<p>Today's Image of the Day from NASA Earth Observatory features a satellite view of retreating glaciers in Alaska, where meltwater is rapidly expanding glacial lakes. </p>



<p>“In parts of Alaska, water is replacing ice. As glaciers thin and <a href="https://www.earth.com/news/satellite-images-reveal-hidden-retreat-of-arctic-glaciers/" target="_blank" rel="noreferrer noopener">retreat</a>, meltwater collects at their fronts, forming proglacial lakes. According to an analysis by Mauri Pelto, a glaciologist at Nichols College, three such lakes in the southeastern part of the state have grown rapidly in recent decades,” said <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA</a>.</p>



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



<p>“A trio of glaciers - Yakutat, Alsek, and Grand Plateau - descend from inland mountains and flow onto the coastal plain southeast of Yakutat borough, ending at Harlequin Lake, Alsek Lake, and Grand Plateau Lake,” noted NASA.&nbsp;</p>



<p>The retreat of the glaciers, as well as the growth of the lakes, are visible in the image. When compared to an <a href="https://eoimages.gsfc.nasa.gov/images/imagerecords/153000/153638/fastestlake_tm5_19840705_lrg.jpg" target="_blank" rel="noreferrer noopener">image</a> captured by Landsat 5 in the summer of 1984, the changes are even more evident.</p>



<p>NASA elaborated on the extent of the glacier retreat from 1984 to 2024. “During this period, Yakutat Glacier’s main arm retreated 4.3 miles, while Alsek Glacier’s northern and southern arms retreated 3.3 miles and 3.4 miles, respectively. Grand Plateau Glacier’s northern arm lost the most, retreating 4.8 miles.”</p>



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



<p>“Collectively, the three lakes more than doubled in size over 40 years. In 1984, they covered about 50 square miles. By 2024, they spanned 90 square miles. That’s an area larger than Seneca Lake (67 square miles) - one of the Finger Lakes in New York, which also have a glacial origin,” said NASA.</p>



<p>Pelto noted that the lakes forming in this region are immense - starting at the mountains and spreading toward the coast - making this a new lake district that is unique in our nation.</p>



<p>“Millions of other lakes, named and unnamed, dot the state. But this system has grown fast, so much so that Pelto thinks it might represent the fastest lake growth in the United States this century,” said NASA.</p>



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



<p>Glacier retreat is a significant phenomenon driven primarily by global warming the results from rising greenhouse gas <a href="https://www.earth.com/news/global-carbon-dioxide-emissions-hit-a-record-high-in-2023/" target="_blank" rel="noreferrer noopener">emissions</a>.&nbsp;</p>



<p>As temperatures rise, glaciers lose more ice during the summer melt than they can regain in winter snowfall, causing them to shrink over time. This process has profound implications for ecosystems, water resources, and global sea levels.</p>



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



<p>When glaciers retreat, they often leave behind depressions in the landscape that can fill with meltwater, forming glacial lakes. These lakes are typically bounded by natural dams made of rock, ice, or moraine - accumulations of debris left behind by the glacier's movement.&nbsp;</p>



<p>Over the past century, the number and size of glacial lakes worldwide have increased significantly due to the accelerating pace of <a href="https://www.earth.com/news/tropical-glaciers-offer-a-glimpse-of-our-harsh-climate-reality/" target="_blank" rel="noreferrer noopener">glacier</a> retreat. This trend is especially evident in high-altitude regions like the Himalayas, the Andes, and the Alps, as well as in polar areas such as Alaska and Greenland.</p>



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



<p>Glacial lakes can have both positive and negative impacts. They provide critical water sources for downstream communities, support biodiversity, and sometimes offer opportunities for hydropower development or tourism.&nbsp;</p>



<p>However, they also pose serious risks. The dams holding back these lakes can fail suddenly, causing glacial lake outburst floods (GLOFs). These catastrophic events can devastate downstream areas, destroying infrastructure, agricultural lands, and habitats while endangering human lives.</p>



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



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



<p>Monitoring these changes is essential to mitigate associated risks and adapt to the evolving landscape shaped by a <a href="https://search.app?link=https%3A%2F%2Fwww.earth.com%2Fnews%2Fperu-has-lost-over-half-of-its-glaciers-in-six-decades%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">warming planet</a>.</p>



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



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



<p>Melting glaciers contribute significantly to global <a href="https://www.earth.com/news/emergency-meeting-reveals-the-alarming-extent-of-antarcticas-ice-loss/" target="_blank" rel="noreferrer noopener">sea level rise</a>, which threatens coastal communities and ecosystems.</p>



<p>The retreat of glaciers is considered one of the clearest indicators of climate change.&nbsp;Some glaciers are retreating at unprecedented rates, indicating accelerating climate impacts.</p>



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



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



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Retreating glaciers and expanding meltwater lakes in Alaska

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

<p>Today's <strong>Image of the Day</strong> from the European Space Agency features NGC 1333, a reflection nebula located in the Perseus molecular cloud about 960 light-years away from Earth. The photo is a mosaic of images captured by the James Webb Space Telescope.</p>



<p>“Webb’s superb sensitivity allows astronomers to investigate young objects with extremely low masses. Some of the faintest ‘stars’ in the picture are in fact newly born free-floating brown dwarfs with masses comparable to those of giant planets,” noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.</p>



<p>The same cluster was featured in the 33rd anniversary image of the Hubble Space Telescope in April 2023.&nbsp;</p>



<p>According to ESA, Hubble’s image just scratched the surface of this region, because clouds of dust obscure much of the star formation process. </p>



<p>"Observing with larger aperture and in the infrared part of the spectrum, Webb is capable of peering through the dusty veil to reveal newborn stars, brown dwarfs and planetary mass objects."</p>



<h2 class="wp-block-heading" id="h-webb-s-view-of-ngc-1333">Webb’s view of NGC 1333</h2>



<p>ESA noted that the center of the image presents a deep peek into the heart of the NGC 1333 cloud.&nbsp;</p>



<p>“Across the image we see large patches of orange, which represent gas glowing in the infrared. These so-called Herbig-Haro objects form when ionized material ejected from young stars collides with the surrounding cloud. They are hallmarks of a very active site of star formation."</p>



<p>The disks of gas and dust that surround the <a href="https://www.earth.com/news/newly-discovered-stars-milky-way-are-old-as-universe/" target="_blank" rel="noreferrer noopener">stars</a> in this image may eventually produce planetary systems.&nbsp;</p>



<h2 class="wp-block-heading" id="h-stars-in-the-sun-s-birth-cluster">Stars in the Sun's birth cluster</h2>



