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

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

Today's Image of the Day from NASA Earth Observatory features a 9.5-mile section of Pangong Lake on the western end of the Tibetan Plateau. The image was captured by a crew member onboard the International Space Station. 



“In this winter scene, a sheet of cracked ice tops part of the lake,” noted <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA</a>. “On the left side, open water appears blue. Shallow water offshore of a delta, formed by a small, winding river, appears green."



"Parallel lines along the coastlines of bays are visible in the high-resolution version of this image. These lines indicate raised beaches, which formed in the past when lake levels were higher.”



NASA pointed out that several roads cut across the landscape, including one with switchbacks that ascends a steep slope. "These roads facilitate tourist travel from both India and China.”&nbsp;



<h2 class="wp-block-heading" id="h-migratory-birds-at-pangong-lake-nbsp">Migratory birds at Pangong Lake&nbsp;</h2>



Pangong Lake and its surroundings are home to numerous bird species, particularly <a href="https://www.earth.com/news/migratory-birds-burn-unexpected-amounts-of-protein/" target="_blank" rel="noreferrer noopener">migratory birds</a>. Visitors can spot various waterfowl and waders that are rarely seen elsewhere.



“During the summer, species such as bar-headed geese and Brahminy ducks attract bird watchers to the lake, which is a major breeding ground for migrating birds,” said NASA.



Pangong Lake is one of the few places in India where the endangered black-necked crane is found during its breeding season. 



Ruddy shelduck and brown-headed <a href="https://www.earth.com/news/gulls-are-shifting-their-habitats-to-urban-areas/" target="_blank" rel="noreferrer noopener">gulls</a> are also frequently spotted around the lake. The ruddy shelduck is known for its striking orange-brown body and creamy white head, while the brown-headed gulls are often seen flying or swimming in the lake.



<h2 class="wp-block-heading" id="h-pangong-lake-nbsp">Pangong Lake&nbsp;</h2>



Pangong Lake is a stunning high-altitude lake situated in the <a href="https://www.earth.com/news/temperatures-are-rising-unexpectedly-fast-on-the-tibetan-plateau/" target="_blank" rel="noreferrer noopener">Himalayas</a>, extending from India to the Tibetan Autonomous Region of China. It is renowned for its mesmerizing beauty and dramatic setting, with the lake lying at an elevation of about 4,350 meters.



One of the most distinctive features of Pangong Lake is its changing colors, ranging from shades of blue to green and even red, influenced by the sky's reflection and the lake's mineral content.



This saline water lake is approximately 134 kilometers long and 5 kilometers wide at its broadest point. Despite its considerable size, Pangong Lake is relatively shallow.&nbsp;



The lake gained additional popularity after being featured in several Indian films - most notably the Bollywood hit "3 Idiots." Its remote location requires a permit for visitors, especially due to its proximity to the Line of Actual Control between India and China.



Despite the geopolitical sensitivities surrounding its location, Pangong Lake remains a favorite among tourists for its unparalleled natural beauty and serene environment.



<h2 class="wp-block-heading" id="h-high-altitude-lakes">High-altitude lakes</h2>



High-altitude lakes are unique bodies of water found at elevations typically above 3,000 meters (about 10,000 feet) in mountain ranges like the <a href="https://www.earth.com/news/himalayan-glaciers-retreating-threat-is-much-worse-than-previously-believed/" target="_blank" rel="noreferrer noopener">Himalayas</a>, Andes, and Rockies. 



These lakes are formed either by glacial activity, where glaciers erode the earth to create depressions that fill with melted snow and rainwater, or when natural dams created by landslides or moraines trap water in valleys.



<h3 class="wp-block-heading" id="h-extreme-environments">Extreme environments</h3>



The conditions at high altitudes make these lakes distinct in several ways. The climate is typically colder and harsher, with significant temperature variations between day and night. 



This extreme environment affects both the physical characteristics of the <a href="https://www.earth.com/news/alarming-study-most-of-the-worlds-largest-lakes-are-quickly-losing-water/" target="_blank" rel="noreferrer noopener">lakes</a> and the types of ecosystems they support. For example, due to lower atmospheric pressure, the boiling point of water is reduced, which can affect the type of life that can survive in these regions.



<h3 class="wp-block-heading" id="h-critical-habitats">Critical habitats</h3>



Biologically, high-altitude lakes often have limited biodiversity because only certain types of plants and animals can tolerate the cold temperatures and lower oxygen levels in the water. 



Despite this, these lakes are crucial habitats for some unique species of fish, birds, and other wildlife. They also serve as important indicators of climate change, as variations in their water levels and temperatures can reflect environmental shifts.



<h3 class="wp-block-heading" id="h-significance-of-high-altitude-lakes">Significance of high-altitude lakes </h3>



Lakes at high altitudes are often clear and pristine, due to the low density of human populations in these areas and minimal industrial activity, making them significant for ecological studies and attractive for tourism. 



However, they are sensitive ecosystems, and increased tourist activity brings challenges like pollution and habitat disruption.



High-altitude lakes are not only beautiful and scientifically significant but also hold cultural importance for local communities, often considered sacred and associated with historical and spiritual significance.



Image Credit: NASA Earth Observatory&nbsp;



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Pangong Lake on the Tibetan Plateau

Today's Image of the Day from the European Space Agency features the star-forming region NGC 604, which is located 2.73 million light-years away from Earth in the Triangulum Galaxy (M33). The image was captured by the James Webb Space Telescope.



By studying regions like NGC 604, astronomers can gain insights into the complex interactions between stars and the interstellar medium, as well as the conditions that lead to the birth of stars. This, in turn, helps in understanding the evolution of <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">galaxies</a> and the universe as a whole.



<h2 class="wp-block-heading" id="h-massive-stars-of-ngc-604">Massive stars of NGC 604</h2>



"Sheltered among NGC 604’s dusty envelopes of gas are more than 200 of the hottest, most massive kinds of stars, all in the early stages of their lives," said <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



"These types of stars are known as B-types and O-types, the latter of which can be more than 100 times the mass of our own Sun. It’s quite rare to find this concentration of them in the nearby universe. In fact, there’s no similar region within our own Milky Way galaxy."



According to ESA, this concentration of massive stars, combined with its relatively close distance, means that NGC 604 gives astronomers an opportunity to study these objects at a fascinating time early in their life.



<h2 class="wp-block-heading" id="h-gigantic-region-of-ionized-hydrogen">Gigantic region of ionized hydrogen</h2>



NGC 604 is one of the largest known regions of ionized hydrogen, also known as an H II region. This nebula is significantly larger than the Orion Nebula, which is one of the most well-known H II regions in our own <a href="https://www.earth.com/news/large-amount-of-dark-matter-may-be-missing-from-the-milky-way/" target="_blank" rel="noreferrer noopener">Milky Way galaxy</a>.&nbsp;



NGC 604 spans about 1,500 light-years across, making it one of the largest H II regions in the Local Group of galaxies. This group includes the Milky Way, the Andromeda Galaxy, and about 54 other smaller galaxies.&nbsp;



<h2 class="wp-block-heading" id="h-ngc-604-starburst-phenomenon">NGC 604 starburst phenomenon </h2>



Within NGC 604, there are hundreds of young, hot, massive <a href="https://www.earth.com/news/stars-at-the-edge-of-our-milky-way-galaxy-travel-more-slowly/" target="_blank" rel="noreferrer noopener">stars</a>. These stars have ionized the surrounding gas, causing it to glow and creating the nebula. The region is a prime example of a starburst phenomenon, where stars form at a much higher rate than in typical galactic conditions.



“The bright orange streaks in this image signify the presence of carbon-based molecules known as polycyclic aromatic hydrocarbons, or PAHs," explained ESA.



"As you travel further from the immediate cavities of dust where the star is forming, the deeper red signifies molecular hydrogen. This cooler gas is a prime environment for star formation. Ionized hydrogen from ultraviolet radiation appears as a white and blue ghostly glow."



<h2 class="wp-block-heading" id="h-more-about-star-formation">More about star formation </h2>



Star formation is crucial for the evolution of galaxies and the synthesis of heavy elements. In the cores of stars, elements heavier than helium are created.



The elements are spread throughout the <a href="https://www.earth.com/news/ancient-stars-shakti-shiva-shaped-milky-way-galaxy/" target="_blank" rel="noreferrer noopener">galaxy</a> when stars reach the end of their lives and expel their material - either gently through winds or violently via supernova explosions. This enriching process allows for the formation of new stars and planets, and ultimately, the potential for life.



<h3 class="wp-block-heading">Cloud collapse</h3>



The process begins when part of a molecular cloud becomes unstable and starts to collapse under its own gravity. This can be triggered by events like shock waves from nearby <a href="https://www.earth.com/news/supernova-explosions-could-damage-distant-planets/" target="_blank" rel="noreferrer noopener">supernovae</a>, galactic collisions, or the influence of other massive stars.



<h3 class="wp-block-heading">Formation of a protostar</h3>



As the cloud collapses, it fragments into smaller clumps. Each clump will eventually form one or more stars. 



The material within these clumps continues to fall inward, heating up as it does so, eventually forming a warm core called a protostar. At this stage, the protostar is not yet hot enough for nuclear fusion (the process that powers stars) to occur.



