<p>Today's <strong>Image of the Day</strong> from the European Space Agency features a Copernicus Sentinel-2 photograph of Lake Maracaibo, located in the northwestern part of Venezuela. The lake is a significant geographical and ecological feature of South America. </p>



<p>Lake Maracaibo is often considered more of a tidal bay due to its direct connection to the Caribbean Sea through the Tablazo Strait. It is one of the oldest lakes on Earth, formed approximately 36 million years ago.</p>



<p>"With an area of over 13,000 sq km, Lake Maracaibo is generally considered the largest lake in South America, although by some estimates it should be considered an inlet of the Caribbean Sea since much of its water is brought in by its direct connection to the ocean," explained <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.</p>



<p>"As a result, the water in the northern part of the lake is rather brackish, while the southern waters are fresh, owing to the many rivers that flow into the lake. The biggest, the Catatumbo River, can be seen entering the lake from southwest, where a large amount of sediment carried by the river appears as a yellowish plume."</p>



<h2 class="wp-block-heading" id="h-the-catatumbo-lightning">The Catatumbo lightning</h2>



<p>The lake is renowned for a unique weather phenomenon - the Catatumbo lightning. This natural spectacle occurs primarily where the Catatumbo River meets the <a href="https://www.earth.com/news/wildfire-smoke-has-affected-almost-every-lake-in-north-america/" target="_blank" rel="noreferrer noopener">lake</a>.</p>



<p>Known as the most persistent lightning storm in the world, it produces frequent and dramatic flashes of lightning, illuminating the night sky for an average of 260 nights per year.</p>



<p>These storms generate thousands of lightning strikes in a single night, making the region one of the most electrified places on the planet. </p>



<p>The phenomenon is so intense that it has been recognized by the Guinness World Records as the place with the highest <a href="https://www.earth.com/news/lightning-on-earth-can-influence-the-weather-in-space/" target="_blank" rel="noreferrer noopener">lightning</a> activity.</p>



<p>Scientists believe the lightning is influenced by the area's geography and climate, including the warm air rising from the lake and its surrounding mountains.</p>



<h2 class="wp-block-heading" id="h-economical-significance-of-lake-maracaibo">Economical significance of Lake Maracaibo </h2>



<p>Lake Maracaibo plays an important role in Venezuela’s economy, as it lies atop vast reserves of crude oil.</p>



<p>The discovery of petroleum in the early 20th century transformed the region into a major oil-producing area, leading to the establishment of numerous oil rigs and platforms. </p>



<p>However, this economic activity has come at a cost. <a href="https://www.earth.com/news/half-of-the-worlds-largest-lakes-are-losing-their-resilience/" target="_blank" rel="noreferrer noopener">Pollution</a> from oil spills, industrial waste, and agricultural runoff has significantly degraded the lake's ecosystem.</p>



<p>The appearance of a green, slimy algae known as Lemna has further exacerbated environmental concerns, threatening marine life and the livelihoods of local communities.</p>



<h2 class="wp-block-heading" id="h-cultural-ties-to-lake-maracaibo">Cultural ties to Lake Maracaibo </h2>



<p>The cultural significance of Lake Maracaibo is deeply rooted in the traditions and lifestyle of the Indigenous Añu people, who have inhabited its shores for centuries. The Añu, also known as Paraujano, are known for their distinctive stilt houses, called palafitos.</p>



<p>These wooden structures are built directly over the water, connected by walkways or small boats, allowing the Añu to live harmoniously with their aquatic environment. The architectural style of these stilt houses inspired the early Spanish explorers to nickname the region "The Venice of the Americas."</p>



<p>The Añu's way of life is closely tied to the lake. They rely on <a href="https://www.earth.com/news/sustainable-fishing-must-be-redefined-to-halt-ocean-destruction/" target="_blank" rel="noreferrer noopener">fishing</a> as a primary source of food and income, using traditional methods passed down through generations.</p>



<p>For the Añu, the <a href="https://www.earth.com/news/wildfire-smoke-significantly-impacts-lake-ecosystems/" target="_blank" rel="noreferrer noopener">lake</a> is more than a resource; it is a spiritual and cultural cornerstone, shaping their identity and daily practices.</p>



<p>However, modernization and environmental challenges have disrupted their traditional lifestyle. The oil industry’s expansion around Lake Maracaibo has led to significant environmental degradation, which threaten the lake's biodiversity and the Añu’s primary sources of sustenance. </p>



<h2 class="wp-block-heading" id="h-lake-maracaibo-and-venezuelan-history">Lake Maracaibo and Venezuelan history</h2>



<p>Lake Maracaibo also played a pivotal role in Venezuelan history, particularly during the Battle of Lake Maracaibo in 1823. </p>



<p>This naval battle was a decisive conflict in Venezuela’s war for independence from Spain and marked one of the final military engagements of the South American liberation movements led by figures like Simón Bolívar.</p>



<p>Today, the lake represents a remarkable blend of natural beauty, industrial significance, and cultural heritage. </p>



<h2 class="wp-block-heading" id="h-ongoing-conservation-efforts">Ongoing conservation efforts </h2>



<p>Ongoing efforts aim to harmonize ecological conservation with economic development, as both local and global stakeholders acknowledge the need to protect this extraordinary environment for generations to come.</p>



