Today's Image of the Day from the European Space Agency features a compilation of European cities that resemble stars. 



“Star-shaped cities are scattered across Europe, their geometric designs most appreciated when viewed from above,” noted <a href="https://www.esa.int/ESA_Multimedia/Images/2024/12/Earth_from_Space_Star_cities" target="_blank" rel="noreferrer noopener">ESA</a>. 



<h2 class="wp-block-heading" id="h-development-of-star-shaped-cities">Development of star-shaped cities</h2>



The development of star-shaped fortresses, also known as bastion forts, emerged during the Renaissance in Italy as a response to the rapidly evolving art of <a href="https://www.earth.com/news/migrating-eagles-have-been-rerouted-by-the-war-in-ukraine/" target="_blank" rel="noreferrer noopener">warfare</a>.&nbsp;



Traditional medieval fortifications, characterized by high, straight walls and square towers, became vulnerable with the advent of gunpowder weaponry. Cannons could easily reduce these structures to rubble, rendering them obsolete.



The star-shaped design addressed these vulnerabilities by incorporating wide moats and projecting bastions - angled structures that jutted outward from the main walls.&nbsp;



These bastions provided overlapping fields of fire, allowing defenders to cover blind spots and effectively repel attackers attempting to approach or scale the walls.&nbsp;



Additionally, the sloped walls of these fortresses, known as glacis, were designed to deflect cannonballs rather than absorb their impact, further enhancing their resilience.



This innovative design not only improved defensive capabilities but also transformed the battlefield, forcing attackers to develop new siege techniques. It marked a pivotal moment in military engineering, influencing fortress construction across Europe and beyond for centuries.



<h2 class="wp-block-heading" id="h-examples-of-star-shaped-cities">Examples of star-shaped cities</h2>



“Four examples of such cities can be seen here, arranged clockwise from the top left: Bourtange in the Netherlands, Palmanova in Italy, Almeida in Portugal, and Neuf-Brisach in France,” said ESA.



“The green and red hues evoke a Christmas vibe, achieved through different band combinations during image processing to generate true-color (green) and false-color (red) visuals.”



<h3 class="wp-block-heading" id="h-bourtange-netherlands">Bourtange, Netherlands </h3>



Fort Bourtange, nestled in the picturesque countryside of northeast Netherlands near the German border, is a remarkable example of Renaissance military architecture and urban planning.&nbsp;



Constructed in 1593 during the Eighty Years' War, it was strategically positioned to control the only road linking Germany to the Dutch city of Groningen - a vital route for military and trade purposes.&nbsp;



Its unique pentagonal, star-shaped design featured angled bastions, wide moats, and interconnected defensive structures, making it nearly impenetrable to enemy forces equipped with the era's artillery.



In 1851, after centuries of military service, Fort Bourtange was decommissioned and transformed into a peaceful village.&nbsp;



Despite the change in purpose, its original geometric layout, defined by precise angles and symmetrical patterns, remained intact. The pentagonal walls, surrounding waterways, and radial street design continue to showcase the ingenuity of its designers.



<h3 class="wp-block-heading" id="h-palmanova-italy">Palmanova, Italy </h3>



Palmanova, located in the Friuli-Venezia Giulia region of northeast Italy, is a masterpiece of Renaissance urban and military planning.&nbsp;



Designated as a UNESCO World Heritage site, it exemplifies the idealized city envisioned during the late Renaissance, combining beauty, functionality, and <a href="https://www.earth.com/news/preparing-u-s-military-bases-for-sea-level-rise/" target="_blank" rel="noreferrer noopener">military</a> innovation.&nbsp;



Constructed in 1593 by the Republic of Venice, Palmanova was strategically designed to protect the Republic’s northeastern borders from external threats - particularly the Ottoman Empire.



The city’s layout embodies the principles of symmetry and order characteristic of the Renaissance. Its unique radial design spreads out from the central hexagonal square, known as Piazza Grande or Piazza del Duomo, which serves as the civic and social heart of the city.&nbsp;



From this central hub, six straight avenues fan outward, connecting the square to the surrounding neighborhoods and gates. This design was not only aesthetically pleasing but also practical, allowing for efficient movement and communication within the city.



Today, Palmanova is celebrated not only for its historical and architectural significance but also as a rare example of a perfectly preserved star fortress.&nbsp;



<h3 class="wp-block-heading" id="h-almeida-portugal-nbsp">Almeida, Portugal&nbsp;</h3>



Perched on a high plain in northeast Portugal near the Spanish border, the fortress of Almeida is a striking example of military engineering and a symbol of Portugal’s resilience.&nbsp;



Built to secure the nation’s eastern frontier, Almeida has played a significant role in Portuguese history, particularly during its early years of independence and throughout various military conflicts, including the Peninsular War.



The fortress's defining star-shaped ramparts consist of twelve points, each projecting outward to eliminate blind spots and provide overlapping fields of fire against advancing enemies.&nbsp;



The thick walls, surrounding moats, and angular bastions made Almeida a formidable stronghold capable of withstanding prolonged sieges.



<h3 class="wp-block-heading" id="h-neuf-brisach-france">Neuf-Brisach, France</h3>



Neuf-Brisach, located in the Alsace region of northeastern <a href="https://www.earth.com/news/470-million-year-old-animal-fossils-discovered-in-frances-cabrieres-biota/" target="_blank" rel="noreferrer noopener">France</a> near the German border, is another fascinating example of military and urban design.&nbsp;



The town was constructed in 1697 after the loss of Breisach, which stood on the opposite bank of the Rhine River in Germany.&nbsp;



The name "Neuf" (meaning "new" in French) reflects its creation as a strategic replacement and fortification to strengthen France's defense along its eastern border.



Designed by Sébastien Le Prestre de Vauban, the renowned military engineer under King Louis XIV, Neuf-Brisach is part of the extensive network of fortifications that Vauban designed to protect France from external threats.&nbsp;



Vauban's expertise in defensive architecture is evident in the town's star-shaped layout, which was intended to optimize defense while accommodating civilian life within the fortifications.&nbsp;



The fortifications were built to withstand sieges and were strategically positioned to control movement across the Rhine River and defend against potential invasions. The outer star-shaped ramparts extend in a way that creates a nearly impenetrable defensive perimeter.



Image Credit: European Space Agency&nbsp;



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Star-shaped cities scattered across Europe

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

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



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.



"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>.



"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."



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



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>.



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.



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



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.



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.



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



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



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. 



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.



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



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



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.



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."



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.



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.



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. 



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



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



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.



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



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



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.



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. 



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.



Image Credit: ESA



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

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.



“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.



Image Credit: NASA Earth Observatory



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Retreating glaciers and expanding meltwater lakes in Alaska

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

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. 



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



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



“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.”



“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;



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.”



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



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;



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.



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;



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.



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



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;



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.



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. 



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



“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.



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;



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;



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.



Image Credit: NASA Earth Observatory&nbsp;



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Mountain peaks and plains of central Mongolia 

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. 



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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Spiral galaxy NGC 1559 is a loner in outer space

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



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



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



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



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



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



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



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



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



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.



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



<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. 



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.



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



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.



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>.



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



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



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



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



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



Studying 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. 



Image Credit: ESA/Hubble &amp; NASA



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Luminous galaxy NGC 3783 and a blue giant star

The distinguishing marks of these African birds are a bright green crown with a lilac color on the throat that deepens as it descends onto the chest. Some lilac breasted rollers have bright blue throats with lilac patches on their abdomens.

