Today's Image of the Day from NASA Earth Observatory features a satellite view of retreating glaciers in Alaska, where meltwater is rapidly expanding glacial lakes. The image was captured on August 4, 2024 by the Landsat 8 satellite.



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



Image Credit: NASA Earth Observatory



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Retreating glaciers and expanding meltwater lakes in Alaska

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

Today's Image of the Day from NASA Earth Observatory features the Gobi Altai Mountains and neighboring plains covered in snow and illuminated by sunlight. 



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



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



“Late-afternoon sunlight casts long shadows of mountain peaks onto the plains below. Numerous steep gullies cut into the massif, or mass of mountains, whose rugged appearance contrasts with the flat plains stretching along the top of the image,” said <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA</a>. “The plains are a semidesert grassland, or steppe, which provides pasture for livestock herders in the region.”



“The grassland surrounding the massif is classified by scientists as a cold semidesert. At an elevation of about 1,250 meters, annual temperatures are much lower there than in the mountains. The highest peak in the massif, Ikh Bogd (also known as Tergun Bogd), reaches nearly 4,000 meters.”&nbsp;



According to NASA, the climate on the peaks is classified as a polar tundra because the average annual temperature is below freezing. "Asia’s main tundra zone is located in Siberia, along the coast of the Arctic Ocean, 2,800 kilometers (1,750 miles) to the north.”



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



Harsh <a href="https://www.earth.com/news/why-winters-are-getting-colder-while-world-is-getting-warmer/" target="_blank" rel="noreferrer noopener">winters</a> in Mongolia, locally known as "dzud," pose significant challenges for livestock and the herders who depend on them for their livelihood. These winters can be particularly severe, characterized by extreme cold, heavy snowfall, and ice, which can block access to grazing grounds, leaving animals without enough food.&nbsp;



The cold temperatures and nutritional shortages result in high mortality rates among livestock, which are crucial to the Mongolian economy and the nomadic lifestyle of many of its people.



The impact of these harsh winters extends beyond immediate animal welfare. As <a href="https://www.earth.com/news/bacteria-in-livestock-are-major-drivers-of-antibiotic-resistance/" target="_blank" rel="noreferrer noopener">livestock</a> numbers dwindle, herders face financial hardships, and the ripple effects can be felt throughout the entire community.&nbsp;



To combat these challenges, various strategies have been employed, including the development of better forecasting and early warning systems, the stockpiling of fodder, and improved veterinary care. These measures aim to strengthen the resilience of herding communities and ensure the survival of their livestock during Mongolia's most challenging seasons.



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



Mongolia is renowned for its diverse wildlife, adapted to its unique landscapes ranging from vast steppes to rugged <a href="https://www.earth.com/news/mountains-both-carbon-sinks-and-carbon-sources/" target="_blank" rel="noreferrer noopener">mountains</a> and arid deserts. Among the most iconic species is the Bactrian camel, native to the region and crucial to nomadic herders.&nbsp;



The resilient Mongolian horse, integral to local culture, is celebrated for its endurance across the vast, open landscapes. Predators such as the snow leopard roam the high altitudes, playing a key role in the ecosystem, while the elusive Gobi bear survives in the sparse vegetation of the Gobi Desert.



The steppes are home to the fast-moving Mongolian gazelle and the critically endangered saiga antelope, known for its distinctive nose. The mountains support populations of argali sheep, the world's largest wild sheep, and the ibex, which has mastered the art of navigating rocky terrains. 



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



“Part of a small dry lake appears in the top left of the image. In wetter years, water from this lake feeds Orog Lake (also photographed by astronauts), out of frame to the upper right. This and other nearby lakes are part of the Valley of Lakes waterfowl conservation habitat, protected as a Ramsar site,” noted NASA.