<p>Efforts to preserve the Añu culture and the lake's ecosystem have been initiated by local and international organizations. These initiatives focus on promoting sustainable development, preserving Indigenous languages and traditions, and mitigating the environmental damage caused by industrial activities. </p>



<p>Despite these challenges, the Añu have shown remarkable resilience, maintaining their cultural identity and advocating for their rights and the health of their ancestral lands.</p>



<p><em>Image Credit: ESA</em></p>



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Lake Maracaibo: One of the most electrified places on the planet

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

<p>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. The image was captured on August 4, 2024 by the Landsat 8 satellite.</p>



<p>“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>.</p>



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



<p>“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;</p>



<p>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.</p>



<p>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.”</p>



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



<p>“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.</p>



<p>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.</p>



<p>“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.</p>



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



<p>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;</p>



<p>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.</p>



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



<p>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;</p>



<p>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.</p>



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



<p>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;</p>



<p>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.</p>



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



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



<p>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>.</p>



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



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



<p>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.</p>



<p>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.</p>



<p>Image Credit: NASA Earth Observatory</p>



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Retreating glaciers and expanding meltwater lakes in Alaska

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

<p>Today's Image of the Day from NASA Earth Observatory features the Gobi Altai Mountains and neighboring plains covered in snow and illuminated by sunlight. </p>



<p>The photograph was captured on January 25, 2024 as the International Space Station (ISS) passed over central Mongolia.</p>



<h2 class="wp-block-heading" id="h-mountain-peaks-and-plains">Mountain peaks and plains</h2>



<p>“Late-afternoon sunlight casts long shadows of mountain peaks onto the plains below. Numerous steep gullies cut into the massif, or mass of mountains, whose rugged appearance contrasts with the flat plains stretching along the top of the image,” said <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA</a>. “The plains are a semidesert grassland, or steppe, which provides pasture for livestock herders in the region.”</p>



<p>“The grassland surrounding the massif is classified by scientists as a cold semidesert. At an elevation of about 1,250 meters, annual temperatures are much lower there than in the mountains. The highest peak in the massif, Ikh Bogd (also known as Tergun Bogd), reaches nearly 4,000 meters.”&nbsp;</p>



<p>According to NASA, the climate on the peaks is classified as a polar tundra because the average annual temperature is below freezing. "Asia’s main tundra zone is located in Siberia, along the coast of the Arctic Ocean, 2,800 kilometers (1,750 miles) to the north.”</p>



<h2 class="wp-block-heading" id="h-harsh-winters-and-livestock-in-mongolia">Harsh winters and livestock in Mongolia</h2>



<p>Harsh <a href="https://www.earth.com/news/why-winters-are-getting-colder-while-world-is-getting-warmer/" target="_blank" rel="noreferrer noopener">winters</a> in Mongolia, locally known as "dzud," pose significant challenges for livestock and the herders who depend on them for their livelihood. These winters can be particularly severe, characterized by extreme cold, heavy snowfall, and ice, which can block access to grazing grounds, leaving animals without enough food.&nbsp;</p>



<p>The cold temperatures and nutritional shortages result in high mortality rates among livestock, which are crucial to the Mongolian economy and the nomadic lifestyle of many of its people.</p>



<p>The impact of these harsh winters extends beyond immediate animal welfare. As <a href="https://www.earth.com/news/bacteria-in-livestock-are-major-drivers-of-antibiotic-resistance/" target="_blank" rel="noreferrer noopener">livestock</a> numbers dwindle, herders face financial hardships, and the ripple effects can be felt throughout the entire community.&nbsp;</p>



<p>To combat these challenges, various strategies have been employed, including the development of better forecasting and early warning systems, the stockpiling of fodder, and improved veterinary care. These measures aim to strengthen the resilience of herding communities and ensure the survival of their livestock during Mongolia's most challenging seasons.</p>



<h2 class="wp-block-heading" id="h-diverse-wildlife-of-mongolia">Diverse wildlife of Mongolia</h2>



<p>Mongolia is renowned for its diverse wildlife, adapted to its unique landscapes ranging from vast steppes to rugged <a href="https://www.earth.com/news/mountains-both-carbon-sinks-and-carbon-sources/" target="_blank" rel="noreferrer noopener">mountains</a> and arid deserts. Among the most iconic species is the Bactrian camel, native to the region and crucial to nomadic herders.&nbsp;</p>



<p>The resilient Mongolian horse, integral to local culture, is celebrated for its endurance across the vast, open landscapes. Predators such as the snow leopard roam the high altitudes, playing a key role in the ecosystem, while the elusive Gobi bear survives in the sparse vegetation of the Gobi Desert.</p>



<p>The steppes are home to the fast-moving Mongolian gazelle and the critically endangered saiga antelope, known for its distinctive nose. The mountains support populations of argali sheep, the world's largest wild sheep, and the ibex, which has mastered the art of navigating rocky terrains. </p>



<h2 class="wp-block-heading" id="h-valley-of-lakes">Valley of Lakes</h2>



<p>“Part of a small dry lake appears in the top left of the image. In wetter years, water from this lake feeds Orog Lake (also photographed by astronauts), out of frame to the upper right. This and other nearby lakes are part of the Valley of Lakes waterfowl conservation habitat, protected as a Ramsar site,” noted NASA.</p>



