be-personalized">Healthy diets can be personalized </h2>



The researchers examined a range of eating strategies, each emphasizing nutritious foods and lower intake of sweets, refined grains, and processed meats.



These patterns often highlighted plant-based staples, modest amounts of lean animal protein, and reduced sodium - all designed to align with established guidelines for better health.



“Our findings also show that there is no one-size-fits-all diet. Healthy <a href="https://www.earth.com/news/small-changes-in-diet-can-greatly-reduce-your-carbon-footprint/" target="_blank" rel="noreferrer noopener">diets</a> can be adapted to fit individual needs and preferences,” said Professor Tessier.



<h2 class="wp-block-heading" id="h-health-impact-of-processed-foods">Health impact of processed foods</h2>



“Since staying active and independent is a priority for both individuals and public health, research on healthy aging is essential,” said study co-author Marta Guasch-Ferré, who is an associate professor at the <a href="https://www.ku.dk/en" target="_blank" rel="noreferrer noopener">University of Copenhagen</a>.



The experts also observed that certain participants consumed more packaged snacks, sugary beverages, and ready-to-eat <a href="https://www.earth.com/news/ditch-the-diet-trends-for-a-healthier-relationship-with-food/" target="_blank" rel="noreferrer noopener">meals</a>, which frequently contain excessive sodium, unhealthy fats, and artificial additives.&nbsp;



High intake of these convenience items was connected to lower rates of physical mobility, weaker mood regulation, and more prevalent health complications as people aged. 



Those who opted for fresher, less refined foods generally reported easier movement, stable cognitive function, and fewer day-to-day difficulties throughout their 70s.



<h2 class="wp-block-heading" id="h-midlife-eating-affects-health-after-70">Midlife eating affects health after 70</h2>



Remaining energetic beyond 70 involves more than dodging conditions like heart attacks or cancer; it also means sustaining the ability to get around and maintain positive mental health. 



A diet rich in fiber, vitamins, and protective minerals seems to support clearer thinking, stronger muscles, and steadier emotions.



According to the research team, midlife is a window when many people can still modify their routines, making it a perfect stage to bolster long-term well-being. 



By prioritizing fruits, vegetables, whole grains, and other nutrient-dense choices, adults might improve their odds of staying vibrant well into their eighth decade.



<h2 class="wp-block-heading" id="h-limitations-of-the-study">Limitations of the study</h2>



Most of the volunteers were employed in healthcare, which may mean they already had above-average awareness about nutrition, self-care, and disease prevention. 



This could shape how representative the findings are for the general population, particularly for those in jobs where health education is less emphasized or resources are limited.



Moreover, the project did not thoroughly address additional influences like stress, sleep, or environmental exposures that can also impact how people age. 



The authors note that further investigation across different groups and regions is needed to confirm how these dietary habits translate to wider communities.



<h2 class="wp-block-heading" id="h-better-health-in-later-life">Better health in later life</h2>



Despite the study’s limitations, scientists believe these observations could inform guidelines that focus on plant-heavy menus while including moderate portions of fish, poultry, and certain dairy products. 



Such balanced recommendations might help preserve independence by cutting back on diseases and supporting stable brain and muscle function in later life.



Eventually, specialists may consider genetic factors and personal preferences to tailor meal plans for individuals, aiming to optimize health at every life stage. 



Combined with better access to wholesome foods in workplaces, schools, and local markets, this approach might support millions in aging with fewer setbacks and more comfort.



<h2 class="wp-block-heading" id="h-midlife-eating-for-healthy-aging">Midlife eating for healthy aging</h2>



Some experts suggest gradually replacing sugary drinks with water or tea, and picking whole grains over refined bread or pasta. 



Even small steps, such as cooking more meals at home and keeping an eye on salt content, can shift eating habits toward healthier patterns.



Others highlight the advantage of planning grocery lists around staples like leafy greens, nuts, and lean proteins to curb impulse buys that derail good intentions. A simple focus on minimally processed items appears to go a long way in creating a diet that supports healthy aging.



The study is published in <a href="https://www.nature.com/articles/s41591-025-03570-5" target="_blank" rel="noreferrer noopener">Nature Medicine</a>.



