Today's Image of the Day from the European Space Agency features NGC 6744 - a large, barred spiral galaxy located approximately 30 million light-years away in the constellation Pavo.&nbsp;



The galaxy is often considered a close analog to the <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> due to its similar structure and size, spanning about 175,000 light-years across.&nbsp;



<h2 class="wp-block-heading" id="h-euclid-space-mission-nbsp">Euclid space mission&nbsp;</h2>



The image was captured by the <a href="https://www.esa.int/Science_Exploration/Space_Science/Euclid" target="_blank" rel="noreferrer noopener">Euclid</a> space telescope. NGC 6744 stands out as a prime example of the galaxies currently forming the majority of stars in the nearby universe, making it an ideal subject for study with the Euclid mission.&nbsp;



Euclid’s extensive field-of-view allows it to capture the entire galaxy, showcasing not only its large-scale spiral structure but also revealing intricate details on smaller scales across various wavelengths. These details include feather-like dust lanes, known as “spurs,” emerging from the spiral arms.



<h2 class="wp-block-heading" id="h-star-formation-in-ngc-6744">Star formation in NGC 6744</h2>



Euclid's observations enable scientists to count individual stars within NGC 6744, trace the distribution of stars and dust throughout the galaxy, and map the dust associated with the gas that fuels the development of new stars. 



<a href="https://www.earth.com/news/baby-stars-release-sneezes-of-gas-and-dust-as-they-develop/" target="_blank" rel="noreferrer noopener">Star formation</a> is a key process in the growth of galaxies, making these studies crucial for understanding galaxy evolution.



Researchers are utilizing Euclid’s data to explore the relationship between dust, gas, and star formation; to map the distribution of different stellar populations and identify regions of active star formation; and to investigate the underlying physics of spiral galaxy structures.&nbsp;



Spiral arms play a significant role in star formation by compressing gas, yet the precise mechanisms behind this process are still unclear. The presence of “spurs” along NGC 6744’s spiral arms offers valuable insights into the dynamics of star formation within these structures.



<h2 class="wp-block-heading" id="h-discovering-new-dwarf-galaxies-nbsp">Discovering new dwarf galaxies&nbsp;</h2>



Additionally, Euclid's dataset will help scientists identify clusters of old stars (globular clusters) and discover new dwarf galaxies around NGC 6744. Remarkably, Euclid has already identified a new dwarf satellite galaxy of NGC 6744 - a surprising discovery given that the galaxy has been studied extensively.



With Euclid’s detailed observations, scientists are gaining a deeper understanding of the processes shaping galaxies, providing essential clues to the evolution and appearance of the <a href="https://www.earth.com/news/universes-expansion-rate-hubble-tension-puzzles-astronomers/" target="_blank" rel="noreferrer noopener">universe</a>.



<h2 class="wp-block-heading" id="h-more-about-ngc-6744">More about NGC 6744</h2>



NGC 6744's disk is rich in star-forming regions and contains numerous young, bright blue stars. The galaxy's nucleus is slightly elongated and has a bar structure, which influences the motion of the stars and gas within it.&nbsp;



The spiral arms of NGC 6744 are well-defined and extend outward, wrapping around the central bar. Additionally, NGC 6744 has a smaller companion galaxy, NGC 6744A, which is interacting with it, adding to the complexity and interest of this distant system.&nbsp;



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



<a href="https://www.earth.com/news/the-mesmerizing-beauty-of-spiral-galaxies/" target="_blank" rel="noreferrer noopener">Spiral galaxies</a> are one of the most common types of galaxies in the universe, characterized by their distinct, spiral-shaped structure.&nbsp;



The galaxies typically consist of a flat, rotating disk containing stars, gas, and dust, along with a central concentration of stars known as the bulge. This bulge is often surrounded by a halo of older stars.&nbsp;



The spiral arms, which extend from the central bulge, are regions of active star formation and are rich in young, hot stars, giving them a bright, bluish appearance.&nbsp;



These arms are also sites where interstellar gas and dust are concentrated, leading to the formation of new stars.&nbsp;



Spiral galaxies are classified into different types based on the tightness of their spirals and the size of their central bulge, with classifications ranging from tightly wound arms in Sa galaxies to more loosely wound arms in Sc galaxies. The <a href="https://www.earth.com/news/large-amount-of-dark-matter-may-be-missing-from-the-milky-way/" target="_blank" rel="noreferrer noopener">Milky Way</a>, our home galaxy, is a prime example of a spiral galaxy.