Lilac Breasted Roller

Santa,Claus,Sitting,Near,The,Fireplace,And,Christmas,Tree,With

Every December, colorful lights and festive tunes remind kids, and adults, that Santa Claus is on his way. Families fill their homes with decorations, children write wish lists, and a sense of anticipation hangs in the air. 



Parents have long told their kids that if they behave well, Santa will bring them just what they asked for. Until recently, few studies examined whether this belief actually influenced how kids act.



In a new project, researchers decided to see if <a href="https://www.earth.com/news/irregular-bedtimes-disrupt-the-well-being-and-behavior-of-children/" target="_blank" rel="noreferrer noopener">children</a> truly become more considerate when they think Santa is watching. 



They explored whether kids act better because of the story of Santa or because of everything else going on during the holiday season. 



Professor Kapitány from the <a href="https://www.ox.ac.uk/" target="_blank" rel="noreferrer noopener">University of Oxford</a> led the investigation along with colleagues from <a href="https://www.durham.ac.uk/" target="_blank" rel="noreferrer noopener">Durham</a>, <a href="https://www.ed.ac.uk/" target="_blank" rel="noreferrer noopener">Edinburgh</a>, and <a href="https://www.leeds.ac.uk/" target="_blank" rel="noreferrer noopener">Leeds</a>.



<h2 class="wp-block-heading" id="h-kids-santa-and-surprises">Kids, Santa, and surprises</h2>



The study tracked 533 kids between ages four and nine over three separate Christmases and visits from Santa. Families <a href="https://www.earth.com/news/kids-with-behavioral-issues-have-high-cortisol-levels-in-their-hair/" target="_blank" rel="noreferrer noopener">reported on behaviors</a> like sharing, helping others, and following rules. 



Parents also described whether their kids believed in Santa and took part in festive traditions. According to the data, there was no direct link between Santa belief alone and an increase in kindness.



Instead, good behavior rose as Christmas neared when families engaged in activities such as decorating their homes, singing carols, and enjoying special treats.&nbsp;



The study noted that these experiences led to small but consistent boosts in generous and <a href="https://www.earth.com/news/kindergarten-conduct-childhood-behavioral-problems-will-cost-society-later/" target="_blank" rel="noreferrer noopener">respectful actions</a>. 



This shift also came with a bump in more rowdy moments, highlighting that heightened excitement can show up in many ways.



<h2 class="wp-block-heading" id="h-the-power-of-festive-rituals">The power of festive rituals</h2>



For many families, hanging ornaments or baking Christmas cookies is more than just a fun holiday pastime. 



These rituals offer children a chance to feel a sense of togetherness and excitement that breaks up their usual routine. 



The study suggests that these shared activities have a greater <a href="https://www.earth.com/news/children-consider-their-own-past-actions-before-judging-others/" target="_blank" rel="noreferrer noopener">effect on kindness</a> than the idea of being judged by a mysterious gift-giver in a red suit.



Parents often say they remind kids to be on their best behavior so Santa will reward them. Yet the findings show it’s the holiday atmosphere itself that has the strongest pull. 



One researcher described it by saying “the magic is in the time of year, so to speak, not in the claim over the supernatural big man.”



<h2 class="wp-block-heading" id="h-supernatural-beliefs-and-morality">Supernatural beliefs and morality</h2>



Some scholars point out that Santa is often placed on the same pedestal as other powerful beings in certain cultures. 



Parents treat him as a figure who can watch children from afar, keep track of good deeds, and decide on gifts. 



This study adds to conversations about how belief in unseen forces might shape moral choices.



Other work shows that religious ideas can sometimes bring out prosocial behavior. Hearing about rules or promises of rewards can prompt more cooperation.&nbsp;



In the case of Santa, though, the results suggest that the presence of traditions might play a bigger role in guiding kids toward friendly, generous actions.



<h2 class="wp-block-heading" id="h-contrasting-philosophies-on-kids-and-santa">Contrasting philosophies on kids and Santa</h2>



Philosophers have different views on whether parents should even promote Santa’s story. 



Dr. Joseph Millum from the <a href="https://www.st-andrews.ac.uk/" target="_blank" rel="noreferrer noopener">University of St. Andrews</a> worries it “breaches trust,” calling Santa a “preposterous lie.” Others feel that Santa can be a healthy way to bring joy into children’s lives. 



Tom Whyman, a lecturer in philosophy at the <a href="https://www.liverpool.ac.uk/" target="_blank" rel="noreferrer noopener">University of Liverpool</a>, says that “kids need Santa.” 



These opinions highlight the varying attitudes people have toward a figure whose influence has become an enduring feature of holiday culture.



When parents choose whether to encourage this tale, they grapple with how it shapes their children’s sense of wonder and truth. 



Some families see Santa as <a href="https://www.earth.com/news/pretend-play-builds-the-foundation-for-learning-and-relationships/" target="_blank" rel="noreferrer noopener">harmless make-believe</a>, while others wonder if creating a magical visitor might later undermine a child’s trust. 



The study reminds us that cultural myths carry weight, yet they may not fully explain shifts in children’s behavior.



<h2 class="wp-block-heading" id="h-implications-for-holiday-traditions">Implications for holiday traditions</h2>



The research shows that singing festive songs, <a href="https://www.earth.com/news/christmas-trees-have-unique-strategies-to-survive-freezing-winters/" target="_blank" rel="noreferrer noopener">placing ornaments on a tree</a>, or preparing traditional foods creates a distinct environment. That environment is linked with both extra kindness and occasional bursts of negative behavior. 



While the belief in Santa himself did not correlate directly with improved conduct, the coordinated celebration of the season proved to be more powerful.



Families can consider how these moments <a href="https://www.earth.com/news/personality-traits-are-not-strongly-inherited-from-parents/" target="_blank" rel="noreferrer noopener">bring the household closer</a>. Children who help bake cookies or watch a classic Christmas movie often feel a greater sense of involvement. 



This sense of participation aligns with the study’s findings that holiday events can be a driving force behind thoughtful gestures, cooperation, and cheer.



<h2 class="wp-block-heading" id="h-bigger-questions-about-childhood-and-culture">Bigger questions about childhood and culture</h2>



Santa’s modern image traces back to a blend of folklore, marketing campaigns, and traditions inspired by Saint Nicholas. 



For countless children, the idea of a kindhearted figure traveling the skies in a single night is a highlight of December. 



This study encourages us to think about how such stories fit into broader questions about parenting approaches and cultural myths. 



Many communities celebrate special figures who reward the nice and ignore or punish the naughty. 



In each case, children experience stories they can hold onto, if only for a few magical years. The current research suggests that these stories may matter less than the rituals and music, but they still add color to the season.



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



Plenty of families continue to share the Santa story, watch Christmas movies, and maintain lively traditions. 



The researchers point out that more studies could explore how different cultural celebrations, and the potential <a href="https://www.earth.com/news/holiday-stress-is-higher-this-year-compared-to-2023/" target="_blank" rel="noreferrer noopener">stress levels surrounding them</a>, ultimately help shape child development. 



From the outside, it might seem obvious that gatherings, songs, and decorations encourage bright and kind behavior, yet measuring these elements takes careful planning.



Some psychologists are curious about whether similar patterns show up around other holidays or special events with strong rituals.&nbsp;



The core message remains that communal practices, family bonding, and joyful anticipation often spark gentler and more considerate behavior in children. 



The Santa myth is part of that puzzle, but it may not be the only factor making kids play nicely.



