Today's Image of the Day from the European Space Agency features a pair of interacting spiral galaxies known as the Antennae Galaxies. They are located approximately 45 million light-years away in the constellation Corvus.&nbsp;



<h2 class="wp-block-heading" id="h-antennae-galaxies-in-a-deadly-embrace">Antennae Galaxies in a deadly embrace </h2>



“The NASA/ESA Hubble Space Telescope has snapped the best ever image of the Antennae Galaxies. Hubble has released images of these stunning galaxies twice before, once using observations from its Wide Field and Planetary Camera 2 (WFPC2) in 1997, and again in 2006 from the Advanced Camera for Surveys (ACS),” noted <a href="https://esahubble.org/images/potw1345a/" target="_blank" rel="noreferrer noopener">ESA</a>.



“The galaxies - also known as NGC 4038 and NGC 4039 - are locked in a deadly embrace. Once normal, sedate spiral galaxies like the Milky Way, the pair have spent the past few hundred million years sparring with one another.”



According to ESA, the clash of the Antennae Galaxies is so violent that stars have been ripped from their host <a href="https://www.earth.com/news/galaxy-collision-2-million-mph-stephans-quintet-captured-unprecedented-detail/" target="_blank" rel="noreferrer noopener">galaxies</a> to form a streaming arc between the two.&nbsp;



The name "Antennae" comes from this long stream of stars and gas, which resembles insect antennae.



<h2 class="wp-block-heading" id="h-intense-bursts-of-star-formation-nbsp">Intense bursts of star formation&nbsp;</h2>



The collision has triggered intense bursts of star formation, making the Antennae Galaxies one of the nearest and most dramatic examples of a starburst galaxy.&nbsp;



Many of the newly formed stars are concentrated in massive star clusters, some of which are expected to evolve into globular clusters over millions of years.



“This new image of the Antennae Galaxies shows obvious signs of chaos. Clouds of gas are seen in bright pink and red, surrounding the bright flashes of blue star-forming regions - some of which are partially obscured by dark patches of dust,” explained ESA.



“The rate of star formation is so high that the Antennae Galaxies are said to be in a state of starburst, a period in which all of the gas within the galaxies is being used to form stars.”&nbsp;



“This cannot last forever and neither can the separate galaxies; eventually the nuclei will coalesce, and the galaxies will begin their retirement together as one large elliptical galaxy.”



<h2 class="wp-block-heading" id="h-significance-of-the-antennae-galaxies">Significance of the Antennae Galaxies</h2>



The Antennae Galaxies are one of the most well-studied examples of galaxy collisions, offering insight into the processes that shape galaxies over time.



Astronomers study the Antennae Galaxies using a range of telescopes across different wavelengths, including visible light, infrared, and X-rays.&nbsp;



Observations in X-rays have revealed evidence of supernovae and <a href="https://www.earth.com/news/black-holes-may-talk-to-galaxies-through-energetic-winds/" target="_blank" rel="noreferrer noopener">black holes</a>, while infrared studies highlight regions of dust and star formation.&nbsp;



<h2 class="wp-block-heading" id="h-the-milky-way-s-collision-course-nbsp">The Milky Way's collision course&nbsp;</h2>



The Antennae Galaxies provide a glimpse into the future of our <a href="https://www.earth.com/news/uma3-u1-faintest-star-system-found-orbiting-milky-way-galaxy/" target="_blank" rel="noreferrer noopener">Milky Way</a>, which is expected to eventually merge with the Andromeda Galaxy - our closest spiral galaxy neighbor.



The cosmic collision course of the Milky Way and Andromeda will reshape both galaxies over billions of years.&nbsp;



This event is expected to occur in about 4.5 billion years. Both galaxies are part of the Local Group, a cluster of galaxies bound together by gravity. Their mutual gravitational pull is drawing them closer at a speed of approximately 110 kilometers per second.



<h2 class="wp-block-heading" id="h-the-birth-of-an-elliptical-galaxy-nbsp">The birth of an elliptical galaxy&nbsp;</h2>



When the two galaxies collide, their individual stars will largely avoid direct collisions due to the vast distances between them. However, the gravitational forces involved will create dramatic effects.&nbsp;



These forces will distort the galaxies' <a href="https://www.earth.com/news/shapes-of-one-million-galaxies-hint-at-the-universes-origins/" target="_blank" rel="noreferrer noopener">shapes</a>, triggering intense bursts of star formation as gas clouds collide and compress. Over time, the galaxies will settle into a new, larger elliptical galaxy often referred to as "Milkomeda" or "Milkdromeda" by astronomers.