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



Pavo, which means "peacock" in Latin, is a constellation in the southern sky. It was named by the Dutch astronomer Petrus Plancius in the late 16th century, based on observations made during the Dutch explorations of the southern hemisphere. 



Pavo is one of the 12 constellations created by Plancius from the records of explorers Pieter Dirkszoon Keyser and Frederick de Houtman. 



The constellation is known for its distinctive shape, resembling a peacock with a long, curved tail. Pavo is not visible from most of the northern hemisphere, but it can be seen from the southern hemisphere, particularly during the winter months.



The constellation contains several interesting celestial objects, including the star Peacock, also known as Alpha Pavonis, which is the brightest star in the constellation. This star is a blue-white subgiant located about 179 light-years from Earth.



Image Credit: <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>/Euclid/Euclid Consortium/NASA&nbsp;



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Spiral galaxy NGC 6744 in the constellation Pavo

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

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 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...

Cities around the globe are taking steps to shield residents from the dangers of tailpipe pollution. According to the Environmental Protection Agency (EPA), traffic remains a leading source of greenhouse gas emissions in the United States. Residents of neighborhoods with high truck activity face increased exposure to pollutants that can worsen breathing troubles. 



Recent findings have tied heavy-duty vehicle pollution to serious health problems. A growing number of <a href="https://iopscience.iop.org/article/10.1088/2752-5309/ad9f95" target="_blank" rel="noreferrer noopener">studies</a> are exploring the potential of using electricity over diesel or gasoline in big rigs and delivery trucks.



<h2 class="wp-block-heading" id="h-traffic-pollution-and-health-expenses">Traffic pollution and health expenses </h2>



Over the years, city roads have seen a flood of medium- and heavy-duty vehicles crisscrossing tight corridors around shipping terminals and industrial areas. These trucks emit fine particulate matter and <a href="https://www.earth.com/news/gas-stoves-emit-unsafe-levels-of-nitrogen-dioxide/" target="_blank" rel="noreferrer noopener">nitrogen dioxide</a>, which have been linked to lung irritations and rising health expenses. They also generate smog-forming pollutants that can lead to visibility concerns in urban environments.



Brian Naess is a GIS analyst and lecturer at the <a href="https://ie.unc.edu/" target="_blank" rel="noreferrer noopener">UNC Institute for the Environment</a>. His team evaluated the air quality and health benefits of electrifying medium- and heavy-duty vehicles (MHDEVs) in New York City, focusing on disparities across neighborhoods and population groups.



The <a href="https://iopscience.iop.org/article/10.1088/2752-5309/ad9f95" target="_blank" rel="noreferrer noopener">research</a> points to a potential $2.4 billion decrease in health-related expenses if New York achieves a broad transition to electric trucks by 2040.&nbsp;



<h2 class="wp-block-heading" id="h-the-electrification-push">The electrification push</h2>



Electric trucks rely on rechargeable batteries rather than burning fuels that emit carbon dioxide and other pollutants. 



Some city fleets have already moved to battery-powered vans for deliveries.



Researchers see this move as a step toward reducing greenhouse gas emissions and trimming <a href="https://www.earth.com/news/electric-vehicles-could-save-billions-in-health-care-costs-by-2050/" target="_blank" rel="noreferrer noopener">public health costs</a>.



<h2 class="wp-block-heading" id="h-electric-trucks-and-no2-emissions">Electric trucks and NO2 emissions</h2>



Nitrogen dioxide, formed when fossil fuels burn at high temperatures, is a major contributor to respiratory stress. Multiple investigations have shown that targeted interventions to slash NO2 can reduce <a href="https://www.earth.com/news/first-new-asthma-treatment-in-50-years-offers-hope-for-millions/" target="_blank" rel="noreferrer noopener">asthma attacks</a>.



Scientists <a href="https://pubmed.ncbi.nlm.nih.gov/38499224/" target="_blank" rel="noreferrer noopener">conducted</a> a literature search of MEDLINE, Embase, Global Health, CINAHL, Scopus, and Environmental Science Collection databases. The analysis was focused on articles published between January 1990 and January 2024.&nbsp;



The experts found that almost every study reported evidence of positive health impacts from transitioning to electric or hybrid electric vehicles 



Some findings suggested that benefits linked to reducing NO2 emissions can form the bulk of health gains in an electrification scenario.