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Eating better in midlife helps you age with strength

Healthy eating has always been a hotly debated topic, but...

For centuries, sharks have stirred fear and fascination. They glide through water with quiet power. Unlike whales or dolphins, they never seem to speak. Scientists assumed that sharks lived in a world of silence - masters of stealth with no sound.



That idea was rooted in biology. <a href="https://www.earth.com/news/one-third-of-shark-species-face-extinction-despite-fishing-bans/" target="_blank" rel="noreferrer noopener">Sharks</a> lack swim bladders, organs that help many fish produce sound. 



They also don’t have vocal cords or specialized structures like drumming muscles. So the conclusion felt safe: sharks don’t make noise.



But nature is full of surprises. A recent discovery made at the University of Auckland's <a href="https://www.auckland.ac.nz/en/science/about-the-faculty/university-reserves/leigh-marine-laboratory.html" target="_blank" rel="noreferrer noopener">Leigh Marine Laboratory</a> has rewritten what we know about these ancient predators. 



Sharks might not be voiceless after all.



<h2 class="wp-block-heading" id="h-the-first-recorded-shark-sounds">The first recorded shark sounds</h2>



In a study published in Royal Society Open Science, <a href="https://rs.figshare.com/articles/media/Data_1_from_Evidence_of_active_sound_production_by_a_shark/28596448?backTo=%2Fcollections%2FSupplementary_material_from_Evidence_of_active_sound_production_by_a_shark_%2F7720015&amp;file=52990585" target="_blank" rel="noreferrer noopener">scientists shared the first known recordings</a> of active sound production by sharks. 



The species involved, the rig shark (Mustelus lenticulatus), is a small, bottom-dwelling shark native to New Zealand.



During routine hearing experiments, ten juvenile rig <a href="https://www.earth.com/news/chemical-clues-from-old-shark-jaws-reveal-diets-and-habitats/" target="_blank" rel="noreferrer noopener">sharks</a> produced distinct clicking sounds when handled underwater. These weren’t random splashes or incidental noise. They were consistent, sharp clicks — deliberate and audible.



"Sharks have sensory systems that are more refined than their hearing, like their electroreceptors, their smell, and the way they propel themselves through the water… But I think the original notion that we had that sound isn't important at all is also likely not true," said Carolin Nieder, lead author of the study.



<h2 class="wp-block-heading" id="h-clicks-as-stress-or-warning-signals">Clicks as stress or warning signals</h2>



The clicks didn’t happen while the <a href="https://www.earth.com/news/why-some-great-hammerhead-sharks-rarely-leave-home/" target="_blank" rel="noreferrer noopener">sharks</a> swam freely. They didn’t appear during feeding or rest. They only occurred when the sharks were briefly handled. Most clicks happened in the first ten seconds of handling and dropped off after that.



This suggests the sounds may be a reaction to stress. The sharks could be trying to defend themselves or confuse potential predators. Some clicks coincided with physical movements, like swaying or sudden bends. Others came with no visible movement.



The researchers counted an average of nine clicks per shark in a 20-second window. About three-quarters of those clicks were short, single-pulse bursts. The remaining were double-pulse clicks, produced in rapid succession.



“Maybe they weren't afraid for their lives anymore,” Nieder said, noting the decline in clicks over time. This behavior may resemble a natural escape tactic in the wild, used as a quick distraction.



<h2 class="wp-block-heading" id="h-teeth-not-vocal-cords">Teeth, not vocal cords</h2>



So how do <a href="https://www.earth.com/news/sharks-may-benefit-from-rising-temperatures-but-not-from-rising-co2/" target="_blank" rel="noreferrer noopener">sharks</a> make these sounds without sound-producing organs? The team examined this closely. Using microCT scans and detailed dissections, the researchers studied the cranial structure of the rig shark. The teeth emerged as the most likely mechanism.



Rig sharks have blunt, interlocking teeth arranged like flat plates. These teeth snap together during rapid jaw movements. This snapping action likely creates the broadband clicks observed in the study.



The sounds recorded had an average duration of 48 milliseconds, with frequencies between 2.4 and 18.5 kHz. 