<h2 class="wp-block-heading" id="h-galaxy-merger-and-the-solar-system">Galaxy merger and the solar system</h2>



Despite the seemingly destructive nature of the collision, the solar system is unlikely to face direct harm. Our Sun may find itself flung into a new orbit within the merged galaxy or even cast into intergalactic space.&nbsp;



The merger will also significantly alter the night sky, with the Andromeda Galaxy becoming increasingly prominent before blending into the unified structure.



This event is part of the natural <a href="https://www.earth.com/news/galaxies-are-much-bigger-than-we-originally-believed-gas-clouds/" target="_blank" rel="noreferrer noopener">evolution of galaxies</a> and serves as a fascinating reminder of the dynamic and ever-changing nature of the universe. 



While the collision is still billions of years away, studying it helps astronomers understand galactic interactions and the long-term future of our cosmic neighborhood.



Image Credit: ESA/Hubble &amp; NASA



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The violent clash of the Antennae Galaxies  

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

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 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 

The universe is packed with intricate, carbon-based compounds, including organic molecules, that hold clues about life’s raw materials. Some of these compounds are found in space.



Over the past few years, robotic missions have taken samples from comets and asteroids to learn how these compounds formed and whether our planet might owe its biological chemistry to faraway dust clouds.



The findings hint that organic molecules appear in every corner of space, which suggests that our own evolution may fit into a larger cosmic narrative.



<h2 class="wp-block-heading" id="h-organic-molecules-in-space">Organic molecules in space</h2>



Scientists studying bits of <a href="https://www.earth.com/news/worlds-largest-iceberg-a23a-undergoing-major-erosion/" target="_blank" rel="noreferrer noopener">interstellar</a> dust, comets, and asteroids keep finding the same theme: these objects contain a variety of organic molecules. The story began in 1986 when the <a href="https://www.esa.int/Science_Exploration/Space_Science/Giotto_overview" target="_blank" rel="noreferrer noopener">European Giotto spacecraft </a>conducted the first in-situ analysis of a comet, <a href="https://www.space.unibe.ch/about_us/personen/dr_haenni_nora/index_eng.html" target="_blank" rel="noreferrer noopener">1P/</a><a href="https://www.earth.com/news/eta-aquarids-see-up-to-50-shooting-stars-per-hour-this-weekend/" target="_blank" rel="noreferrer noopener">Halley</a>, during its apparition (when it was visible from Earth). It revealed an unexpected abundance of organic species in the coma, but their exact origins -- whether from polymeric matter or smaller molecules -- remained unclear. The small spacecraft followed the comet for two years, capturing the dust and gas it shed. Instruments recorded dozens of molecules that contained carbon, leading scientists to look deeper for connections to the <a href="https://www.earth.com/news/living-in-submarines-can-help-astronauts-prepare-for-future-space-missions/" target="_blank" rel="noreferrer noopener">early solar system</a>.



<h2 class="wp-block-heading" id="h-past-records-of-organic-molecules-in-space">Past records of organic molecules in space</h2>



The <a href="https://www.swri.org/press-release/rosetta-data-reveals-more-surprises-about-comet-67p">Rosetta</a> spacecraft was the first to orbit and land on a comet, namely 67P. In 2015, it detected simple organic compounds, including <a href="https://www.science.org/doi/10.1126/sciadv.1600285">glycine</a>, which is a building block of proteins. This discovery marked the first direct detection of this molecule on a comet. By 2022, researchers analyzing high-resolution mass spectrometry data <a href="https://www.nature.com/articles/s41467-022-31346-9" target="_blank" rel="noreferrer noopener">identified</a> 44 organic compounds in just one day’s worth of Rosetta data, with some molecules weighing up to 140 Daltons (Da). “Rosetta really changed the view,” said <a href="https://www.space.unibe.ch/about_us/personen/dr_haenni_nora/index_eng.html" target="_blank" rel="noreferrer noopener">Dr. Nora Hänni</a>, a chemist at the <a href="https://www.unibe.ch/index_eng.html" target="_blank" rel="noreferrer noopener">University of Bern</a>. Soon after this, her team identified dimethyl sulfide, a gas that, on Earth, is generally produced by living organisms.