<h2 class="wp-block-heading" id="h-environmental-justice-concerns">Environmental justice concerns </h2>



Many areas with mostly Black or Hispanic households sit near busy roads. This has led to air pollution concerns and higher rates of respiratory issues.



A 2023 report highlighted the significant benefits of transitioning to electric vehicles (EVs) under New York’s Climate Leadership and Community Protection Act (CLCPA). The team found overwhelming evidence that widespread EV adoption, especially in medium- and heavy-duty vehicles, could dramatically reduce greenhouse gas emissions and improve air quality. These changes would directly benefit disadvantaged communities that have historically faced higher <a href="https://www.earth.com/news/u-s-air-pollution-levels-have-dropped-but-not-for-everyone/" target="_blank" rel="noreferrer noopener">pollution levels</a>, addressing long-standing environmental justice concerns.&nbsp;



<h2 class="wp-block-heading" id="h-cost-of-switching-to-electric-trucks">Cost of switching to electric trucks</h2>



Shifting city trucks to <a href="https://www.earth.com/news/the-future-is-electric-epa-sets-strictest-ever-vehicle-emission-rules/" target="_blank" rel="noreferrer noopener">electric power</a> demands heavy investment in battery systems and charging equipment. 



Fleets must consider the startup costs of new trucks, but the drop in fuel and maintenance expenses appears to help offset the price. 



Trucks that operate on electric power can also reduce greenhouse gases and smog contributors, which <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC7567144/" target="_blank" rel="noreferrer noopener">correlates</a> with fewer doctor visits.



<h2 class="wp-block-heading" id="h-modeling-tools-and-community-monitoring">Modeling tools and community monitoring</h2>



Officials in New York have used modeling tools to calculate how local traffic choices may affect air pollution levels. 



One advanced platform, known as the <a href="https://pubmed.ncbi.nlm.nih.gov/35475336/" target="_blank" rel="noreferrer noopener">ZIP Code-Level Air Pollution Policy Assessment</a> (ZAPPA), merges data from environmental agencies and community monitoring stations.



Another system, the<a href="https://www.epa.gov/cobra" target="_blank" rel="noreferrer noopener"> Co-Benefits Risk Assessment Health Impacts Screening and Mapping Tool </a>(COBRA), offers estimates of health outcomes in specific areas. 



These models identify places where trucks produce the worst air quality issues and predict how electrification might help.



<h2 class="wp-block-heading" id="h-the-potential-of-electric-vehicles">The potential of electric vehicles</h2>



Research from multiple sources points to the potential for electric cars to reduce pediatric asthma and lower hospital admissions. 



More city governments are pushing rules and incentives, ranging from rebates on electric truck purchases to installing more charging stations.



Planners see electric trucks as a chance to meet climate goals while bringing relief to families who struggle with healthcare costs. This movement could transform roads into cleaner routes for everyone.



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Public health and environmental justice: The push for electric trucks in cities

Cities around the globe are taking steps to shield residents...

Paleontologists have made a remarkable discovery that bridges a gap of 150 million years. Their new study has uncovered nearly 50 hidden relatives of Pterodactylus, the first pterosaur ever discovered.



This fossil find from the <a href="https://le.ac.uk/" target="_blank" rel="noreferrer noopener">University of Leicester</a> allows scientists to piece together the life story of this ancient flying reptile, from its earliest days to adulthood.



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



These fascinating flying reptiles weren't actually dinosaurs, but rather a separate group of flying reptiles that first appeared around 230 million years ago during the Triassic period. 



Unlike birds or bats, pterosaurs had a unique wing structure formed by a membrane of skin and muscle that stretched from an elongated fourth finger to their body. This created a lightweight and flexible flying apparatus that allowed them to soar and glide.