<h3 class="wp-block-heading">Accretion disk</h3>



Around the protostar, material from the surrounding cloud continues to fall inward, forming a rotating disk. This material slowly accretes onto the protostar, increasing its mass.



<h3 class="wp-block-heading">Nuclear fusion begins</h3>



Once the core of the protostar reaches a high enough temperature and pressure, hydrogen atoms begin to fuse into helium, releasing energy in the process. This marks the transition from a protostar to a main sequence star, like our sun.



<h3 class="wp-block-heading">Main sequence and beyond</h3>



The star will spend the majority of its life in the main sequence stage, where it balances the gravitational forces trying to collapse it and the outward pressure from nuclear fusion. 



Eventually, the star will exhaust its hydrogen fuel. Its subsequent evolution will depend on its initial mass, leading to various end stages such as red giants, supernovae, neutron stars, or black holes.



Image Credit: NASA/ESA/CSA James Webb Space Telescope



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Young, massive stars in the Triangulum Galaxy

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

Today's Image of the Day from NASA Earth Observatory features the Fedchenko Glacier in the Pamir Mountains of Tajikistan. It is one of the world's longest glaciers outside of the polar regions.&nbsp;



“An astronaut aboard the International Space Station took this photo of glaciers in the high-elevation valleys of the Pamir Mountains of Central Asia. The upper portion of Fedchenko Glacier crosses the center of the scene.”



NASA noted that most of the larger glaciers in the image show a prominent pattern of light- and dark-brown parallel lines.&nbsp;



“The darker ‘streamlines,’ known as medial moraines, give a sense of the direction of flow of the ice down the valleys. These are concentrations of debris that has been eroded by the glacier from the adjacent mountainsides or a rocky outcrop,” said NASA.



<h2 class="wp-block-heading" id="h-fedchenko-a-high-altitude-glacier">Fedchenko: A high-altitude glacier</h2>



Fedchenko Glacier stretches for approximately 48 miles and covers an area of around 270 square miles. This massive glacier is a critical source of <a href="https://www.earth.com/news/satellites-reveal-a-sudden-drop-in-global-freshwater-levels/" target="_blank" rel="noreferrer noopener">freshwater</a>, feeding several rivers and influencing the region's hydrology.



Fedchenko Glacier lies at high altitudes, with its origins in the high peaks of the Pamirs, where snow accumulates heavily. Despite being situated in a relatively arid region, the glacier's significant size and volume are maintained by substantial snowfall.&nbsp;



Named after Alexei Pavlovich Fedchenko, a Russian explorer and naturalist, the glacier was first surveyed in 1928 during Soviet-era expeditions. It plays a crucial role in climate studies, as changes in its length and mass provide insights into the effects of global warming in Central Asia.&nbsp;



The glacier is also part of a spectacular and remote landscape, surrounded by towering <a href="https://www.earth.com/news/early-humans-preferred-the-mountains-and-it-changed-our-evolution/" target="_blank" rel="noreferrer noopener">mountains</a> and rugged terrain, making it a key feature of the Pamirs' natural beauty.&nbsp;



<h2 class="wp-block-heading" id="h-threats-to-glaciers-worldwide">Threats to glaciers worldwide</h2>



Like many glaciers worldwide, Fedchenko faces the threat of retreat due to <a href="https://www.earth.com/news/peru-has-lost-over-half-of-its-glaciers-in-six-decades/" target="_blank" rel="noreferrer noopener">global warming</a>, raising concerns about water availability and ecosystem changes in the region.



Rising global temperatures caused by greenhouse gas emissions are the primary driver of glacier melting. Warmer temperatures not only melt glacier surfaces but also increase the flow of meltwater beneath them, accelerating their disintegration.



<h3 class="wp-block-heading" id="h-human-activities-and-pollution-nbsp">Human activities and pollution&nbsp;</h3>



Deforestation and urbanization exacerbate these effects by reducing reflective snow cover and increasing heat absorption in nearby areas.&nbsp;



Airborne pollutants like soot and black carbon darken glacier surfaces, reducing their ability to reflect sunlight and speeding up the rate of melting. 



Industrial activities and tourism in glacier regions add physical stress and pollution, further degrading these fragile ecosystems.



<h3 class="wp-block-heading" id="h-water-supplies">Water supplies</h3>



The loss of glaciers has far-reaching consequences. It disrupts freshwater supplies for millions of people who depend on glacial runoff for drinking water, agriculture, and hydropower.&nbsp;



<h3 class="wp-block-heading" id="h-rising-sea-levels">Rising sea levels</h3>



<a href="https://www.earth.com/news/melting-glaciers-unleash-invasive-species-into-unexpected-areas/" target="_blank" rel="noreferrer noopener">Melting glaciers</a> contribute to rising sea levels, threatening coastal communities and ecosystems worldwide. Additionally, the loss of glaciers impacts biodiversity, as many species rely on cold, glacial habitats for survival.



<h3 class="wp-block-heading" id="h-protecting-glaciers">Protecting glaciers</h3>



Efforts to mitigate these threats focus on reducing <a href="https://www.earth.com/news/melting-glaciers-are-hidden-sources-of-greenhouse-gases/" target="_blank" rel="noreferrer noopener">greenhouse gas</a> emissions, protecting glacier regions from industrial exploitation, and promoting sustainable tourism practices.&nbsp;



However, without urgent action, the continued decline of glaciers will have profound implications for the planet's climate, water systems, and ecosystems.



<h2 class="wp-block-heading" id="h-the-pamir-mountains-nbsp">The Pamir Mountains&nbsp;</h2>



The Pamir Mountains, often called the "Roof of the World," are a vast and rugged mountain range located in Central Asia.&nbsp;



They span across Tajikistan, Afghanistan, China, and Kyrgyzstan, forming a vital part of the junction where the Himalayas, the Tian Shan, the Karakoram, the Kunlun, and the Hindu Kush converge.&nbsp;



With peaks soaring over 7,000 meters, including Ismoil Somoni Peak, the range is home to some of the highest altitudes on Earth.



The Pamir Mountains have been central to trade and cultural exchange for centuries, serving as a critical segment of the ancient Silk Road.&nbsp;



Today, the mountains are a popular destination for trekkers and explorers drawn by their breathtaking beauty and challenging terrain.



The Pamirs are not only a natural wonder but also a biological treasure trove, supporting unique wildlife that is adapted to extreme altitudes.&nbsp;



Culturally, the mountains are home to diverse communities, each with its unique traditions and ways of life, shaped by the harsh but majestic environment.



Image Credit: NASA Earth Observatory



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Fedchenko Glacier in the Pamir Mountains

Today's Image of the Day from the European Space Agency features the spiral galaxy NGC 5643, which is located roughly 40 million light-years away in the constellation Lupus.&nbsp;



NGC 5643 belongs to the Hubble classification SBc, indicating that it is a barred spiral galaxy with loosely wound arms.&nbsp;



Its orientation, nearly face-on to Earth, provides astronomers with an exceptional view of its detailed spiral structure and central bar.



<h2 class="wp-block-heading" id="h-ngc-5643-a-grand-design-spiral-nbsp">NGC 5643: A grand design spiral&nbsp;</h2>



“NGC 5643 is what’s known as a grand design spiral, referring to how the galaxy’s two large, winding spiral arms are clear to see,” noted <a href="https://www.esa.int/ESA_Multimedia/Images">ESA</a>. “The spiral arms are defined by bright blue stars, lacy reddish-brown dust clouds and pink star-forming regions.”



“As fascinating as the galaxy appears at visible wavelengths, some of NGC 5643’s most interesting features are invisible to the human eye.”&nbsp;



<h2 class="wp-block-heading" id="h-intense-activity-in-ngc-5643">Intense activity in NGC 5643</h2>



This galaxy is notable for its Seyfert 2 nucleus, a type of active galactic nucleus (AGN). The intense activity in its core is powered by a supermassive <a href="https://www.earth.com/news/awakening-of-a-black-hole-witnessed-for-the-first-time/">black hole</a> that accretes surrounding material, emitting energy across a wide range of wavelengths.&nbsp;



“When a supermassive black hole ensnares gas from its surroundings, the gas collects in a disc that heats up to hundreds of thousands of degrees. The superheated gas shines brightly across the electromagnetic spectrum, but especially at X-ray wavelengths,” said ESA.



Observations have revealed jets and outflows of material emanating from the nucleus, likely driven by the black hole’s activity.&nbsp;



NGC 5643’s AGN has been studied extensively for its role in galactic evolution, particularly in how its energetic processes interact with the galaxy’s interstellar medium.



<h2 class="wp-block-heading" id="h-the-mystery-of-ngc-5643-x-1">The mystery of NGC 5643 X-1</h2>



However, ESA pointed out that NGC 5643’s active galactic nucleus isn’t the brightest source of X-rays in the galaxy.&nbsp;



“Researchers using ESA’s XMM-Newton discovered an even brighter X-ray-emitting object, called NGC 5643 X-1, on the galaxy’s outskirts. What could be a more powerful source of X-rays than a <a href="https://www.earth.com/news/how-do-black-holes-become-supermassive/">supermassive black hole</a>?”&nbsp;



“Surprisingly, the answer appears to be a much smaller black hole! While the exact identity of NGC 5643 X-1 is not yet known, evidence points to a black hole that is about 30 times more massive than the Sun.”&nbsp;



“Locked in an orbital dance with a companion star, the black hole ensnares gas from its stellar companion, creating a superheated disc that outshines the galactic center,” said ESA.



