Today's Image of the Day from the European Space Agency features the Cat's Eye Nebula (NGC 6543), located about 3,300 light-years from Earth in the constellation Draco.&nbsp;



The nebula's name comes from its eye-like appearance when viewed through a telescope. This particular image, which reveals the <a href="https://www.earth.com/news/horsehead-nebula-webb-telescope-captured-unprecedented-detail/" target="_blank" rel="noreferrer noopener">nebula</a> in stunning detail, was captured by the NASA/ESA Hubble Space Telescope.



<h2 class="wp-block-heading" id="h-planetary-nebulae-nbsp">Planetary nebulae&nbsp;</h2>



According to ESA, the Cat's Eye Nebula is one of the most complex planetary nebulae that has ever been discovered.



“A planetary nebula forms when Sun-like stars gently eject their outer gaseous layers to form bright nebulae with amazing twisted shapes," explained <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



"Until recently, it was thought that shells around planetary nebulae were a rare phenomenon. However, astronomers have instead shown that these rings are likely to be the rule rather than the exception."



<h2 class="wp-block-heading" id="h-appearance-of-the-cat-s-eye-nebula-nbsp">Appearance of the Cat's Eye Nebula&nbsp;</h2>



The central focus of the Cat's Eye is a hot, dying star that has shed its outer layers to form the <a href="https://www.earth.com/news/dragons-egg-nebula-is-a-truly-stunning-sight-to-behold/" target="_blank" rel="noreferrer noopener">nebula</a>. It is surrounded by concentric gas shells, jets of high-speed gas, and unusual shock-induced knots of gas.



“Although the rings may be the key to explaining the final ‘gasp’ of the dying central star, the mystery behind the Cat’s Eye Nebula’s nested ‘Russian doll’ structure remains largely unsolved,” noted ESA.



<h2 class="wp-block-heading" id="h-rings-around-the-cat-s-eye">Rings around the Cat’s Eye</h2>



“This image, taken with Hubble's Advanced Camera for Surveys (ACS), reveals the full pattern of eleven or more concentric rings, or shells, around the Cat’s Eye. Each ‘ring’ is actually the edge of a spherical bubble seen projected onto the sky - which is why it appears bright along its outer edge.”



According to ESA, observations suggest that the star ejected its mass in a series of pulses at 1,500-year intervals. “These convulsions created dust shells that each contains as much mass as all of the planets in our solar system combined.”



Several explanations have been proposed for this phenomenon, including cycles of magnetic activity similar to our Sun's sunspot cycle, the influence of companion stars orbiting the <a href="https://www.earth.com/news/dying-stars-may-be-a-source-of-gravitational-waves/" target="_blank" rel="noreferrer noopener">dying star</a>, or stellar pulsations.&nbsp;



Another theory suggests that the material is ejected smoothly from the star, with the rings forming later due to the creation of waves in the outflowing material.



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



<a href="https://www.earth.com/news/extrasolar-ocean-planet-discovered-in-the-draco-constellation/" target="_blank" rel="noreferrer noopener">Draco</a> is a constellation in the northern sky that represents a dragon. It's one of the largest constellations, winding between the Big and Little Dippers.&nbsp;



In Greek mythology, Draco is often identified as the dragon Ladon, who guarded the golden apples in the garden of the Hesperides.



Draco is a circumpolar constellation for most northern hemisphere observers, meaning it never sets below the horizon and can be seen all year round.



<h2 class="wp-block-heading" id="h-famous-planetary-nebulae">Famous planetary nebulae </h2>



Planetary nebulae are some of the most beautiful and intriguing objects in the universe.&nbsp;



One of the most famous is the Ring Nebula, or M57, located in the constellation Lyra. This nebula is renowned for its nearly perfect ring shape, which is the result of a dying star shedding its outer layers.&nbsp;



Another well-known planetary nebula is the Helix Nebula, or NGC 7293, often referred to as the "Eye of God" due to its eye-like appearance. The Helix Nebula is one of the closest planetary nebulae to Earth, making it a popular target for amateur astronomers.&nbsp;