Different pterosaur species came in an astonishing range of sizes, from tiny creatures the size of sparrows to massive pterosaurs with wingspans around 33 feet wide. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/Pterodactylus_growth-stages_illustration_ULeicester_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/12/Pterodactylus_growth-stages_illustration_ULeicester_1s.webp" alt="Growth stages of Pterodactylus. From tiny &quot;flaplings&quot; no larger than a sparrow, most known specimens represent 'teenagers' comparable in size to a pigeon. Fully grown individuals boasted impressive wingspans exceeding 1 meter. Unlike birds, which must grow before achieving flight, even the smallest Pterodactylus were capable of flight from an early age. Credit: University of Leicester" class="wp-image-1954862"/></a><figcaption class="wp-element-caption">Growth stages of Pterodactylus. From tiny "flaplings" no larger than a sparrow, most known specimens represent 'teenagers' comparable in size to a pigeon. Fully grown individuals boasted impressive wingspans exceeding 1 meter. Unlike birds, which must grow before achieving flight, even the smallest Pterodactylus were capable of flight from an early age. Credit: University of Leicester</figcaption></figure>



Some had long, spear-like beaks perfect for fishing, while others sported elaborate head crests that might have been used for display, communication, or even temperature regulation. 



Their bones were incredibly lightweight and hollow, similar to modern bird bones, which helped them achieve flight with minimal energy expenditure.



Pterosaurs were incredibly successful and adaptable creatures that survived for an impressive 160 million years before finally going extinct along with the dinosaurs during the catastrophic asteroid impact at the end of the Cretaceous period. 



Their fossils have been discovered on every continent, revealing that they occupied diverse environments from coastal regions to inland areas.



<h2 class="wp-block-heading" id="h-first-pterosaur-discovery">First pterosaur discovery</h2>



Almost 250 years ago, a fossil unearthed in a Bavarian quarry introduced the world to <a href="https://www.earth.com/news/pterosaur-new-species-named-abfab-had-wings-wide-as-car/" target="_blank" rel="noreferrer noopener">pterosaurs</a>. 



This fossil, named&nbsp;Pterodactylus, offered the first glimpse into the Mesozoic skies, where these creatures soared above the dinosaurs.



Though the first specimen was modest in size - comparable to a turtle dove - it revolutionized our understanding of prehistoric life and showcased the extraordinary <a href="https://www.earth.com/news/pterosaurs-took-flight-millions-of-years-before-birds/" target="_blank" rel="noreferrer noopener">diversity of flying reptiles</a>.



Over time, however,&nbsp;Pterodactylus&nbsp;faded from public attention, overshadowed by its larger and flashier relatives, such as&nbsp;Pteranodon&nbsp;and&nbsp;Quetzalcoatlus. 



Yet, among scientists,&nbsp;the Pterodactylus genus remained a vital subject of study that played a central role in shaping our understanding of pterosaur anatomy, flight, diet, and growth.



<h2 class="wp-block-heading" id="h-finding-pterodactylus-family">Finding Pterodactylus family</h2>



Despite its significance, confusion has long surrounded&nbsp;Pterodactylus. 



Fossils attributed to this genus were often mixed with other species, making it challenging to determine which truly belonged to&nbsp;Pterodactylus. This <a href="https://www.earth.com/news/new-fossil-fills-crucial-gap-in-pterosaur-evolution/" target="_blank" rel="noreferrer noopener">ambiguity</a> persisted for centuries - until now.



Using UV fluorescence, paleontologists Robert Smyth and Dr. Dave Unwin from the <a href="https://le.ac.uk" target="_blank" rel="noreferrer noopener">University of Leicester</a> conducted a meticulous analysis of&nbsp;Pterodactylus&nbsp;fossils housed in museums across Europe. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/Pterodactylus_fossil_UV-light_ULeicester_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/12/Pterodactylus_fossil_UV-light_ULeicester_1s.webp" alt="UV photography of Pterodactylus. Ultraviolet light reveals remarkable details of the fossil invisible under normal lighting. This famous specimen showcases preserved soft tissues, including the delicate wing membranes, which fluoresce vividly under UV illumination. Credit: University of Leicester" class="wp-image-1954860"/></a><figcaption class="wp-element-caption">UV photography of Pterodactylus. Ultraviolet light reveals remarkable details of the fossil invisible under normal lighting. This famous specimen showcases preserved soft tissues, including the delicate wing membranes, which fluoresce vividly under UV illumination. Credit: University of Leicester</figcaption></figure>



By shining powerful UV light on fossilized bones, they illuminated previously invisible features that distinguish the&nbsp;Pterodactylus&nbsp;family from other pterosaurs. Their work revealed dozens of misclassified fossils, including over 40 specimens that were reidentified as&nbsp;Pterodactylus.