The Valley of Lakes is known for its expansive <a href="https://www.earth.com/news/the-potential-of-tidal-wetlands-as-blue-carbon-ecosystems/" target="_blank" rel="noreferrer noopener">wetlands</a> and diverse ecosystems that support a variety of bird species, especially migratory waterfowl. This area serves as a crucial stopover for birds during their migration periods, providing them with essential resources such as food and shelter.&nbsp;



The conservation efforts in the Valley of Lakes focus on maintaining and restoring these <a href="https://www.earth.com/news/coastal-wetlands-are-inching-closer-to-extinction-as-the-world-heats-up/" target="_blank" rel="noreferrer noopener">wetlands</a> to ensure they continue to offer a safe haven for waterfowl. These efforts include controlling invasive plant species that threaten the natural vegetation and managing water levels to create optimal conditions for bird populations.&nbsp;



Education and community involvement are also key components of the conservation strategy, aiming to raise awareness about the importance of these habitats and encourage sustainable practices that help protect the local wildlife.



Image Credit: NASA Earth Observatory&nbsp;



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Mountain peaks and plains of central Mongolia 

Today's Image of the Day from the European Space Agency features the barred spiral galaxy NGC 1559, located around 35 million light-years away in the southern constellation Reticulum. The image was captured by the James Webb Space Telescope. 



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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Spiral galaxy NGC 1559 is a loner in outer space

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

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



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



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



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



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



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



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



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



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



Blue giants are massive stars that have left the main sequence phase of stellar evolution and are burning helium or heavier elements in their cores. These stars are known for their short lifespans relative to smaller stars due to their rapid consumption of nuclear fuel.



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



<a href="https://www.earth.com/news/dark-stars-scientists-discover-a-new-type-of-star-powered-by-dark-matter/" target="_blank" rel="noreferrer noopener">Stars</a> like HD 101274 are important for astronomers because they help in studying the properties of stellar populations in clusters and the dynamics of stellar evolution in different environments. 



The spectral and photometric observations of such stars can provide valuable insights into the characteristics of their atmospheres, internal structures, and the processes occurring within and around them.



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



One of the most interesting aspects of NGC 3783 is that it harbors an active galactic nucleus, meaning its central region is exceptionally luminous, likely due to the presence of a supermassive black hole. This black hole is actively accreting material, which emits a substantial amount of radiation as it spirals inward and heats up.



The galaxy is particularly known for its bright central region and has been studied extensively in the ultraviolet and X-ray light spectra to understand better the properties of the accretion disk around the black hole and the complex dynamics of the material surrounding it. These studies are crucial for understanding the physics of active galactic nuclei and the role they play in <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">galaxy evolution</a>.



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



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



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



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



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



Studying groups like the NGC 3783 group helps astronomers understand how <a href="https://www.earth.com/news/ceers-2112-ancient-galaxy-looks-strikingly-similar-to-ours/" target="_blank" rel="noreferrer noopener">galaxies</a> evolve together in a common gravitational environment, offering insights into the dynamics and evolution of structures on cosmic scales. 



Image Credit: ESA/Hubble &amp; NASA



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Luminous galaxy NGC 3783 and a blue giant star

Today's Image of the Day from NASA Earth Observatory features Cyclone Chido, an intense tropical cyclone that caused unprecedented devastation across Southeast Africa in December 2024.



On December 14, Chido struck the islands of Mayotte with wind speeds exceeding 200 km/h (124 mph) and gusts over 225 km/h (140 mph), marking it as the most powerful storm to hit the French territory in at least 90 years.&nbsp;



The <a href="https://www.earth.com/news/fast-moving-tropical-cyclones-are-becoming-more-powerful/" target="_blank" rel="noreferrer noopener">cyclone</a> ultimately made three landfalls - all with winds equivalent to those of a Category 4 tropical cyclone. According to media reports, authorities in Mayotte fear that hundreds and possibly thousands of people have died.