The Dumbbell Nebula, or M27, in the constellation Vulpecula, is another striking example. It is named for its resemblance to a dumbbell and is notable for being the first planetary nebula ever discovered, by Charles Messier in 1764.&nbsp;



The Butterfly Nebula, or NGC 6302, is located in the constellation Scorpius. Its name comes from its distinctive bipolar structure, resembling the wings of a butterfly. The nebula's central star is one of the hottest known, with a surface temperature of around 250,000 degrees Celsius.&nbsp;



The Eskimo Nebula, or NGC 2392, in the constellation Gemini, is known for its resemblance to a face surrounded by a fur parka, which gives it its name. Its intricate structure, including filaments and bubble-like shapes, makes it a fascinating object of study. 



These nebulae not only captivate us with their beauty but also provide valuable insights into the life cycles of stars and the processes that shape our galaxy.



Image Credit: NASA/ESA Hubble Space Telescope



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Cat's Eye Nebula in the constellation Draco

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

Today's Image of the Day from the European Space Agency features a Copernicus Sentinel-2 photograph of South Georgia, a remote and rugged island located in the southern Atlantic Ocean. 



"Linked with the South Sandwich Islands to form a British Overseas Territory, this southern Atlantic island is a haven for a vast array of wildlife," said <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



"Around five million seals call the islands home, as well as 65 million birds of 30 different species. Migrating whales and various fish species populate the surrounding waters and there is a large penguin population."



<h2 class="wp-block-heading" id="h-climate-and-wildlife-of-south-georgia">Climate and wildlife of South Georgia </h2>



The island is dominated by mountains, glaciers, and fjords. Its highest peak, Mount Paget, rises to 2,935 meters, making it one of the tallest in the region.



South Georgia’s location within the Antarctic Convergence gives it a cold, maritime climate. Although not part of the Antarctic Treaty System, its environment and <a href="https://www.earth.com/news/conservation-efforts-are-not-enough-to-save-antarctic-wildlife/" target="_blank" rel="noreferrer noopener">wildlife</a> are closely linked to Antarctica. 



The island is home to vast colonies of penguins, seals, and seabirds. The surrounding waters are rich with krill, providing an abundant food source for marine life.



<h2 class="wp-block-heading" id="h-penguins-adapted-to-harsh-environments">Penguins adapted to harsh environments </h2>



The most notable species found here are the king penguins, which are the second-largest penguin species in the world. South Georgia also hosts large populations of <a href="https://www.earth.com/news/what-makes-the-gentoo-penguin-the-worlds-fastest-swimming-bird/" target="_blank" rel="noreferrer noopener">gentoo</a> and macaroni penguins. 



The island's harsh climate, characterized by strong winds, snow, and cold temperatures, makes it a tough environment, but the penguins have adapted well. 



Their colonies - some of which number in the hundreds of thousands - can be found along the island's rugged coasts and beaches. 



The island’s isolation, combined with its plentiful food supply, makes it a critical breeding ground for these penguins.



<h2 class="wp-block-heading" id="h-history-of-south-georgia">History of South Georgia </h2>



The island has a history of exploration and exploitation. Captain James Cook first claimed South Georgia for Britain in 1775. 



During the late 19th and early 20th centuries, it became a hub for the <a href="https://www.earth.com/news/echoes-of-the-past-whalings-long-term-impact-on-genetic-diversity/" target="_blank" rel="noreferrer noopener">whaling</a> industry, with stations like Grytviken serving as operational centers. These stations have since been abandoned, and the island is now a haven for scientific research and ecotourism.



South Georgia is also notable for its role in Ernest Shackleton’s famed Endurance expedition. His crew reached the island in 1916 after an extraordinary open-boat journey from Elephant Island. Shackleton later died on South Georgia in 1922 and is buried in Grytviken.



<h2 class="wp-block-heading" id="h-pristine-nature-of-the-island">Pristine nature of the island</h2>



Today, South Georgia is a focus of conservation efforts. The eradication of invasive species, such as rats and reindeer, has been a significant success, allowing native wildlife to recover. 



Rats and mice were responsible for the decline of ground-nesting birds, including the South Georgia pipit, the island's only endemic bird. 