<p>The Valley of Lakes is known for its expansive <a href="https://www.earth.com/news/the-potential-of-tidal-wetlands-as-blue-carbon-ecosystems/" target="_blank" rel="noreferrer noopener">wetlands</a> and diverse ecosystems that support a variety of bird species, especially migratory waterfowl. This area serves as a crucial stopover for birds during their migration periods, providing them with essential resources such as food and shelter.&nbsp;</p>



<p>The conservation efforts in the Valley of Lakes focus on maintaining and restoring these <a href="https://www.earth.com/news/coastal-wetlands-are-inching-closer-to-extinction-as-the-world-heats-up/" target="_blank" rel="noreferrer noopener">wetlands</a> to ensure they continue to offer a safe haven for waterfowl. These efforts include controlling invasive plant species that threaten the natural vegetation and managing water levels to create optimal conditions for bird populations.&nbsp;</p>



<p>Education and community involvement are also key components of the conservation strategy, aiming to raise awareness about the importance of these habitats and encourage sustainable practices that help protect the local wildlife.</p>



<p>Image Credit: NASA Earth Observatory&nbsp;</p>



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Mountain peaks and plains of central Mongolia 

<p>Today's <strong>Image of the Day</strong> 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. </p>



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



<p>"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>.</p>



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



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



<p>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;</p>



<p>"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."</p>



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



<p>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.</p>



<p>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.</p>



<p>"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."</p>



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



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



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



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



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



<p>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.</p>



<p>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.</p>



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



<p>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.</p>



<p>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. </p>



<p>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.</p>



<p>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. </p>



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



<p>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. </p>



<p>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.</p>



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



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Spiral galaxy NGC 1559 is a loner in outer space

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



<p>NGC 3783 is also the most prominent of a galaxy group (by the same name) that contains 47 galaxies. </p>



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



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



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



<h2 class="wp-block-heading" id="h-hd-101274-a-blue-giant-star">HD 101274: A blue giant star</h2>



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



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



<p>HD 101274 is categorized as a blue giant star, characterized by its high temperature and luminosity. </p>



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



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



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



<p>The spectral and photometric observations of such stars can provide valuable insights into the characteristics of their atmospheres, internal structures, and the processes occurring within and around them.</p>



<h2 class="wp-block-heading" id="h-bright-central-region-of-ngc-3783">Bright central region of NGC 3783</h2>



<p>One of the most interesting aspects of NGC 3783 is that it harbors an active galactic nucleus, meaning its central region is exceptionally luminous, likely due to the presence of a supermassive black hole. This black hole is actively accreting material, which emits a substantial amount of radiation as it spirals inward and heats up.</p>



<p>The galaxy is particularly known for its bright central region and has been studied extensively in the ultraviolet and X-ray light spectra to understand better the properties of the accretion disk around the black hole and the complex dynamics of the material surrounding it. These studies are crucial for understanding the physics of active galactic nuclei and the role they play in <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">galaxy evolution</a>.</p>



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



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



<h2 class="wp-block-heading" id="h-more-about-the-ngc-3783-galaxy-group">More about the NGC 3783 galaxy group</h2>



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



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



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



<p>Image Credit: ESA/Hubble &amp; NASA</p>



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Luminous galaxy NGC 3783 and a blue giant star

This,Man-made,Vehicle,Reached,A,Record,Speed,Of,635,Thousand

<p>NASA’s Parker Solar Probe is set to achieve its most dangerous feat yet tomorrow, December 24, 2024. After a six-year journey of spiraling closer to the star at the heart of our solar system, the spacecraft is expected to come within 3.8 million miles of the Sun’s surface. </p>



<p>This tiny distance in cosmic terms lets scientists capture a new type of information, revealing secrets about solar winds, extreme heat, and magnetic fields.</p>



<h2 class="wp-block-heading" id="h-solar-probe-on-the-sun-s-doorstep">Solar probe on the Sun's doorstep</h2>



<p>Engineers have spent years carefully adjusting <a href="https://blogs.nasa.gov/parkersolarprobe/" target="_blank" rel="noreferrer noopener">Parker’s flight path</a> using multiple Venus gravity assists. These flybys reshape the spacecraft’s orbit and tighten its looping path around the Sun.<br><br>“This is one example of NASA’s bold missions, doing something that no one else has ever done before to answer longstanding questions about our universe,” explained <a href="https://science.nasa.gov/people/dr-arik-posner/" target="_blank" rel="noreferrer noopener">Arik Posner</a>, Parker Solar Probe program scientist at NASA Headquarters, describing this mission’s significance.</p>



<p>Ever since the launch in 2018, Parker’s main goal has been to study the Sun’s outer atmosphere, known as the corona. Tomorrow’s approach, often called <a href="https://cneos.jpl.nasa.gov/glossary/perihelion.html" target="_blank" rel="noreferrer noopener">perihelion</a>, marks a new milestone in that quest.<br><br>The probe moves at speeds around 430,000 miles per hour, faster than any other spacecraft. At such high velocity, it can swing around our star without getting swallowed.<br><br>Even so, mission managers won’t receive immediate updates once Parker hits its closest point because signals cannot travel through the intense solar environment.</p>