<h2 class="wp-block-heading" id="h-asteroids-as-cosmic-sample-returns">Asteroids as cosmic sample returns</h2>



Japan’s <a href="https://science.nasa.gov/mission/hayabusa-2/" target="_blank" rel="noreferrer noopener">Hayabusa2</a> and NASA’s <a href="https://science.nasa.gov/mission/osiris-rex/" target="_blank" rel="noreferrer noopener">OSIRIS-REx</a> missions offered a similar look at ancient space rocks. They scooped material from asteroids Ryugu and Bennu and brought the samples back to Earth. Early analyses suggested that both asteroids have a wide range of organics present. <a href="https://www.science.org/doi/10.1126/science.abn7850" target="_blank" rel="noreferrer noopener">Scientists</a> studying <a href="https://www.earth.com/news/asteroid-ryugu-has-unexpected-family-ties-near-jupiter/" target="_blank" rel="noreferrer noopener">Ryugu</a> found at least 20,000 varieties of carbon-based compounds, including 15 different amino acids. “It’s just everything possible from which life could emerge,” said <a href="https://www.helmholtz-munich.de/en/bgc/pi/philippe-schmitt-kopplin" target="_blank" rel="noreferrer noopener">Philippe Schmitt-Kopplin</a>, an organic geoscientist at the Technical University of Munich.



<h2 class="wp-block-heading" id="h-questions-about-planetary-origins">Questions about planetary origins</h2>



Those organic-rich rocks may date back to a time before planets fully formed. Scientists wonder if these compounds started in cold, dark clouds between stars, or if they originated in energetic zones near young suns.&nbsp;



“Those of us interested in searching for life have to understand how planets could acquire organics in the absence of life,” said <a href="https://astrobiology.nasa.gov/nai/directory/glein-christopher/index.html" target="_blank" rel="noreferrer noopener">Christopher Glein</a>, a planetary scientist at the Southwest Research Institute. Many experts ask whether the early Earth became <a href="https://www.earth.com/news/expanding-the-search-for-extraterrestrial-life/" target="_blank" rel="noreferrer noopener">habitable</a> partly because of organic molecules that arrived from space. “I would like to know where we come from as a planetary species,” said <a href="https://astronomy.fas.harvard.edu/people/karin-oberg" target="_blank" rel="noreferrer noopener">Karin Öberg</a>, an astrochemist at <a href="https://www.harvard.edu" target="_blank" rel="noreferrer noopener">Harvard University</a>.



<h2 class="wp-block-heading" id="h-early-chemistry-across-the-cosmos">Early chemistry across the cosmos</h2>



Astronomers have traced certain hefty carbon structures called polycyclic aromatic hydrocarbons (<a href="https://www.nature.com/articles/s41586-023-05998-6" target="_blank" rel="noreferrer noopener">PAHs</a>) back to about 1.5 billion years after the Big Bang.



Carbon atoms often form large, sturdy rings and chains in the outflows of dying stars. “It’s actually not too different from combustion as we understand it here on Earth,” said Öberg, referring to the ways these molecules can build up in stellar winds. 



Observations confirm that interstellar <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">space</a> has more than 200 carbon-containing compounds.



<h2 class="wp-block-heading" id="h-icy-labs-in-the-dark">Icy labs in the dark</h2>



In molecular clouds, simple ingredients gather on cold dust grains. Once stuck together, atoms can combine to form key molecules like methane. Over time, ultraviolet radiation and cosmic rays split molecules into radical fragments, which recombine to form something new. Experiments hint that this can produce anything from methanol to glycine “You can build complexity without much going on in just a cold, dark cloud,” said <a href="https://www.cfa.harvard.edu/people/alice-s-booth" target="_blank" rel="noreferrer noopener">Alice Booth</a>, an astronomer at Harvard University.