<h2 class="wp-block-heading" id="h-rapid-intensification-of-chido">Rapid intensification of Chido</h2>



“Chido formed in the southeastern Indian Ocean on December 5, 2024. The disturbance rapidly intensified before hitting the Mauritian islands of Agaléga on December 11. The next day, the cyclone peaked in intensity, with sustained winds of about 250 kilometers (155 miles) per hour - equivalent to a strong Category 4 hurricane on the Saffir-Simpson wind scale,” noted <a href="https://earthobservatory.nasa.gov/images/153708/cyclone-chido-pummels-mayotte" target="_blank" rel="noreferrer noopener">NASA</a>.&nbsp;&nbsp;



“According to the Joint Typhoon Warning Center, Cyclone Chido continued to move west in an environment favorable for sustaining storms. That included warm <a href="https://www.earth.com/news/ocean-warming-has-nearly-doubled-in-the-last-decade/" target="_blank" rel="noreferrer noopener">sea surface temperatures</a> of up to 29 degrees Celsius (84 degrees Fahrenheit) and low vertical wind shear.



<h2 class="wp-block-heading" id="h-devastation-of-cyclone-chido-nbsp">Devastation of Cyclone Chido&nbsp;</h2>



The cyclone obliterated entire neighborhoods, particularly in hillside shantytowns inhabited by undocumented migrants. Official reports confirm at least 31 fatalities and thousands of injuries - though the actual death toll may be significantly higher.&nbsp;



The destruction in Mayotte's capital, Mamoudzou, has left approximately 100,000 people homeless. The aftermath has been characterized by a lack of visible assistance from authorities, with residents relying on community support amid concerns over hunger, disease outbreaks, and lawlessness.&nbsp;



<h2 class="wp-block-heading" id="h-landfall-in-mozambique-nbsp">Landfall in Mozambique&nbsp;</h2>



Following its impact on Mayotte, Chido continued westward, making landfall in Mozambique on December 15 near the city of Pemba as a strong Category 4-equivalent intense tropical cyclone.&nbsp;



The storm resulted in at least 34 deaths and 43 injuries across three northern provinces. In neighboring Malawi, Chido claimed two lives.&nbsp;



The cyclone's ferocity, fueled by warmer ocean temperatures attributed to climate change, has raised concerns about the increasing frequency and <a href="https://www.earth.com/news/coastal-hurricanes-are-intensifying-faster-due-to-climate-change/" target="_blank" rel="noreferrer noopener">intensity</a> of such storms in the region.&nbsp;



<h2 class="wp-block-heading" id="h-recovery-efforts-and-vulnerable-communities-nbsp">Recovery efforts and vulnerable communities&nbsp;</h2>



The crisis has highlighted the vulnerabilities of affected regions, particularly Mayotte, which faces challenges of poverty, overcrowding, and inadequate infrastructure.&nbsp;



The lack of preparedness and insufficient emergency response have drawn criticism, highlighting the need for improved disaster management and investment in resilient infrastructure to mitigate the impacts of future climate-induced disasters.&nbsp;



In response to the disaster, French President Emmanuel Macron is scheduled to visit Mayotte, and relief efforts are underway, including the arrival of a ship carrying 180 tons of aid.&nbsp;



However, the scale of destruction and ongoing challenges in delivering assistance to remote and inaccessible areas continue to impede recovery efforts.&nbsp;



<h2 class="wp-block-heading" id="h-climate-fueled-intensification-of-cyclones-nbsp">Climate-fueled intensification of cyclones&nbsp;</h2>



The <a href="https://www.earth.com/news/the-rising-impact-of-tropical-cyclones-in-a-warming-world/" target="_blank" rel="noreferrer noopener">intensification of cyclones</a> due to climate change is a significant and concerning phenomenon. As global temperatures rise, warmer ocean waters provide the energy that fuels tropical cyclones, making them stronger and more destructive.&nbsp;



Higher <a href="https://www.earth.com/news/pacific-ocean-temperatures-highest-in-650-years-greatly-harming-coral-reefs/" target="_blank" rel="noreferrer noopener">sea surface temperatures</a> lead to increased evaporation, which adds more moisture to the atmosphere. This moisture can enhance the rainfall associated with cyclones, increasing the risk of flooding.&nbsp;



Additionally, rising sea levels, driven by the melting of polar ice caps and thermal expansion of seawater, exacerbate storm surge impacts, causing more extensive and severe coastal flooding during cyclonic events.