Most clicks peaked around 9.6 kHz, far above the rig’s hearing threshold, which tops at around 800 Hz. Yet, the first burst of each click contained low frequencies that might be audible to the sharks themselves.



<h2 class="wp-block-heading" id="h-are-these-shark-sounds-meaningful">Are these shark sounds meaningful?</h2>



The purpose of the clicks remains uncertain. Are they a biological signal - a warning, alarm, or defensive cry? Or are they simply a byproduct of muscle contractions and jaw tension under stress?



The study notes that rigs did not produce sounds during other behaviors, like swimming or feeding. This supports the idea that the clicking is linked to disturbance, not daily communication.



Still, comparisons with other fish species are revealing. Teleost fish, like cod and piranhas, often emit clicks when threatened or approached by predators. These “predator-related” sounds serve no obvious communicative role but may momentarily confuse or startle attackers.



<h2 class="wp-block-heading" id="h-similar-sounds-in-other-species">Similar sounds in other species</h2>



This discovery also echoes recent findings in rays. Since 2022, several studies have reported click-like sounds in stingrays and skates when divers approached. 



Species like the mangrove whipray and the blonde ray produce sharp broadband clicks, seemingly in reaction to disturbance.



These clicks share many traits with the rig’s clicks: short duration, high frequency, and apparent links to stress. While the anatomical mechanisms may differ, the pattern is striking.



In rays, the movement of spiracles and fins has been observed during sound production. In rigs, however, no clear body movement could be linked directly to the clicks. This raises the need for better underwater observation - perhaps through close-up video - to pinpoint exactly how the sound is made.



<h2 class="wp-block-heading" id="h-not-all-sharks-click">Not all sharks click</h2>



Interestingly, not all <a href="https://www.earth.com/news/mediterranean-sharks-face-growing-threats-despite-conservation-efforts/" target="_blank" rel="noreferrer noopener">sharks</a> show this behavior. The study tested three dusky smoothhounds (Mustelus canis), close relatives of the rig. These sharks, when handled under the same conditions, produced no clicks.



This may point to differences in species behavior, evolutionary paths, or simply varying sensitivity to human presence. The dusky smoothhounds had been in captivity longer, which might explain their lack of response.



The researchers noted that Mustelus as a genus includes many species with similar tooth shapes. It’s possible that other species may also produce clicks under the right circumstances.



<h2 class="wp-block-heading" id="h-can-rig-sharks-hear-their-own-sounds">Can rig sharks hear their own sounds?</h2>



This question remains unresolved. Rigs are most sensitive to very low frequencies, far below the peak of their clicks. Yet, each click begins with a powerful burst that includes frequencies under 1 kHz. These lower frequencies may fall within the shark’s hearing range.



Whether the clicks carry a message for other sharks is unclear. But it’s possible the clicks aren’t meant for sharks at all. The energy-rich sounds could affect predators with better hearing, like toothed whales or large marine mammals. 



Some fish also produce similar sounds that deter or confuse predators, even if they aren’t always effective.



<h2 class="wp-block-heading" id="h-new-voices-from-the-deep">New voices from the deep</h2>



For years, researchers assumed that sharks lacked the ability - or need - to make sound. This study shifts that narrative. It reveals not only a sound, but a potential signal - a cry, a warning, or perhaps an instinctive snap.



The rig shark now holds the title of the first confirmed sound-producing shark. And its clicks may not be alone for long. As scientists look closer, more species may reveal their hidden voices.



In the quietest corners of the ocean, even sharks might have something to say.



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<a href="https://rs.figshare.com/articles/media/Data_1_from_Evidence_of_active_sound_production_by_a_shark/28596448?backTo=%2Fcollections%2FSupplementary_material_from_Evidence_of_active_sound_production_by_a_shark_%2F7720015&amp;file=52990585" target="_blank" rel="noreferrer noopener">Click this link to hear the noises made by these sharks during the hunt...</a>



The study is published in the journal <a href="https://royalsocietypublishing.org/doi/10.1098/rsos.242212" target="_blank" rel="noreferrer noopener">Royal Society Open Science</a>.&nbsp;



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Sharks recorded making terrifying sounds while hunting - despite not having vocal cords

For centuries, sharks have stirred fear and fascination. They glide...