<h2 class="wp-block-heading" id="h-planetary-disks-and-newborn-worlds">Planetary disks and newborn worlds</h2>



Observations of protoplanetary disks -- thick, spinning layers of dust and gas around baby stars -- show that methanol and other organics survive the intense heat of stellar births. Recent modeling suggests these compounds may grow into even more sophisticated structures when disk materials cycle between hot surface zones and cooler midplane regions. This process could be one reason comets and asteroids wind up so chemically rich by the time they form. “Comets are, I think, the best that we can do to go back in time,” said Hänni.



<h2 class="wp-block-heading" id="h-origins-of-organic-molecules-in-space">Origins of organic molecules in space</h2>



When organic chemicals land on a planet, they might set the stage for the emergence of living systems. A few theories propose that meteorites or comets delivered certain amino acids or <a href="https://www.epa.gov/sites/default/files/2014-03/documents/pahs_factsheet_cdc_2013.pdf" target="_blank" rel="noreferrer noopener">PAHs</a> to early Earth.



Astrobiologists debate about which molecules represent a solid proof of life, and which might be possible false positives. 



The presence of dimethyl sulfide from comet 67P, supports the idea that lifeless processes can make molecules that we tend to associate with living organisms.



In 2016, <a href="https://www.esa.int/Science_Exploration/Space_Science/Rosetta" target="_blank" rel="noreferrer noopener">Rosetta</a> concluded its mission with a controlled impact on comet 67P’s surface, which resulted in a rich legacy of data for further analysis.



Since then, scientists have connected these findings to other Solar System reservoirs of organics, such as Saturn’s ring rain and meteoritic material, revealing their shared prestellar origins.



<h2 class="wp-block-heading" id="h-future-research-on-organic-molecules-in-space">Future research on organic molecules in space</h2>



Scientists will continue exploring these mysteries with missions like NASA’s <a href="https://science.nasa.gov/mission/europa-clipper/" target="_blank" rel="noreferrer noopener">Europa Clipper</a>, the European Space Agency’s <a href="https://www.esa.int/Science_Exploration/Space_Science/Juice" target="_blank" rel="noreferrer noopener">Juice</a>, and a future rotorcraft bound for Saturn’s moon Titan.



Researchers hope to spot organic compounds that might give hints about oceans hiding beneath icy crusts. 



Such discoveries could bring us closer to answering one of humanity's oldest questions: are we alone in the <a href="https://www.earth.com/news/europa-clipper-mission-set-to-search-for-life-on-jupiters-ocean-moon/" target="_blank" rel="noreferrer noopener">universe</a>?



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Organic molecules found throughout the universe hint that life began in deep space

The universe is packed with intricate, carbon-based compounds, including organic...

In the relentless battle between parasites and their hosts, nature often finds innovative solutions. Sometimes, however, borrowing proven strategies can trump the invention of new ones. 



This principle is exemplified by fruit flies, which have adopted a defense mechanism from bacteria to help them counter predatory wasps. The fascinating discovery highlights the dynamic strategies of evolution.



<h2 class="wp-block-heading" id="h-parasitic-wasps-vs-fruit-flies">Parasitic wasps vs. fruit flies</h2>



Parasitic wasps present a gruesome threat to <a href="https://www.earth.com/news/fruit-flies-can-walk-jump-and-dance-using-the-same-motor-neurons/" target="_blank" rel="noreferrer noopener">fruit flies</a>, as they transform fly larvae into hosts for wasp offspring. In some species, parasitism affects nearly half of all fly larvae, in a process that is eerily reminiscent of the 1979 movie&nbsp;Alien. 



To survive this biological invasion, fruit flies have co-opted a bacterial defense mechanism, showcasing a remarkable example of horizontal gene transfer (HGT) in animals.



Horizontal gene transfer, where genes jump between unrelated species, is common among bacteria and viruses. It plays a crucial role in spreading antibiotic resistance among microbes. 



However, HGT is considered rare in multicellular organisms, such as insects and humans. This study challenges that notion, and demonstrates how animals might also leverage HGT for rapid adaptation.



<h2 class="wp-block-heading" id="h-borrowed-toxin-for-defense">Borrowed toxin for defense</h2>



Researchers at the University of California, Berkeley, led by Noah Whiteman, have identified a bacterial gene that <a href="https://www.earth.com/news/fruit-flies-on-treadmills-video-shows-how-insects-walk-and-balance/" target="_blank" rel="noreferrer noopener">fruit flies</a> use to fend off parasitic wasps.