<p>“Similar to the young stars in this mosaic, our own Sun and planets formed inside a dusty molecular cloud, 4.6 billion years ago. Our Sun did not form in isolation but as part of a cluster, which was perhaps even more massive than NGC 1333,” explained ESA.</p>



<p>Over time, the stars in the Sun's birth cluster would have drifted apart due to gravitational interactions and the dispersion of gas in the region.</p>



<p>Astronomers have been studying certain clues, such as isotopic signatures in meteorites, that hint the Sun may have formed near massive stars. These stars likely produced supernovae, which could have influenced the early <a href="https://www.earth.com/news/mysterious-objects-spotted-in-the-outer-solar-system-beyond-pluto/" target="_blank" rel="noreferrer noopener">solar system</a> by injecting heavy elements like iron-60.</p>



<h2 class="wp-block-heading" id="h-star-formation-in-ngc-1333">Star formation in NGC 1333</h2>



<p>NGC 1333 is a vibrant example of a stellar nursery, where active <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 ongoing. It is known for its chaotic appearance, shaped by the interactions between newborn stars and the surrounding material.</p>



<p>Within NGC 1333, astronomers have observed a high level of turbulence, which makes the region dynamic and complex. </p>



<p>The disturbances are caused by the outflows of young stars as they eject material into their surroundings, creating shock waves and influencing further star formation. </p>



<p>These outflows are often seen as jets, which are visible in multiple wavelengths of light, especially infrared, as the surrounding dust absorbs visible light.</p>



<h2 class="wp-block-heading" id="h-early-stages-of-planet-formation">Early stages of planet formation </h2>



<p>NGC 1333 is also an area of interest for studying the early stages of star and <a href="https://www.earth.com/news/planet-formation-new-insights-mechanics-physics/" target="_blank" rel="noreferrer noopener">planet formation</a>, as many of the stars within the cluster are in their infancy.</p>



<p>These stars are still in the process of gathering material and developing protoplanetary disks.&nbsp;</p>



<p>In images, NGC 1333 is marked by bright patches of blue and red, representing reflection <a href="https://www.earth.com/news/six-rogue-worlds-discovered-inside-a-young-star-forming-nebula/" target="_blank" rel="noreferrer noopener">nebulae</a> and the ionized gas created by energetic young stars.&nbsp;</p>



<h2 class="wp-block-heading" id="h-the-perseus-molecular-cloud-nbsp">The Perseus molecular cloud&nbsp;</h2>



<p>The Perseus molecular cloud is a vast region of cold gas and dust located about 600 light-years away from Earth in the constellation <a href="https://www.earth.com/news/1500-billion-orphan-stars-discovered-in-the-perseus-galaxy-cluster/" target="_blank" rel="noreferrer noopener">Perseus</a>.&nbsp;</p>



<p>It is one of the most studied star-forming regions in our galaxy due to its relative proximity and the diversity of its young stellar objects. This cloud spans several hundred light-years and contains dense pockets of gas where new stars are actively forming.&nbsp;</p>



<p>These areas are often enshrouded in thick dust, which obscures them in visible light but allows astronomers to study them using infrared and radio wavelengths.</p>



<p>The Perseus molecular cloud is particularly interesting because of the chemistry taking place within it, including the formation of complex organic molecules that could be precursors to life.&nbsp;</p>



<p>Image Credit<strong>: </strong>ESA/Webb, NASA &amp; CSA</p>



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Stellar nursery shines in the Perseus cloud

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

<p>Today's Image of the Day from the European Space Agency features Messier 78 (M78), a reflection nebula located in the constellation Orion about 1,350 light-years away from Earth.&nbsp;</p>



<p>This image was released as part of the initial series of observations from ESA's <a href="https://www.esa.int/Science_Exploration/Space_Science/Euclid" target="_blank" rel="noreferrer noopener">Euclid space mission</a>.&nbsp;</p>



<p>All data collected during these early observations, including a series of incredible <a href="https://www.esa.int/Science_Exploration/Space_Science/Euclid/Euclid_s_first_images_the_dazzling_edge_of_darkness" target="_blank" rel="noreferrer noopener">new views</a> of the nearby universe, is available to the public.&nbsp;</p>



<h2 class="wp-block-heading" id="h-image-of-messier-78">Image of Messier 78</h2>



<p>Messier 78 is a dynamic region of star formation that is obscured by cosmic dust in this high-resolution image captured by the Euclid space telescope.</p>



<p>This specific view highlights how young stars generate winds of charged particles, carving out “cavities” in the molecular clouds around them.&nbsp;</p>



<p>The blue hues in the image represent ionized atomic hydrogen, which is a primary component of the cloud, while the red indicates the absorption and scattering of light by dust particles.</p>



<p>The image captures hundreds of stars varying in brightness, illuminating their nebulous, purple surroundings. A dark, arch-like structure stretches from the upper left to the bottom right of the frame, merging into the densest, darkest clouds at the image’s base.</p>



<h2 class="wp-block-heading" id="h-active-site-of-star-formation-nbsp">Active site of star formation&nbsp;</h2>



<p>Messier 78 is not just a single nebula but part of a larger complex of stars and nebulous regions in <a href="https://www.earth.com/news/orion-nebula-destroys-an-oceans-worth-of-water-every-month/" target="_blank" rel="noreferrer noopener">Orion</a>, which includes various other objects like dark nebulae that are visible as patches blocking light from behind.</p>



<p>This region is an active site of star formation, featuring many young stars and protostars, which are stars in the early stages of formation.&nbsp;</p>



<h2 class="wp-block-heading" id="h-viewing-messier-78">Viewing Messier 78</h2>



<p>M78 is easily observable with small telescopes, and it appears as a hazy patch of light with two prominent stars near its center, which illuminate the surrounding dust.&nbsp;</p>



<p>The nebula is also a favorite among amateur astronomers for its beauty and relatively bright appearance.</p>



<h2 class="wp-block-heading" id="h-subject-of-scientific-interest-nbsp">Subject of scientific interest&nbsp;</h2>



<p>Messier 78 is fascinating not only for its visual beauty but also for its scientific interest, particularly in the study of <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> and interstellar matter.&nbsp;</p>



<p>The nebula consists of dense, cold gas and dust, which are essential ingredients for the birth of new stars.&nbsp;</p>



<p>The intense blue light that characterizes M78 is due to the reflection of starlight off these dust particles - a process known as scattering.</p>



<h2 class="wp-block-heading" id="h-region-surrounding-messier-78-nbsp">Region surrounding Messier 78&nbsp;</h2>