Population genetics can reveal surprising insights about the ancestry of any group, often challenging assumptions that have persisted for centuries. Japan is a prime example, with many believing its people descend from only two main lines of ancestry. 



New evidence now indicates that there may be a third strand woven into the country’s genetic heritage. Researchers are examining DNA clues and clinical data to piece together a bigger story, and the results are shaking up conventional wisdom on what it really means to be Japanese.



A paper published in the journal Science Advances presented findings that suggest a far more intricate <a href="https://www.earth.com/news/recreating-the-face-of-dragon-man-harbin-skull-denisovans-an-ancient-human-cousin/" target="_blank" rel="noreferrer noopener">genetic tapestry</a> is involved in the ultimate ancestry of people in Japan than previously thought. 



The project behind this discovery is led by experts who investigated thousands of samples to paint a detailed picture of ancestry. 



After sifting through these clues, RIKEN’s Chikashi Terao and colleagues propose that a third group, the so-called Emishi people, is part of this fascinating blend.



Terao, who headed the study at RIKEN's <a href="https://www.riken.jp/en/research/labs/ims/" target="_blank" rel="noreferrer noopener">Center for Integrative Medical Sciences</a>, explains, “Our analysis revealed Japan's subpopulation structure on a fine scale, which is very beautifully classified according to geographical locations in the country.”



<h2 class="wp-block-heading" id="h-fresh-perspective-on-japanese-ancestry">Fresh perspective on Japanese ancestry</h2>



Researchers used whole-genome sequencing to analyze genetic information from more than 3,200 people across seven regions of Japan. 



This approach zooms in on all three billion DNA base-pairs, offering a much more comprehensive view compared to previous methods. 



Terao says, “Whole-genome sequencing gives us the chance to look at more data, which helps us find more interesting things.”



By examining the data, the team pinpointed differences that track with older population groups. Traditional narratives described only two main ancestral lines: the Jomon and the <a href="https://www.earth.com/news/dna-study-reveals-secrets-of-weedy-rice-invasion/" target="_blank" rel="noreferrer noopener">rice-farming</a> migrants from east Asia. 



The latest results identify a third source in the mix - people with connections to northeast Asia known as the Emishi. 



One key aspect of this research is the focus on subtle markers that illuminate how these historical groups spread out across the islands.



<h2 class="wp-block-heading" id="h-japan-s-ancestry-gets-clues-from-jewel">Japan's ancestry gets clues from JEWEL</h2>



The Japanese Encyclopedia of Whole-Genome/Exome Sequencing Library (JEWEL) combines genetic material with related medical and family information. 



The researchers gathered this data to explore health links and ancestry, creating a resource that also sheds light on how certain diseases appear in distinct areas. 



Terao remarks, “We reasoned that rare variants can sometimes be traced back to specific ancestral populations, and could be informative in revealing fine-scale <a href="https://www.earth.com/news/timeline-early-humans-great-migration-reached-america-challenged-again/" target="_blank" rel="noreferrer noopener">migration patterns</a> within Japan.”



According to the analysis, Jomon ancestry remains most prominent in Okinawa, appearing in 28.5% of the samples studied there, while it is lowest in western Japan at just 13.4%. 



Meanwhile, the study found that individuals in western regions have closer connections to Han Chinese people. 



The influx of migrants from east Asia between the year 250 and year 794 correlates with that finding. Emishi-related lineage appears strongest in the northeast, gradually dwindling as one moves westward.



<h2 class="wp-block-heading" id="h-rare-variants-and-their-role">Rare variants and their role</h2>



The study did more than trace broad patterns of ancestry. It also drilled down into uncommon gene variations to discover their potential involvement in various conditions. 



One particular variant of a gene called PTPRD has the potential to be highly damaging because it could be linked with hypertension, kidney failure, and myocardial infarction, according to Xiaoxi Liu, a senior scientist in Terao’s lab and the first author of the research. 



Additionally, significant incidences of variants in the GJB2 and ABCC2 genes were documented, tying them to hearing loss and chronic liver disease.