<h2 class="wp-block-heading" id="h-star-formation-in-ngc-5643">Star formation in NGC 5643</h2>



NGC 5643 also exhibits prominent regions of <a href="https://www.earth.com/news/six-rogue-worlds-discovered-inside-a-young-star-forming-nebula/">star formation</a> within its spiral arms. These areas are rich in gas and dust - the raw materials for birthing new stars - and glow brightly in ultraviolet and infrared light.&nbsp;



Observations from the Hubble Space Telescope and the Very Large Telescope (VLT) have helped uncover the complex interplay between star formation and the galaxy's central activity.



<h2 class="wp-block-heading" id="h-extended-ionized-gas-regions-nbsp">Extended ionized gas regions&nbsp;</h2>



A defining feature of NGC 5643 is the presence of its extended ionized gas regions, which are shaped by the galaxy's AGN activity and star-forming regions.&nbsp;



These structures have been mapped through optical spectroscopy, revealing intricate patterns that help astronomers understand the physical conditions of the gas, such as density, temperature, and composition.



The galaxy also has a dust lane that crosses its nucleus, partially obscuring direct observations of the central region in visible light.&nbsp;



Overall, NGC 5643 offers a fascinating glimpse into the dynamics of barred <a href="https://www.earth.com/news/the-mesmerizing-beauty-of-spiral-galaxies/">spiral galaxies</a> with active nuclei, serving as a valuable resource for studying the interactions between supermassive black holes, star formation, and galactic evolution.



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



Lupus is a constellation located in the southern sky, its name meaning "wolf" in Latin. It has been known since antiquity and was cataloged by the Greek astronomer Ptolemy.&nbsp;



Once part of the larger constellation Centaurus, Lupus was later recognized as a distinct constellation. It is relatively faint but holds historical significance in mythology, often associated with a sacrificial wolf in ancient stories.



Lupus is bordered by other constellations like Scorpius, Centaurus, and Libra. Its stars do not form a particularly striking pattern, but it contains a variety of interesting astronomical features. Among them are numerous double stars, globular clusters, and other deep-sky objects, visible through telescopes.&nbsp;



For observers in the Southern Hemisphere, Lupus is best seen in the winter and spring months, while it appears closer to the horizon for those in northern latitudes.



This constellation also lies along the <a href="https://www.earth.com/news/stars-at-the-edge-of-our-milky-way-galaxy-travel-more-slowly/">Milky Way</a>, offering a rich field of stars and nebulae for stargazers. Despite its modest brightness, Lupus holds a special place in the science of astronomy.



Image Credit: NASA/ESA Hubble Space Telescope



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NGC 5643: Secrets of a spiraling galactic powerhouse

Today's Image of the Day from NASA Earth Observatory features an astronaut view of Mount Nemrut, a volcano located in eastern Turkey near Lake Van.



Mount Nemrut is notable for its immense caldera, which was formed through a series of <a href="https://www.earth.com/news/volcanic-eruptions-play-an-overlooked-role-in-earths-climate/" target="_blank" rel="noreferrer noopener">eruptions</a>. The caldera, one of the largest in the world, now contains several lakes such as Lake Nemrut.&nbsp;



"The eastern half of the caldera is partially filled by solidified lava flows from past eruptions. Snow cover present at the time of this photo accentuates pressure ridges that formed as the lava was flowing and cooling," noted <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA</a>.



"These pressure ridges vary in size, thickness, and orientation due to the varying viscosity and flow direction of the lavas during eruptions."



<h2 class="wp-block-heading" id="h-formation-of-lake-nemrut">Formation of Lake Nemrut</h2>



"Lake Nemrut (Nemrut Gölü) occupies the western half of the caldera, creating a rough crescent shape that partially submerges the old lava flows," said NASA.



"This freshwater lake, reaching up to 176 meters deep, is accompanied by a smaller lake at the upper-center of the caldera."



The lake was formed after the collapse of the Nemrut volcano's summit. This collapse created a massive crater, which gradually filled with water over time, forming the <a href="https://www.earth.com/news/alarming-study-most-of-the-worlds-largest-lakes-are-quickly-losing-water/" target="_blank" rel="noreferrer noopener">lake</a>.



<h2 class="wp-block-heading" id="h-unesco-world-heritage-site">UNESCO World Heritage Site </h2>



Mount Nemrut and its surroundings are part of a protected UNESCO World Heritage Site due to their ecological and geological significance.



The site is home to diverse wildlife, including various bird species that use the lake as a stopover during migration. The caldera also contains smaller lakes and wetlands, adding to the area's biodiversity.



Lake Nemrut is a popular destination for tourists, hikers, and nature enthusiasts, offering stunning views of the volcanic landscape.



Despite its popularity, the lake remains relatively remote and unspoiled, contributing to its appeal as a natural wonder.



<h2 class="wp-block-heading" id="h-mount-nemrut-has-shaped-the-landscape">Mount Nemrut has shaped the landscape</h2>



Geologically, Mount Nemrut is interesting because its <a href="https://www.earth.com/news/new-research-enhances-predictions-on-volcanic-eruptions/" target="_blank" rel="noreferrer noopener">eruptions</a> have played a key role in shaping the local landscape. 



Its last major eruption occurred around 1441 AD, which indicates that it's not currently active but is considered dormant.



The area around Nemrut is known for its geothermal activity, including hot springs and fumaroles, suggesting that there is still significant heat beneath the surface.



Over thousands of years, various civilizations have inhabited the region around Nemrut, leaving behind a wealth of archaeological sites.



<h2 class="wp-block-heading" id="h-tribute-to-a-king">Tribute to a king</h2>



The summit of Mount Nemrut is dominated by a vast funerary mound constructed by King Antiochus I Theos, who ruled the Kingdom of Commagene in the 1st century BCE. 



The site was intended to serve as his tomb sanctuary and a place to commemorate the king's vision of divine kingship and unity between Eastern and Western cultures.



The mound, made of loose crushed stones, measures about 50 meters (164 feet) in height and spans a diameter of 150 meters (492 feet), creating an imposing feature visible from afar.



Surrounding the mound are terraces on the eastern, western, and northern sides, each adorned with colossal statues and reliefs. The statues, ranging in height from 8 to 10 meters (26 to 33 feet), represent various deities, including Zeus, Apollo, Hercules, and the goddess Tyche, alongside King Antiochus himself. 



The heads of the statues, many of which have toppled over due to <a href="https://www.earth.com/news/new-map-shows-75-percent-of-the-u-s-at-risk-of-damaging-earthquakes/" target="_blank" rel="noreferrer noopener">earthquakes</a> and erosion, lie scattered around the site, creating an iconic and enigmatic scene.



<h2 class="wp-block-heading" id="h-spiritual-and-religious-practices">Spiritual and religious practices</h2>



In addition to the statues, inscriptions at Mount Nemrut provide valuable historical information about the kingdom, the king's lineage, and the religious practices of the time.



The site is not only a marvel of ancient engineering but also a spiritual and astronomical center. Scholars believe the terraces were aligned with celestial events, serving as an observatory for solstices and equinoxes.



In addition to its natural and historical significance, the Nemrut volcano has been the subject of scientific study, as researchers aim to understand more about <a href="https://www.earth.com/news/volcanic-eruptions-play-an-overlooked-role-in-earths-climate/" target="_blank" rel="noreferrer noopener">volcanic activity</a> in the region, the history of its eruptions, and the potential risks it may pose in the future.



Image Credit: NASA Earth Observatory



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Mount Nemrut: Ancient mysteries and natural marvels 

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features a dam on the Blue Nile that is set to become Africa’s largest hydroelectric dam upon its completion in 2023.



In Ethiopia, only about half of the citizens have access to electricity. To address this issue, the government launched the dam project in 2011.



"With three spillways and 13 turbines, the concrete structure will rise 475 feet and create a reservoir that will cover 724 square miles of land, an area about the size of Houston, Texas. Called the Grand Ethiopian Renaissance Dam (GERD), it should more than double Ethiopia’s output of electricity," reports NASA.



Beyond generating electricity, GERD is expected to reduce destructive seasonal floods in Sudan, provide a more reliable supply of water for irrigation, and extend the lifespan of other dams by trapping sediment.



At the same time, however, the dam could potentially impact millions of people who live and farm downstream in Egypt and parts of Sudan.



"After 10 years of construction, GERD is almost complete. In 2020, water managers started filling the reservoir, a process that could take from a few years to a decade depending on weather conditions and how much of the Blue Nile’s flow the dam managers hold back," says NASA.



"Ethiopia has an incentive to fill the reservoir quickly to start generating power and start paying for the $5 billion dollar project. However, rapid filling could significantly reduce the water downstream since the Blue Nile provides 60 percent of the water that flows into the Nile."



Essam Heggy is a NASA Jet Propulsion Laboratory scientist who recently co-authored a study analyzing the potential hydrological and economic consequences of filling the dam at various rates.



“While the dam will certainly have positive effects in regards to flood control and hydroelectric power, there are important unanswered questions about how quickly the reservoir should be filled, and how it will be managed long term,” said Heggy.