<a href="https://www.earth.com/news/reindeer-use-ultraviolet-vision-to-find-food-in-the-winter/" target="_blank" rel="noreferrer noopener">Reindeer</a>, which had been introduced for farming in the 19th century, caused extensive damage to the island’s vegetation, disrupting the habitat for native species.



South Georgia is uninhabited except for a small number of scientists and staff working at research stations and administrative facilities, emphasizing its role as a protected wilderness area and an essential site for understanding global environmental changes.



Its uninhabited status has helped preserve its pristine nature. Visitors to South Georgia must follow strict environmental guidelines to minimize human impact on this extraordinary island.



<h2 class="wp-block-heading" id="h-scientific-significance-of-remote-islands">Scientific significance of remote islands </h2>



Remote <a href="https://www.earth.com/news/plant-life-on-islands-loses-diversity-when-humans-arrive/" target="_blank" rel="noreferrer noopener">islands</a> are scientifically significant for several reasons. They often serve as unique ecosystems that can provide insights into evolutionary processes, biodiversity, and adaptation. 



Due to their isolation, species on remote islands may evolve differently from their mainland counterparts, resulting in the development of endemic species that exist nowhere else in the world. 



These islands also act as natural laboratories for studying the effects of climate change, human activity, and ecological interactions, as they are more vulnerable to disturbances. 



Moreover, remote islands can offer valuable information on the health of marine and terrestrial ecosystems, as their ecosystems are often less impacted by human-induced factors. This makes them ideal for studying natural processes in relatively undisturbed environments. 



The isolation of these islands can also help scientists study the patterns of species migration, colonization, and extinction.



Image Credit: ESA 



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South Georgia: One of the most remote islands in the world

Today's Image of the Day from NASA Earth Observatory features the Messak Settafet, a rocky plateau located in the central Sahara Desert. It is part of the greater Messak Plateau, which stretches between the Erg Uan Kasa and the Murzuq Sand Sea.&nbsp;



The plateau's surface is characterized by blackened sandstone, sculpted by thousands of years of wind erosion. This dark patina, often referred to as "desert varnish," adds to its distinctive appearance. The region is starkly beautiful but harsh, with extreme temperatures and minimal <a href="https://www.earth.com/news/even-desert-plants-are-not-immune-to-climate-stress/" target="_blank" rel="noreferrer noopener">vegetation</a>.



<h2 class="wp-block-heading" id="h-image-of-the-messak-settafet">Image of the Messak Settafet</h2>



“Towering over the desert in southwestern Libya, the Messak Settafet plateau resembles the wall of a giant fortress, with its dark, erosion-resistant sandstone separating the Ubari Sand Sea to the north and the Marzūq Sand Sea to the south,” noted NASA.



“The large outcrop of Cretaceous rock features a sharp escarpment on its north side. The cliff, some 300 meters (1,000 feet) high in places, is lined with a thin dark shadow.”&nbsp;



“Dark debris from rockfalls is visible to the north. Note that an optical illusion called relief inversion can make high-elevation areas appear low and vice versa when shadows appear on the northern side of a feature.”



<h2 class="wp-block-heading" id="h-archaeological-significance-of-the-plateau-nbsp">Archaeological significance of the plateau&nbsp;</h2>



Messak Settafet is often referred to as the "land of stone tools" because it is one of the world's largest sites for prehistoric tools.&nbsp;



The area is littered with countless <a href="https://search.app?link=https%3A%2F%2Fwww.earth.com%2Fnews%2Fstone-tool-discovery-challenges-entire-theory-of-human-evolution%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">stone tools</a> and artifacts dating back to various prehistoric periods, including the Acheulean and Neolithic. These tools offer insights into early human technology and adaptation to desert environments.



“Signs of ancient tool making cover much of the plateau’s surface,” said <a href="https://www.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA</a>. “According to one archaeological survey, people discarded so many stone tools and rock fragments on the plateau over hundreds of thousands of years that roughly 75 artifacts per square meter now carpet the surface.”&nbsp;



“That makes this one of the earliest known examples of hominins modifying an entire landscape, according to the University of Cambridge archaeologists who conducted the survey.”