<p>The region surrounding M78 includes several other interesting features. For instance, there are Herbig-Haro objects within it, which are small patches of nebulosity associated with <a href="https://www.earth.com/news/new-molecule-detected-in-space-where-stars-are-born/" target="_blank" rel="noreferrer noopener">newly born stars</a>.&nbsp;</p>



<p>These objects are formed when gas ejected by young stars collides with clouds of gas and dust at high speeds, creating shock waves that glow brightly.</p>



<h2 class="wp-block-heading" id="h-earliest-stages-of-star-development-nbsp">Earliest stages of star development&nbsp;</h2>



<p>Additionally, infrared observations of M78 have revealed much about the dust and colder objects in the area, which are not visible in optical light.&nbsp;</p>



<p>The observations have helped astronomers identify numerous young stars and brown dwarfs (objects that are too large to be planets and too small to be stars) within the nebula.&nbsp;</p>



<p>This makes M78 a critical area for studying the earliest stages of star development and the properties of the interstellar medium.</p>



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



<p>The <a href="https://www.earth.com/news/new-batch-of-brilliant-images-from-the-euclid-mission-live-up-to-the-hype/" target="_blank" rel="noreferrer noopener">Euclid space mission</a> is designed to study the dark universe, particularly focusing on dark energy and dark matter. These components are believed to drive the accelerating expansion of the universe and shape its large-scale structure. </p>



<p>The mission aims to map the geometry of the dark universe and better understand the physics of the cosmos.</p>



<h3 class="wp-block-heading" id="h-observing-billions-of-galaxies-nbsp">Observing billions of galaxies&nbsp;</h3>



<p>Euclid uses two primary scientific instruments: a visible light camera (VIS) and a near-infrared spectrometer and photometer (NISP).&nbsp;</p>



<p>These instruments will allow Euclid to measure the shapes and redshifts of galaxies at distances of up to 10 billion light-years. By surveying more than a third of the sky, the mission is expected to observe several billion galaxies.</p>



<h3 class="wp-block-heading" id="h-studying-the-dark-universe-nbsp">Studying the dark universe&nbsp;</h3>



<p>The data collected will help astronomers in studying the effects of dark matter and dark energy in depth, testing cosmological models, and exploring new theories about the nature of the universe.&nbsp;</p>



<p>The mission, named after the ancient Greek mathematician Euclid, seeks to address key questions related to the structure of the universe and the fundamental laws of physics governing its evolution and expansion.</p>



<p>Image Credit: European Space Agency&nbsp;</p>



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Messier 78: Young stars shine through dense dust

<p>Today's <strong>Image of the Day</strong> from the European Space Agency showcases the striking beauty of the planetary nebula NGC 2899, which resembles a moth in flight. The photo was captured by the Hubble Space Telescope.</p>



<p>“The planetary nebula NGC 2899 is shaped like a single macaroni noodle, with its edges pointed up, but its edge-on central torus is semi-transparent in the middle,” noted <a href="https://www.esa.int/ESA_Multimedia/Images" target="_blank" rel="noreferrer noopener">ESA</a>.</p>



<p>“The top and bottom edges are thick and orange. The center is semi-transparent blue and green. The wider central region looks roughly like a moth, also filled with semi-transparent blue and green.”</p>



<h2 class="wp-block-heading" id="h-defining-features-of-the-planetary-nebula">Defining features of the planetary nebula</h2>



<p>The nebula features a bipolar, cylindrical outflow of gas extending diagonally, driven by intense radiation and stellar winds from a central <a href="https://www.earth.com/news/white-dwarf-planets-are-more-habitable-than-we-thought/" target="_blank" rel="noreferrer noopener">white dwarf</a> with a scorching temperature of nearly 22,000 degrees Celsius.&nbsp;</p>



<p>“In fact, there may be two companion stars that are interacting and sculpting the nebula, which is pinched in the middle by a fragmented ring or torus - looking like a half-eaten donut,” said ESA.</p>



<p>Streams of gaseous “pillars” extend outward, all pointing back toward the central source of energy. The vibrant colors in the image come from glowing hydrogen and oxygen gases.&nbsp;</p>



<h2 class="wp-block-heading" id="h-discovery-and-significance-of-ngc-2899">Discovery and significance of NGC 2899</h2>



<p>NGC 2899 was discovered by British astronomer John Herschel on March 2, 1835, during his survey of the southern skies from the Cape of Good Hope in South Africa. Herschel cataloged many deep-sky objects in the southern hemisphere, contributing significantly to the New General Catalogue (NGC) compiled later by John Louis Emil Dreyer.</p>



<p>NGC 2899 is located approximately 4,500 light-years from Earth in the southern constellation Vela, which is part of the larger Vela-Puppis-Carina region of the Milky Way known for its rich <a href="https://www.earth.com/news/fluffy-molecular-clouds-may-change-our-understanding-of-star-formation/" target="_blank" rel="noreferrer noopener">star-forming activity</a> and remnants of past stellar explosions.&nbsp;</p>



<p>Vela, whose name means "sails" in Latin, represents the sails of the ancient Greek mythological ship Argo Navis. This region of the sky is particularly abundant in nebulae, star clusters, and other deep-sky objects, making it a focal point for astronomical observations.&nbsp;</p>



<p>The nebula’s distance places it well within our galaxy, offering astronomers a valuable glimpse into the later stages of stellar evolution and the processes that sculpt and illuminate planetary nebulae.</p>



<h2 class="wp-block-heading" id="h-what-is-a-planetary-nebula">What is a planetary nebula?</h2>



<p>Nebulae are vast clouds of gas and dust in space, often serving as the birthplaces or remnants of stars.&nbsp;</p>



<p>They come in various types, including emission nebulae that glow due to ionized gases energized by nearby stars, reflection nebulae that shine by scattering starlight, and dark nebulae that obscure light from background <a href="https://www.earth.com/news/runaway-star-may-be-dragging-a-planet-along-with-it/" target="_blank" rel="noreferrer noopener">stars</a>.&nbsp;</p>



<p>Planetary nebulae form when dying stars shed their outer layers, creating colorful, often symmetrical shapes. Nebulae can span light-years across and are key to understanding the life cycles of stars and the structure of galaxies.</p>



<h2 class="wp-block-heading" id="h-the-fate-of-dying-stars">The fate of dying stars</h2>



<p>Not all dying stars become planetary nebulae. In fact, stars much more massive than the Sun follow a very different and far more violent path.&nbsp;</p>



<p>These massive stars end their lives in dramatic supernova explosions, releasing tremendous energy and scattering heavy elements into space, which enriches the interstellar medium.&nbsp;</p>