<h2 class="wp-block-heading" id="h-extreme-heat-and-lasting-protection">Extreme heat and lasting protection</h2>



<p>What sets Parker apart is its resilient heat shield. This 4.5-inch-thick carbon-composite barrier enables the spacecraft’s instruments to continue functioning in an environment where temperatures can reach roughly 2,500 degrees Fahrenheit.<br><br>Despite the harsh surroundings, the precious science instruments remain near room temperature, thanks to expert engineering by Johns Hopkins University Applied Physics Laboratory (<a href="https://parkersolarprobe.jhuapl.edu/" target="_blank" rel="noreferrer noopener">APL</a>).</p>



<p>During every close approach, Parker is pelted by gusts of solar wind and bathed in radiation. Still, it keeps sending back readings about magnetic fields, <a href="https://www.plasmacoalition.org/plasma_writeups/solar_plasmas.pdf" target="_blank" rel="noreferrer noopener">plasma</a> behavior, and energetic <a href="https://www.swpc.noaa.gov/phenomena/solar-radiation-storm#:~:text=Solar%20radiation%20storms%20occur%20when,of%20the%20speed%20of%20light." target="_blank" rel="noreferrer noopener">particles</a>.<br><br>The probe’s data illuminates reasons behind the corona’s blazing heat, which can climb into the millions of degrees, significantly hotter than the visible surface of the Sun. Such puzzling behavior has fascinated scientists for decades.</p>



<h2 class="wp-block-heading" id="h-chasing-the-solar-wind-s-origins">Chasing the solar wind’s origins</h2>



<p>Solar wind, a stream of charged particles flowing away from the Sun at speeds topping one million miles per hour, plays a major role in <a href="https://science.nasa.gov/sun/what-is-the-solar-wind/">space weather</a>. </p>



<p>By skimming through the corona, Parker records fresh evidence of how these particles speed up and scatter across the solar system.<br><br>The answers may help experts forecast disturbances that affect satellites and astronaut safety. Surges of these charged particles can disable communication systems or even disrupt power grids on Earth.</p>



<p>For researchers, big questions remain. How does the <a href="https://science.nasa.gov/sun/what-is-the-solar-wind/">solar wind</a> pick up its pace so dramatically? Is there a specific region in the corona that triggers bursts of fast-moving particles? </p>



<p>Parker’s measurements bring us closer to unraveling these mysteries. Officials at NASA say that by tomorrow’s approach, new layers of data will help them see patterns not possible to detect from a greater distance.</p>



<h2 class="wp-block-heading" id="h-solar-probe-and-the-sun-s-active-cycle">Solar probe and the Sun's active cycle</h2>



<p>The Sun moves through an 11-year activity cycle. Right now, it is in an active phase, meaning increased sunspots, <a href="https://www.earth.com/news/secondary-peak-extreme-geomagnetic-solar-storm-expected-today/" target="_blank" rel="noreferrer noopener">solar flares</a>, and <a href="https://www.swpc.noaa.gov/phenomena/coronal-mass-ejections" target="_blank" rel="noreferrer noopener">coronal mass ejections</a>. </p>



<p>Researchers are tracking not only Parker’s journey but also the Sun’s changing patterns. Sometimes these outbursts interact with Earth’s magnetosphere and spark colorful auroras, even in places unused to such displays.<br><br>And although most solar weather events are harmless for life on Earth, severe storms can interfere with GPS systems or satellites.</p>



<p>This is why Parker’s findings are so relevant. Gaining a better understanding of how energetic solar events begin could lead to timelier warnings, giving operators on Earth a heads-up to power down sensitive instruments or adjust satellite orbits.</p>



<h2 class="wp-block-heading" id="h-paying-tribute-to-eugene-parker">Paying tribute to Eugene Parker</h2>



<p>In 2017, NASA renamed the probe after <a href="https://news.uchicago.edu/story/eugene-parker-legendary-figure-solar-science-and-namesake-parker-solar-probe-1927-2022">Dr. Eugene N. Parker</a>, the first person to predict the solar wind in the 1950s. He introduced key ideas about how stars interact with their surroundings.<br><br>The mission’s name honors his influential work. Dr. Parker passed away in 2022, but his legacy continues. </p>



<p>The data this spacecraft is sending back not only expands knowledge of <a href="https://www.earth.com/news/tracing-solar-wind-directly-to-its-source-for-the-first-time/" target="_blank" rel="noreferrer noopener">solar physics</a> but also shows how correct Dr. Parker’s early theories were.</p>



<h2 class="wp-block-heading" id="h-record-setting-solar-probe-flyby">Record-setting Solar Probe flyby</h2>



<p>Mission operations expect Parker to reach perihelion at 6:53 a.m. EST on December 24. </p>



<p>At that time, the spacecraft will run autonomously, and engineers at APL will wait until December 27 for a beacon tone confirming a safe passage around the Sun.<br><br>“No human-made object has ever passed this close to a star, so Parker will truly be returning data from uncharted territory. We’re excited to hear back from the spacecraft when it swings back around the Sun,” explained <a href="https://parkersolarprobe.jhuapl.edu/News-Center/Show-Article.php?articleID=205" target="_blank" rel="noreferrer noopener">Nick Pinkine</a>, Parker Solar Probe mission operations manager. </p>