“By examining lots of fossils in collections across Europe, we were able to reidentify more than forty specimens as&nbsp;Pterodactylus,” said lead author Robert Smyth. 



“UV stimulated fluorescence is astonishing in the amount of detail it can reveal. Features that were once hidden were glowing in plain sight.”



<h2 class="wp-block-heading" id="h-new-face-of-nbsp-pterodactylus">New face of&nbsp;Pterodactylus</h2>



This discovery has profoundly altered the scientific understanding of&nbsp;the genus Pterodactylus. Previously thought to be a rare find, nearly 50 specimens have now been confirmed.



This expanded collection allows researchers to construct a complete and detailed skeletal anatomy of this <a href="https://www.earth.com/news/cracking-the-code-of-pterosaur-flight-soaring-vs-flapping/" target="_blank" rel="noreferrer noopener">pivotal pterosaur</a>. 



Remarkably, soft tissues are preserved in over 20 of the specimens, which provides unprecedented insights into a range of features.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/Pterodactylus_comparison-relative_fossil_UV-light_ULeicester_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/12/Pterodactylus_comparison-relative_fossil_UV-light_ULeicester_1s.webp" alt="Family resemblance. This larger specimen is slightly jumbled, but it still reveals many important details, including the anatomy of the hands and feet, which have been found to be highly diagnostic features. This allows us to distinguish Pterodactylus from other closely related pterosaurs. Credit: University of Leicester" class="wp-image-1954857"/></a><figcaption class="wp-element-caption">Family resemblance. This larger specimen is slightly jumbled, but it still reveals many important details, including the anatomy of the hands and feet, which have been found to be highly diagnostic features. This allows us to distinguish Pterodactylus from other closely related pterosaurs. Credit: University of Leicester</figcaption></figure>



“We can now construct a complete and highly detailed skeletal anatomy for this key pterosaur,” explained co-author Dr. Dave Unwin. “Soft tissues are fossilised in more than twenty examples so we can also reconstruct head crests, body shape, foot webs, and even the wings.”



The result is akin to a family portrait, showcasing Pterodactylus at every stage of its life. The smallest hatchlings, endearingly called “flaplings,” were robin-sized. 



These grew into “teenage” forms before reaching adulthood, where they boasted raven-sized bodies and wingspans of up to ten times their body length.



<h2 class="wp-block-heading" id="h-a-revolutionary-technique">A revolutionary technique</h2>



The study highlights the transformative potential of UV fluorescence in paleontology. 



While the technique is well-known, the combination of advanced light sources and a systematic approach has yielded groundbreaking results in this case.



“UV stimulated fluorescence is a well-known technique,” Dr. Unwin noted. 



“But the difference in this case is that we have been able to combine new, high-quality light sources with a systematic "catch-all" approach, and it's going to have a revolutionary impact on our understanding of pterosaurs.”



<h2 class="wp-block-heading" id="h-pterodactylus-family-and-future-study">Pterodactylus family and future study</h2>



This discovery not only redefines&nbsp;Pterodactylus&nbsp;but also highlights the value of revisiting and reexamining existing collections of fossils.



With nearly 50 examples now identified, researchers have an unprecedented opportunity to explore the life history of one of the most important pterosaurs. 



From its early days as a tiny flapling to its commanding presence in the skies,&nbsp;the Pterodactylus&nbsp;fossils provide a vivid window into the Mesozoic era.



As families come together this festive season, paleontologists celebrate their own remarkable reunion - a long-lost family, brought back to light after 150 million years.



The study is published in the <a href="https://www.tandfonline.com/doi/full/10.1080/14772019.2024.2421845" target="_blank" rel="noreferrer noopener">Journal of Systematic Palaeontology</a>. 



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Pterodactylus: New pterosaur family members discovered that lived 150 million years ago

Paleontologists have made a remarkable discovery that bridges a gap...

Vesta,Asteroid,(elements,Of,This,Image,Furnished,By,Nasa)

The asteroid belt is no stranger to cosmic collisions. Many of its objects bear scars and craters from countless strikes over billions of years, such as the asteroid named Vesta. 



But when NASA’s Dawn spacecraft visited the giant asteroid Vesta, it glimpsed more than pockmarks and gouges -- it discovered intriguing channels on the rocky surface.