“Other signs of ancient activity include the bright spots that dot the image. These areas were likely quarrying pits where people dug up rocks and crafted them into tools, the archaeologists reported.”&nbsp;



<h2 class="wp-block-heading" id="h-rock-art-on-the-plateau-nbsp">Rock art on the plateau&nbsp;</h2>



The plateau is home to numerous petroglyphs and <a href="https://www.earth.com/news/negev-petroglyphs-ancient-art-rock-carvings-face-erosion-fungi-lichens/" target="_blank" rel="noreferrer noopener">carvings</a>. These engravings depict animals, humans, and symbolic designs, providing valuable clues about the lives, beliefs, and environments of the region's ancient inhabitants.&nbsp;



“For instance, Wadi Mathendous, a prehistoric archaeological site located in the southern part of the plateau, contains engravings of rhinoceroses, crocodiles, hippopotamuses, fighting cats, giraffes, long-horned buffaloes, and elephants. The art is thought to be about 8,000 years old,” said NASA.



Some of the animals depicted, such as giraffes and elephants, indicate that the Sahara was once a <a href="https://search.app?link=https%3A%2F%2Fwww.earth.com%2Fnews%2Fa-lush-green-sahara-desert-helped-early-humans-migrate-out-of-africa%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">much wetter</a> and more hospitable environment.



<h2 class="wp-block-heading" id="h-cultural-significance-of-the-messak-settafet">Cultural significance of the Messak Settafet</h2>



Messak Settafet forms part of the Rock-Art Sites of Tadrart Acacus, a UNESCO World Heritage Site since 1985. This designation highlights the area's importance for understanding early human culture and environmental changes in the Sahara.



The plateau has been a critical area for studying the migration and adaptation of early humans. Its archaeological richness offers a glimpse into how humans thrived in this region during periods when the climate was wetter.



“Although the plateau now receives less than 0.4 inches of rain annually, clues in the landscape make clear it was once much wetter,” noted NASA.



“Deeply incised dried stream valleys, or wadis, crisscross the plateau, indicating significant past water flow. The small, bright features scattered across the plateau are sand and silt deposits left where water once pooled.”



The Messak Settafet, like many remote <a href="https://www.earth.com/news/sahara-desert-dust-storms-carry-harmful-bacteria-and-fungi-around-the-globe/" target="_blank" rel="noreferrer noopener">desert</a> regions, faces challenges such as erosion, vandalism of ancient rock art, and the potential impacts of development. 



Efforts to preserve its archaeological treasures are vital for protecting its cultural and scientific significance.



The image was captured November 17, 2024 by the Operational Land Imager-2 (OLI-2) on Landsat 9 on&nbsp;



Image Credit: NASA Earth Observatory



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Messak Settafet plateau in the Sahara Desert

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

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 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  

Geoffroy’s spider monkeys live high in the rainforest canopy, and are difficult to observe. Their shy behavior makes it challenging for scientists to track and protect them effectively. To address this, biologist Jenna Lawson implemented an innovative solution in 2021.



Lawson strategically placed 350 audio monitors across the Osa Peninsula in Costa Rica. 



The devices captured the sounds of the forest, allowing her to study the monkeys without disturbing them. This approach provided valuable insights into their movements and behavior.



<h2 class="wp-block-heading" id="h-new-era-of-conservation-technology">New era of conservation technology</h2>



The devices recorded forest sounds for a week, amassing vast data. By feeding this data into artificial intelligence (AI) systems trained to identify spider monkey calls, researchers gained insights that would otherwise take years to uncover.



This AI-driven initiative became one of the largest acoustic <a href="https://www.earth.com/news/deforestation-changes-social-behavior-in-monkeys/" target="_blank" rel="noreferrer noopener">wildlife studies</a> globally, and revealed troubling signs about the health of the habitats in which these animals live.



"They're the most sensitive of the primates that we have here," said Lawson. "The spider monkey would be the first animal to leave when there's signs of trouble. They would be the last animal to come back once forests are restored because they need mature, secondary and primary forest to be able to survive."



The monkeys avoid human-altered areas and rely on mature forests, making them sensitive indicators of environmental health.



The findings revealed that the monkeys avoid paved roads and plantations, which indicates that there are flaws in the government wildlife corridors which were designed to expand their range.