<p>What remains after the explosion depends on the star’s mass. The collapsed core can form a neutron star - an incredibly dense object composed mostly of neutrons. Or, if the star was even more massive, it may create a <a href="https://www.earth.com/news/astronomers-confirm-lone-black-hole-wandering-through-our-galaxy/" target="_blank" rel="noreferrer noopener">black hole</a>, where gravity is so intense that not even light can escape.</p>



<h2 class="wp-block-heading" id="h-examples-of-winged-nebulae-nbsp">Examples of “winged” nebulae&nbsp;</h2>



<p>Several well-known nebulae are noted for their "winged" or symmetrical, wing-like appearances, often earning them evocative nicknames.&nbsp;</p>



<p>One of the most famous is the Butterfly Nebula, located in the constellation Scorpius. This planetary <a href="https://www.earth.com/news/dragons-egg-nebula-is-a-truly-stunning-sight-to-behold/" target="_blank" rel="noreferrer noopener">nebula</a> displays two expansive lobes that resemble butterfly wings, shaped by fast stellar winds from a dying star.</p>



<p>The Omega Nebula (also known as the Swan Nebula) in the constellation Sagittarius is a bright star-forming region that has been said to resemble a swan in flight. It has broad, glowing "wings" formed by clouds of ionized hydrogen gas. </p>



<p>Similarly, the Eagle Nebula has an overall shape reminiscent of a bird with outstretched wings, which inspired its name. It is located in the constellation Serpens and home to the iconic "Pillars of Creation."</p>



<p>Image Credit: ESA</p>



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Planetary nebula with ethereal wings captured by Hubble

<p>Today's <strong>Image of the Day</strong> from the European Space Agency features the vibrant colors of the Mawrth Vallis region of Mars. The image reveals a landscape abundant in iron, magnesium, and aluminum.&nbsp;</p>



<p>Mawrth Vallis lies just south of the dichotomy boundary, a ridge marking the divide between Mars' southern highlands and northern lowlands. Layered, clay-rich deposits found in this valley indicate prolonged interactions with water. </p>



<p>Mawrth Vallis is considered a prime candidate for studying past habitability and the potential for preserved biosignatures. The region continues to captivate scientists due to its geological complexity and history of <a href="https://www.earth.com/news/mars-has-a-water-reservoir-two-miles-deep-enough-to-fill-earths-red-sea/" target="_blank" rel="noreferrer noopener">liquid water</a> flow. </p>



<h2 class="wp-block-heading" id="h-the-colors-of-mars">The colors of Mars</h2>



<p><a href="https://www.earth.com/news/air-samples-from-mars-could-reveal-fascinating-secrets/" target="_blank" rel="noreferrer noopener">Mars</a> gets its distinctive red color from iron oxides, or rust, on its surface. The Martian soil and dust are rich in iron minerals, which oxidize when exposed to the small amounts of oxygen present in the Martian atmosphere.&nbsp;</p>



<p>This oxidation process gives the planet its reddish hue, similar to how iron objects on Earth develop rust. </p>



<p>The scattering of sunlight by these iron oxide particles further enhances the reddish appearance when viewed from a distance. However, the human eye can only perceive a fraction of Mars' <a href="https://www.earth.com/news/mars-captured-in-true-color-like-youve-never-seen-the-red-planet-before/" target="_blank" rel="noreferrer noopener">true color</a> palette.&nbsp;</p>



<h2 class="wp-block-heading" id="h-striking-colors-revealed">Striking colors revealed</h2>



<p>The European Colour and Stereo Surface Imaging System (CaSSIS) aboard the ExoMars Trace Gas Orbiter (TGO) offers a more detailed view, showcasing a striking diversity of colors.&nbsp;</p>



<p>This CaSSIS <a href="https://www.esa.int/ESA_Multimedia/Images/2024/06/Metallic_Mars_landscape" target="_blank" rel="noreferrer noopener">image</a> reveals yellow layers rich in iron and magnesium clays, overlain by white and blue layers abundant in aluminum.&nbsp;</p>



<p>The area is draped by a dark, heavily eroded layer, illustrating a vibrant, metallic landscape formed around 3.6 billion years ago.</p>



<h2 class="wp-block-heading" id="h-upcoming-rosalind-franklin-mission">Upcoming Rosalind Franklin mission</h2>



<p>The Rosalind Franklin mission is a joint mission by the European Space Agency (ESA) and Roscosmos aimed at exploring the surface of Mars to search for signs of past or present life. </p>



<p>The mission is named after Rosalind Franklin, the pioneering British scientist whose work was crucial in the discovery of DNA's structure.</p>



<p>The rover is designed to drill up to two meters below the Martian surface, where it is believed any signs of life may be better preserved, away from the harsh surface radiation. </p>



<p>The Rosalind Franklin rover was originally scheduled to launch in 2020, but technical delays and the COVID-19 pandemic pushed the launch window to 2028. </p>



<p>Once on Mars, the rover will collaborate with other missions like NASA's Perseverance and Curiosity rovers to advance our understanding of the Red Planet's habitability and history.</p>



<h2 class="wp-block-heading" id="h-studying-mars-ancient-past">Studying Mars’ ancient past</h2>



<p>While Rosalind Franklin prepares for its mission, the TGO remains in orbit, conducting crucial research to unravel Mars' ancient past and assess its potential <a href="https://www.earth.com/news/secrets-of-mars-seismic-discoveries-and-the-quest-for-past-life/" target="_blank" rel="noreferrer noopener">habitability</a>.&nbsp;</p>



<p>Since beginning its full science mission in 2018, TGO has not only captured stunning images but also provided a comprehensive inventory of Mars' atmospheric gases and mapped water-rich locations on the planet's surface.</p>



<p>For six years, CaSSIS has delivered breathtaking views of Mars in vivid color, documenting features ranging from volcanic landscapes to active dust devils and immense sand dunes.&nbsp;</p>



<p>Understanding Mars' water history and its implications for past <a href="https://www.earth.com/news/mars-is-letting-out-mysterious-methane-burps-but-why/" target="_blank" rel="noreferrer noopener">life</a> remains a core focus of ESA’s ExoMars missions.</p>



<h2 class="wp-block-heading" id="h-metals-on-mars">Metals on Mars</h2>



<p>Mars is rich in various metals that contribute to its geological and mineralogical diversity. </p>



<p>While iron is the most prominent, magnesium is also abundant. It is often found in the form of clays, contributing to the planet's diverse mineral composition. </p>



<p>Aluminum is another significant metal present on Mars, commonly found in layered deposits and sediments. </p>



<h2 class="wp-block-heading" id="h-major-changes-over-time">Major changes over time</h2>