<h2 class="wp-block-heading" id="h-what-did-we-learn-about-kids-and-santa">What did we learn about kids and Santa?</h2>



The takeaway here is that Christmas is a powerful backdrop for <a href="https://www.earth.com/news/many-parents-use-threats-to-discipline-children-but-its-not-effective-in-the-long-run/" target="_blank" rel="noreferrer noopener">shaping how children behave</a>. 



A lively household filled with festive foods, carols, and colorful decorations can steer kids toward more thoughtful choices, even if the well-known Santa story doesn’t stand alone as a motivator. 



Traditions that families share appear to matter more than the promise of presents under the tree.



These observations offer a new way to think about how myths and rituals come together to create a meaningful holiday experience.&nbsp;



Children may still look forward to Santa’s arrival each year, but the real spark for positive behavior lies in those precious moments spent enjoying the season.



The full study was published in the journal <a href="https://osf.io/preprints/osf/e8jm6" target="_blank" rel="noreferrer noopener">OSF Pre-prints</a>.



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Does believing in Santa really make kids behave better? A new study found out

Every December, colorful lights and festive tunes remind kids, and...

NASA’s Parker Solar Probe touched the Sun's atmosphere, flying within 3.8 million miles (around 6.1 million kilometers) from the surface of the Sun on Tuesday, Dec. 24, at 6:53 a.m. EST. 



During its closest approach, also called perihelion, mission operations will be out of contact with the spacecraft. 



Parker will transmit another beacon tone on Friday, Dec. 27, to confirm its health following the close flyby.



<h2 class="wp-block-heading" id="h-going-where-no-human-made-object-has-gone">Going where no human-made object has gone</h2>



This approach is unlike anything previously accomplished by a human-made spacecraft, marking a landmark in solar science that may rewrite much of what we know about our star.



Arik Posner, <a href="https://parkersolarprobe.jhuapl.edu/" target="_blank" rel="noreferrer noopener">Parker Solar Probe</a> program scientist at NASA Headquarters in Washington, sees this effort as a new window into solar research. “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,” said <a href="https://science.nasa.gov/people/dr-arik-posner/" target="_blank" rel="noreferrer noopener">Arik</a>. The Johns Hopkins Applied Physics Laboratory (<a href="https://www.jhuapl.edu/" target="_blank" rel="noreferrer noopener">APL</a>) in Laurel, Maryland, manages mission operations and is keeping a watchful eye on every step as Parker speeds by.



<h2 class="wp-block-heading" id="h-breathtaking-pace-of-the-parker-solar-probe">Breathtaking pace of the Parker solar probe</h2>



The spacecraft is moving at approximately <a href="https://www.nasa.gov/feature/goddard/parker-solar-probe" target="_blank" rel="noreferrer noopener">430,000 miles per hour</a>. At that velocity, Parker could zip from New York to Los Angeles in about 20 seconds. 



By <a href="https://www.earth.com/news/parker-solar-probe-will-fly-through-suns-atmosphere-tomorrow-for-the-first-time/" target="_blank" rel="noreferrer noopener">approaching the Sun</a> so closely, mission teams hope to retrieve data that no earlier craft could access. Particles in the corona -- where temperatures can exceed a few million degrees -- tend to behave in puzzling ways. 



Scientists aim to see how these intense conditions might shape <a href="https://science.nasa.gov/sun/what-is-the-solar-wind/" target="_blank" rel="noreferrer noopener">solar wind</a>, which jets out at more than one million miles per hour.



Engineers designed Parker’s trajectory with careful flybys of Venus to shrink its orbit gradually around the Sun. This path has taken years to perfect since launch in 2018. 



Each loop demanded detailed calculations to ensure the craft can survive the approach, collect the right measurements, and keep sending updates back to Earth.



<h2 class="wp-block-heading" id="h-solar-probe-battling-extreme-heat">Solar probe battling extreme heat</h2>



Because the Sun’s heat is punishing at such a short distance, Parker Solar Probe relies on a <a href="https://parkersolarprobe.jhuapl.edu/Spacecraft/index.php#Extreme-Environments" target="_blank" rel="noreferrer noopener">carbon-composite shield</a> 4.5 inches thick.



This protective layer keeps sensitive instruments near room temperature while the shield’s front side can face extreme temperatures above 2,500 degrees Fahrenheit.



Sophisticated cooling systems also channel heat away from the core of the <a href="https://www.earth.com/news/meet-the-fastest-human-made-object-ever-nasas-parker-solar-probe/" target="_blank" rel="noreferrer noopener">spacecraft</a>, helping to sustain the electronics that record measurements of plasma, magnetic fields, and solar wind particles.



Inside, the instruments are scanning for clues to explain the corona’s unusual temperatures, which skyrocket to levels far higher than the Sun’s visible surface. 



Those same instruments are also watching for charged particle bursts and fluctuations in magnetic fields that might help answer big questions about what accelerates the solar wind.



<h2 class="wp-block-heading" id="h-crucial-timing-and-limited-contact">Crucial timing and limited contact</h2>



Today’s perihelion means Parker is currently skimming the outer atmosphere of the <a href="https://www.earth.com/news/solar-orbiter-spacecraft-sees-the-sun-through-three-different-lenses/" target="_blank" rel="noreferrer noopener">Sun</a> while in autonomous mode, out of immediate radio contact.



This window of silence is standard because powerful solar emissions prevent reliable communication. Mission operators anticipate a beacon tone on December 27, which should confirm Parker has survived.



Scientists believe that data from this flyby could provide <a href="https://www.earth.com/news/parker-solar-probe-will-fly-through-suns-atmosphere-tomorrow-for-the-first-time/" target="_blank" rel="noreferrer noopener">unprecedented detail on solar activity</a>. Periods of heightened activity, known as solar maxima, produce more flares and coronal mass ejections. These events can spawn auroras at unexpected latitudes and threaten satellites with bursts of charged particles. 



By collecting data from close range, Parker might reveal new insights into how these explosive happenings form and evolve.



<h2 class="wp-block-heading" id="h-visionary-behind-the-parker-solar-probe">Visionary behind the Parker solar probe</h2>



This trailblazer of solar research is named after <a href="https://news.uchicago.edu/story/eugene-parker-legendary-figure-solar-science-and-namesake-parker-solar-probe-1927-2022" target="_blank" rel="noreferrer noopener">Dr. Eugene N. Parker</a>, the late astrophysicist from the University of Chicago who proposed the existence of the solar wind back in the 1950s.



He changed our understanding of how stars interact with their surroundings. In 2018, he became the first person to witness the launch of a spacecraft bearing his name. 



Though he passed away in 2022, his legacy lives on in every close pass the probe completes.



<h2 class="wp-block-heading" id="h-a-closer-look-at-solar-wind">A closer look at solar wind</h2>



One of the main motivations behind Parker Solar Probe mission is to figure out how <a href="https://www.earth.com/news/strong-solar-storm-warning-issued-as-two-cmes-will-hit-earth-tomorrow/" target="_blank" rel="noreferrer noopener">solar wind</a>, that stream of charged particles racing from the Sun, accelerates to incredible speeds. Scientists hope Parker will pinpoint where and how energy is transferred to these particles. Such information could refine space weather forecasts, which are critical for protecting satellites, power grids, and astronauts in orbit.



<a href="https://www.plasmacoalition.org/plasma_writeups/solar_plasmas.pdf" target="_blank" rel="noreferrer noopener">Plasma</a> behavior at these altitudes can also inform theories about stellar physics beyond the Sun. 