<p>When that update arrives, scientists will study Parker’s recent measurements to identify potential clues about solar wind origins and coronal heating.<br><br>Each orbit is another chance to witness the scorching conditions near our star. At the same time, the probe helps refine predictions about solar eruptions that might drive future storms toward Earth.</p>



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



<p>Beyond the scientific breakthroughs, Parker’s success can have practical benefits for technology we rely on every day. Our society depends on GPS signals and stable power systems, and <a href="https://www.earth.com/news/team-creates-video-showing-the-sun-in-gamma-rays-over-a-14-year-period/" target="_blank" rel="noreferrer noopener">major solar events</a> can disrupt both.<br><br>By learning how to anticipate strong solar winds or flares, experts might one day keep satellites out of harm’s way or shield power grids from unexpected surges.</p>



<p>Tomorrow’s close approach continues a streak of remarkable achievements for NASA. As Parker zips through the corona, it gathers observations that no other mission could obtain.<br><br>The craft appears ready for another sizzling pass, thanks to the robust thermal design and careful planning. </p>



<p>Whether it’s helping forecast solar tempers or refining our knowledge of basic astrophysical processes, Parker remains on track to change the way we see the Sun.</p>



<p>Learn more about <a href="https://science.nasa.gov/mission/parker-solar-probe/" target="_blank" rel="noreferrer noopener">NASA's Parker Solar Probe here...</a></p>



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Spacecraft will fly through the Sun's atmosphere tomorrow for the first time ever

NASA’s Parker Solar Probe is set to achieve its most...

Bright,,Red-dark,Quasar,In,Deep,Space.,Elements,Of,This,Image

<p>Astronomers have identified a remarkable water reservoir hidden in a corner of the cosmos, circling a quasar more than 12 billion light-years away.</p>



<p>At that distance, the light we see today began its journey not too long after the universe itself formed. </p>



<p>The water supply in this distant place is huge, containing the equivalent of about 140 trillion times all the water in Earth’s oceans combined.</p>



<p>This supply is sitting near a supermassive black hole that is about 20 billion times more massive than our sun. </p>



<p><a href="https://www.earth.com/news/oldest-black-hole-ever-discovered-dates-back-to-the-dawn-of-time/" target="_blank" rel="noreferrer noopener">The black hole</a> is surrounded by a quasar named APM 08279+5255, which pumps out as much energy as a thousand trillion suns. </p>



<p>This quasar, according to astronomers, holds the farthest and largest known reservoir of water anywhere in the universe.</p>



<h2 class="wp-block-heading" id="h-quasar-apm-08279-5255-and-its-water">Quasar APM 08279+5255 and its water</h2>



<p>Matt Bradford, a scientist at NASA’s <a href="https://www.jpl.nasa.gov/" target="_blank" rel="noreferrer noopener">Jet Propulsion Laboratory</a> in Pasadena, Calif., leads one of the teams involved in the observations.</p>



<p>“The environment around this quasar is very unique in that it’s producing this huge mass of water,” said Matt Bradford. “It’s another demonstration that water is pervasive throughout the universe, even at the very earliest times.”</p>



<p>Both Bradford’s group and a separate team of astronomers studied APM 08279+5255 and its <a href="https://www.earth.com/news/massive-black-hole-is-seen-taking-a-nap-after-eating-too-much/" target="_blank" rel="noreferrer noopener">black hole</a>, which sits at the center and draws matter inward. </p>



<p>As it does, it warms the surrounding gas and dust, forming an area filled with molecules that have never before been detected at such an immense distance.</p>



<h2 class="wp-block-heading" id="h-understanding-quasars-the-basics">Understanding quasars -- the basics</h2>



<p>Quasars were first noticed more than half a century ago when telescopes revealed puzzling sources of intense brightness in <a href="https://www.earth.com/news/hubble-took-the-closest-ever-image-of-a-quasar-and-captured-some-weird-things/" target="_blank" rel="noreferrer noopener">distant areas of space</a>. </p>



<p>These objects are unlike any ordinary star. They shine brightly from the center of distant galaxies, outshining all their galaxy’s stars combined.</p>



<p>At their heart sit supermassive black holes, millions or billions of times heavier than our sun. As gas and dust spiral in toward one of these black holes, the swirling material heats up and <a href="https://www.earth.com/news/black-hole-jet-crashes-into-an-unidentified-object/" target="_blank" rel="noreferrer noopener">releases energy</a>. </p>



<p>This energy blasts out across all kinds of wavelengths, making quasars some of the brightest, most energetic phenomena ever seen.</p>



<p>Observing quasars helps astronomers understand what the universe looked like long ago, since the light we see now began its journey billions of years in the past. </p>



<p>Quasars can show how galaxies formed, how matter spread out, and how the earliest structures in the cosmos came together.</p>



<p>They can even help map the distribution of matter between galaxies, shining light on the regions that would otherwise remain unseen. </p>



<p>Some quasars also launch <a href="https://www.earth.com/news/black-hole-jets-are-like-million-light-year-long-jedi-lightsabers/" target="_blank" rel="noreferrer noopener">huge jets of high-speed particles</a> that stretch across enormous distances. These jets can affect how stars form, influencing entire neighborhoods of cosmic material.</p>