Changes in atmospheric conditions also play a role. While climate change may not increase the overall frequency of cyclones, it is likely to shift the distribution and intensity of these storms. For instance, studies suggest that a larger proportion of cyclones are reaching the most intense categories.&nbsp;



Furthermore, slower-moving cyclones, a trend linked to weakened steering currents, can linger longer over vulnerable areas, compounding the damage with prolonged heavy rainfall and strong winds.



These changes in cyclone behavior present challenges for disaster preparedness and response. Coastal communities, particularly in low-lying regions, are becoming increasingly vulnerable to the compounded impacts of more powerful storms, highlighting the urgent need for climate mitigation and adaptation strategies.



The image was captured by the VIIRS (Visible Infrared Imaging Radiometer Suite) on the NOAA-20 satellite, about three hours after the storm made landfall.



Image Credit: NASA Earth Observatory&nbsp;



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Cyclone Chido’s path of destruction: A climate wake-up call

Mexican,Ajolote,Or,Ambystoma,Mexicanum,Or,Old,Amphibian

You may have come across axolotls - those smiling amphibians with pink, plume-like gills - in pet stores, as plush toys, or even featured in video games. 



Yet, their growing presence in popular culture has emerged just as the wild population of this remarkable species faces critical endangerment.



<h2 class="wp-block-heading" id="h-axolotls-have-become-a-cultural-icon">Axolotls have become a cultural icon</h2>



James Monaghan, a biology professor at <a href="https://www.northeastern.edu/" target="_blank" rel="noreferrer noopener">Northeastern University</a>, has long studied axolotls and their extraordinary regenerative capabilities. “Axolotls have just exploded in popularity the past couple of years,” he said. 



Monaghan recalled that when he began his PhD studies, the general public had little idea what an axolotl was.&nbsp;



“No one knew in the general public what an axolotl was, so I'd have to explain,” he remembered, contrasting that with today’s situation: “Now I just can say, 'Oh, I work on axolotls,' and everyone just lights up.”



Monaghan noted that young people, in particular, have been drawn to axolotls, most likely due to their aesthetic charm.&nbsp;



“They're pink, they have feathers,” he said. “Well, they don't really have feathers, but their gills are feathery. They have a constant little smile on their face. If you were to create a cute animal that you couldn't think existed naturally, it's kind of the axolotl. It's got the vibes of a dragon, but a nice dragon.”



<h2 class="wp-block-heading" id="h-from-ancient-roots-to-gaming-stardom">From ancient roots to gaming stardom</h2>



The axolotl is no newcomer to cultural significance. “It's named after an Aztec god, Xolotl,” Monaghan explained, referencing its deep ties to Mexican heritage. Initially found in Lake Xochimilco near Mexico City, this <a href="https://www.earth.com/news/over-40-of-amphibians-face-extinction-due-to-escalating-climate-threats/" target="_blank" rel="noreferrer noopener">amphibian</a>’s recent surge in popularity has transcended borders.



Its presence in mainstream culture can be traced in part to its introduction into the world of Minecraft, a <a href="https://www.earth.com/news/how-violent-video-games-impact-the-human-mind/" target="_blank" rel="noreferrer noopener">video game</a> of immense popularity.&nbsp;



“Minecraft is enormously popular for young players. The game allows for social play, exploration, sandbox style play where you can make anything,” said Northeastern assistant professor of computer science Alexandra To. By featuring axolotls, the game inspires curiosity and a desire to learn.&nbsp;



“Minecraft provides players great intrinsic motivation to discover more about any new elements that are added to the game,” To added.



In some cases, this might involve players constructing elaborate environments to house every in-game creature. “As my own partner did, in embarking on a project to create an enormous zoo with every in-world animal,” she remarked.