“Filling the reservoir too quickly - in less than seven years - could lead to measurable water shortages downstream that impact food production, especially if the initial filling occurs under drought conditions."



Image Credit: NASA Earth Observatory&nbsp;



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



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The Grand Ethiopian Renaissance Dam on the Blue Nile

A new study provides compelling evidence that the Chicxulub meteorite impact, rather than massive volcanic activity, was the principal driver behind the extinction of the dinosaurs 66 million years ago.&nbsp;



Climate scientists from <a href="https://www.uu.nl/en" target="_blank" rel="noreferrer noopener">Utrecht University</a> and the <a href="https://www.manchester.ac.uk/" target="_blank" rel="noreferrer noopener">University of Manchester</a> have found that the climatic disturbances caused by colossal volcanic eruptions in India had largely subsided thousands of years before the meteorite struck, leaving the asteroid impact as the ultimate reason for the dinosaurs’ demise.&nbsp;



The findings, published in <a href="http://dx.doi.org/10.1126/sciadv.ado5478">Science Advances</a>, help resolve a decades-long scientific debate.



“These <a href="https://www.earth.com/news/violent-volcanic-eruptions-likely-caused-dinosaur-extinction/" target="_blank" rel="noreferrer noopener">volcanic eruptions</a> and associated CO₂ and sulphur release would have had drastic consequences for life on Earth,” said Lauren O’Connor, a researcher at Utrecht University. “But these events happened millennia before the meteorite impact and probably played only a small part in the extinction of dinosaurs.”



<h2 class="wp-block-heading" id="h-controversy-over-dinosaur-extinction-nbsp">Controversy over dinosaur extinction&nbsp;</h2>



For many years, researchers have debated whether the catastrophic <a href="https://www.earth.com/news/nadir-crater-second-massive-asteroid-impact-discovered-dinosaur-extinction/" target="_blank" rel="noreferrer noopener">asteroid</a> impact near the present-day Gulf of Mexico or the extensive volcanic eruptions of the Deccan Traps in India led to the mass extinction that ended the Cretaceous Period.&nbsp;



Both events significantly impacted Earth’s climate and ecosystems. The asteroid impact unleashed a chain of disasters including massive wildfires, tsunamis, earthquakes, and a lingering “impact winter” that darkened the skies and devastated the global food chain.



Meanwhile, the Deccan Traps eruptions, occurring both before and after the asteroid strike, released huge volumes of CO₂, dust, and sulphur into the atmosphere.&nbsp;



These emissions could have induced substantial warming or cooling, depending on their composition and duration. Determining which event bore the greatest responsibility for the dinosaurs’ extinction has long proved challenging due to their overlapping timelines and complex climatic effects.



<h2 class="wp-block-heading" id="h-clues-in-ancient-peats">Clues in ancient peats</h2>



To break this impasse, the research team turned to an innovative method: examining ancient peats in the United States for molecular fossils that record past temperatures.&nbsp;



Certain bacteria produce characteristic membrane-spanning molecules that vary in structure with ambient temperature.&nbsp;



By analyzing these molecular traces in sediments from the time leading up to the dinosaur extinction, the researchers reconstructed detailed timelines of Earth’s climate.



<h2 class="wp-block-heading" id="h-temperature-timeline-leading-to-dinosaur-extinction-nbsp">Temperature timeline leading to dinosaur extinction&nbsp;</h2>



The analysis uncovered a distinct sequence of events. Approximately 30,000 years before the asteroid impact, a major phase of Deccan Traps volcanism triggered significant climate change, cooling the Earth’s surface by at least 5° Celsius.&nbsp;



This cooling was most likely caused by volcanic sulphur emissions, which blocked incoming sunlight.&nbsp;



However, the record shows that some 20,000 years before the asteroid struck, global temperatures had already rebounded, returning to levels similar to those before the volcanic eruptions.



“We were able to create a detailed ‘temperature timeline’ for the years leading up to the dinosaur extinction,” O’Connor explained. “By aligning these <a href="https://www.earth.com/news/dinosaurs-may-have-become-warm-blooded-180-million-years-ago/" target="_blank" rel="noreferrer noopener">climate changes</a> with the fossil record, we can better understand the relative timing of these events.”



<h2 class="wp-block-heading" id="h-volcanic-effects-had-faded-before-the-impact">Volcanic effects had faded before the impact</h2>



The revelation that Earth’s climate had stabilized well in advance of the Chicxulub meteorite impact is crucial. Although the Deccan Traps eruptions undoubtedly stressed ecosystems and altered climates, their effects had dissipated long before the asteroid arrived.&nbsp;



With the volcanic disruptions out of the picture during the critical window, the data strongly point to the meteorite collision as the primary catalyst for the extinction event.



This finding helps distinguish between the gradual, prolonged influence of volcanism and the abrupt, globally catastrophic consequences of the asteroid strike.&nbsp;



The volcanoes may have prepared a stage of ecological vulnerability, but they did not deliver the final, fatal blow. By the time the asteroid hit, Earth’s systems had largely recovered from the volcanic perturbations.



<h2 class="wp-block-heading" id="h-the-asteroid-s-fatal-blow">The asteroid’s fatal blow</h2>



With volcanic influences waning thousands of years before the end of the Cretaceous, the Chicxulub meteorite impact emerges more clearly than ever as the decisive factor behind the dinosaurs’ extinction.&nbsp;



Unlike volcanic activity, which occurs over extended periods, the asteroid collision was sudden and brutally efficient, throwing a shroud of debris into the atmosphere, blocking sunlight, and triggering a cascade of environmental calamities.



“By comparison, the impact from the asteroid unleashed a chain of disasters, including wildfires, earthquakes, tsunamis, and an ‘<a href="https://www.earth.com/news/nuclear-winter-dinosaurs-were-likely-killed-by-dust/" target="_blank" rel="noreferrer noopener">impact winter</a>’ that blocked sunlight and devastated ecosystems,” said Rhodri Jerrett of the University of Manchester. “We believe the asteroid ultimately delivered the fatal blow.”



This swift and worldwide onslaught overwhelmed ecosystems, knocking out plant life dependent on sunlight and collapsing food webs that supported large terrestrial animals like dinosaurs.&nbsp;



While some species survived - leading to the rise of mammals and, eventually, humans - the mighty dinosaurs could not endure this sudden catastrophe.



<h2 class="wp-block-heading" id="h-an-accurate-picture-of-earth-s-past">An accurate picture of Earth’s past</h2>



The methods employed in this study highlight the power of molecular paleoclimatology. By examining microscopic bacterial remains embedded in ancient sediments, scientists can now resolve the timing and intensity of climate changes from millions of years ago with remarkable precision.&nbsp;



These advances allow researchers to clarify the interplay between volcanic eruptions, asteroid impacts, and mass extinctions, painting a more accurate picture of Earth’s deep past.



The study’s conclusions provide a clearer understanding of why the dinosaurs disappeared. While volcanic activity did shape the Earth’s environment, it was not the immediate executioner. 



Instead, the researchers confirm that the Chicxulub impact, with its sudden and universal repercussions, was the ultimate cause of the <a href="https://www.earth.com/news/dinosaurs-evolved-feathers-for-much-more-than-just-flying/" target="_blank" rel="noreferrer noopener">dinosaurs</a>’ end.



“These findings help us understand the relative timing of events and confirm that the asteroid was the ultimate driver of the extinction event,” O’Connor said.



Armed with these insights, scientists can continue to refine their understanding of ancient Earth crises, shedding light on how life responds to abrupt environmental shifts - lessons that may prove valuable as our planet faces its own ecological challenges today.



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Dinosaur extinction was not caused by global volcanic eruptions 

A new study provides compelling evidence that the Chicxulub meteorite...

The Anthropic Principle, first proposed by Brandon Carter in 1973, suggests that the universe is “fine-tuned” to support life. Since then, it has sparked heated debate among scientists and philosophers alike.&nbsp;



Some view it as an elegant observation, while others argue it lacks scientific utility. Now, for the first time, researchers have outlined a way to test this assumption experimentally.&nbsp;



In a new paper, physicists Nemanja Kaloper from the <a href="https://www.ucdavis.edu/" target="_blank" rel="noreferrer noopener">University of California, Davis</a>, and Alexander Westphal from <a href="https://www.desy.de/" target="_blank" rel="noreferrer noopener">Deutsches Elektronen-Synchrotron</a> (DESY) present a method to scrutinize the principle through upcoming astronomical observations.



<h2 class="wp-block-heading" id="h-what-is-the-anthropic-principle">What Is the Anthropic Principle?</h2>



The Anthropic Principle (AP) comes in two main forms. The "Weak Anthropic Principle" states that we can only observe conditions in the universe that allow for our existence.&nbsp;



For example, the universe must have the specific properties that permit the formation of stars, planets, and ultimately life because - if it didn’t - we wouldn’t be here to contemplate it.



The "Strong Anthropic Principle" goes further, proposing that the universe’s laws and constants are fine-tuned in a way that life must emerge, implying a deeper or possibly intentional explanation for this apparent design.



The problem, as many scientists argue, is that the AP does not produce clear, testable predictions - something crucial for any scientific hypothesis.&nbsp;



However, Kaloper and Westphal’s new approach changes that. They propose specific conditions that could confirm or disprove the principle using current cosmological models and future observations.