<h2 class="wp-block-heading" id="h-strange-place-to-find-water">Strange place to find water</h2>



<p>Astronomers observed that water vapor is present in this quasar’s environment. It occupies a region spanning hundreds of light-years, with one light-year at around six trillion miles. </p>



<p>Although the gas is thin by Earth standards, it is surprisingly warm and dense compared to what is typical in places like our <a href="https://www.earth.com/news/milky-ways-black-hole-formed-through-a-merger/" target="_blank" rel="noreferrer noopener">Milky Way</a>.</p>



<p>The temperature hovers around minus 63 degrees Fahrenheit, and the gas is roughly 300 trillion times less dense than Earth’s atmosphere. </p>



<p>Still, it is about five times hotter and tens to hundreds of times denser than the gas seen in normal galaxies. With its unusual conditions, this region stands out as an unexpected find.</p>



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



<p><a href="https://www.earth.com/news/oceans-of-water-vapor-may-be-involved-in-planet-formation/" target="_blank" rel="noreferrer noopener">Water vapor</a> is not just a molecule. Its presence here suggests that the quasar is bathing its environment in radiation that keeps the gas relatively warm. </p>



<p>Astronomers also spotted other molecules, like carbon monoxide, hinting that there is an abundance of raw material that can feed the black hole as it continues to grow.</p>



<p>They estimate that there is enough gas for the <a href="https://www.earth.com/news/largest-map-of-supermassive-black-holes-unveiled/" target="_blank" rel="noreferrer noopener">black hole</a> to increase in size by about six times, although what actually happens next is not certain. </p>



<p>Some of this gas may form new stars, while some might be thrown out into space instead. Either way, these measurements open a window into what conditions were like when the universe was still young.</p>



<h2 class="wp-block-heading" id="h-quasars-water-and-life-s-building-blocks">Quasars, water, and life's building blocks</h2>



<p>Detecting water vapor in such a distant quasar expands our knowledge of how <a href="https://www.earth.com/news/did-the-building-blocks-of-life-replicate-on-their-own/" target="_blank" rel="noreferrer noopener">building blocks</a> appear across vast stretches of time and space. </p>



<p>Water is essential for life as we know it, and its presence billions of years ago suggests that the elements needed for life have been around for a very long time.</p>



<p>Beyond that, water plays a key role in shaping how stars and galaxies evolve. When gas clouds cool, water helps by allowing those clouds to collapse more easily, leading to star birth. </p>



<p>By spotting it this far back, astronomers get new clues about how galaxies changed as the universe aged and matured.</p>



<h2 class="wp-block-heading" id="h-how-they-found-the-water-quasar">How they found the water quasar</h2>



<p>Bradford’s team began collecting data in 2008 with an instrument called Z-Spec at the California Institute of Technology’s Submillimeter Observatory (<a href="https://www.cso.caltech.edu/" target="_blank" rel="noreferrer noopener">CSO</a>). </p>



<p>This 33-foot telescope sits near the summit of Mauna Kea in Hawaii. They later confirmed their findings using the Combined Array for Research in Millimeter-Wave Astronomy (<a href="https://www.mmarray.org/" target="_blank" rel="noreferrer noopener">CARMA</a>), a set of radio dishes located high in the Inyo Mountains of Southern California.</p>



<p>Meanwhile, another group led by Dariusz Lis, senior research associate in physics at Caltech and deputy director of the Caltech Submillimeter Observatory, used the Plateau de Bure Interferometer in the French Alps. </p>



<p>In 2010, Lis’s team found hints of water in this quasar by detecting a single signature, while Bradford’s team uncovered multiple signals that revealed the massive amount of water present.</p>



<h2 class="wp-block-heading" id="h-where-do-we-go-from-here">Where do we go from here?</h2>



<p>To sum it all up, this discovery shows that even at a time when the universe was young, water formed and gathered in places we never would have guessed. </p>



<p>Instead of seeing just cold, empty darkness out there, astronomers have spotted a real treasure -- an enormous reservoir of water swirling around a quasar more than 12 billion light-years away. </p>



<p>This water vapor, along with the intense radiation from the black hole at the quasar’s center, paints a picture of an environment that is far denser, warmer, and more active than ordinary parts of the cosmos.</p>



<p>By studying this distant quasar, scientists can learn how the earliest galaxies came together and evolved. They can see how matter spread out, how black holes grew, and how even tiny molecules like water played a role in shaping the universe. </p>



<p>Every new detail uncovered by these long-ago signals traveling through time and space helps make sense of the vast cosmic story we are all a part of.</p>



<p>***</p>



<p>Other authors on the Bradford paper, "The water vapor spectrum of APM 08279+5255," include Hien Nguyen, Jamie Bock, Jonas Zmuidzinas and Bret Naylor of JPL; Alberto Bolatto of the University of Maryland, College Park; Phillip Maloney, Jason Glenn and Julia Kamenetzky of the University of Colorado, Boulder; James Aguirre, Roxana Lupu and Kimberly Scott of the University of Pennsylvania, Philadelphia; Hideo Matsuhara of the Institute of Space and Astronautical Science in Japan; and Eric Murphy of the Carnegie Institute of Science, Pasadena.<br><br>Funding for Z-Spec was provided by the <a href="https://www.nsf.gov" target="_blank" rel="noreferrer noopener">National Science Foundation</a>, <a href="https://www.nasa.gov" target="_blank" rel="noreferrer noopener">NASA</a>, the Research Corporation and the partner institutions.</p>