Many stars release similar particle streams, so unraveling the inner workings of the solar wind could offer a template for understanding events happening light-years away.



<h2 class="wp-block-heading" id="h-high-stakes-data-for-space-weather-predictions">High-stakes data for space weather predictions</h2>



Operators know that space weather can have major effects here on Earth. Sudden geomagnetic storms have been known to disrupt radio signals, damage satellites, and even cause power outages. By studying the Sun’s activity from the inside, Parker could lead to more accurate warnings for regions of the world vulnerable to blackouts. 



Air traffic, GPS services, and communication infrastructure may all benefit from improved predictions of <a href="https://science.nasa.gov/science-research/heliophysics/space-weather/solar-flares/what-is-a-solar-flare/" target="_blank" rel="noreferrer noopener">solar flares</a> and <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">particle storms</a>.



<h2 class="wp-block-heading" id="h-a-milestone-for-parker-solar-probe">A milestone for Parker Solar Probe</h2>



Now that the probe is at perihelion, mission managers will hold their breath for a few days.



“No human-made object has ever passed this close to a star, so Parker will truly be returning data from uncharted territory,” 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 at <a href="https://www.jhuapl.edu/" target="_blank" rel="noreferrer noopener">APL</a>. 



He added that the team is eager to see how Parker managed the flyby when the link reopens.



This moment is a milestone for solar science. If everything goes as planned, Parker will maintain its orbit for future close passes, each offering a renewed chance to investigate the corona’s strange properties.



Researchers anticipate more discoveries that will fill in knowledge gaps about the Sun’s extreme environment.



Far from being an isolated phenomenon, the Sun’s behavior plays a significant role in shaping conditions on Earth. 



Today’s brush with solar fury signals the continuing progress of human exploration -- and the promise of deeper insight into the star that illuminates our world.



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Mission accomplished? Solar Probe just touched the Sun, but we don't know if it survived

NASA’s Parker Solar Probe touched the Sun's atmosphere, flying within...

The solar system, billions of years old, holds many secrets about its formation. Among its fascinating residents is Chiron, a centaur orbiting between Jupiter and Neptune. 



New findings by scientists using the James Webb Space Telescope (JWST) shed light on this hybrid of comet and asteroid, revealing unprecedented insights into its surface chemistry and activity.



The study was led by Dr. Noemí Pinilla-Alonso of the University of Oviedo and Dr. Charles Schambeau from the University of Central Florida (UCF). Their findings could reshape our understanding of centaurs and the solar system’s early history.



<h2 class="wp-block-heading" id="h-time-capsules-of-the-solar-system">Time capsules of the solar system </h2>



<a href="https://www.earth.com/news/deep-space-objects-called-centaurs-29p-continue-to-perplex-nasa/" target="_blank" rel="noreferrer noopener">Centaurs</a> are objects with dual characteristics, straddling the line between asteroids and comets. 



Chiron, discovered in 1977, is unique even among centaurs. It exhibits comet-like behavior, including a coma - a cloud of gas and dust - alongside distinct surface and interior features.



Dr. Pinilla-Alonso emphasizes that centaurs act as “time capsules,” preserving information about the solar system’s formation. "All small bodies in the solar system talk to us about how it was back in time,” she explained. 



Chiron’s activity, driven by solar heating, offers a rare opportunity to explore these preserved secrets.



<h2 class="wp-block-heading" id="h-unprecedented-chemical-diversity-in-a-centaur">Unprecedented chemical diversity in a centaur</h2>



Using <a href="https://science.nasa.gov/mission/webb/" target="_blank" rel="noreferrer noopener">JWST</a>, the team discovered that Chiron's surface hosts carbon dioxide and carbon monoxide ice. Its coma contains methane and other gases, marking the first detection of such diversity in a centaur. 



“These results are like nothing we’ve seen before,” noted Dr. Schambeau from <a href="https://www.ucf.edu/" target="_blank" rel="noreferrer noopener">UCF</a>.



JWST’s advanced capabilities allowed the researchers to study Chiron even at its farthest point from the Sun. This distance usually limits the activity of similar objects, such as trans-Neptunian objects (TNOs).



Unlike <a href="https://www.earth.com/news/comet-will-be-visible-for-the-first-time-in-50000-years/" target="_blank" rel="noreferrer noopener">comets</a> closer to the Sun, Chiron’s thinner coma offers clearer insights into its surface chemistry.



<h2 class="wp-block-heading" id="h-chiron-s-ice-and-gas-dynamics">Chiron's ice and gas dynamics</h2>



Dr. Pinilla-Alonso noted that Chiron’s dual nature makes it invaluable for studying processes in both comets and <a href="https://www.earth.com/news/two-large-asteroids-will-pass-near-earth-this-week/" target="_blank" rel="noreferrer noopener">asteroids</a>. 



"What is unique about Chiron is that we can observe both the surface and the coma,” she said.



This dual observation provides critical information about the ice layer's thickness, porosity, and chemical properties.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/2060-Chiron_coma_asteroid-comet-hybrid_credit-USF_1m.jpg"><img src="https://www.earth.com/wp-content/uploads/2024/12/2060-Chiron_coma_asteroid-comet-hybrid_credit-USF_1s.webp" alt="Artist's impression of 2060 Chiron, an active centaur, surrounded by a faint disc of debris. Bright icy deposits and active areas are visible on its surface. Credtis: William D. González Sierra of the Florida Space Institute, University of Central Florida." class="wp-image-1954508"/></a><figcaption class="wp-element-caption">Artist's impression of 2060 Chiron, an active centaur, surrounded by a faint disc of debris. Bright icy deposits and active areas are visible on its surface. Credtis: William D. González Sierra of the Florida Space Institute, University of Central Florida.</figcaption></figure>



JWST’s observations revealed the coexistence of primordial ices, such as methane and water, and newer compounds formed through surface processes. 



“Every active centaur we observe shows some peculiarity,” said Dr. Pinilla-Alonso. Understanding these peculiarities may uncover patterns across these <a href="https://www.earth.com/news/once-in-a-lifetime-comet-will-be-easily-visible-this-month/" target="_blank" rel="noreferrer noopener">enigmatic objects</a>.



<h2 class="wp-block-heading" id="h-an-oddball-among-centaurs">An oddball among centaurs</h2>



Chiron stands out due to its unusual behavior, including comet-like activity and potential rings of debris. 



Dr. Schambeau describes it as “an oddball” with a unique thermophysical process. He analyzed methane in Chiron’s coma, linking its outflow to sun-heated regions on its surface.



These findings deepen our understanding of <a href="https://www.earth.com/wp-content/uploads/2024/12/2060-chiron_debris-disk_asteroid-comet-hybrid_credit-USF_1big.jpg" target="_blank" rel="noreferrer noopener">centaurs’ evolution and behavior</a>. 



Chiron’s dynamic environment provides clues about how solar heating influences its surface and subsurface, offering a glimpse into processes shaping similar bodies.



<h2 class="wp-block-heading" id="h-origins-and-future-of-chiron">Origins and future of Chiron</h2>



Chiron likely originated in the TNO region before moving into its current orbit. Gravitational interactions with giant planets alter the paths of centaurs, exposing them to varied environments.



Dr. Pinilla-Alonso explained that centaurs typically remain in the giant planets’ region for about a million years before being ejected. “They may end their lives as Jupiter Family comets or return to the TNOs region."