This gene encodes a toxin that damages the DNA of wasp eggs, preventing them from developing. 



According to Whiteman, the discovery provides a model for understanding how immune systems evolve, including our immune system, which also contains horizontally transferred genes. Whiteman.



The team previously showed that knocking out this gene in&nbsp;Drosophila ananassae&nbsp;resulted in nearly all fly larvae succumbing to wasp predation.



In their latest study, published in the journal Current Biology, they successfully inserted the toxin-encoding gene into&nbsp;Drosophila melanogaster, a different species of fruit fly. This made the genetically modified lab flies resistant to predation by parasitic wasps. 



The findings highlight the critical role of HGT in animal survival and adaptation.



<h2 class="wp-block-heading" id="h-strategies-of-fruit-flies-against-wasps">Strategies of fruit flies against wasps</h2>



"This shows that horizontal gene transfer is an under-appreciated way that rapid evolution happens in animals," said Rebecca Tarnopol, a <a href="https://www.berkeley.edu" target="_blank" rel="noreferrer noopener">UC Berkeley</a> doctoral student and first author of the study. 



While HGT is well-recognized in microbes, Tarnopol noted that it might occur more frequently in <a href="https://www.earth.com/news/insects-fruit-flies-smell-well-as-humans-with-much-less-nose-neurons/" target="_blank" rel="noreferrer noopener">insects</a> than previously thought.



The toxin gene, dubbed fusionB, originates from a bacteriophage - a virus that infects bacteria. This phage initially passed the gene to bacteria that lived inside aphids.



In turn, the bacteria used the gene to defend aphids against parasitic wasps. Flies, borrowing the same genetic tool, now use it to protect themselves from wasps, creating a fascinating chain of genetic borrowing across different species.



<h2 class="wp-block-heading" id="h-precision-in-gene-expression">Precision in gene expression</h2>



Expressing the toxin gene safely was a key challenge. When Tarnopol initially expressed the gene throughout the fly's body, all of the <a href="https://www.earth.com/news/flies-are-more-vulnerable-to-climate-change-than-bees/" target="_blank" rel="noreferrer noopener">flies</a> died.



However, targeting specific immune cells enabled the flies to utilize the toxin effectively without harming themselves. This delicate balance illustrates the complexities of HGT. 



"If the gene is expressed in the wrong tissue, the fly is going to die. But if it lands in a favorable location, it can confer an amazing advantage," noted Whiteman.



<h2 class="wp-block-heading" id="h-gene-transfer-and-immune-defenses">Gene transfer and immune defenses</h2>



The study reveals that horizontal gene transfer might drive immune defense evolution in animals. 



"It gives us a picture of a new kind of dynamism," said Whiteman, highlighting how even animals with innate immune systems can adapt rapidly by borrowing genes from rapidly-evolving microbes.



This discovery also has implications for human health. Understanding how genes are co-opted and shared could inform therapies to combat parasitic infections, cancer, or other diseases. 



By investigating how fruit flies utilize bacterial genes to defend against parasitic wasps, the researchers uncovered valuable insights into the evolutionary processes shaping immune systems in various species.



This research sheds light on the genetic mechanisms that animals may use to adapt and survive against evolving threats.



<h2 class="wp-block-heading" id="h-an-ingenious-strategy">An ingenious strategy </h2>



The fruit flies' ingenious borrowing of bacterial defenses exemplifies nature's resourcefulness against relentless wasps and other threats.



This remarkable work sheds light on the hidden role of horizontal gene transfer in animal evolution and offers a glimpse into potential applications for human health. 



"When you're a poor little fruit fly, borrowing genes from rapidly evolving bacteria and viruses is an ingenious strategy," Whiteman concluded.



The study is published in the journal <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(24)01638-5" target="_blank" rel="noreferrer noopener">Current Biology</a>.



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Fruit flies have a new weapon to defend against parasitic wasps

In the relentless battle between parasites and their hosts, nature...

The rugged landscape of Alaska often leaves people spellbound with its soaring peaks and dramatic valleys. 



Many geologists believe that these mountains and valleys are more than scenic wonders. Interestingly, the Denali Fault plays a critical role in shaping this awe-inspiring Alaskan terrain. Recent work has given a fresh perspective on how entire land masses may have drifted, collided, and fused, over long stretches of time, to form what we recognize today as the North American landscape.