<p>The full study was published in the <em><a href="https://iopscience.iop.org/article/10.1088/2041-8205/738/1/L6/meta" target="_blank" rel="noreferrer noopener">Astrophysical Journal Letters</a></em>.</p>



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Enough water to fill trillions of Earth's oceans found in deep space circling a black hole

Astronomers have identified a remarkable water reservoir hidden in a...

<p>Cosmic rays are high-speed particles that move through space and crash into our atmosphere from every direction. These energetic particles, mostly atomic nuclei stripped of their electrons, have puzzled scientists for decades.</p>



<p>They hit Earth from different places with a wide range of energies. Some arrive at moderate levels, while others carry so much punch that researchers use special detectors stretching over vast areas to understand their true nature.</p>



<h2 class="wp-block-heading" id="h-cosmic-rays-above-5-eev">Cosmic rays above 5 EeV</h2>



<p>Particles carrying more than about five <a href="https://pwg.gsfc.nasa.gov/Education/wenpart1.html" target="_blank" rel="noreferrer noopener">exa-electronvolts</a> (EeV) of energy stand out because they mark a turning point. </p>



<p>At lower energies, cosmic rays often show a smoother distribution, and are strongly influenced by magnetic fields in our own galaxy.</p>



<p>Once they cross the 5 EeV threshold, however, their behavior and properties change. They begin to show patterns that cannot be explained by local sources alone. </p>



<p>Instead of originating mostly from within the Milky Way, they appear to come from distant corners of the cosmos that lie far beyond our familiar galactic neighborhood.</p>



<p>Studies indicate that at these energies, called <a href="https://arxiv.org/pdf/2412.05974" target="_blank" rel="noreferrer noopener">the ankle region</a>, the usual mixture of mostly light nuclei, like protons, gradually gives way to heavier particles that are less scrambled by <a href="https://ui.adsabs.harvard.edu/abs/2013pss5.book..641B/abstract" target="_blank" rel="noreferrer noopener">galactic magnetic fields</a>.</p>



<p>According to <a href="https://www.researchgate.net/profile/Jonathan-Biteau" target="_blank" rel="noreferrer noopener">Jonathan Biteau</a>, from the Academic Institute of France's <a href="https://www.auger.org/collaboration/" target="_blank" rel="noreferrer noopener">Pierre Auger Collaboration</a>, this energy range represents a step into a more revealing territory.</p>



<h2 class="wp-block-heading" id="h-observing-signs-in-the-data">Observing signs in the data</h2>



<p>Changes in the large-scale patterns of cosmic rays <a href="https://www.earth.com/news/cosmic-rays-help-archaeologists-determine-age-discoveries-prehistoric-settlements/" target="_blank" rel="noreferrer noopener">seen across the sky</a> start to stand out and offer clues to their sources. </p>



<p>This is where the cosmic ray story moves beyond a random spray of particles and hints at something else: extragalactic origins with distinct characteristics.</p>



<p>"Cosmic rays begin to reveal their secrets at energies above 5 EeV," said Biteau.</p>



<p>Measurements gathered over many years at facilities like the Pierre Auger Observatory show that once energies climb past this point, a pattern emerges in the shape of the energy spectrum.</p>



<p>Distinct features, known as the ankle near 5 EeV, the instep at about 15 EeV, and the toe around 45 EeV, mark noticeable shifts in the composition of the flux.</p>



<h2 class="wp-block-heading" id="h-clues-to-sources-of-cosmic-rays">Clues to sources of cosmic rays</h2>



<p>Observations <a href="https://arxiv.org/abs/2008.06486" target="_blank" rel="noreferrer noopener">indicate</a> that heavier nuclei start dominating the picture at higher energies. These changes tell researchers that different acceleration processes and astrophysical environments might be at play.</p>



<p>As energies increase, the sky coverage reveals that some directions supply more cosmic rays than others. This nonuniformity, known as anisotropy, has become more apparent.</p>



<p>Over the past decade, scientists have reported that the pattern of cosmic-ray arrival directions changes in a way that strongly suggests extragalactic sources. </p>



<p><a href="https://www.science.org/doi/10.1126/science.aan4338" target="_blank" rel="noreferrer noopener">Research</a> shows a large-scale anisotropy above a few EeV rising to a significance of about 7 σ above 8 EeV.</p>



<h2 class="wp-block-heading" id="h-one-step-closer">One step closer</h2>



<p>Pinpointing the birthplaces of these high-energy particles has proved challenging, but scientists continue to gather clues. </p>



<p>As cosmic rays push into these higher energy realms, they are less scattered by magnetic fields, making it easier to identify their original directions.</p>



<p>Emerging <a href="https://arxiv.org/abs/1612.07155" target="_blank" rel="noreferrer noopener">evidence</a> supports the idea that many of these ultra-high-energy rays are launched by extragalactic sources like star-forming galaxies or other intense astrophysical sites.</p>