Chiron’s journey across the solar system exposes it to solar radiation, driving surface changes and creating its unique chemical composition. 



Understanding this evolution provides valuable insights into the early solar system.



<h2 class="wp-block-heading" id="h-broader-implications-of-chiron-s-discovery">Broader implications of Chiron’s discovery</h2>



The study’s implications extend beyond Chiron. Identifying gases and ices on distant objects enhances our understanding of the solar system’s building blocks. 



These findings could also inform future research on centaurs and other icy bodies.



Dr. Pinilla-Alonso noted that JWST’s spectra revealed intricate details about Chiron’s ices and their interactions. "Based on our new JWST data, I’m not so sure we have a standard centaur."



Further studies may uncover shared traits among centaurs, offering a clearer picture of their origins and diversity.



<h2 class="wp-block-heading" id="h-learning-more-about-centaurs">Learning more about centaurs</h2>



The researchers from <a href="https://www.uniovi.es" target="_blank" rel="noreferrer noopener">University of Oviedo</a> and UCF plan to continue observing Chiron as it approaches the Sun.



Closer proximity will enable more detailed studies of its surface and coma, potentially uncovering new chemical and physical properties.



Future research may also explore seasonal variations and illumination effects on Chiron’s ice reservoir. Such studies could refine our understanding of how centaurs interact with their environments and evolve over time.



<h2 class="wp-block-heading" id="h-unveiling-the-mysteries-of-the-solar-system">Unveiling the mysteries of the solar system</h2>



The JWST, an international collaboration led by NASA, has revolutionized space science. 



Its ability to observe distant objects like Chiron is solving long-standing mysteries about the solar system and beyond. These discoveries highlight the telescope’s transformative impact on planetary science.



“JWST has made these detections accessible. These results enhance our understanding of Chiron’s interior composition and its unique behaviors,” concluded Dr. Schambeau.



<h2 class="wp-block-heading" id="h-new-chapter-in-solar-system-exploration">New chapter in solar system exploration</h2>



Chiron’s unique chemistry and activity mark a significant milestone in understanding the solar system’s origins. 



The ongoing research, powered by JWST’s capabilities, promises to unravel more secrets about this enigmatic centaur and its <a href="https://www.earth.com/news/its-official-earth-now-has-two-moons-captured-asteroid-2024-pt5/" target="_blank" rel="noreferrer noopener">counterparts</a>.



Through Chiron, scientists are not just uncovering the past - they are laying the groundwork for future exploration of icy bodies across the solar system.



“The analysis of Chiron’s gases and ices opens new frontiers and opportunities for exciting research,” said Dr. Pinilla-Alonso.



The study is published in the journal <a href="https://www.aanda.org/articles/aa/full_html/2024/12/aa50124-24/aa50124-24.html" target="_blank" rel="noreferrer noopener">Astronomy &amp; Astrophysics</a>.



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Asteroid-comet hybrid named "Chiron" is unlike anything ever seen before

The solar system, billions of years old, holds many secrets...

Looks,Like,Reversed,Infinity,Time,Spiral,,Digital,Generated,Image,With

It is widely known among scientists that light sometimes appears to exit a material before it has even entered. This odd "negative time" phenomenon was long seen as an illusion caused by the way waves become distorted by matter. 



Over time, many considered it a harmless quirk of physics, dismissed without much further investigation. Now, fresh experiments suggest that this behavior might carry deeper implications related to "negative time."



Researchers recently posted findings on the preprint server arXiv, drawing global interest and some reservations about what it all means.



<h2 class="wp-block-heading" id="h-negative-time-is-no-longer-theoretical">"Negative time" is no longer theoretical</h2>



Aephraim Steinberg, a <a href="https://www.utoronto.ca/" target="_blank" rel="noreferrer noopener">University of Toronto</a> professor in experimental quantum physics, has seen how people can misunderstand discussions about negative time.



"This is tough stuff, even for us to talk about with other physicists. We get misunderstood all the time," he said. His team contends that negative time is not just theoretical but may exist in a measurable way.



They remain cautious in describing their experiments, emphasizing that the results reflect a subtle effect in <a href="https://www.earth.com/news/quantum-entanglement-a-simple-way-to-grasp-this-impossible-concept-carl-kocher/" target="_blank" rel="noreferrer noopener">quantum mechanics</a>. 



"That time turned out to be negative," Steinberg explained. Their data points to strange interactions between light and matter that defy everyday assumptions.



<h2 class="wp-block-heading" id="h-quantum-quirks">Quantum quirks</h2>



Their basement lab brims with mirrors, wires, and delicate lasers that track how photons interact with atoms. 



The atoms sometimes <a href="https://www.earth.com/news/precise-shape-of-single-photon-light-revealed-for-the-first-time/" target="_blank" rel="noreferrer noopener">absorb photons</a> and later emit them, leaving the atoms in an excited state for a short period. Measuring this period was tricky, and to many, it sounded like it might flirt with impossibilities.



Steinberg and graduate student Daniela Angulo focused on the short time atoms remain excited. By collecting data on how <a href="https://www.earth.com/news/super-photons-fascinating-behavior-in-quantum-realm/" target="_blank" rel="noreferrer noopener">atoms emit absorbed light</a>, they uncovered intervals that appeared less than zero. 



"We don't want to say anything traveled backward in time," Steinberg said. "That's a misinterpretation."



<h2 class="wp-block-heading" id="h-negative-time-doesn-t-violate-reality">"Negative time" doesn't violate reality</h2>



Investigations into quantum phenomena often spark worry about collisions with Einstein's theory of special relativity. 



Yet nothing in these experiments hints that any object can outrun light. Photons here do not convey information faster than physical laws permit, so there is no conflict with long-accepted principles.



Some have questioned whether labeling this interval as negative time might invite confusion. 



The team is aware that such language can sound surreal, but they believe it captures the unusual nature of quantum measurements that drift from usual expectations.



<h2 class="wp-block-heading" id="h-photons-and-probabilities">Photons and probabilities</h2>



<a href="https://www.earth.com/news/quantum-dance-entangled-photons-wave-functions-captured-real-time/" target="_blank" rel="noreferrer noopener">Photons have a split personality</a>, sometimes acting like particles and other times behaving like waves. 



They follow probability rules that let them appear in multiple states at once, prompting a range of possible outcomes. This fuzziness underpins the notion that events do not always fit into a neat timeline.



In standard settings, photons pass through materials in ways consistent with well-established physics. 



But in the group’s experiments, certain measurements produce results that slip into territory most would never predict. 



These findings spark curiosity about how <a href="https://www.earth.com/news/impossibility-paradox-calculating-incalculable-quantum-realm-particles/" target="_blank" rel="noreferrer noopener">quantum mechanics</a> can present effects that appear at odds with common sense.



<h2 class="wp-block-heading" id="h-reactions-and-skepticism">Reactions and skepticism</h2>



The concept has captured the attention of many, including German theoretical physicist <a href="https://www.youtube.com/watch?v=ErLHm-1c6I4" target="_blank" rel="noreferrer noopener">Sabine Hossenfelder</a>, who remains unimpressed. 



"The negative time in this experiment has nothing to do with the passage of time -- it's just a way to describe how photons travel through a medium and how their phases shift," she said in a YouTube video with more than 250,000 views.



Some observers suspect the term negative time is too dramatic and misrepresents the study’s scope. Others argue that a fresh approach could encourage deeper conversations about how quantum processes unfold. 