<h2 class="wp-block-heading" id="h-the-denali-fault-in-alaska">The Denali Fault in Alaska</h2>



Scientists have debated how <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">ancient fragments</a> of the western margin of North America joined together. The Denali Fault, a <a href="https://earthobservatory.nasa.gov/features/denali" target="_blank" rel="noreferrer noopener">massive feature</a> that slices through Alaska, has been at the center of many investigations.



New <a href="https://pubs.geoscienceworld.org/gsa/geology/article-abstract/52/12/933/649182/Orogen-scale-inverted-metamorphism-during?redirectedFrom=fulltext" target="_blank" rel="noreferrer noopener">findings</a> suggest that three, seemingly separate geologic sites, spread along roughly 620 miles (1,000 kilometers), were once a smaller unit that signaled the final bonding of far-flung pieces of Earth's crust.



Geologists propose that these linked sites were torn apart again over millions of years.



<h2 class="wp-block-heading" id="h-unraveling-tectonic-mysteries">Unraveling tectonic mysteries</h2>



Experts have long focused on the northern <a href="https://www.researchgate.net/publication/329259890_The_Dynamic_History_of_220_Million_Years_of_Subduction_Below_Mexico_A_Correlation_Between_Slab_Geometry_and_Overriding_Plate_Deformation_Based_on_Geology_Paleomagnetism_and_Seismic_Tomography" target="_blank" rel="noreferrer noopener">North American Cordilleran margin</a>, which has been tectonically active for <a href="https://www.uvic.ca/science/seos/assets/docs/afgreadings13.pdf" target="_blank" rel="noreferrer noopener">over 200 million years</a>. Large fragments, known as exotic terranes, are present along the margin. They were once separate pieces of crust that occurred in locations far from the site where they now rest. 



<a href="https://www.researchgate.net/publication/240674082_Wrangellia-A_displaced_terrane_in_northwestern_North_America" target="_blank" rel="noreferrer noopener">Wrangellia</a> is among the biggest of these terranes; it was an oceanic plate that formed far away before docking with North America, tens of millions of years ago. Over time, complex strike-slip faults like the Denali Fault have shifted and displaced these <a href="https://www.earth.com/news/earths-crust-is-dripping-under-turkey/" target="_blank" rel="noreferrer noopener">bits of crust</a>, masking the full story of how they first fused to the continent.



“We’re starting to recognize those primary features involved in the stitching, or the suturing, of once-distant land masses to the North American plate,” said <a href="https://scholar.google.com/citations?user=Lrz_LL8AAAAJ&amp;hl=en&amp;oi=ao" target="_blank" rel="noreferrer noopener">Regan</a>, an associate professor at the University of Alaska Fairbanks' <a href="https://www.gi.alaska.edu/" target="_blank" rel="noreferrer noopener">Geophysical Institute</a> and the UAF College of Natural Science and Mathematics (<a href="https://www.uaf.edu/cnsm/" target="_blank" rel="noreferrer noopener">CNSM</a>). 



<h2 class="wp-block-heading" id="h-shared-tectonic-history-of-alaska-and-yukon">Shared tectonic history of Alaska and Yukon</h2>



A major clue in these findings is something called inverted metamorphism. 



Typically, deeper rocks show higher temperatures and pressures, while shallower rocks show lower ones. Sometimes the order reverses, and <a href="https://www.earth.com/news/mantle-heat-shaped-earths-crust-3-billion-years-ago/" target="_blank" rel="noreferrer noopener">rocks</a> formed in hotter conditions appear above the cooler layers.



According to researchers, this phenomenon appears in the Clearwater Mountains of Southcentral Alaska, the Kluane Lake area of Canada’s southwestern Yukon, and the Coast Mountains near Juneau. 



It became clear that all three of these independent, inverted metamorphic belts formed at the same time under similar conditions. Inverted metamorphic belts often point to <a href="https://pubs.usgs.gov/publication/70012246" target="_blank" rel="noreferrer noopener">intense thrusting events</a>, where layers of rock get shoved over one another in ways that defy the usual temperature and pressure patterns.