<h2 class="wp-block-heading" id="h-ai-monitoring-and-spider-monkey-conservation">AI monitoring and spider monkey conservation</h2>



Lawson’s work exemplifies how AI can support biodiversity efforts. Previous research has emphasized the potential of machine-learning techniques to manage vast datasets, which would enable faster, cheaper, and more precise ecological studies.



However, technical hurdles like humidity-damaged devices and accidental destruction by <a href="https://www.earth.com/news/fossils-reveal-the-lifestyle-of-an-extinct-caribbean-monkey/" target="_blank" rel="noreferrer noopener">animals</a> remain.



To tackle these challenges, Microsoft’s <a href="https://www.microsoft.com/en-us/research/group/ai-for-good-research-lab/" target="_blank" rel="noreferrer noopener">AI for Good Lab</a> introduced “Sparrow” - Solar-Powered Acoustic and Remote Recording Observation Watch. This energy-efficient device, designed to function autonomously for years, transmits data via low-Earth orbit satellites.



“Those remote places are also the most important places on the Earth from a biodiversity perspective,” said Juan Lavista Ferres, Microsoft’s chief data scientist.



Sparrow’s first test will monitor jaguars, birds, and spider monkeys along Colombia’s Magdalena River. 



By 2025, the project aims to deploy these devices on all continents and make the data accessible to researchers while protecting sensitive location information in order to avoid alerting potential poachers and animal traders.



“What we don’t want is these devices to ever be used for poachers to understand where the animals are,” Lavista Ferres said.



<h2 class="wp-block-heading" id="h-global-implications-for-conservation">Global implications for conservation</h2>



AI-powered acoustic monitoring has applications beyond studying rainforests. For instance, it could help sailors detect whale sounds in shipping lanes, thus reducing the risk of collisions.



This technology is transformative because it allows scientists to study wildlife without physically intruding on their habitats, which minimizes human influence on animal behavior. 



"We’re reducing our influence on their behavior. And also - they don’t want us here," Lawson explained.



However, challenges remain. Deploying such systems requires overcoming technical issues like equipment durability and environmental conditions. 



Equally important is collaboration with local communities. Lawson’s work around Costa Rica’s Corcovado National Park highlights this need. Landowner support was critical for placing audio monitors outside protected areas to enable a broader understanding of <a href="https://www.earth.com/news/marmosets-call-each-other-by-names-with-distinct-vocalizations/" target="_blank" rel="noreferrer noopener">animal</a> behavior.



<h2 class="wp-block-heading" id="h-future-conservation-efforts-for-spider-monkeys">Future conservation efforts for spider monkeys</h2>



Projects like Jenna Lawson’s and Microsoft’s Sparrow demonstrate how AI can revolutionize conservation efforts. 



These initiatives show that AI-powered tools can collect and analyze vast quantities of data, offering insights into animal <a href="https://www.earth.com/news/world-wildlife-conservation-day-2024-saving-species-from-extinction/" target="_blank" rel="noreferrer noopener">behavior</a> and habitat health that would be difficult to obtain otherwise.



However, realizing their full potential requires overcoming technical challenges, such as maintaining equipment in harsh environments, securing adequate funding, and addressing ethical concerns - including the safe and responsible use of collected data.



<h2 class="wp-block-heading" id="h-ai-assisted-wildlife-monitoring">AI-assisted wildlife monitoring</h2>



With 28% of plant and animal species currently at risk of extinction, AI-assisted wildlife monitoring offers a promising way to tackle biodiversity loss. 



By combining advanced technology with community-driven conservation efforts, scientists can gain a deeper understanding of ecosystems and implement effective protection strategies.



Endangered species like Geoffrey’s spider monkeys highlight the urgency of these efforts. Their unique role in the ecosystem and their vulnerability to habitat changes emphasize both the challenges of conservation and the hope that innovative solutions can bring. 



These remarkable creatures remind us of the biodiversity we stand to lose - and inspire action to preserve what can still be saved.



The study is published in the <a href="https://royalsocietypublishing.org/doi/full/10.1098/rspb.2022.2473">Proceedings of the Royal Society B</a>. 