The deep channels on Vesta looked suspiciously like gullies carved by liquid flows, which seemed rather unlikely on an airless body in the vacuum of space.



These gullies challenged the assumptions of how liquids might appear on such a rugged, atmosphere-free world.



<h2 class="wp-block-heading" id="h-hidden-channels-on-asteroid-vesta">Hidden channels on asteroid Vesta</h2>



Vesta’s unusual channels stirred interest in whether there might be hidden pockets of ice below the surface. <a href="https://iopscience.iop.org/article/10.3847/PSJ/ad696a" target="_blank" rel="noreferrer noopener">Researchers</a> wondered how any liquid could last long enough to carve gullies instead of evaporating in an instant from the asteroid's surface. This puzzle prompted a team to conduct experiments that mimic the conditions on Vesta, to see what might be at work beneath the <a href="https://www.earth.com/news/most-meteorites-can-be-traced-to-three-asteroid-families/" target="_blank" rel="noreferrer noopener">asteroid’</a>s crater-pocked exterior.



<h2 class="wp-block-heading" id="h-what-made-vesta-s-channels">What made Vesta’s channels?</h2>



Asteroids the size of Vesta rank among the largest members of the <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/asteroid-belts" target="_blank" rel="noreferrer noopener">asteroid belt</a> between Mars and Jupiter. 



Although the surface has been pummeled by impacts, scientists suspected that some small, deeply buried ice deposits might exist within Vesta. A NASA-funded project took a closer look at how meteoroid <a href="https://www.earth.com/news/ocean-world-ceres-near-mars-is-full-of-organic-matter-that-may-support-life/" target="_blank" rel="noreferrer noopener">impacts</a> could unearth these concealed layers and release liquid water. Many researchers had argued that any water would vanish quickly in space. But new lab findings showed that saline solutions might linger long enough to form the winding channels observed in high-resolution images.



“Not only do impacts trigger a flow of liquid on the surface, the liquids are active long enough to create specific surface features,” said <a href="https://scienceandtechnology.jpl.nasa.gov/jennifer-scully" target="_blank" rel="noreferrer noopener">Jennifer Scully</a> of NASA’s <a href="https://www.jpl.nasa.gov/" target="_blank" rel="noreferrer noopener">Jet Propulsion Laboratory</a> in Southern California who explained the significance of these results. This work provides a clue to how short-lived fluids might appear on <a href="https://www.earth.com/news/earth-has-lost-its-mini-moon-2024-pt5-may-have-come-from-our-main-moon/" target="_blank" rel="noreferrer noopener">worlds</a> once deemed too harsh for liquid water.



<h2 class="wp-block-heading" id="h-moving-into-the-lab">Moving into the lab</h2>



Shortly after the discovery of channels on Vesta, the research team, led by <a href="https://www.swri.org/industry/space-science/planetary-science-research-staff" target="_blank" rel="noreferrer noopener">Michael J. Poston</a> of the Southwest Research Institute in San Antonio, set up a series of simulations to re-create post-impact conditions. They relied on a specialized facility at NASA’s Jet Propulsion Laboratory called the Dirty Under-vacuum Simulation Testbed for Icy Environments (<a href="https://www.jpl.nasa.gov/images/pia26405-a-look-inside-jpls-dustie-planetary-simulation-chamber/" target="_blank" rel="noreferrer noopener">DUSTIE</a>). 



Inside this chamber, they subjected small liquid samples to low-pressure environments that match those on Vesta’s surface. Under these near-vacuum conditions, pure water froze almost instantly. But briny water, which is rich in sodium chloride, took at least an hour to freeze.



That extra time can explain how curvy gullies might form. The experiments proved that salt plays an important role in keeping water liquid, even under conditions that usually turn plain water to ice right away. Poston noted that if the channels carved by these brines on Vesta were a few yards deep, the liquid phase would persist even longer. 



Their study described how this freezing delay could cause fluid to travel and create <a href="https://www.sciencedirect.com/science/article/abs/pii/S0012821X14007572?via%3Dihub" target="_blank" rel="noreferrer noopener">gullies</a> before it finally solidified.



<h2 class="wp-block-heading" id="h-salt-s-unexpected-impact-and-hidden-ice-below">Salt’s unexpected impact and hidden ice below</h2>



Ice and salt often coexist on other airless bodies in the solar system. 