<h2 class="wp-block-heading" id="h-how-the-denali-fault-shook-things-up">How the Denali Fault shook things up</h2>



Before this <a href="https://pubs.geoscienceworld.org/gsa/geology/article-abstract/52/12/933/649182/Orogen-scale-inverted-metamorphism-during?redirectedFrom=fulltext" target="_blank" rel="noreferrer noopener">study</a>, some geologists suspected that each region had its own separate story. 



Regan’s analysis indicates that the three sites were once part of a single zone where the final merging of an ancient oceanic plate and the North American continent took place <a href="https://dggs.alaska.gov/pubs/id/29785" target="_blank" rel="noreferrer noopener">between 72 million and 56 million years ago</a>.



The Denali Fault came into play when post-collision shifting rearranged these pieces, scattering what had been one geologic feature across hundreds of miles. 



Researchers suggest that analyzing the movement along the fault reveals how these fractured pieces still fit together.



<h2 class="wp-block-heading" id="h-monazite-holds-the-key">Monazite holds the key</h2>



Monazite is at the core of identifying the shared history of these three sites. This mineral contains lanthanum, cerium, neodymium, and sometimes yttrium. “It is just the most special little mineral; it can participate in a lot of reactions, so we can use it as a way to track the mineralogical evolution of a rock,” explained Sean Regan. 



Specialists measure slight changes in <a href="https://pure.port.ac.uk/ws/portalfiles/portal/4085484/In_situ_LA_ICP_MS_dating_of_monazite_from_aluminous_gneisses_insights.pdf" target="_blank" rel="noreferrer noopener">monazite’s composition</a> to determine the timing and conditions of its formation.



<h2 class="wp-block-heading" id="h-denali-fault-and-earth-s-tectonic-activity">Denali Fault and Earth’s tectonic activity</h2>



Beyond their technical significance, these discoveries remind us that Earth’s surface is far from static. 



North America’s western margin has lived through episodes of oceanic plates, volcanic arcs, and shifted terrains that continue to shape the mountains and valleys seen today. Researchers see the Denali Fault as a record of long-distance transport of <a href="https://www.earth.com/news/claim-earth-has-six-continents-not-seven-north-america-europe-connected/" target="_blank" rel="noreferrer noopener">crustal fragments</a>, revealing the final act in the complicated docking of the Wrangellia Composite Terrane.



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



Many wonder how these findings will inform geological models of Alaska and Western Canada in future.



Geologists stress that further fieldwork, improved dating methods, and more collaborations are necessary to verify the timing and extent of major tectonic shifts.



Some plan to re-examine old mapping data or look at newly exposed <a href="https://www.earth.com/news/nasa-swot-satellite-mission-maps-earths-ocean-floors-from-space-in-stunning-detail/" target="_blank" rel="noreferrer noopener">rocks</a> for additional clues. Even small details, like determining a rock’s age down to the nearest million years, may one day yield a clearer history of ancient movements.



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Denali fault: Scientists finally learn how America's tallest mountain formed

The rugged landscape of Alaska often leaves people spellbound with...

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<a href="https://www.earth.com/news/meat-consumption-climate-change/">Climate change</a> has shown us just how much human activity can impact our planet, but did you know that we can also affect conditions in space too? Today’s Video of the Day comes from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> and features a look at how humans can influence space weather. 
It turns out that Cold War-era nuclear tests set off an unexpected chain reaction that affected the skies and power girds across the globe, reaching as far as our own satellites in space. 
The more we learn about how humans impact the planet and beyond, the better equipped we become to protect ourselves. How humans can influence space weather as shown above in video will show you Space weather storms can cause trouble on Earth. Strong storms can mess up radio signals, shut down electrical systems, and expose people to radiation. How does Space Weather affect Earth and Human Society? Although space weather forecasts are not normally featured on the evening news, space weather does impact life on Earth in many ways.
But the information it provides will help scientists understand how events on the Sun have the ability to disrupt Earth&#8217;s communications, overload power grids, present a hazard to astronauts, and affect weather patterns. We call this effect on Earth &#8220;space weather.&#8221;
  &#8212;
By <a href="mailto:rarnold@earth.com">Rory Arnold</a>, <a href="https://www.earth.com/staff">Earth.com</a>
Video Credit: <a href="https://www.nasa.gov/goddard">NASA Goddard</a>