<p>The metals are not evenly distributed but are found in various concentrations across the Martian surface. </p>



<p>For instance, regions like Mawrth Vallis exhibit a complex layering of different metal-rich minerals, including iron and magnesium-rich clays overlain by aluminium-rich layers.&nbsp;</p>



<p>This diversity indicates a rich geological history involving water activity, volcanic processes, and sedimentary deposition.</p>



<p>The presence of these metals suggests that Mars has undergone significant chemical and physical processes over billions of years, shaping its current landscape.&nbsp;</p>



<p>Understanding the distribution and composition of metals on Mars helps scientists piece together the planet's history and assess its past potential for habitability.</p>



<p>Image Credit: ESA/TGO/CaSSIS</p>



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Metallic Mars: The diverse colors of the Red Planet

<p>Sharks have glided through oceans for more than 450 million years, relying on skeletons made not of bone but of stiff, mineralised cartilage.</p>



<p>Their vertebral columns act like coiled springs, storing and releasing energy with every tail beat, even as the <a href="https://www.earth.com/news/offshore-wind-farms-threaten-electric-sensitive-sharks/" target="_blank" rel="noreferrer noopener">fish</a> reach speeds of twenty miles per hour or vault clear of the water in spinning leaps.</p>



<p>Scientists have long known that this mechanical efficiency stems from a cleverly reinforced spine, yet only now are researchers imaging those reinforcements at the nanoscale.</p>



<h2 class="wp-block-heading" id="h-mapping-cartilage-in-3d">Mapping cartilage in 3D</h2>



<p>A team from <a href="https://www.fau.edu/" target="_blank" rel="noreferrer noopener">Florida Atlantic University</a> (FAU), the <a href="https://www.desy.de/index_eng.html" target="_blank" rel="noreferrer noopener">German Electron Synchrotron</a> (DESY), and <a href="https://www.fisheries.noaa.gov/" target="_blank" rel="noreferrer noopener">NOAA Fisheries</a> used synchrotron X-ray nanotomography to map the internal architecture of blacktip shark vertebrae in three dimensions.</p>



<p>They paired scans with mechanical tests, squeezing tiny segments while tracking how they bent and cracked. The images revealed two layers inside the mineralized cartilage: a hard outer shell (corpus calcareum) and a softer inner core (intermediale).</p>



<p>Both zones are packed with <a href="https://www.earth.com/news/organic-molecules-collagen-discovered-in-66-million-year-old-dinosaur-bones/" target="_blank" rel="noreferrer noopener">collagen</a> fibers infused with bioapatite, the same calcium-phosphate mineral that stiffens human bone. Yet their arrangements differ.</p>



<p>Porous plates of mineralized tissue are supported by thick struts, allowing the shark skeleton to resist forces from many directions. This is essential for an animal that swims continuously and bends its body thousands of times each hour.</p>



<p>At even higher magnification, the scientists saw needles of bioapatite aligned with the collagen strands. They also discovered helically wound fiber layers that resemble plywood on a microscopic scale. </p>



<p>Under load, those helices hinder cracks from running unchecked, distributing stress through a web of stiff mineral and stretchy protein.</p>



<h2 class="wp-block-heading" id="h-nature-s-recipe-for-resilience">Nature’s recipe for resilience</h2>



<p>Study senior author Vivian Merk is an assistant professor of chemistry, ocean and mechanical engineering, and biomedical engineering at FAU.</p>



<p>“Nature builds remarkably strong materials by combining minerals with biological polymers, such as collagen - a process known as biomineralization," said Merk. "This strategy allows creatures like shrimp, crustaceans, and even humans to develop tough, resilient <a href="https://www.earth.com/news/dead-coral-skeletons-prevent-reefs-from-recovering/" target="_blank" rel="noreferrer noopener">skeletons</a>.”</p>



<p>“Sharks are a striking example. Their mineral-reinforced spines work like springs, flexing and storing energy as they swim. By learning how they build such tough yet adaptable skeletons, we hope to inspire the design of next-generation materials.”</p>



<p>Under compression, vertebrae yielded slightly on the first cycle and cracked only after a second round of stress. Even then, the fracture plane remained confined to one mineral layer, evidence that the helices and porous scaffolds localize damage rather than letting it propagate.</p>



<p>“After hundreds of millions of years of evolution, we can now finally see how shark cartilage works at the nanoscale - and learn from them,” said co-author Marianne Porter, an associate professor of biological sciences at FAU.</p>



<p>“We’re discovering how tiny mineral structures and collagen fibers come together to create a material that’s both strong and flexible, perfectly adapted for a shark’s powerful swimming. These insights could help us design better materials by following nature’s blueprint.”</p>



<h2 class="wp-block-heading" id="h-shark-skeletons-inspire-design">Shark skeletons inspire design</h2>



<p>Blacktip sharks roam warm coastal waters worldwide. Their quick turns and aerial spins place punishing loads on the spine, making them ideal models for impact-resistant design. </p>



<p>The layered “sharkitecture” identified in the study could guide the development of everything from lighter body armor to longer-lasting joint implants.</p>



<p>“This research highlights the power of interdisciplinary collaboration,” said Stella Batalama, dean of FAU’s College of Engineering and Computer Science. “By bringing together engineers, biologists, and materials scientists, we’ve uncovered how nature builds strong yet flexible materials.”</p>



<p>“The layered, fiber-reinforced structure of shark cartilage offers a compelling model for high-performance, resilient design, which holds promise for developing advanced materials from medical implants to impact-resistant gear.”</p>



<h2 class="wp-block-heading" id="h-cartilage-wins-in-evolution">Cartilage wins in evolution</h2>



<p>Unlike bony fish, sharks never switch to a calcium-phosphate skeleton during development. Their cartilaginous framework, reinforced by bioapatite only at strategic sites, saves weight without sacrificing stiffness.</p>



<p>The new nanoscale images suggest evolution achieved that balance through multiscale ordering. Collagen fibrils form bundles, which twist into helices. These helices embed in mineral plates, which then stack into porous columns that combine load-bearing strength with flexibility.</p>



<p>Because collagen and bioapatite are common to many vertebrates, the principles observed in sharks could be translated to human health.</p>



<p>Engineers might mimic the helical layering to make fracture-resistant composites, or apply the plate-and-strut motif to maximize strength while retaining lightness in aerospace parts.</p>



<p>Surgeons could one day use customized implants modeled on shark cartilage to promote bone integration and reduce fatigue failure.</p>



<h2 class="wp-block-heading" id="h-shark-tech-from-the-deep">Shark tech from the deep</h2>