<h2 class="wp-block-heading" id="h-ingredients-for-testing-the-anthropic-principle">Ingredients for testing the Anthropic Principle</h2>



Kaloper and Westphal focus on three key areas of cosmology: cosmic inflation, dark matter, and axions.



<h3 class="wp-block-heading" id="h-cosmic-inflation">Cosmic inflation</h3>



In its earliest moments, the universe underwent a rapid <a href="https://www.earth.com/news/unknown-factors-are-accelerating-the-expansion-of-the-universe/" target="_blank" rel="noreferrer noopener">expansion</a> known as cosmic inflation. In less than a trillionth of a second (10⁻³⁶ seconds), the universe grew from a minuscule size to something macroscopic.&nbsp;



Though we still lack direct evidence, cosmic inflation is a strong theory that explains how galaxies and other structures came to form.&nbsp;



Future experiments, like Japan’s LiteBIRD satellite (set to launch in 2032), aim to confirm this phase through observations of primordial <a href="https://www.earth.com/news/gravitational-waves-dark-matter-big-bang-breakthrough/" target="_blank" rel="noreferrer noopener">gravitational waves</a>.



<h3 class="wp-block-heading" id="h-dark-matter">Dark matter</h3>



Scientists know that about five-sixths of the universe’s matter is <a href="https://www.earth.com/news/existence-of-dark-matter-confirmed-by-new-study/" target="_blank" rel="noreferrer noopener">dark matter</a> - an invisible substance we can’t directly observe.&nbsp;



While its nature remains mysterious, its existence is inferred from gravitational effects on galaxies and other large structures. Future searches could help identify what dark matter actually is.



<h3 class="wp-block-heading" id="h-axions">Axions</h3>



One of the leading candidates for dark matter is the axion - a tiny, lightweight particle that interacts very weakly with ordinary matter. Axions were initially proposed to explain a quantum anomaly but later emerged as a dark matter candidate.&nbsp;



Some theories suggest they were produced in large numbers during cosmic inflation, and upcoming studies of <a href="https://www.earth.com/news/black-hole-jet-crashes-into-an-unidentified-object/" target="_blank" rel="noreferrer noopener">black holes</a> may confirm their existence.



<h2 class="wp-block-heading" id="h-what-the-observations-could-reveal">What the observations could reveal</h2>



Kaloper and Westphal’s proposal combines these three elements into a testable framework. If their predictions align with observations, it could validate the Anthropic Principle - or potentially disprove it.



“It is possible that the LiteBIRD satellite discovers primordial gravity waves close to the current limits, which match high-scale inflation,” Kaloper explained. “Most cosmologists would feel this confirms high-scale inflation.”



At the same time, researchers are studying supermassive black holes to search for signs of ultralight axions. “The axions affect the spin-to-mass ratio of black holes, and this could be observed,” Kaloper added.



Crucially, Kaloper described a third outcome: direct searches for dark matter might reveal that dark matter is not made up of axions. “In which case, we’d think that the Anthropic Principle fails.”



On the flip side, if ultralight axions are confirmed as dark matter, it would strengthen the case for the Anthropic Principle. “I think we’d agree that the Anthropic Principle in fact passed this test; indeed, this might happen,” Kaloper said.



<h2 class="wp-block-heading" id="h-what-if-the-anthropic-principle-fails">What if the Anthropic Principle fails?</h2>



While Kaloper and Westphal’s work opens the door to testing the AP, it also raises the question: what happens if it fails?



“Without changing any of the other premises - universality of gravity, early inflation, and superradiant phenomena - the failure of our simple formulation of anthropics would suggest that different rules govern the initial conditions,” Kaloper explained.



He outlined a few possibilities:



<ul class="wp-block-list">
<li>New dynamics might bias some initial conditions, making them more likely than others.</li>



<li>Some initial conditions might simply be impossible.</li>



<li>The real theory of cosmology might be far more complex than we currently understand.</li>
</ul>



“Alternatively, one could imagine more dramatic scenarios, but at least for now, to me those seem like flights of fancy,” said Kaloper.&nbsp;



<h2 class="wp-block-heading" id="h-a-promising-future-for-cosmology">A promising future for cosmology</h2>



This study marks the first time the Anthropic Principle could be subject to rigorous testing. Over the next few years, data from gravitational wave studies, black hole surveys, and dark matter experiments may confirm - or challenge - its assumptions.



“I find it particularly interesting that both of these options might be experimentally tested in the not-too-distant future. Our specific example is the first case where the Anthropic Principle might actually fail the test, as opposed to simply declaring that it does not apply.”



The search for answers may take time, but with each new discovery, we move closer to unraveling the origins and laws of our <a href="https://www.earth.com/news/missing-law-of-nature-explains-the-evolution-of-everything-that-exists-in-the-universe/" target="_blank" rel="noreferrer noopener">universe</a> - and our place within it.



The research is published in the <a href="https://iopscience.iop.org/article/10.1088/1475-7516/2024/12/017" target="_blank" rel="noreferrer noopener">Journal of Cosmology and Astroparticle Physics</a>.



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Anthropic Principle: We live in a universe fine-tuned to support life

The Anthropic Principle, first proposed by Brandon Carter in 1973,...

When we talk about the prevention and management of cancer, we don’t usually think that diet changes would be very helpful. But a recent study begs to differ.



The research suggests that dietary changes may play a role in slowing tumor growth in cancer patients. 



Experts at UCLA focused on men with early-stage prostate cancer and observed notable differences in tumor progression based on dietary habits.



The findings could pave the way for lifestyle changes to complement cancer treatment strategies.



<h2 class="wp-block-heading" id="h-diet-and-cancer-progression">Diet and cancer progression</h2>



The year-long study included 100 men with early-stage prostate <a href="https://www.earth.com/news/ketogenic-diet-may-help-the-body-kill-cancer-cells/" target="_blank" rel="noreferrer noopener">cancer</a>. Researchers divided participants into two groups. 



One group followed a diet low in omega-6 fats (found in seed oils) and high in omega-3 fats (found in fish like salmon). The other group continued their usual Western diet.



By the end of the study, participants who adjusted their diets showed a 15% decrease in tumor aggression markers. 



Meanwhile, the group on a standard Western diet saw a 24% increase in these markers. These results suggest that dietary fats may influence cancer progression.



"Our findings suggest that something as simple as adjusting your diet could potentially slow cancer growth and extend the time before more aggressive interventions are needed," noted Dr. William Aronson, a professor of urology at <a href="https://www.ucla.edu" target="_blank" rel="noreferrer noopener">UCLA</a> and the study’s lead researcher.



<h2 class="wp-block-heading" id="h-seed-oils-of-the-western-diet">Seed oils of the Western diet </h2>



Seed oils, such as canola, corn, and cottonseed oils, are staples of the Western diet. They are rich in omega-6 fats, which have been linked to increased inflammation in some studies. 



Inflammation, in turn, can fuel cancer growth by damaging tissues and weakening the body’s ability to <a href="https://www.earth.com/news/ai-is-the-next-frontier-in-cancer-treatment/" target="_blank" rel="noreferrer noopener">fight tumors</a>.



On the other hand, omega-3 fats, found in fish, nuts, and flaxseeds, are known for their anti-inflammatory properties. 



They may support the immune system and reduce tumor growth risks. Previous animal studies also support the idea that lowering omega-6 intake while increasing omega-3 intake can slow cancer progression.



<h2 class="wp-block-heading" id="h-non-invasive-interventions">Non-invasive interventions</h2>



Prostate cancer is the second-leading cause of <a href="https://www.earth.com/news/banana-peel-flour-adds-cancer-fighting-nutrients-to-snacks/" target="_blank" rel="noreferrer noopener">cancer</a>-related deaths in American men. An estimated&nbsp;299,010 cases&nbsp;will be diagnosed in 2024, with approximately&nbsp;201,000 patients&nbsp;in the early stages of the disease. 



Many patients opt for active monitoring rather than immediate surgery, radiation, or chemotherapy.



For these patients, lifestyle changes, including diet modifications, could delay the need for aggressive treatments. The study’s results highlight a potential non-invasive option to manage early-stage prostate cancer. 



"This significant difference suggests that the dietary changes may help slow cancer growth, potentially delaying or even preventing the need for more aggressive treatments," said Dr. Aronson.



<h2 class="wp-block-heading" id="h-seed-oils-and-cancer-risks">Seed oils and cancer risks</h2>



Despite these findings, leading medical bodies, including the American Heart Association, maintain that seed oils are safe and not linked to <a href="https://www.earth.com/news/which-dietary-changes-are-best-for-cancer-prevention/" target="_blank" rel="noreferrer noopener">cancer</a>. 



However, public opinion on seed oils has become increasingly divided. Critics, including public figures like Robert F. Kennedy Jr., claim seed oils contribute to the obesity epidemic and related health concerns.



Adding to the controversy, a recent study from the University of South Florida linked seed oils to rising cases of colon cancer in young adults. 



The researchers suggested that the fats in seed oils might promote inflammation, thus creating an environment conducive to tumor growth.