Monaghan suggests that axolotls may have also influenced other media. “I don't know if it's actually the motivation for 'How To Train Your Dragon,'” he said, pointing out that the character Toothless resembles an axolotl with its perpetual smile and ear-like flaps suggesting feathery gills.



<h2 class="wp-block-heading" id="h-scientific-significance-of-axolotls-nbsp">Scientific significance of axolotls&nbsp;</h2>



While their looks and cultural presence have captured public affection, axolotls are scientifically remarkable as well. Their regenerative powers extend beyond limbs. Monaghan’s lab has found that they can regenerate a large portion or their lung.&nbsp;



“They are notoriously resistant to <a href="https://www.earth.com/news/ai-is-the-next-frontier-in-cancer-treatment/" target="_blank" rel="noreferrer noopener">cancers</a>, never get infections after an injury,” he said, and can live for up to two decades - qualities that have made them valuable subjects of study for generations.



“Axolotls are the longest standing lab animal of any animal, longer than flies, longer than worms, longer than mice,” Monaghan said. First collected in 1864 from Lake Xochimilco, their initial appeal stemmed from their unusual, fully aquatic life cycle.&nbsp;



Over time, they became critical for studies on genetics, development, and <a href="https://www.earth.com/news/study-sheds-light-on-the-pathways-of-plant-regeneration/" target="_blank" rel="noreferrer noopener">regeneration</a>. With modern genetic tools like CRISPR, researchers can now pinpoint which genes drive their regenerative capabilities.



All lab and pet axolotls today descend from that original 19th-century population, and this lineage includes the distinct white axolotl familiar to fans worldwide.&nbsp;



“The white axolotl, which seems to be pretty much every stuffed animal that's out there, is actually a mutation of a single animal that was collected in 1864,” Monaghan explained. “You can get color variants, but the pink variety - that's from one founding animal.”



<h2 class="wp-block-heading" id="h-a-species-in-peril">A species in peril</h2>



As axolotls capture hearts around the globe, their wild counterparts hover on the brink of extinction. Once, locals could easily scoop them from Lake Xochimilco’s waters.&nbsp;



“Maybe up to the 1950s, you could put a net in Lake Xochimilco, the canal system, and pull up adult axolotls. And then every decade since, it's just crashed,” Monaghan said. “To the point now that they're critically endangered, and it takes weeks to even find one.”



They are exquisitely sensitive to environmental changes. “Being an amphibian, you're at the whim of your environment. You're taking in everything through your water,” he explained.&nbsp;



Climate change warms these waters, making survival harder, while pollution and introduced species further destroy fragile habitats and devour axolotl eggs.



<h2 class="wp-block-heading" id="h-the-challenge-of-conservation">The challenge of conservation</h2>



Given their success in captivity, one might assume we could simply return these lab and pet lineages to Lake Xochimilco. But it’s not that simple.&nbsp;



“It's probably not the best strategy to take a species that's been inbred since 1864 and reintroduce it into its natural habitat,” Monaghan said.&nbsp;



The modern axolotl has adapted to controlled conditions, while its original environment has changed drastically.&nbsp;



“We can't take the current axolotl and put it into the environment in Mexico City and expect them to thrive the same way as the original collection in 1864. The environment's changed, but the animals themselves have changed.”



Still, rising awareness may help efforts to protect the axolotl’s wild habitat. According to To, the team behind Minecraft has embraced conservation as part of its mission.&nbsp;



“Mojang has been pretty transparent about conservation as one of their core values,” she explained. “The inclusion of axolotls and their in-game rareness mirroring their real-world endangered status is a fantastic example of how game mechanics can reinforce educational messages.”



Monaghan is involved as well, serving on the advisory board of the Ambystoma Genetic Stock Center to support both scientific understanding and conservation. “Those direct efforts could really go a long way toward saving the axolotl,” he said.