<p>The study adds to a growing inventory of marine organisms whose microstructures inspire technology, from manta-ray-inspired filters to cephalopod-inspired <a href="https://www.earth.com/news/how-squid-power-their-amazing-camouflage-abilities/" target="_blank" rel="noreferrer noopener">camouflage</a>. Shark spines now join that list, revealing how evolution transforms humble ingredients - protein and mineral - into a mechanical masterpiece.</p>



<p>Further research will probe other species, life stages, and environmental stresses. Mixed-phase cartilage from hammerheads or deep-sea lantern sharks may reveal different configurations tuned to unique swimming styles or pressure regimes.</p>



<p>Each discovery will refine the emerging field of deep-sea biomimetics, where ancient adaptations inform tomorrow’s materials. </p>



<p>For engineers seeking to reconcile strength, flexibility, and damage tolerance, few tutors rival the blacktip shark. It has been perfected by 450 million years of relentless motion through saltwater and time.</p>



<p>The study is published in the journal <a href="https://pubs.acs.org/doi/10.1021/acsnano.5c02004" target="_blank" rel="noreferrer noopener"><em>ACS Nano</em></a>.</p>



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Shark skeletons could lead to technological innovations

Sharks have glided through oceans for more than 450 million...

<p>A massive exploration of ocean life has revealed 866 new species that most people never knew existed. This achievement ranks among the largest efforts ever to document organisms dwelling in some of the most secluded underwater zones.</p>



<p>Many surprises have surfaced from <a href="https://oceancensus.org/publications/press-release-the-ocean-census-discovers-over-800-new-marine-species/?ftag=YHF4eb9d17" target="_blank" rel="noreferrer noopener">these findings</a>, including a curious new guitar shark species. </p>



<p>This creature was first recorded at approximately 650 feet below the surface by <a href="https://mlml.sjsu.edu/research-faculty/david-ebert/" target="_blank" rel="noreferrer noopener">David Ebert</a>, the “Lost Shark Guy” from the Pacific Shark Research Center at Moss Landing Marine Laboratories (<a href="https://mlml.sjsu.edu/" target="_blank" rel="noreferrer noopener">MLML</a>).</p>



<h2 class="wp-block-heading" id="h-hidden-marine-species-among-ocean-life">Hidden marine species among ocean life</h2>



<p>“The ocean covers 71% of our planet, yet it is said that only around 10% of marine life has been discovered so far, leaving an estimated 1-2 million species still undocumented," said Executive Director <a href="https://oceancensus.org/team-member/mitsuyuku-unno/" target="_blank" rel="noreferrer noopener">Mitsuyuki Unno</a> of <a href="https://www.nippon-foundation.or.jp/en" target="_blank" rel="noreferrer noopener">The Nippon Foundation</a> representing the founding partner of the Ocean Census. "</p>



<p>"These latest findings demonstrate how international collaboration can advance our understanding of ocean biodiversity."</p>



<p>Experts say learning about unexplored species can spark fresh approaches to conservation. Documenting them quickly is critical since cataloguing can take over a decade, which creates risks for vulnerable marine <a href="https://www.earth.com/news/filter-feeders-transform-microplastics-into-a-bigger-threat/" target="_blank" rel="noreferrer noopener">creatures</a>.</p>



<h2 class="wp-block-heading" id="h-a-snail-with-hidden-value">A snail with hidden value</h2>



<p>A standout discovery involves the turrid <a href="https://www.earth.com/news/bright-yellow-margarita-snails-discovered-in-florida-keys/" target="_blank" rel="noreferrer noopener">gastropods</a> known as <em>Turridrupa magnifica</em>. It was found between about 650 and 1,600 feet in waters off New Caledonia and Vanuatu. </p>



<p>Scientists note these snails carry venomous barbs used to capture prey, and <a href="https://pubmed.ncbi.nlm.nih.gov/17932414/" target="_blank" rel="noreferrer noopener">related snail compounds</a> have inspired pain relief drugs, including some tested for <a href="https://www.earth.com/news/breakthrough-cancer-cells-have-a-molecular-switch-that-could-be-rewired-to-behave-normally/" target="_blank" rel="noreferrer noopener">cancer</a> treatment.</p>



<p>Its potential medical applications symbolize the practical significance of identifying new lifeforms. </p>



<p>Locating <a href="https://www.earth.com/news/new-species-of-tree-snake-with-completely-black-eyes-is-discovered/" target="_blank" rel="noreferrer noopener">rare species</a> can lead to breakthroughs in human health, especially if researchers can examine the biochemical secrets behind their survival.</p>



<h2 class="wp-block-heading" id="h-a-fresh-octocoral-in-the-maldives">A fresh octocoral in the Maldives</h2>



<p>A newly found <em>Octocoral genus</em> in the <a href="https://www.earth.com/news/drowning-mangroves-climate-change-is-pushing-nature-past-its-limits/" target="_blank" rel="noreferrer noopener">Maldives</a> drew excitement from specialists at the Maldives Marine Research Institute. </p>



<p>This is the first known record of its type in that area. <a href="https://www.abebooks.com/Shallow-Water-Octocorallia-West-Indian-Region-Manual/31967855712/bd" target="_blank" rel="noreferrer noopener">Octocorals</a> help shore up reef structures and create habitats for countless fish and invertebrates.</p>



<p>Additional research could clarify how these corals protect shorelines from erosion and benefit local fisheries. They highlight the functional roles that relatively unknown organisms can play in underwater <a href="https://www.earth.com/news/new-ecosystem-sea-creatures-never-before-seen-revealed-antarctica-iceberg-breakup/" target="_blank" rel="noreferrer noopener">ecosystems</a>.</p>



<h2 class="wp-block-heading" id="h-understanding-the-new-marine-species">Understanding the new marine species</h2>



<p>“Too many species remain in limbo for years because the process of formally describing them is too slow," stated <a href="https://oceancensus.org/team-member/prof-lucy-woodall/" target="_blank" rel="noreferrer noopener">Prof. Lucy Woodall</a>, Head of Science at <a href="https://oceancensus.org/" target="_blank" rel="noreferrer noopener">Ocean Census</a>.</p>



<p>"We urgently need to change that and adding the Species Discovery step gives us a way to rapidly start the process. Every new species - whether a shark or a sponge - deepens our understanding of marine ecosystems and the benefits they provide for the planet.” </p>



<p>Taxonomists are taking new steps to expedite this framework by adding interim documentation. The <a href="https://dataplatform.oceancensus.org/en" target="_blank" rel="noreferrer noopener">Ocean Census Biodiversity Data Platform</a> allows researchers and the public to see entries while more detailed scientific descriptions continue behind the scenes.</p>