<h2 class="wp-block-heading" id="h-balanced-approach-to-diet">Balanced approach to diet</h2>



The UCLA researchers emphasized that, while their findings are promising, more research is needed to confirm the connection between diet and cancer progression. 



They also stressed the importance of maintaining a balanced diet rather than eliminating specific foods.



According to Dr. Aronson, the study&nbsp;is an important step toward understanding how diet can potentially influence prostate cancer outcomes.



Future studies could offer more targeted dietary recommendations for the thousands of men diagnosed with prostate cancer each year. 



A deeper understanding of how dietary fats influence cancer might help to reduce reliance on invasive and costly treatments like surgery or chemotherapy.



<h2 class="wp-block-heading" id="h-can-diet-be-a-tool-against-cancer">Can diet be a tool against cancer?</h2>



The evidence suggests that cutting back on omega-6 fats and incorporating omega-3-rich foods could slow the progression of early-stage prostate <a href="https://www.earth.com/news/molecular-jackhammers-a-breakthrough-in-cancer-treatment/" target="_blank" rel="noreferrer noopener">cancer</a>. 



However, experts agree that there is a need for further research to validate these findings and provide actionable dietary guidelines.



For now, adopting a balanced diet rich in anti-inflammatory foods like fish, nuts, and seeds may offer additional benefits for <a href="https://www.earth.com/news/caterpillar-fungus-slows-down-growth-of-cancer-cells/" target="_blank" rel="noreferrer noopener">cancer</a> patients. While diet alone may not cure cancer, it could play a significant role in improving outcomes and quality of life.



The study is published in the journal <a href="https://ascopubs.org/doi/abs/10.1200/JCO.24.00608">Clinical Oncology</a>.



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Many cooking oils in your diet are now being linked to cancer

When we talk about the prevention and management of cancer,...

The number of humans inhabiting the Earth has steadily increased since Homo sapiens began to assert their dominance over the planet. Now, however, the global population growth trend is on the verge of becoming unsustainable.



Historians report that, by the 10th century, the global headcount hovered around a few hundred million. 



Later, the Industrial Revolution and better living conditions pushed our numbers ever upward. We soared past 1 billion by 1900 and over 6 billion by 2000.



Not long ago, in late 2022, we crossed the 8 billion mark. Now, new studies suggest this steady climb may soon slow down and, eventually, our population might grow smaller, not bigger.



<h2 class="wp-block-heading" id="h-global-population-trend">Global population trend</h2>



Some recent findings, published in <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(24)00550-6/fulltext" target="_blank" rel="noreferrer noopener">The Lancet</a>, and relying on data from the <a href="https://www.healthdata.org/" target="_blank" rel="noreferrer noopener">Institute for Health Metrics</a> and Evaluation at the University of Washington, point to a different future.



According to these projections, by 2050 about 155 out of 204 countries will not have enough births to ensure a stable global population count. And by 2100, almost all of them, around 198 out of 204, will be in the same boat.



This has led researchers to believe that deaths will soon outnumber births in many places, which will shift long-held patterns.



“This is our most comprehensive analysis to date,” said <a href="https://www.healthdata.org/about/people/stein-emil-vollset" target="_blank" rel="noreferrer noopener">Dr. Stein Emil Vollset</a>, a professor at the Institute for Health Metrics and Evaluation (IHME) at the <a href="https://www.washington.edu/" target="_blank" rel="noreferrer noopener">University of Washington</a>.



<h2 class="wp-block-heading" id="h-why-does-global-population-matter">Why does global population matter?</h2>



The idea that the <a href="https://www.earth.com/news/geologists-found-the-worlds-largest-iron-ore-deposit/">world</a> might become a less crowded place raises a few eyebrows, but also a few hopes. Some have argued that thinning numbers might help reduce the strain on certain resources.



There is talk of a demographic dividend, a scenario where fewer dependents and more working-age adults boost economies.



Yet, in many places the total fertility rate has dropped below replacement levels and stays there, without any predicted bounce back. The old assumption that decreasing fertility would fix itself has not been supported by recent data.



When fewer <a href="https://www.earth.com/news/babies-are-born-with-the-ability-to-recognize-the-beat-in-music/" target="_blank" rel="noreferrer noopener">babies are born</a>, the workforce thins out in a matter of decades. 



Economic systems depend on a steady stream of workers, consumers, and taxpayers. If countries produce fewer citizens, they may struggle to maintain productivity and keep growth on track.



Economists worry that, as population structures skew towards older groups, tax bases might shrink, and this could make it harder to pay for services that keep society running smoothly.



Some analyses of demographic shifts have shown that countries with aging populations feel strain on their labor supply, which may lead to shifts in markets and wage structures.



<h2 class="wp-block-heading" id="h-caring-for-older-generations">Caring for older generations</h2>



A decreasing global population also means a rising proportion of <a href="https://www.earth.com/news/public-perception-of-old-age-has-shifted-to-later-in-life/" target="_blank" rel="noreferrer noopener">older people</a>.



While living longer can be a sign of progress, it also brings its own problems. More older adults need care for chronic conditions, assisted living, and medical services that handle age-related diseases.



Health care systems might need to reinvent themselves to deal with shortages in skilled medical staff and the growing demand for long-term support. 



Without enough younger workers, caregiving roles may be harder to fill, putting pressure on families and communities.



Studies have outlined the growing costs of eldercare as populations age, warning that countries must adapt soon or face long waiting times and inadequate care.



<h2 class="wp-block-heading" id="h-global-population-and-the-environment">Global population and the environment</h2>



Fewer humans might sound like a perfect recipe for less stress on forests, oceans, farmland, and energy supplies. 



Reduced consumption could mean less pollution, fewer greenhouse gas emissions, and cleaner water in some areas.



But changing population distribution patterns could complicate resource management. If certain places empty out and others remain crowded, it might be tricky to balance who gets what.



Environmental changes also depend on how people live, not just how many there are. Some research suggests that even with fewer people, lifestyle choices still matter for keeping ecosystems healthy and <a href="https://www.earth.com/news/effective-conservation-efforts-key-to-saving-biodiversity/" target="_blank" rel="noreferrer noopener">maintaining biodiversity</a>.



<h2 class="wp-block-heading" id="h-rewriting-global-influence">Rewriting global influence</h2>



As nations experience shifts in their population counts, political and economic influence could get shuffled. 



Countries that once dominated trade, technology, or culture might find themselves overshadowed by others that manage to keep younger <a href="https://www.earth.com/news/global-population-will-peak-at-10-3-billion-by-2085/" target="_blank" rel="noreferrer noopener">populations engaged</a>.



Alliances that seemed stable might look different when a partner’s population contracts. This could ripple through security agreements, resource negotiations, and geopolitical strategies. 



Realigning priorities might become a necessity as demographic trends change who holds the cards on the world stage.



<h2 class="wp-block-heading" id="h-rethinking-family-decisions">Rethinking family decisions</h2>



Falling fertility rates are often linked to changing social expectations, improved women’s rights, and better access to education. 



There is a growing concern that some leaders might try to push quick fixes that harm personal freedoms.



Policies that put pressure on women to have more children present significant risks, threatening reproductive and sexual rights. 



In some places, such measures could limit access to necessary services or reduce the freedom to choose whether and when to become parents.



Historical analyses warn that forcing fertility through policy often backfires, causing social tension and distrust.



<h2 class="wp-block-heading" id="h-a-new-normal">A new normal</h2>



The notion of an emptier planet comes with no simple answers. A world with fewer new births may <a href="https://www.earth.com/news/anthropocene-when-did-humans-begin-changing-the-earth/" target="_blank" rel="noreferrer noopener">reshape</a> how we build cities, form families, and secure our future.



It might ask us to be more careful in the ways we manage resources, structure <a href="https://www.earth.com/news/dogs-healthcare-needs-change-as-they-enter-old-age/" target="_blank" rel="noreferrer noopener">health care</a>, and plan our economies. Planners, policymakers, and communities may need to think ahead, beyond simply counting heads.



The end of nonstop population growth might signal the beginning of a new kind of progress, where success is measured not by the number of people, but by how well we care for one another.



The full study is published in <a href="https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(24)00550-6/fulltext">The Lancet</a>.



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Global population decline predicted -- what Earth will be like with less people

The number of humans inhabiting the Earth has steadily increased...

Ingenuity, NASA's pioneering Mars helicopter, marked an unprecedented milestone in aviation history when it became the first aircraft to take flight on another world.



Its journey came to an end on January 18, 2024, with a final flight that concluded an era of extraordinary achievements.



<h2 class="wp-block-heading" id="h-journey-into-the-unknown">Journey into the unknown</h2>



A team of engineers at <a href="https://www.jpl.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA’s Jet Propulsion Laboratory</a> in Southern California, in partnership with AeroVironment, has given us an exclusive, behind-the-scenes look into the final voyage of the Ingenuity Mars Helicopter.



Originally designed as a technology demonstration to carry out five experimental test flights over a 30-day period, the helicopter surpassed all expectations. 



The little explorer stayed operational for nearly three years, conducted 72 flights, and expanded its flight range 30 times beyond what was initially planned - tallying more than two hours in flight time.