These clues demonstrate the practical potential of such extensive DNA surveys. By mapping rare changes, the researchers gain a sharper understanding of health outcomes, which may eventually guide new approaches to diagnosis or treatment. 



The JEWEL database thus provides a framework for aligning genetic signals with real-world health profiles.



<h2 class="wp-block-heading" id="h-clues-from-neanderthals-and-denisovans">Clues from Neanderthals and Denisovans</h2>



The project also examined segments inherited from <a href="https://www.earth.com/news/tinshemet-cave-more-evidence-neanderthals-and-early-humans-interacted-socially/" target="_blank" rel="noreferrer noopener">Neanderthals</a> and <a href="https://www.earth.com/news/mysterious-denisovan-species-humans-lived-undisturbed-tibetan-plateau-160000-years/" target="_blank" rel="noreferrer noopener">Denisovans</a>, two archaic human groups that intermixed with Homo sapiens millennia ago. 



Terao states, “We are interested in why ancient genomes are integrated and kept in modern human DNA sequences.” 



The team identified 44 ancient DNA regions present in Japanese people, many unique to East Asians. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/03/japanese_ancestry_introgressed-chart_credit-RIKEN_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2025/03/japanese_ancestry_introgressed-chart_credit-RIKEN_1s.webp" alt="Introgressed sequences from archaic Neanderthals or Denisovans in the Japanese population. Click to enlarge. Credit: RIKEN" class="wp-image-1963362"/></a><figcaption class="wp-element-caption">Introgressed sequences from archaic Neanderthals or Denisovans in the Japanese population. Click to enlarge. Credit: RIKEN</figcaption></figure>



Among these was a Denisovan-derived segment within the NKX6-1 gene, which may influence how individuals respond to semaglutide, a drug used to treat type 2 diabetes.



They also located 11 Neanderthal-derived segments possibly tied to several conditions, including coronary artery disease, prostate cancer, and rheumatoid arthritis. 



Researchers in other parts of the world have shown that <a href="https://www.earth.com/news/neanderthal-genes-make-you-more-of-a-morning-person/" target="_blank" rel="noreferrer noopener">archaic DNA</a> occasionally grants advantages in extreme environments or impacts susceptibility to illness. 



This new study adds fresh details to the ongoing search for connections between ancient genes and modern-day health.



<h2 class="wp-block-heading" id="h-japan-ancestry-and-human-health">Japan, ancestry, and human health</h2>



Scientists point out that large-scale genetic investigations have mostly centered on European samples. Terao is keen to expand the reach of JEWEL by including more DNA profiles from Asia and beyond. 



This broader approach could highlight unique markers and conditions that are otherwise overlooked. “We’d like to connect population differences with differences in genetics,” he observes.



Population research of this magnitude promises to clarify how certain traits, disorders, and susceptibilities arise. 



It may also help fine-tune healthcare for specific communities by showing which variants are most influential. At the same time, it shows that no population is as uniform as once believed. 



The new evidence highlights how three ancestral groups contributed to the current mosaic in Japan, blending the histories of the Jomon, east Asian migrants, and the Emishi people into a more complete picture of Japan’s past.



The full study was published in the journal <a href="https://www.science.org/doi/10.1126/sciadv.adi8419" target="_blank" rel="noreferrer noopener">Science Advances</a>.



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Who are the Japanese people? DNA study results upend previous beliefs

Population genetics can reveal surprising insights about the ancestry of...

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



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



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



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



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



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



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



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



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



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

Is chocolate the next nutritional powerhouse?

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

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



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



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



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

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



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



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



Video/ Image Credit: American Chemical Society&nbsp;



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



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

Flu viruses are more flexible than expected

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



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



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



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



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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



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



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



Video Credit: American Chemical Society&nbsp;



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



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

Detecting mercury contamination with the tap of a finger

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



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



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



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



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



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



Video/ Image Credit: European Space Agency&nbsp;



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



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

Kainji Lake in north central Nigeria

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Wild hog in the Namib desert in Namibia Photo Credit: Photofex-AUT

Wild Hog

Black Widow Spider -Female, male and egg sac Photo Credit: Mark_Kostich

Wild Hog

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