All this attention suggests that the axolotl’s time has arrived. “All of a sudden, it seems to be absolutely everywhere,” Monaghan said.&nbsp; Yet, for all the joy and fascination these creatures provide, the work to secure their future in the wild is only just beginning.



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Axolotls have exploded in popularity, but they are also fighting extinction

You may have come across axolotls - those smiling amphibians...

Ants are capable of amazing feats, such as moving objects many times their size. A team of researchers in South Korea has introduced a swarm of magnetic robots that can replicate the extraordinary abilities of ants - and take them even further.



These tiny marvels aren't just mimicking nature; they're set to revolutionize how we approach complex tasks, from medical applications to industrial solutions.



<h2 class="wp-block-heading" id="h-tiny-robots-for-big-tasks">Tiny robots for big tasks</h2>



Researchers at <a href="https://www.hanyang.ac.kr/web/eng" target="_blank" rel="noreferrer noopener">Hanyang University</a> in Seoul, South Korea, have replicated the power of a colony of <a href="https://www.earth.com/news/ants-are-now-using-cars-to-travel-spread-to-new-locations/" target="_blank" rel="noreferrer noopener">ants</a> through an army of microbots. 



These tiny, magnetic robots can work together to perform tasks that would be impossible for a single robot. Peak performance by the microbots was observed when they were grouped in high aspect ratio assemblies.



These microbot armies proved capable of scaling obstacles five times their own length. They could even leap over obstacles one by one, like a sprinter jumping over a hurdle.



<h2 class="wp-block-heading" id="h-mighty-microbots-in-action">Mighty microbots in action</h2>



Picture a battalion of 1,000 microbots forming a raft that <a href="https://www.earth.com/news/microrobots-tested-as-clean-up-crew-for-polluted-waters/" target="_blank" rel="noreferrer noopener">floats on water</a>. This synthetic raft could wrap itself around an object like a pill that weighs in at a whopping 2,000 times the weight of a single microbot.



The raft allowed the microbots to "transport" the pill through a liquid medium. But their usefulness isn't limited to water-based tasks.



On dry land, the microbots could also transport cargo that was 350 times heavier than each individual bot.



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<h2 class="wp-block-heading" id="h-collaborative-efforts-to-overcome-obstacles">Collaborative efforts to overcome obstacles</h2>



Inspiration for the design of the microbots was drawn from ants, which are known for their collaborative efforts to overcome obstacles and ensure their <a href="https://www.earth.com/news/ant-colonies-behave-like-neural-networks-when-making-decisions/" target="_blank" rel="noreferrer noopener">collective survival</a>.



Just like ants, these robots can perform their programmed tasks despite their individual failures, eventually achieving the goal through collective effort.



"Swarm robotics has emerged as a promising methodology for accomplishing complicated tasks through collective behavior of multiple robots," wrote the researchers.



"A key feature of swarm robotics is fault tolerance: while a single robot or multiple robots in a swarm may fail to complete an allocated mission, other robots continue to perform their programmed motions until the mission succeeds."&nbsp;



<h2 class="wp-block-heading" id="h-innovation-in-robot-design">Innovation in robot design</h2>



Instead of using a conventional <a href="https://www.earth.com/news/ai-can-design-and-build-walking-robots-in-seconds/" target="_blank" rel="noreferrer noopener">robot design</a>, the team opted for cube-shaped microbots.



The change in shape allowed a larger surface area - the entire face of each cube - to make contact. This enabled stronger magnetic attractions between the microbots.



Each of these microbots stands only 600 micrometers tall and contains ferromagnetic neodymium-iron-boron (NdFeB) particles. This unique design allows them to respond to magnetic fields and interact with their fellow <a href="https://www.earth.com/news/robots-cannot-outrun-animals-but-theyre-evolving-faster/" target="_blank" rel="noreferrer noopener">robots</a>.



Manipulating the angle at which these microbots were magnetized resulted in the formation of different configurations. 



According to study co-author Jeong Jae Wie, a cost-effective mass-production method involving onsite replica molding and magnetization was developed to ensure uniform geometry and consistent performance.