The researchers maintain they are not rewriting the rules of physics but aiming to highlight the weirdness at play in <a href="https://www.earth.com/news/quantum-tunneling-allow-particles-break-light-speed-barrier/" target="_blank" rel="noreferrer noopener">fundamental experiments</a>.



<h2 class="wp-block-heading" id="h-next-steps-for-negative-time-studies">Next steps for "negative time" studies</h2>



"We've made our choice about what we think is a fruitful way to describe the results," Steinberg said, adding that while practical applications remain elusive, the findings open new avenues for exploring <a href="https://www.earth.com/news/how-quantum-revolution-will-impact-all-aspects-of-society/" target="_blank" rel="noreferrer noopener">quantum phenomena</a>. 



He acknowledged that many remain skeptical, but he insists the numbers speak for themselves. No serious criticism has challenged their raw data.



"I'll be honest, I don't currently have a path from what we've been looking at toward applications," Steinberg admitted. "We're going to keep thinking about it, but I don't want to get people's hopes up."



Whether the idea of negative time transforms into something with everyday uses remains to be seen, yet the curiosity it sparks is hard to ignore.



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



To sum it all up, quantum physics has always pushed boundaries, forcing researchers to adjust old assumptions. 



These experiments from the University of Toronto team serve as another reminder that the world behaves in ways that do not always match common intuition. Still, they stress that no claims of <a href="https://www.earth.com/news/astrophysicist-says-hes-cracked-the-equation-for-time-travel/" target="_blank" rel="noreferrer noopener">time travel</a> are on the table.



By presenting evidence that something can measure out to less than zero time, these researchers have challenged expectations about how light interacts with matter. 



For now, the puzzle remains a subject of debate. Unraveling the enigma might take further studies, but many agree that investigating such <a href="https://www.earth.com/news/google-record-shattering-quantum-ai-chip-accesses-parallel-universes/" target="_blank" rel="noreferrer noopener">bizarre possibilities</a> is part of the ongoing effort to understand quantum reality.



The results highlight how experiments can produce outcomes that differ from conventional thinking. Negative intervals in absorption times remain an intriguing piece of a much broader puzzle.



Scientists continue to refine experiments and weigh alternative explanations. Despite lingering questions, the project stands as a reminder that quantum behavior can seem downright strange, to put it mildly.



The full study was published in the journal <a href="https://arxiv.org/abs/2409.03680" target="_blank" rel="noreferrer noopener">arXiv</a>.



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"Negative time" observed in new quantum experiments, surprising scientists

It is widely known among scientists that light sometimes appears...

The Baltic Sea, one of the world’s youngest bodies of water, has long been known to host Atlantic and Baltic herring - plankton-eating fish critical to northern marine ecosystems.&nbsp;



Yet new research, published in the journal <a href="http://dx.doi.org/10.1038/s41467-024-55216-8" target="_blank" rel="noreferrer noopener">Nature Communications</a>, has uncovered a surprising adaptation in this environment: genetically distinct, fish-eating Baltic herring (Sardinops sagax caerulea). 



Conducted by scientists at <a href="https://www.uu.se/en" target="_blank" rel="noreferrer noopener">Uppsala University</a> in Sweden, the study challenges traditional assumptions about how Baltic herring evolved and found new ecological niches in brackish waters formed at the end of the last Ice Age.



<h2 class="wp-block-heading" id="h-herring-in-the-baltic-sea">Herring in the Baltic Sea</h2>



Herring serve a crucial function in the Atlantic Ocean and the <a href="https://www.earth.com/news/toxic-thallium-levels-are-rising-in-the-baltic-sea/" target="_blank" rel="noreferrer noopener">Baltic Sea</a>, transferring energy from plankton up the food chain to predatory fish, seabirds, marine mammals, and humans. 



Previous studies by the Uppsala group had already established that herring populations adapt genetically to variations in climate, salinity, and spawning seasons.&nbsp;



However, the newly discovered fish-eating Baltic herring adds an intriguing twist: these larger individuals exhibit distinct biological and genetic characteristics that set them apart from the traditional plankton-eating varieties.



<h2 class="wp-block-heading" id="h-the-baltic-herring-enigma">The Baltic herring enigma</h2>



Renowned Swedish taxonomist Carl Linnaeus once defined the Baltic herring as a subspecies of the Atlantic herring, specifically adapted to the Baltic’s brackish waters. Over the centuries, scientists have consistently noted how Baltic herring are generally smaller and contain less fat than their Atlantic relatives.&nbsp;



But when a local fisherman near Uppsala spoke of a large herring “that always spawns just before midsummer and which is as big as the Atlantic herring,” questions arose as to whether a previously unidentified herring population existed within the Baltic.



The study was led by Leif Andersson, a professor at the Department of Medical Biochemistry and Microbiology at Uppsala University.



“When I learned that the locals are aware of a specific population of very large Baltic herring that always spawns in the same area year after year, I decided to sample and explore their genetic constitution,” said Professor Andersson.&nbsp;



“Now we know that this is a genetically unique population that must have evolved over hundreds, if not thousands, of years in the Baltic Sea.”&nbsp;



<h2 class="wp-block-heading" id="h-switching-to-a-fish-based-diet">Switching to a fish-based diet</h2>



By collecting samples of these large herring, researchers noticed striking differences from the smaller, <a href="https://www.earth.com/news/plankton-at-risk-global-warming-threatens-the-oceans-lifeline/" target="_blank" rel="noreferrer noopener">plankton</a>-eating Baltic herring. 



Physical examinations, growth measurements, and fat-content analyses revealed that the larger herring contain higher levels of fat and show signs of damaged gill rakers - features aligning with a switch from filtering plankton to eating fish such as the common stickleback, which has sharp defensive spines.



According to the scientists, the relatively low dioxin content makes this fish-eating Baltic herring interesting for human consumption. With a faster growth rate and lower pollutant load, the fish-eating herring may offer both ecological and nutritional advantages.



<h2 class="wp-block-heading" id="h-uncovering-two-genetic-subpopulations">Uncovering two genetic subpopulations</h2>



Once it became clear that these larger Baltic herring were genetically distinct, the scientists expanded their focus, comparing samples of big herring from different Baltic locations. Whole genome sequencing confirmed that these fish fall into two separate subpopulations.



“Our genetic analysis demonstrates that there are at least two distinct subpopulations of fish-eating herring in the Baltic Sea; one occurs north of Stockholm, and the other occurs south of Stockholm,” said lead author Jake Goodall, a researcher at Uppsala University.&nbsp;



By identifying multiple genetic groups, the study reveals even greater diversity within the Baltic herring gene pool than previously thought.



<h2 class="wp-block-heading" id="h-why-fish-eating-herring-evolved-in-the-baltic">Why fish-eating herring evolved in the Baltic</h2>



The Baltic Sea, with salinity levels far lower than the Atlantic’s, has existed for only around 8,000 years. Such an environment is inhospitable to many <a href="https://www.earth.com/news/climate-change-disrupts-the-distribution-of-marine-species/" target="_blank" rel="noreferrer noopener">marine species</a>, and only a select few have successfully established populations there. 



The researchers propose that fish-eating herring have emerged due to a scarcity of competing predators, making it advantageous for some herring to exploit fish as a food source.



“We hypothesize that fish-eating Baltic herring have evolved due to a lack of competition from other <a href="https://www.earth.com/news/jellyfish-more-than-just-a-snack-for-predatory-fish/" target="_blank" rel="noreferrer noopener">predatory fish</a>, for instance, mackerel and tuna, which do not occur where we find fish-eating herring,” said Andersson.