Scientists studying <a href="https://eyes.nasa.gov/apps/orrery/#/1_ceres" target="_blank" rel="noreferrer noopener">Ceres</a>, another object visited by the <a href="https://science.nasa.gov/mission/dawn/" target="_blank" rel="noreferrer noopener">Dawn spacecraft</a>, found abundant salt deposits near the surface. 



Similar processes might occur on Vesta, with hidden ice deposits that melt upon impact and release salty fluids that are capable of flowing.



<h2 class="wp-block-heading" id="h-why-should-we-care-about-asteroid-vesta">Why should we care about asteroid Vesta?</h2>



While direct evidence of ice on Vesta is still unconfirmed, researchers continue to analyze crater walls and gullies, looking for hints of exposed water-bearing minerals. 



If more ice deposits are detected, it would further support the idea that these <a href="https://www.earth.com/news/ceres-largest-asteroid-in-our-solar-system-used-to-be-an-ancient-ocean-planet/" target="_blank" rel="noreferrer noopener">asteroid surfaces</a> hide unexpected moisture beneath the dusty exterior.



Many experts highlight how this discovery of Vesta's channels ties in with other research on planetary bodies beyond Earth. 



Salt-rich flows have also been proposed to explain active gullies on Mars, where channels can appear seasonally as temperatures shift. Although the Red Planet has a thin atmosphere, brine might remain stable for short intervals in ways that resemble the results of the Vesta experiments.



Similar processes have been hypothesized for other airless worlds, fueling further curiosity about how widespread water could be in these unexpected places.



<h2 class="wp-block-heading" id="h-finding-water-in-the-asteroid-belt">Finding water in the asteroid belt</h2>



The Dawn mission provided valuable insight into the <a href="https://www.jpl.nasa.gov/news/mystery-solved-bright-areas-on-ceres-come-from-salty-water-below/" target="_blank" rel="noreferrer noopener">composition of Vesta</a> and Ceres, and the history of these objects. Observations of brine activity on Ceres prompted a rethinking of the asteroid belt’s arid reputation. If subsurface ices can be heated by impacts, short bursts of fluid flows might be more common than once assumed. The new experiments open a door for further study of how these liquids behave and how long they can remain stable in harsh, vacuum conditions.



Some see these lab results as a foundation for understanding what future spacecraft might find on icy asteroids or even distant moons. 



Asteroid Vesta's channels provide a key example and suggest that if other objects harbor briny fluids, they too might form channels when <a href="https://www.earth.com/news/nasa-test-simulation-shows-earth-not-prepared-prevent-large-asteroid-strike/" target="_blank" rel="noreferrer noopener">struck by meteoroids</a>.



Although quickly frozen, the liquid can still carve paths before turning to ice. This finding adds another piece to the puzzle of solar system evolution and the hidden chemistry that shapes so many distant worlds.



The research findings were published in <a href="https://iopscience.iop.org/article/10.3847/PSJ/ad696a">The Planetary Science Journal</a>.



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Asteroid Vesta found to have channels that look like water-made gullies

The asteroid belt is no stranger to cosmic collisions. Many...

<div class="vdb_player vdb_591c9e3c9efa894c3c6e150b58d96b98cd4fed198a0d2a49">
</div>

Today’s Video of the Day comes from the <a href="https://www.acs.org/">American Chemical Society’s</a> Reactions series and features a look at the science behind fireworks.
The clip is hosted by John Conkling, Adjunct Professor of Chemistry at <a href="https://www.washcoll.edu/">Washington College</a> and author of the book Chemistry of Pyrotechnics.
“Everything you see in a fireworks display is chemistry in action,” says Conkling. “The colors are all produced by very specific chemical mixtures that produce beautiful color <a href="https://www.earth.com/image/oil-fires-qayyarah-iraq/">flames</a>. The sparks are small pieces of fuel that continue to burn in air. Without chemistry, you couldn’t have the burning mixtures, and without the burning mixtures, you wouldn’t have fireworks.
&#8212;
By <a href="mailto:rarnold@earth.com">Rory Arnold</a>, <a href="https://www.earth.com/staff">Earth.com</a>
Source: <a href="https://www.youtube.com/watch?v=nPHegSulI_M">American Chemical Society</a>

The science behind fireworks