<h2 class="wp-block-heading" id="h-future-of-microbot-swarms">Future of microbot swarms</h2>



Despite the promising results, there are still improvements to be made. 



Although the microbots can climb, throw things over an obstacle and lift objects, they currently require external magnetic control and lack the ability to navigate independently in complex spaces such as actual narrow arteries.



However, upcoming research aims to enhance the autonomy level of these microbot swarms, focusing on real-time feed control of their movements and trajectories.



The work of the South Korean scientists captures the beauty of innovation at its finest - turning the ordinary into extraordinary.



As we watch the future of medical technology unfold, one thing is clear - these mighty microbots are just the beginning.



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



While the magnetic microbots are making waves in medical technology, their potential applications extend far beyond the confines of healthcare.



The tiny robots could revolutionize industries such as environmental cleanup and manufacturing.



For instance, their ability to form rafts and transport objects could be adapted to help collect microplastics in oceans or deliver precise doses of chemicals in agriculture.



Additionally, their magnetic responsiveness makes them ideal candidates for assembling intricate components in electronics or even assisting in delicate tasks like repairing machinery in hard-to-reach areas.



Future advances in microbot autonomy could enable them to navigate complex environments independently, opening doors to breakthroughs in swarm-based logistics systems, disaster response technologies, and more.



The full study was published in the journal <a href="https://linkinghub.elsevier.com/retrieve/pii/S2666998624005830" target="_blank" rel="noreferrer noopener">Device</a>.



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Magnetic microbots can replicate the extraordinary abilities of ants

Ants are capable of amazing feats, such as moving objects...

It is a fascinating fact that a swirl of stars, light-years away from us, shares an uncanny resemblance to our home galaxy, the Milky Way.



A group of astronomers has stumbled upon a galaxy in the making that appears to be a mirror image of what our Milky Way might have resembled during its early stages.



<h2 class="wp-block-heading" id="h-firefly-sparkle-and-the-milky-way">Firefly Sparkle and the Milky Way </h2>



Nestled among the cosmos, this nascent galaxy, known as the "Firefly Sparkle," presents an awe-inspiring spectacle. Its unique similarity to a fledgling Milky Way has sparked curiosity among astronomers worldwide.



What makes this discovery even more interesting is the striking timeframe in which the galaxy seems to have come into existence - a mere 600 million years after the <a href="https://www.earth.com/news/new-observations-disprove-big-bang-theory-universe-began-tired-light-theory/" target="_blank" rel="noreferrer noopener">Big Bang</a>, the cosmic event that created the universe as we know it.



This is around the same era that our own galaxy started to form, which adds an additional layer of fascination.



The splendor of the Firefly Sparkle is vividly showcased through images that have been captured by NASA's James Webb Space Telescope.



The images reveal the spectacular <a href="https://www.earth.com/news/stunning-star-clusters-captured-in-the-extreme-outskirts-of-the-milky-way/" target="_blank" rel="noreferrer noopener">clusters of stars</a> that form the galaxy, each twinkling into existence at different periods. This multifarious formation is another attribute that the Firefly Sparkle shares with the Milky Way.



<h2 class="wp-block-heading" id="h-the-significance-of-the-discovery">The significance of the discovery</h2>



Study co-lead author Professor Lamiya Mowla, a distinguished astronomer at <a href="https://www.wellesley.edu/" target="_blank" rel="noreferrer noopener">Wellesley College</a>, emphasized the importance of the discovery.



"These remarkable images give us an unprecedented picture of what our own <a href="https://www.earth.com/news/runaway-star-j1249-36-spotted-trying-to-escape-our-milky-way-galaxy/" target="_blank" rel="noreferrer noopener">galaxy</a> might have looked like when it was being born," said Professor Mowla.



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Adding to the significance of the discovery, the size of the Firefly Sparkle mirrors the estimated mass of the Milky Way during its early developmental stages.