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AI monitoring will help protect endangered spider monkeys

Geoffroy’s spider monkeys live high in the rainforest canopy, and...

When discussing solutions to climate change, most people think of renewable energy, electric vehicles, and nuclear energy. These technologies aim to reduce emissions and shift humanity toward a more sustainable future. 



However, one emerging technology, solar geoengineering, presents a compelling - if controversial - option for cooling the planet quickly.



While the idea of altering the atmosphere might sound like science fiction, its potential impact could be profound. 



According to a new study from the&nbsp;Georgia Tech School of Public Policy, solar geoengineering could save as many as&nbsp;400,000 lives annually&nbsp;by reducing temperature-related deaths caused by climate change. 



Published in the&nbsp;Proceedings of the National Academy of Sciences (PNAS), the study emphasizes that while the risks are real, the benefits might outweigh them significantly.



<h2 class="wp-block-heading" id="h-understanding-solar-geoengineering">Understanding solar geoengineering </h2>



Solar <a href="https://www.earth.com/news/should-we-risk-geoengineering-to-reverse-climate-change/" target="_blank" rel="noreferrer noopener">geoengineering</a> focuses on&nbsp;stratospheric aerosol injection (SAI), a process involving tiny reflective particles sprayed into the upper atmosphere. 



These particles bounce sunlight back into space, helping to cool the Earth. Researchers believe that by lowering global temperatures, SAI could provide humanity with a critical buffer while long-term solutions like emissions reduction and carbon removal are fully implemented.



"An important question is how the reduction in climate risks from solar geoengineering compares to the additional risks its use entails," noted study lead author Anthony Harding from the Georgia Tech <a href="https://spp.gatech.edu" target="_blank" rel="noreferrer noopener">School of Public Policy</a>.



The team, which included collaborators from <a href="https://www.princeton.edu" target="_blank" rel="noreferrer noopener">Princeton University</a> and the <a href="https://www.uchicago.edu/en" target="_blank" rel="noreferrer noopener">University of Chicago</a>, analyzed the potential life-saving impact of solar geoengineering. 



Using computer models and historical data on temperature-related death rates, they simulated a scenario where the global average temperature rises by 2.5°C from pre-industrial levels. 



The results showed that cooling the planet by just 1°C could prevent 400,000 deaths annually.



<h2 class="wp-block-heading" id="h-benefits-and-risks-of-solar-geoengineering">Benefits and risks of solar geoengineering</h2>



Despite its promise, solar geoengineering poses <a href="https://www.earth.com/news/survey-mother-nature-is-more-likely-to-solve-climate-change-than-geoengineering/" target="_blank" rel="noreferrer noopener">significant challenges</a>. Risks such as poorer air quality and ozone layer depletion could lead to serious health problems. 



However, the study found that the&nbsp;lives saved from cooling effects outnumber potential deaths caused by these risks by a factor of 13. Many of these lives would be saved in&nbsp;hotter, poorer regions, which are disproportionately affected by climate change.



On the other hand, the technology's potential is not universally positive. In cooler, wealthier regions, the decrease in global temperatures might lead to increased cold-related deaths.



The researchers emphasize that their findings represent an initial exploration of solar geoengineering’s effects and not a comprehensive evaluation of its global risks and benefits.



"This study offers a first step in quantifying the risks and benefits of solar geoengineering and shows that, for the risks we considered, the potential to save lives outweighs the direct risks,"&nbsp;Harding added.



<h2 class="wp-block-heading" id="h-broader-implications-and-ethical-concerns">Broader implications and ethical concerns</h2>



The study highlights the urgent need for more robust research into solar geoengineering. The&nbsp;<a href="https://www.nasonline.org" target="_blank" rel="noreferrer noopener">National Academies of Science</a>&nbsp;have recommended increased funding to evaluate the technology's safety and <a href="https://www.earth.com/news/geoengineering-can-we-dim-the-sun-to-avoid-climate-tipping-points/" target="_blank" rel="noreferrer noopener">effectiveness</a> further. 