“Thus, these herring take advantage of an underutilised food resource in the Baltic Sea.”



The ability to feed on smaller fish rather than plankton likely opened an ecological niche that larger herring could occupy, capitalizing on prey that other species could not exploit.



<h2 class="wp-block-heading" id="h-balancing-ecosystems-and-human-needs">Balancing ecosystems and human needs</h2>



The emergence of fish-eating Baltic herring underscores the Baltic Sea’s capacity to foster evolutionary innovations. As a keystone species, herring regulate energy flow in their ecosystem.&nbsp;



The discovery of these large, fish-feeding populations highlights the adaptability of herring to different diets, environmental pressures, and competition. It also suggests that such herring may provide a safer, fattier food option for consumers, given their comparatively lower dioxin levels.



These insights could inform <a href="https://www.earth.com/news/sustainable-fishing-gets-a-boost-from-genomics-roadmap/" target="_blank" rel="noreferrer noopener">fishery management</a> and conservation strategies, ensuring that as the Baltic continues to evolve, both ecosystem integrity and human consumption interests remain aligned.



<h2 class="wp-block-heading" id="h-rapid-evolutionary-change-of-baltic-herring-nbsp">Rapid evolutionary change of Baltic herring&nbsp;</h2>



Because the Baltic Sea is geologically recent, this discovery showcases how quickly species can adapt to novel conditions.&nbsp;



The fish-eating herring’s genetic distinctiveness, alongside significant physical and dietary differences, underlines the dynamic nature of evolution in brackish environments.&nbsp;



For scientists and policymakers, these findings serve as a reminder that even seemingly uniform species can harbor hidden diversity essential for resilience in changing waters.



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Rapid evolution in the Baltic Sea: How herring became fish-eaters

The Baltic Sea, one of the world’s youngest bodies of...

As the holiday season approaches, homes worldwide are decorated with evergreen conifers like spruce and pine. Beyond spreading warmth and joy as Christmas trees, these resilient conifers thrive in harsh natural environments - enduring everything from frigid winters to intense sunlight in boreal forests.



Scientists at Umeå University are shedding light on how these remarkable trees endure such adversities and remain lush and green year-round.



The experts found that conifers possess unique adaptations that allow them to thrive in some of the planet's most challenging environments.



The findings not only deepen our understanding of conifers but also hint at potential applications in conservation and crop resilience.



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



Conifer trees are some of the most recognizable and <a href="https://www.earth.com/news/why-do-some-leaves-live-longer-than-others/" target="_blank" rel="noreferrer noopener">evergreen giants</a> you’ll find in forests around the world. Think of pine, spruce, fir, and cedar trees with their needle-like leaves and sturdy cones. 



These trees are well adapted to various climates, especially colder and drier regions, because their shape helps them shed snow and conserve water.



Conifers have been around for millions of years, dominating many landscapes long before flowering plants took the stage. 



Their evergreen nature means they <a href="https://www.earth.com/news/unexpected-changes-what-happens-to-boreal-forests-after-fire/" target="_blank" rel="noreferrer noopener">stay green</a> all year round, providing a constant splash of color even during the bleakest winters.



Beyond their striking appearance, conifer trees play a crucial role in the environment and our daily lives. They are vital for producing oxygen and absorbing carbon dioxide, helping to combat climate change. 



The wood from conifers is used in building everything from homes to paper products, making them <a href="https://www.earth.com/news/which-trees-are-best-at-purifying-the-air/" target="_blank" rel="noreferrer noopener">essential to many industries</a>. 



Plus, conifer forests are home to countless wildlife species, offering habitats and food sources for animals like birds, squirrels, and deer.



<h2 class="wp-block-heading" id="h-photosynthesis-strategies-of-conifers">Photosynthesis strategies of conifers</h2>



The process of photosynthesis is conserved across most plants, yet conifers exhibit <a href="https://www.earth.com/news/resilient-trees-can-help-safeguard-cities-from-climate-change/" target="_blank" rel="noreferrer noopener">distinct strategies</a> that set them apart. 



One such adaptation is a structural change in their thylakoid membranes - the sites where photosynthesis occurs. During winter, Photosystem I (PSI) and Photosystem II (PSII), typically separated in most plants, come closer together in a phenomenon known as spill-over.



"This helps them to safely dissipate extra energy and avoid damage from too much sunlight in the cold," explained Stefan Jansson, a professor in the <a href="https://www.upsc.se" target="_blank" rel="noreferrer noopener">Umeå Plant Science Center</a>.



This mechanism prevents excess light from overwhelming their photosynthetic machinery, enabling them to survive harsh winters unscathed.



Previously, researchers referred to this process as "sustained quenching," likening it to a photosynthetic lockdown. However, the precise mechanism remained a mystery.



<h2 class="wp-block-heading" id="h-alternative-electron-flow">Alternative electron flow</h2>



In addition to spill-over, conifers possess a second survival strategy: alternative electron flow - a key aspect of their resilience in harsh winter environments.



This method involves the use of&nbsp;flavodiiron proteins, which redirect electrons during <a href="https://www.earth.com/news/trees-cleverly-adapt-to-withstand-storms-and-high-winds/" target="_blank" rel="noreferrer noopener">photosynthesis</a>. This redirection ensures that the photosynthetic system remains balanced, even when faced with intense sunlight and freezing temperatures.



Alternative electron flow acts as a backup mechanism to handle excess energy, preventing the photosynthetic machinery from becoming overloaded and damaged. 



This is particularly critical in winter when sunlight can be strong but the freezing conditions make energy dissipation challenging.



Together with&nbsp;spill-over, where Photosystem I (PSI) and Photosystem II (PSII) collaborate to dissipate extra energy, these strategies form a dual defense system. 



Spill-over reduces the risk of light-induced damage, while alternative electron flow maintains the system's stability.



<h2 class="wp-block-heading" id="h-unique-adaptations-of-conifers">Unique adaptations of conifers</h2>



Conifers' photosynthetic apparatus also diverges from that of flowering plants (angiosperms) in other significant ways. 



For instance, they lack certain light-harvesting proteins found in angiosperms. This unique configuration might explain why conifers thrive in nutrient-poor, cold, and water-scarce environments.



"All together, this can explain why conifers are the dominant species in boreal forests, thriving where few others can, perhaps at the expense of advantages during less <a href="https://www.earth.com/news/planting-trees-in-the-wrong-place-can-make-cities-hotter/" target="_blank" rel="noreferrer noopener">challenging conditions</a>," noted Pushan Bag, lead author of the study.



<h2 class="wp-block-heading" id="h-implications-for-crop-resilience">Implications for crop resilience </h2>



Understanding the survival mechanisms of conifers goes beyond academic curiosity. As the climate changes, insights into how conifers adapt to extreme conditions may inform conservation strategies and predict forest responses to new environmental <a href="https://www.earth.com/news/tree-diversity-makes-forests-more-resilient-against-storms/" target="_blank" rel="noreferrer noopener">challenges</a>.



These findings could also guide the development of crops that are resilient to extreme weather, ensuring food security in an unpredictable future.



"This paper highlights the intricate adaptations of conifers to extreme winter conditions. By combining structural, molecular, and evolutionary insights, it advances our understanding of how these trees have come to dominate some of the harshest ecosystems on Earth," said study co-author Alexander Ivanov.