This feature sets the newly found galaxy apart from other celestial bodies detected in the same era, which are considerably larger in mass.



"By examining these photos of the Firefly Sparkle, we can better understand how our own Milky Way took shape," explained Professor Mowla.



<h2 class="wp-block-heading" id="h-evolution-of-galaxies-in-the-early-universe">Evolution of galaxies in the early universe</h2>



The mission of observing and understanding the structure and evolution of astronomical bodies in the early universe is of paramount importance. 



This type of research requires a deep investigation into the development of stars, star clusters, galaxies, and galaxy clusters in the early universe and their transformation over time.



"I didn't think it would be possible to resolve a galaxy that existed so early in the <a href="https://www.earth.com/news/webb-telescope-confirms-hubble-constant-our-understanding-of-universe-expansion-very-wrong/" target="_blank" rel="noreferrer noopener">universe</a> into so many distinct components, let alone find that its mass is similar to our own galaxy's when it was in the process of forming," said Professor Mowla.



The tiny Firefly Sparkle galaxy, with its wide array of star formation stages, is shedding new light on our own Milky Way and its past. The images will serve as the basis for extensive study and learning for years to come.



<h2 class="wp-block-heading" id="h-firefly-sparkle-and-galaxy-formation">Firefly Sparkle and galaxy formation</h2>



The discovery of the Firefly Sparkle is not just a marvel in itself but also a foundation for unraveling the broader mysteries of galaxy formation and evolution.



By analyzing its unique star clusters and mass distribution, astronomers can trace the intricate processes that likely occurred during the Milky Way's infancy. 



These findings allow scientists to refine existing models of <a href="https://www.earth.com/news/massive-galactic-explosion-provides-clues-about-galaxy-evolution/" target="_blank" rel="noreferrer noopener">galaxy evolution</a>, and offer a clearer timeline of how cosmic structures transitioned from chaotic gas clouds to the organized systems we see today.



Moreover, the Firefly Sparkle provides a rare opportunity to study star formation in an environment untouched by later cosmic influences, such as galactic mergers or dark matter interactions. 



This glimpse into a pristine galaxy in the early universe helps researchers identify the key factors that shaped not only the Milky Way but also other spiral galaxies scattered across the cosmos.



<h2 class="wp-block-heading" id="h-the-power-of-the-james-webb-space-telescope">The power of the James Webb Space Telescope </h2>



As the James Webb Space Telescope prepares to reveal even greater insights, the Firefly Sparkle may mark the beginning of a series of unprecedented discoveries, each deepening our understanding of the universe's distant past.



“This is just the first of many such galaxies JWST will discover, as we are only starting to use these cosmic microscopes,” noted Maruša Bradač from the <a href="https://www.uni-lj.si/en/university" target="_blank" rel="noreferrer noopener">University of Ljubljana</a>. 



“Just like microscopes let us see pollen grains from plants, the incredible resolution of Webb and the magnifying power of gravitational lensing let us see the small pieces inside galaxies.”



The full study was published in the journal <a href="https://www.nature.com/articles/s41586-024-08293-0" target="_blank" rel="noreferrer noopener">Nature</a>.



Image Credit: NASA, ESA, CSA, Ralf Crawford (STScI)



Video Credit: NASA's Goddard Space Flight Center



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Young galaxy shows us what the early Milky Way looked like

It is a fascinating fact that a swirl of stars,...

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Today&#8217;s Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> addresses the question of whether using cannabidiol (CBD) puts you at risk of failing a drug test.
Unlike tetrahydrocannabinol (THC), which is the active chemical in marijuana that makes users feel high, CBD is not psychoactive.
However, the chemical structures of CBD and THC are very similar. In addition, CBD is not FDA-approved, so there is no guarantee that the contents listed on the label are accurate.
A 2017 study from the University of Pennsylvania tested more than 80 CBD products and found traces of THC in over 20 percent of them.
&#8212;
By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer
Video Credit: American Chemical Society

How do CBD products affect drug tests?