<h2 class="wp-block-heading" id="h-the-final-ascent-ingenuity-rising-against-gravity">The final ascent: Ingenuity rising against gravity</h2>



The <a href="https://www.earth.com/news/mars-ingenuity-the-first-helicopter-on-the-red-planet-ends-mission-after-3-years/" target="_blank" rel="noreferrer noopener">72nd flight</a>, which we now know as the final one, was planned as a short, vertical hop to assess the flight systems and capture images of the surrounding area.



The data sent back from the flight paints a picture of Ingenuity as it ascended to a height of 40 feet (12 meters), hovered, and took photographs.



The descent was initiated at the 19-second mark, and by the 32nd second, the helicopter had touched down, halting communication. 



It would not be until the next day that contact was re-established with the mission, and images transmitted six days after the flight showed the damage sustained by Ingenuity's <a href="https://www.earth.com/image/16-ingenuitys-rotors/" target="_blank" rel="noreferrer noopener">rotor</a> blades.



<h2 class="wp-block-heading" id="h-unraveling-the-mystery-what-went-wrong">Unraveling the mystery: What went wrong?</h2>



Investigating an accident from a 100-million-mile distance is no easy feat. Without the convenience of the usual "black boxes" or eyewitnesses, the investigators had to rely solely on the data and images transmitted back.



“While multiple scenarios are viable with the available data, we have one we believe is most likely: lack of surface texture gave the navigation system too little information to work with,” explained Håvard Grip, Ingenuity’s first pilot. 



The helicopter's vision navigation system was designed to track visual features on a flat terrain. It worked with impressive accuracy for Ingenuity's first five flights, but flight 72 found the helicopter in an area of Jezero Crater that was filled with relatively featureless, steep sand ripples.



This terrain confused the navigation system, preventing it from providing the velocity estimates necessary for safe landing. 



The resulting navigation errors created high horizontal velocities at touchdown, which led the helicopter to pitch and roll. 



The strain of the rapid landing snapped off all four rotor blades at their weakest point. This resulted in excessive vibration which finally severed the communication.



<h2 class="wp-block-heading" id="h-the-legacy-continues-ingenuity-s-contributions">The legacy continues: Ingenuity's contributions</h2>



Although permanently grounded, Ingenuity's contributions have not ended. It continues to transmit weather data and avionics test data to the Perseverance rover on a weekly basis. 



This information could prove invaluable for future <a href="https://www.earth.com/news/mars-missions-prepare-intense-solar-storms-coming-red-planet/" target="_blank" rel="noreferrer noopener">Red Planet</a> explorations. In addition, lessons from the Ingenuity project have sparked research into future <a href="https://www.earth.com/news/mars-gravity-pulls-earth-closer-to-the-sun-warming-our-climate-scientists-say/" target="_blank" rel="noreferrer noopener">Mars</a> helicopters.



"Because Ingenuity was designed to be affordable while demanding huge amounts of computer power, we became the first mission to fly commercial, off-the-shelf cell phone processors in deep space," said Teddy Tzanetos, Ingenuity's project manager.



Tzanetos also noted that almost four years of continuous operation suggested that not everything on Mars needed to be bigger, heavier, and radiation-hardened in order to function.



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



Inspired by Ingenuity, NASA engineers have been testing smaller, lighter avionics for vehicle designs, particularly for the <a href="https://www.earth.com/news/air-samples-from-mars-could-reveal-fascinating-secrets/" target="_blank" rel="noreferrer noopener">Mars Sample Return</a> campaign. 



The data from Ingenuity is also assisting engineers in developing the concept for a future Mars helicopter.



This new venture, currently named Chopper, is approximately 20 times heavier than Ingenuity, is designed to carry several pounds of scientific equipment, and is expected to explore remote Martian locations while traveling up to 2 miles (3 kilometers) in a day.



Ingenuity has broadened our horizons about the future of interplanetary flight. "Ingenuity has given us the confidence and data to envision the future of flight at Mars," concluded Tzanetos.



Information for this article was sourced from the <a href="https://www.jpl.nasa.gov/news/nasa-performs-first-aircraft-accident-investigation-on-another-world/" target="_blank" rel="noreferrer noopener">Jet Propulsion Laboratory</a>.



Image Credit: NASA/JPL



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NASA investigates an aviation accident on another planet

Ingenuity, NASA's pioneering Mars helicopter, marked an unprecedented milestone in...

The deepest parts of Earth's oceans have mostly remained a mystery, mainly because current technology on sea vessels cannot easily map every trough and chasm scattered around the planet.



Traditional methods tend to rely on slow and expensive ship-based surveys and, even after decades of effort, vast expanses of the ocean floor remain unknown. These blind spots have limited our understanding of underwater landscapes, the growth of tectonic structures, and the habitat ranges of strange marine creatures that lurk far below.



<h2 class="wp-block-heading" id="h-using-satellites-to-map-the-ocean-floor">Using satellites to map the ocean floor</h2>



<a href="https://www.nist.gov/how-do-you-measure-it/our-world/how-do-you-measure-depth-ocean" target="_blank" rel="noreferrer noopener">Shipborne sonar</a>, while effective, is far too time-consuming when considering the scale of <a href="https://www.earth.com/news/north-atlantic-ocean-has-a-memory-that-lasts-up-to-20-years/" target="_blank" rel="noreferrer noopener">Earth’s oceans</a>. Over a century would pass before the entire seabed could be charted this way. Sensors placed on satellites represent a much faster approach, relying on tiny variations in sea surface height to infer submarine features. 



For the past several decades, this <a href="https://topex.ucsd.edu/marine_grav/explore_grav.html" target="_blank" rel="noreferrer noopener">radar-altimeter</a>-based approach has allowed scientists to produce seafloor maps at moderate resolution. A collaboration between <a href="https://www.nasa.gov" target="_blank" rel="noreferrer noopener">NASA</a> and <a href="https://swot.cnes.fr/en/SWOT/index.htm" target="_blank" rel="noreferrer noopener">CNES</a> launched the Surface Water and Ocean Topography (<a href="https://swot.jpl.nasa.gov/" target="_blank" rel="noreferrer noopener">SWOT</a>) mission, a new satellite tool capable of measuring ocean surface heights in unprecedented detail. One year later, the first robust results began to roll in, and were <a href="https://pubmed.ncbi.nlm.nih.gov/39666787/" target="_blank" rel="noreferrer noopener">analyzed</a> by <a href="https://yaoyu9404.github.io/" target="_blank" rel="noreferrer noopener">Yao Yu</a> at the <a href="https://scripps.ucsd.edu/" target="_blank" rel="noreferrer noopener">Scripps Institution of Oceanography</a>, University of California, San Diego (UCSD).



<h2 class="wp-block-heading" id="h-previously-hidden-details">Previously hidden details</h2>



Improved data uncovered thousands of <a href="https://www.earth.com/news/earths-oceans-are-rapidly-changing-colors-matching-climate-predictions/" target="_blank" rel="noreferrer noopener">undersea</a> peaks that were previously unrecorded. Some are only a few miles across, but these features influence currents, nutrient flow, and the movements of certain aquatic populations. “So, one year of SWOT data beat the past 30 years of traditional radar-altimeter [data] in constructing marine gravity,” said Yao Yu, a Schmidt AI in Science Postdoctoral Fellow at <a href="https://ucsd.edu/" target="_blank" rel="noreferrer noopener">UCSD</a>. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/12/SWOT-satellite_seafloor_mapping_major-advance_credit-EOS_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/12/SWOT-satellite_seafloor_mapping_major-advance_credit-EOS_1s.webp" alt="Using satellite altimetry data from SWOT, scientists have created a global map of marine gravity, uncovering thousands of new seamounts. (Eötvös is a unit that measures the ocean’s vertical gravity gradient.) Credit: Yao Yu, Yu et al., 2024" class="wp-image-1954024"/></a><figcaption class="wp-element-caption">Using satellite altimetry data from SWOT, scientists have created a global map of marine gravity, uncovering thousands of new seamounts. (Eötvös is a unit that measures the ocean’s vertical gravity gradient.) Credit: Yao Yu, Yu et al., 2024</figcaption></figure>



The more finely tuned view reveals intricate ridges and valleys that traditional methods missed. These fresh insights help scientists understand how underwater landforms might affect tsunami speed and direction, and whether they attract clusters of unique organisms preferring specific conditions found around submerged peaks.



<h2 class="wp-block-heading" id="h-why-does-this-matter">Why does this matter?</h2>



Each submarine hill, canyon, or volcanic mount has its own story. Researchers can piece together histories of plate movements and infer where tectonic changes might happen next. This sharper perspective matters for navigators who need safe passages, and marine planners who keep an eye on resource extraction. 



Detailed underwater maps allow for better simulation of <a href="https://www.earth.com/news/collapse-of-main-atlantic-ocean-circulaton-current-amoc-is-already-happening/" target="_blank" rel="noreferrer noopener">ocean</a> circulation models, ensuring that climate forecasts gain subtle accuracy. “I am mostly impressed with the ability to [map] abyssal hills and seamounts so much [more clearly] than ever before,” said <a href="https://orbit.dtu.dk/en/persons/ole-baltazar-andersen" target="_blank" rel="noreferrer noopener">Ole Baltazar Andersen</a>, senior research scientist at the Technical University of Denmark.