<p>The data hint that active regions far beyond our galaxy could be connected to the observed arrival patterns.</p>



<p>Researchers also notice that certain sky regions, like those associated with clusters of nearby galaxies, line up better with the arrival directions than a purely uniform spread would allow.</p>



<h2 class="wp-block-heading" id="h-shifts-in-cosmic-rays-composition">Shifts in cosmic rays' composition</h2>



<p>Stepping above 5 EeV not only shines a light on extragalactic origins but also shows that the “stuff” hitting us at these energies is different.</p>



<p>Instead of mostly light nuclei like hydrogen and helium, many cosmic rays are heavier, involving atoms like carbon or oxygen.</p>



<p>This suggests that whatever "engines" are producing them, they must either selectively accelerate heavier particles or conditions in their environment alter the mix by the time they reach Earth.</p>



<p>The surprising scarcity of lighter elements runs counter to earlier guesses and requires fresh thinking from theorists.</p>



<h2 class="wp-block-heading" id="h-what-holds-the-key-to-their-birthplaces">What holds the key to their birthplaces?</h2>



<p>As these rays travel huge distances, their paths bend slightly in <a href="https://www.earth.com/news/powerful-magnetic-fields-may-be-key-features-of-black-holes/">magnetic fields</a> along the way. Even tiny bends can shuffle their directions enough to complicate efforts to pinpoint sources.</p>



<p>To address this, scientists model how nuclei of different masses respond to magnetic fields. If the rays still show a pattern that points to certain neighborhoods in space, that strengthens the argument that those regions contain the engines fueling these incredible energies.</p>



<h2 class="wp-block-heading" id="h-no-single-culprit-yet">No single culprit yet</h2>



<p>Many questions remain. Some experts suggest star-forming galaxies as prime suspects since these environments can host energetic events that might whip particles up to extreme energies.</p>



<p>Others consider whether active galactic nuclei, powered by <a href="https://astronomy.swin.edu.au/cosmos/S/Supermassive+Black+Hole" target="_blank" rel="noreferrer noopener">supermassive black holes</a>, might do the trick.</p>



<p>Current evidence favors the idea that star-forming galaxies provide a better match to the observed patterns than other candidates, but that does not slam the door on other possibilities.</p>



<h2 class="wp-block-heading" id="h-bridging-theory-and-observations">Bridging theory and observations</h2>



<p>The unusual composition and the changing patterns seen above 5 EeV push theorists to re-examine old ideas. </p>



<p>Traditional models that relied on smooth distributions of particle energies and the presence of light nuclei are under pressure.</p>



<p>New models must explain the sharp transitions, the heavy nuclei, and the hints of extragalactic origins. As measurements improve, scientists hope to confirm or refute certain types of sources. </p>



<p>If future data link cosmic rays more closely to certain types of galaxies or astrophysical conditions, it would be a major step forward in understanding how the universe’s most energetic particles are made.</p>



<h2 class="wp-block-heading" id="h-ongoing-upgrades-and-the-future">Ongoing upgrades and the future</h2>



<p>As detectors improve and more data are collected, the community expects to refine the energy calibration, measure more showers, and achieve better accuracy. Each improvement adds detail to this cosmic jigsaw puzzle.</p>



<p>If a tighter correlation with certain galaxy groups emerges, that could finally close in on the actual sources. Until then, each new measurement, each new analysis, and each new insight keeps the hunt alive.</p>



<p>The research paper was published in the <em><a href="https://journals.aps.org/prd/abstract/10.1103/PhysRevD.102.062005" target="_blank" rel="noreferrer noopener">Physical Review Journals</a></em>.</p>



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Strange, high-energy cosmic rays: Did something outside our galaxy send them here?

Cosmic rays are high-speed particles that move through space and...


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<p>Today’s <strong>Video of the Day</strong> from the <a href="https://www.esa.int/">European Space Agency</a> features part of the Glacier Bay National Park and Preserve on the coast of southeast Alaska. This region has a diverse group of animals, such as humpback whales, orcas, sea otters, bears, moose, wolves and mountain goats. The landscape of Glacier Bay includes rugged mountains, freshwater lakes, glaciers and deep fjords.</p>



<p>&#8220;The bay contains some of the world’s most impressive glaciers that descend from the ice-covered St. Elias Range in the east and the Fairweather Range in the west, with a few notable tidewater glaciers extending all the way to the sea,&#8221; reports NASA.</p>



<p>&#8220;Glacier Bay is just one of the many areas suffering from the effects of global warming. The bay is expected to become warmer and drier over the next century, with widespread effects including the further shrinking glaciers, reduced sea ice and shoreline erosion.&#8221;</p>



<p>The remoteness of the area makes it challenging to monitor, but satellite images provide an opportunity for scientists to observe and study Glacier Bay with great detail. In 2021, experts with ESA’s CryoSat mission used radar altimeter data to determine how much ice has been lost from mountain glaciers in the region.&nbsp;</p>



<p><em>Video/ Image Credit: ESA</em></p>



<p><em>&#8211;</em><em>&#8212;</em></p>



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


Glacier Bay National Park in southeast Alaska