However, critics, including the&nbsp;<a href="https://www.ucsusa.org" target="_blank" rel="noreferrer noopener">Union of Concerned Scientists</a>, warn that the environmental, ethical, and geopolitical risks are too significant to ignore. They argue that governments might use solar geoengineering as an excuse to delay difficult but necessary emissions cuts.



Solar geoengineering also raises concerns about unintended ecological consequences and potential conflicts over its deployment. For instance, countries might disagree on the ideal level of cooling or the acceptable risks, leading to geopolitical tensions.



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



The authors acknowledge that their research has some limitations. The study is based on idealized models and assumptions about aerosol distribution, population growth, and economic development.



These models cannot fully capture the complexities of real-world implementation. 



Additionally, the study does not explore solar geoengineering’s potential <a href="https://www.earth.com/news/can-geoengineering-save-the-doomsday-glacier/" target="_blank" rel="noreferrer noopener">impact on ecosystems</a>, politics, or the possibility of promoting complacency in reducing emissions.



<h2 class="wp-block-heading" id="h-solar-geoengineering-could-alleviate-suffering">Solar geoengineering could alleviate suffering </h2>



While solar geoengineering remains a controversial topic, its potential benefits make it a technology worth exploring further. For many regions, it could provide life-saving relief from climate-related heat.



"There's no perfect resolution to the climate crisis," said Harding. "Solar geoengineering entails risks, but it could also alleviate real suffering, so we need to better understand how the risks compare to the <a href="https://www.earth.com/news/we-are-changing-the-clouds-unintended-geoengineering-test-atlantic-warming/" target="_blank" rel="noreferrer noopener">benefits</a> to inform any potential future decisions around the technology."



As the global community searches for solutions to mitigate climate change, solar geoengineering could play a vital role. However, its adoption must come with a clear understanding of both its promises and its perils. 



Collaborative research and careful risk assessment will be crucial in determining whether this bold strategy becomes part of humanity’s fight against a warming planet.



The study is published in the journal <a href="https://www.pnas.org/doi/10.1073/pnas.2401801121" target="_blank" rel="noreferrer noopener">Proceedings of the National Academy of Sciences</a>.



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Solar geoengineering could save up to 400,000 lives each year

When discussing solutions to climate change, most people think of...

In an era teeming with spectacular inventions and discoveries, the possibilities for innovation in robotic technology seem endless. Among these breakthroughs, a team of scientists at the <a href="https://www.isct.ac.jp/en" target="_blank" rel="noreferrer noopener">Institute of Science, Tokyo</a>, has found a unique approach to robotic flight control that could reshape the industry.



Their method? Bio-inspired wind sensing using strain sensors on flexible wings. The research, led by Professor Hiroto Tanaka, demonstrates the potential of wing strain sensing to revolutionize flapping <a href="https://www.earth.com/news/engineers-create-perching-bird-like-robot/" target="_blank" rel="noreferrer noopener">aerial robots</a>.



Inspired by the natural strain receptors found in birds and insects, the researchers developed a method to detect wind direction with an impressive 99.5% accuracy using strain gauges and a convolutional neural network (CNN) model.



<h2 class="wp-block-heading" id="h-biological-inspiration-for-robotic-wings">Biological inspiration for robotic wings</h2>



Flying insects and birds possess mechanical receptors on their wings that collect strain sensory data, likely aiding their <a href="https://www.earth.com/video/exploring-the-incredible-flight-control-techniques-of-fruit-flies/" target="_blank" rel="noreferrer noopener">flight control</a>. 



These receptors enable them to detect changes in wind, body movement, and environmental conditions, allowing for responsive adjustments during flight. 



Researchers were inspired by these natural systems and sought to replicate their functionality in robotic wings.



"Small aerial robots cannot afford conventional flow-sensing apparatus due to severe limitations in weight and size. Hence, it would be beneficial if simple wing strain sensing could be utilized to directly recognize flow conditions without additional dedicated devices," explained Tanaka.



<h2 class="wp-block-heading" id="h-delicately-designed-wings-with-a-purpose">Delicately designed: Wings with a purpose</h2>



The team attached seven low-cost, widely available strain gauges to a flexible wing structure that mimics the wings of <a href="https://www.earth.com/news/hummingbirds-adjust-their-wings-to-fly-through-very-tiny-spaces/" target="_blank" rel="noreferrer noopener">hummingbirds</a>. 