<h2 class="wp-block-heading" id="h-refining-the-global-mission">Refining the global mission</h2>



<p>“We’ve pioneered new methods, forged key partnerships, established a global network of participating scientists, and overcome the hurdles of a truly global mission," said <a href="https://oceancensus.org/team-member/oliver-steeds-obe/" target="_blank" rel="noreferrer noopener">Oliver Steeds</a>, Director of the Ocean Census.&nbsp; </p>



<p>Steeds also suggests, "We are laying the groundwork to make large-scale species discovery a reality, but our impact will ultimately be determined by how this knowledge is used to support <a href="https://www.earth.com/news/marine-protected-areas-have-spillover-benefits-around-the-world/" target="_blank" rel="noreferrer noopener">marine protection</a>, climate adaptation, and <a href="https://www.earth.com/news/biodiversity-leaks-conservation-efforts-may-shift-harm-elsewhere/" target="_blank" rel="noreferrer noopener">biodiversity conservation</a>."</p>



<p>Leaders of the Ocean Census maintain that collaborative strategies are vital. Collective efforts from more than 400 institutions feed into this decentralized network. </p>



<p>By grouping different skill sets and resources, they cut the time required to identify new lifeforms in waters from the tropics to the icy poles.</p>



<h2 class="wp-block-heading" id="h-uniting-innovators-and-organizations">Uniting innovators and organizations</h2>



<p>“<a href="https://schmidtocean.org/">Schmidt Oc</a><a href="https://schmidtocean.org/" target="_blank" rel="noreferrer noopener">e</a><a href="https://schmidtocean.org/">an Institute</a> is proud to be a partner of the Ocean Census, whose strength lies in its vast network," said Executive Director of Schmidt Ocean Institute, <a href="https://schmidtocean.org/person/dr-jyotika-virmani/" target="_blank" rel="noreferrer noopener">Jyotika Virmani</a>.</p>



<p>"By uniting governments, philanthropic supporters, and leading marine research organizations, we can accelerate the discovery of ocean life at an unprecedented scale,” </p>



<p>Research institutes, philanthropic foundations, and government agencies are aligning to explore areas that have never been systematically sampled. </p>



<p>These partnerships allow scientists to map remote habitats with advanced tools, gather specimens with submersibles, and build shared databases for faster and more accurate species registration.</p>



<h2 class="wp-block-heading" id="h-looking-ahead-ocean-and-marine-life">Looking ahead: Ocean and marine life</h2>



<p>The campaign plans to keep expanding its scope. More expeditions and workshops are slated for 2025, stretching from the Pacific to the Indian and <a href="https://www.earth.com/news/carbon-storage-mystery-emerges-in-the-southern-ocean/" target="_blank" rel="noreferrer noopener">Southern Oceans</a>. </p>



<p>Their findings will funnel into the network’s biodiversity platform, reinforcing collective knowledge of hidden <a href="https://www.earth.com/news/oceans-cool-the-climate-more-than-previously-realized/" target="_blank" rel="noreferrer noopener">ocean</a> life.</p>



<p>Experts stress the importance of channeling these discoveries into actions that protect fragile habitats. </p>



<p>Once researchers confirm a species, that opens doors for environmental policies tailored to safeguard threatened populations or preserve essential ocean corridors.</p>



<p>New developments at the frontier of taxonomy also create opportunities for local communities. </p>



<p>Some of these <a href="https://www.earth.com/news/why-antarctic-waters-are-cooling-in-a-warming-world/" target="_blank" rel="noreferrer noopener">waters</a> serve as essential fishing grounds, so tracking new inhabitants can shed light on how to maintain long-term sustainability.</p>



<p>This study was published in the <a href="https://oceancensus.org/publications/press-release-the-ocean-census-discovers-over-800-new-marine-species/?ftag=YHF4eb9d17" target="_blank" rel="noreferrer noopener">Ocean Census</a>. </p>



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Guitar-shaped ray species, discovered for the first time, lives in the deep ocean

A massive exploration of ocean life has revealed 866 new...

<p>Peering over the forest-draped ridges of southwestern China, a scar nearly half a mile wide across yawns open, so sheer that light seems to drain straight into the earth. Xiaozhai Tiankeng, also known as the "Heavenly Pit," is the world's largest sinkhole.</p>



<p> Locals have spoken of Xiaozhai Tiankeng for centuries, yet it was only “discovered” by the wider world in 1994 when a team of British cavers stumbled on its hidden maw.</p>



<p>Measured from rim to floor, the Xiaozhai Heavenly Pit plunges about 2,172 feet - deeper than a stack of six Statues of Liberty - and encloses roughly 4.2 billion cubic feet of space. </p>



<p>Those numbers secure its place as the planet’s deepest and largest known sinkhole, a title it wears with quiet, vertigo-inducing confidence.</p>



<h2 class="wp-block-heading" id="h-xiaozhai-tiankeng-a-hidden-giant">Xiaozhai Tiankeng - a hidden giant</h2>



<p>Geologists now read the sinkhole’s striped limestone walls like pages in an epic timeline. Rainwater, slightly acidic after mingling with soil carbon dioxide, seeped through fractures in Triassic-age rock for some 128,000 years. </p>



<p>Bit by bit, it hollowed out caverns below <a href="https://en.wikipedia.org/wiki/Fengjie_County" target="_blank" rel="noreferrer noopener">Fengjie County</a>, until the ceiling finally collapsed and birthed the chasm seen today.</p>



<p>Because the limestone lies high above sea level and is free of clay impurities, water could tunnel unimpeded, carving passages that still channel underground streams. </p>



<p>The Xiaozhai Tiankeng stands as the textbook example of karst topography - what happens when karst processes are given perfect working conditions - and plenty of monsoon rain.</p>



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



<p><a href="https://www.sciencedirect.com/science/article/pii/S2589471424000202" target="_blank" rel="noreferrer noopener">Karst topography</a> forms when water slowly eats away at soft, soluble rocks like limestone, dolomite, or gypsum. As rainwater seeps into the ground, it picks up carbon dioxide and turns slightly acidic. That weak acid reacts with the rock, gradually wearing it down.</p>



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/05/sinkholes_karst-topography_diagram-illustration_annotated_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2025/05/sinkholes_karst-topography_diagram-illustration_annotated_1s.webp" alt="Water shapes karst landscapes by slowly dissolving soft, soluble rocks like limestone. Over time, this natural process carves out striking features - think sinkholes, hidden caves, and winding underground rivers. You’ll often find these dramatic terrains in rainy regions rich in carbonate rock. Click image to enlarge." class="wp-image-1970449"/></a><figcaption class="wp-element-caption"><em>Water shapes karst landscapes by slowly dissolving soft, soluble rocks like limestone. Over time, this natural process carves out striking features - think sinkholes, hidden caves, and winding underground rivers. You’ll often find these dramatic terrains in rainy regions rich in carbonate rock. Click image to enlarge.</em></figcaption></figure>