<h2 class="wp-block-heading" id="h-incredible-resilience-of-conifers">Incredible resilience of conifers</h2>



Conifers’ ability to adapt and thrive in severe conditions is a proof of <a href="https://www.earth.com/news/trees-are-in-big-trouble-and-scientists-are-sounding-the-alarm/" target="_blank" rel="noreferrer noopener">nature's ingenuity</a>. Their unique photosynthetic strategies, refined over millennia, ensure their survival in environments where most plants would falter.



As researchers continue to explore these mechanisms, they uncover not only the secrets of these hardy evergreens but also pathways to address pressing challenges like climate change and food insecurity.



This festive season, as you admire the beauty of a Christmas tree, take a moment to appreciate the incredible resilience and <a href="https://www.earth.com/news/can-trees-protect-their-genetic-diversity-for-millions-of-years/" target="_blank" rel="noreferrer noopener">evolutionary brilliance</a> of conifers. 



They are not just symbols of joy and celebration but also living proof of nature's ability to overcome adversity.



The study is published in the journal <a href="https://www.cell.com/trends/plant-science/fulltext/S1360-1385(24)00300-5" target="_blank" rel="noreferrer noopener">Trends in Plant Science</a>.



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Christmas trees have unique strategies to survive harsh winters

As the holiday season approaches, homes worldwide are decorated with...

The world’s largest iceberg has astonished scientists by shaking free from a spinning ocean trap and continuing its trek across remote southern waters.



Its journey, marked by twists and turns since it separated from Antarctica, has become a focus for research on the changing ocean and the ice’s influence on life beneath the surface.



<h2 class="wp-block-heading" id="h-a23a-iceberg-breaks-free">A23a iceberg breaks free</h2>



The icy slab covers about 1,418 square miles, which makes it bigger than Rhode Island. 



It originally broke away from <a href="https://eros.usgs.gov/earthshots/filchner-ice-shelf-antarctica" target="_blank" rel="noreferrer noopener">Antarctica’s Filchner-Ronne Ice Shelf</a> in 1986 and remained stuck close to the continent for decades. 



Ocean currents and seafloor topography restricted its path. After finally regaining momentum last year, the towering block ran into a swirling formation of water near the <a href="https://www.ndsu.edu/subantarctic/southorkney.htm">South Orkney Islands</a>, where it ended up spinning in place for months.



<h2 class="wp-block-heading" id="h-tracking-iceberg-movements-in-the-ocean">Tracking iceberg movements in the ocean</h2>



“It’s exciting to see A23a on the move again after periods of being stuck,” said <a href="https://www.bas.ac.uk/media-post/worlds-largest-iceberg-a23a-breaks-free/">Dr Andrew Meijers</a>, an oceanographer at the British Antarctic Survey.



Ocean experts have been monitoring this <a href="https://www.earth.com/news/worlds-largest-iceberg-a23a-undergoing-major-erosion/" target="_blank" rel="noreferrer noopener">iceberg’s</a> every move to understand how such massive blocks can influence sea circulation, temperature balance, and the distribution of nutrients.



<h2 class="wp-block-heading" id="h-new-chapter-for-the-a23a-iceberg">New chapter for the A23a iceberg</h2>



The <a href="https://www.earth.com/news/birth-of-an-iceberg-a-83-breaks-free-from-antarctica/" target="_blank" rel="noreferrer noopener">iceberg’s</a> latest departure from its watery prison has stirred up fresh discussions about its fate. 



As it progresses northward, warmer seas may take a toll on its bulk. Many large ice masses follow a similar route before gradually disintegrating. Scientists emphasize that ice already afloat in the water does not raise sea levels when it melts. That does not mean these events should be dismissed, though, since Antarctica’s overall health is a concern in a warming world.



<h2 class="wp-block-heading" id="h-a23a-iceberg-and-its-ocean-impacts-nbsp">A23a iceberg and its ocean impacts&nbsp;</h2>



Researchers have pointed out that although this particular <a href="https://www.earth.com/news/iceberg-that-weighs-more-than-the-eiffel-tower-is-floating-freely/" target="_blank" rel="noreferrer noopener">iceberg</a> calved naturally, Antarctic ice shelves are showing other, more concerning changes.



Experts worry that accelerated ice loss in certain areas could have far-reaching effects. Even small changes along coastal regions of the continent can result in shifts in glacial flow, which might eventually lead to an uptick in sea-level rise. 



Data gathered from icebergs like A23a helps build a clearer picture of these wider trends.



<h2 class="wp-block-heading" id="h-ecosystems-under-the-ice">Ecosystems under the ice</h2>



Observations have shown that drifting ice blocks can stir the waters they pass through, sometimes generating short-lived plankton blooms. 



These blooms support fish, krill, and other marine life in areas that might otherwise lack resources. "These icebergs provide different sources of nutrients," explained Professor <a href="https://www.bas.ac.uk/profile/gant/" target="_blank" rel="noreferrer noopener">Geraint Tarling</a>, Biopole's principal investigator. By sampling the water where the giant iceberg has traveled, scientists hope to gauge whether this berg’s size and origin play a notable part in shaping ocean communities.



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



Many anticipate that <a href="https://www.earth.com/news/a23a-worlds-largest-iceberg-is-moving-after-30-years/" target="_blank" rel="noreferrer noopener">A23a</a> will continue meandering through the Southern Ocean currents. As it ventures closer to milder latitudes, the ice is expected to weaken and break into smaller chunks. 



Some fragments may persist for a while, but the main body of the iceberg will likely diminish.



<h2 class="wp-block-heading" id="h-a23a-iceberg-research-enhances-ocean-circulation">A23a iceberg research enhances ocean circulation</h2>



Ongoing research on these gargantuan ice blocks helps experts refine climate models, track ocean circulation patterns, and pinpoint areas most vulnerable to environmental changes. 



Observations from ships, satellites, and on-site measurements all combine to offer a clearer view of what is happening far from major population centers. The hope is that findings from the watery trails left by A23a will guide future decisions on how we manage and protect polar waters and fragile marine habitats.



<h2 class="wp-block-heading" id="h-moving-lab-for-ocean-studies">Moving lab for ocean studies</h2>



A23a’s odyssey is important because it shows how an individual iceberg can become a moving lab for oceanographers and climate scientists. 



The iceberg's escape from a rotating water column this month hints at nature’s complexity, from shifting ocean currents to unseen underwater topography.



While it has been around for nearly four decades, its path in the coming months may reveal more about the chain reactions set in motion when a piece of Antarctica sets sail for open waters.



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World’s largest iceberg breaks free from ocean cyclone

The world’s largest iceberg has astonished scientists by shaking free...

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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

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

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



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



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



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



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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



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



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



Video Credit: American Chemical Society&nbsp;



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



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

Detecting mercury contamination with the tap of a finger

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

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



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



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



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



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



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



Video/ Image Credit: European Space Agency&nbsp;



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



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

Kainji Lake in north central Nigeria

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



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



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



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



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



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



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



Video Credit: Amanda Nguyen/University of Illinois



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



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

Designing crops that can beat the heat

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

The Portuguese man o&#8217; war, also known as the man-of-war, bluebottle, or blue bottle jellyfish, is a marine hydrozoan found in the Atlantic Ocean and the Indian Ocean. The Portuguese Man-o-War has a signature translucent blue and purple coloring, which helps provide camouflage in the blue ocean waves.

Portuguese Man O' War

The Brazilian rainbow boa is a medium-sized boa native to the Amazon River basin. It is named for its iridescent skin which refracts light and creates a rainbow.