These wings, composed of tapered shafts supporting wing film, were designed to closely resemble the structure of natural wings.



The wings were integrated into a flapping mechanism driven by a DC motor and Scotch yoke system, generating 12 flapping cycles per second. 



Exposing the setup to wind speeds of 0.8 m/s in a wind tunnel, the team measured wing strain under seven different wind directions (0°, 15°, 30°, 45°, 60°, 75°, and 90°), along with one no-wind condition.



The strain data was analyzed using a CNN model to classify the various wind conditions.



<h2 class="wp-block-heading" id="h-achieving-remarkable-results">Achieving remarkable results</h2>



The results were striking. The researchers achieved a 99.5% classification accuracy using the strain data from a complete <a href="https://www.earth.com/news/universal-equation-predicts-the-flapping-frequency-of-birds-insects-and-even-whales/" target="_blank" rel="noreferrer noopener">flapping</a> cycle.



Even with shorter data from just 0.2 flapping cycles, the accuracy remained high at 85.2%. Further analysis showed that even with data from a single strain gauge, classification accuracy ranged from 95.2% to 98.8% for one flapping cycle.



However, this dropped to 65.6% or lower when using the shorter 0.2-cycle data. 



Additionally, the removal of inner wing shafts led to reduced classification accuracy, highlighting the importance of biomimetic wing structures in enhancing wind-sensing capabilities.



<h2 class="wp-block-heading" id="h-a-vision-for-robotic-flight">A vision for robotic flight</h2>



"This study contributes to the growing understanding that hovering <a href="https://www.earth.com/news/bird-wings-inspire-improvements-in-airplane-safety/" target="_blank" rel="noreferrer noopener">birds</a> and insects may sensitively perceive wind through strain sensing of their flapping wings, which would be beneficial for responsive flight control," said Tanaka. 



"A similar system can be realized in biomimetic flapping-wing aerial robots using simple strain gauges."



The research showcases the immense potential of bio-inspired technology in advancing robotic flight. 



By learning from nature, these scientists have opened the door to smarter, more adaptable robots that can navigate complex environments with precision.



<h2 class="wp-block-heading" id="h-potential-applications-in-robotics-and-beyond">Potential applications in robotics and beyond</h2>



The implications of this research extend far beyond improving robotic flight. The use of strain sensors on flexible wings has the potential to revolutionize various industries.



For instance, these biomimetic systems could be integrated into small aerial robots designed for disaster response, where precise flight control is crucial in navigating challenging environments. 



Drones equipped with this technology could also excel in tasks such as environmental monitoring, search and rescue operations, and agricultural applications.



Additionally, the lightweight and cost-effective nature of strain gauges makes them an attractive option for scaling up these systems in both commercial and military contexts. 



For example, delivery drones operating in urban areas could benefit from the enhanced wind-sensing capabilities, ensuring smoother flights in unpredictable weather.



This study also opens avenues for further research in biomimicry. It could potentially inspire developments in other areas, such as underwater robotics or even space exploration, where adaptive movement in fluid-like environments is essential.



The full study was published in the journal <a href="https://onlinelibrary.wiley.com/doi/10.1002/aisy.202400473" target="_blank" rel="noreferrer noopener">Advanced Intelligent Systems</a>.



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Hummingbird wings: The future of robotic flight

In an era teeming with spectacular inventions and discoveries, the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Santiago, the capital city of Chile. The city is located in the center of the Santiago Metropolitan Region, which has a population of about eight million people.&nbsp;



&#8216;The weather of Santiago resembles the Mediterranean climate with dry and warm summers with temperatures reaching up to 35°C (from October to March) and cool and humid winters that can drop to 0°C (from April to September).&#8221;



&#8220;The city lies in the centre of the country’s central valley around 80 km from the Pacific Ocean to the west and borders Argentina to the east. A tiny part of Argentina is visible in the top-right corner of the image where the mountain crest of the Andes Mountains acts as a divider between the two countries,&#8221; says ESA.



Video/ Image Credit: ESA



&#8211;&#8212;



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



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Santiago, Chile in South America