<p>Over time, the land above starts to sag and collapse, creating sinkholes, disappearing streams, and vast cave systems below the surface. It’s a quiet, powerful transformation that reshapes the landscape from the inside out.</p>



<h2 class="wp-block-heading" id="h-how-xiaozhai-tiankeng-got-its-name">How Xiaozhai Tiankeng got its name</h2>



<p>Chinese researchers classify this colossus as a tiankeng, a term reserved for sinkholes at least 328 feet deep and wide, each harboring a river at its base. </p>



<p>The word translates variously as “heavenly pit” or “sky hole,” both fitting nods to the feeling one gets while peering over the edge. Of the 75 such features documented worldwide, about 50 cluster inside China’s humid karst belts.</p>



<p>The Xiaozhai example dwarfs its peers: it stretches roughly 1,676 to 2,054 feet long and 984 to 1,762 feet across, dimensions that defy easy comparison yet satisfy every benchmark geologists set for these rare landforms.</p>



<h2 class="wp-block-heading" id="h-long-layered-steep-descent">Long, layered, steep descent</h2>



<p>Two enormous “bowls” stack inside the chasm, each dropping more than 984 feet before giving way to the next terrace. </p>



<p>After heavy summer storms, a temporary waterfall pours over the rim and ribbons down the vertical walls, then vanishes into the stone. </p>



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/05/sinkhole_worlds-largest_Xiaozai-Tiankang_bottom-view_Credit-Research-Gate_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2025/05/sinkhole_worlds-largest_Xiaozai-Tiankang_bottom-view_Credit-Research-Gate_1s.webp" alt="View along the floor of the Qinlong Tiankeng, towards the natural bridge at its western end, in the Wulong Sanqiao Park. Credit: ResearchGate" class="wp-image-1970451"/></a><figcaption class="wp-element-caption"><em>View along the floor of the Qinlong Tiankeng, towards the natural bridge at its western end, in the Wulong Sanqiao Park. Click image to enlarge. Credit: ResearchGate</em></figcaption></figure>



<p>Where the stream briefly reappears, it leaps in a single 151-foot plunge that echoes through the darkness below.</p>



<p>Scrambling down is a workout: concrete stairways cling to corners of the cliff, but many scientists still rope in, carrying sensors and sampling kits on their harnesses. </p>



<p>The sense of scale - walls so high the sky shrinks to a blue rectangle - never quite fades.</p>



<h2 class="wp-block-heading" id="h-life-inside-xiaozhai-tiankeng">Life inside Xiaozhai Tiankeng</h2>



<p>Sunlight weakens but never disappears, nurturing a green haze of ferns, mosses, and towering ginkgo biloba trees. </p>



<p>Biologists have counted 1,285 plant and animal species in this natural greenhouse, including the elusive clouded leopard, whose total wild population is thought to number fewer than 10,000. </p>



<p>Dense humidity and steady temperatures create a pocket climate unlike anything on the surrounding plateau.</p>



<p>Winged insects flit among orchids; amphibians breed in clear pools; vines cling to walls slick with mist. </p>



<p>Each tier supports its own community, separated by the same height difference that splits mountain life into bands. To ecologists, the pit is a ready-made laboratory for studying evolution in vertical space.</p>



<h2 class="wp-block-heading" id="h-a-river-runs-through-it">A river runs through it</h2>



<p>Near the foot of the second bowl, the Difeng cave yawns open, swallowing a crystal stream that has already traveled 5.3 miles underground. </p>



<p>The water’s final above-ground act is that 151-foot curtain, after which it threads the darkness beneath the sinkhole and resurfaces downstream at the cliffs of the Migong River. </p>



<p>Flow-rate monitors reveal seasonal surges that match regional rainfall, tying surface weather to hidden hydrology.</p>



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/05/sinkhole_worlds-largest_Xiaozai-Tiankang_Credit-Research-Gate_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2025/05/sinkhole_worlds-largest_Xiaozai-Tiankang_Credit-Research-Gate_1s.webp" alt="Xiaozhai Tiankeng seen from the southern rim; the path down the stone steps is obscured by trees and shrubs-it curves round to the right and descends the steep debris fan inside the lower pit. Credit: ResearchGate" class="wp-image-1970447"/></a><figcaption class="wp-element-caption"><em>Xiaozhai Tiankeng seen from the southern rim; the path down the stone steps is obscured by trees and shrubs-it curves round to the right and descends the steep debris fan inside the lower pit. Click image to enlarge. Credit: ResearchGate</em></figcaption></figure>



<p>Mapping that labyrinth has never been easy. Speleologists tried five times in a decade to trace the torrent from end to end; each expedition turned back amid roar and spray, equipment battered by sudden rises in water level. </p>



<p>The cave remains one of China’s least charted river systems, a reminder that even in the GPS era some coordinates resist tidy lines.</p>



<h2 class="wp-block-heading" id="h-karst-topography-and-xiaozhai-tiankeng">Karst topography and Xiaozhai Tiankeng</h2>



<p>Field teams from Chongqing’s Institute of Karst Geology, often joined by overseas colleagues, now lower radar probes, deploy microclimate loggers, and sample sediments for isotopic clocks that refine the sinkhole’s birth date. </p>



<p>Their findings feed global climate models and offer clues to safeguarding groundwater in limestone regions where pollution can spread in hours.</p>



<p>Yet the pit keeps its mystique. Nearby villagers swap tales of dragons curling inside the void or celestial doors hidden behind the waterfall. </p>



<p>Trekkers on the steep trail say the silence at the bottom feels otherworldly, broken only by dripping water and the occasional flap of a bat. </p>



<p>Maybe that mix of hard data and lingering legend is why the Xiaozhai Tiankeng continues to draw scientists, adventurers, and curious travelers alike - each hoping to understand, if only for a moment, how water, rock, and time conspired to open a doorway straight through the Earth’s surface.</p>



<p>This story was adapted from a report by the BBC, <a href="https://www.bbc.com/reel/video/p0crc7bb/china-s-huge-and-mysterious-xiaozhai-tiankeng-sinkhole" target="_blank" rel="noreferrer noopener">which you can watch here…</a></p>



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World’s largest sinkhole showcases the power and beauty of nature

Peering over the forest-draped ridges of southwestern China, a scar...


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