<h2 class="wp-block-heading" id="h-giant-leap-for-ocean-maps">Giant leap for ocean maps</h2>



Before satellites and sonar, sailors dropped <a href="https://seahistory.org/sea-history-for-kids/leadline/" target="_blank" rel="noreferrer noopener">weighted lines</a> overboard and counted fathoms as the rope slipped through their hands. Today, radar and altimetry techniques provide scientists with more versatile options. Specialized altimeters aboard satellites, like SWOT, measure the time taken for radio pulses to bounce back from the surface.



This gives a rough sketch of the seafloor’s gravitational pull, revealing dips and bumps that mirror what lies beneath. In combination with ship-based measurements, <a href="https://www.star.nesdis.noaa.gov/socd/lsa/AltBathy/" target="_blank" rel="noreferrer noopener">satellite altimetry</a> grants a global perspective. It is not as direct as a ship’s sonar, but it covers enormous swaths of ocean in a fraction of the time.



<h2 class="wp-block-heading" id="h-real-world-benefits-of-ocean-mapping">Real world benefits of ocean mapping</h2>



Fresh ocean floor maps do not only quench our scientific curiosity. Improved <a href="https://www.star.nesdis.noaa.gov/socd/lsa/AltBathy/" target="_blank" rel="noreferrer noopener">bathymetry</a> can aid climate research. 



Ocean circulation involves currents moving cold, deep water upward, influencing carbon storage and heat distribution. If certain underwater hills guide these flows, slight improvements in understanding those features can refine models that predict future climate trends. 



More precise knowledge of the seabed’s shape might also help researchers anticipate where essential fisheries could flourish or fail.



“Improved seafloor mapping at such level of details opens new frontiers,” said <a href="https://science.nasa.gov/people/nadya-vinogradova-shiffer-physical-oceanography-program/" target="_blank" rel="noreferrer noopener">Nadya Vinogradova Shiffer</a>, Ocean Physics Program Director at NASA Headquarters in Washington, DC.



At a time when climate adaptation plans often depend on robust environmental data, these clearer images contribute to more informed <a href="https://www.earth.com/news/surprise-study-some-scientists-call-for-halting-ocean-plastic-cleanup-efforts/" target="_blank" rel="noreferrer noopener">decision-making</a>.



<h2 class="wp-block-heading" id="h-global-push-to-chart-everything">Global push to chart everything</h2>



A range of groups and organizations worldwide have pursued projects like <a href="https://seabed2030.org/" target="_blank" rel="noreferrer noopener">Seabed 2030</a>, aiming to map Earth’s entire underwater landscape by the end of the decade. 



Crowdsourced data, philanthropic funding, and cutting-edge technology promise richer, more accessible marine charts. Some researchers rely on <a href="https://www.saildrone.com/news/seabed-2030-partnership-to-map-the-ocean" target="_blank" rel="noreferrer noopener">small autonomous vessels</a>, armed with multibeam sonar, to scan sections of the ocean that remain unexplored. Others use advanced machine learning tools to process existing data and enhance resolution. This collective pursuit is essential for narrowing knowledge gaps that still puzzle those trying to map the shifting ocean conditions.



<h2 class="wp-block-heading" id="h-evolving-strategies-new-capabilities">Evolving strategies, new capabilities</h2>



Modern technology continues to advance. Older satellites captured <a href="https://eos.org/articles/new-seafloor-map-only-25-done-with-6-years-to-go" target="_blank" rel="noreferrer noopener">less detail</a>, but updated radar altimeters are more sensitive. 



The slight gravitational field changes caused by undersea mountains produce minuscule tilts in the ocean’s surface, and newer instruments register those subtle differences. These improved measurements help scientists see features that previously blended into the noise of raw data. 



More precise measurements transform the way experts look at ocean floor contours, enabling them to find patterns connected to everything from energy resources to hidden ecological hotspots.



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



Better ocean maps redefine what scientists consider ordinary. Areas once thought to be empty seascapes are now known to hold small peaks and ridges that matter to ocean life. With sharper detail, previously unknown zones might turn out to be critical habitats or hold clues to past geological events that affected climate and biodiversity. 



Each newly revealed feature expands what is known about oceanic processes.



The aim is not just to tally ridges or canyons. Clearer images allow more thorough interpretations that factor into navigation, resource management, environmental protection, and scientific exploration.



The next few years will likely bring even more refined altimetry missions, advanced sonar methods, and creative approaches that combine all types of datasets. 



Over time, these efforts will build towards an era when the planet’s underwater domain is no longer as cryptic.



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NASA maps Earth's ocean floors from space in stunning detail

The deepest parts of Earth's oceans have mostly remained a...

Shrubs are a key factor in the challenging task of restoring forests after catastrophic wildfires. Beyond planting new tree seedlings, it’s essential to determine when and where to plant for the best chance of success.



Recent research from the <a href="https://www.ucdavis.edu/" target="_blank" rel="noreferrer noopener">University of California, Davis</a> highlights how shrubs can significantly influence the success of forest recovery, acting as both allies and competitors in the regrowth process.



<h2 class="wp-block-heading" id="h-shrubs-competing-with-trees">Shrubs competing with trees </h2>



"Generally, where there are more shrubs, the climate and soil are more hospitable for <a href="https://www.earth.com/news/rising-temperatures-alter-photosynthesis-and-plant-growth/" target="_blank" rel="noreferrer noopener">plant growth</a>," noted Derek Young, the lead author of the research paper. "But what that also means is there’s more competition for trees.”



In regions with higher shrub populations, it seems that planting seedlings within a year of a wildfire might yield the best results. These seedlings will then have a head start before the woody shrubs begin to repopulate the area.



Conversely, in areas where shrubs are scarce, the most effective time to plant is reportedly three years after a fire, which gives soil conditions time to stabilize and recover from the intense heat of the <a href="https://www.earth.com/news/record-breaking-wildfire-years-are-just-getting-started/" target="_blank" rel="noreferrer noopener">wildfire</a>.



<h2 class="wp-block-heading" id="h-the-dual-role-of-shrubs-in-forest-recovery">The dual role of shrubs in forest recovery</h2>



Shrubs often act as ecological engineers, modifying their environment in ways that can either benefit or hinder <a href="https://www.earth.com/news/initiatives-to-plant-billions-of-trees-threatened-by-seedling-undersupply/" target="_blank" rel="noreferrer noopener">tree seedlings</a>. 



On one hand, their roots help stabilize soil and prevent erosion, which is especially vital after a wildfire. 



On the other hand, shrubs compete with tree seedlings for water, nutrients, and sunlight, creating challenging conditions for growth.



This dual role makes it critical to understand the specific ecosystem dynamics before implementing large-scale <a href="https://www.earth.com/news/half-of-plants-used-in-reforestation-projects-do-not-survive/" target="_blank" rel="noreferrer noopener">reforestation</a> efforts.



<h2 class="wp-block-heading" id="h-shrubs-shade-and-tree-growth">Shrubs, shade, and tree growth</h2>



Another interesting insight from the study is that in extremely harsh post-fire conditions, existing plant life might actually support the growth of new tree seedlings.



Shrubs, in particular, can provide shade, which reduces soil temperatures and protects fragile seedlings from excessive sun exposure.



“Some vegetation in those really harsh sites might actually facilitate tree establishment by providing shade,” said Young.



This finding challenges the common assumption that shrubs are always detrimental to tree growth, and suggests that they can play a protective role in certain environments.



<h2 class="wp-block-heading" id="h-optimizing-forest-recovery-after-fires">Optimizing forest recovery after fires</h2>



In a rapidly warming world, understanding how to effectively promote forest recovery is of vital importance.



Wildfires are growing more intense and frequent, leaving vast areas of scorched land in need of restoration.



“We’re aiming to help optimize <a href="https://www.earth.com/news/could-tree-planting-warm-earth-science-behind-albedo-effect/" target="_blank" rel="noreferrer noopener">tree planting</a> by targeting it to where it’s really needed. Doing this matters because we’re facing a reforestation backlog – limited capacity to replant and a lot of severely burned area,” explained study senior author Andrew Latimer.



This research provides a roadmap for making more strategic decisions about where, when, and how to plant trees in wildfire-affected areas.



<h2 class="wp-block-heading" id="h-learning-from-the-past-to-guide-the-future">Learning from the past to guide the future</h2>



The team’s study involved an extensive survey of areas in California’s Sierra Nevada, representing a range of climates and management strategies. 



These regions were replanted with conifer tree seedlings one to three years after experiencing intense wildfires.



To gather data, the researchers created circular plots measuring 400 square meters, including both replanted and non-planted areas. 



By meticulously counting seedlings, measuring shrub cover, and analyzing environmental variables, the team was able to quantify how different factors influence forest composition and tree survival rates.



<h2 class="wp-block-heading" id="h-mapping-the-path-to-recovery">Mapping the path to recovery</h2>



One of the most fascinating outcomes of the study is the development of predictive models that allow researchers to map where trees are likely to thrive post-wildfire.



“Now we have quantified the effects of certain environmental variables that allow us to make those maps,” Young said.



Future experiments will explore the effects of removing shrubs two years after a fire to observe how it influences tree regeneration. 



The team also plans to use drones and aerial imagery to monitor wildfire sites and assess the long-term impact of various management strategies over the past four decades.



<h2 class="wp-block-heading" id="h-balancing-the-future-of-forest-management">Balancing the future of forest management</h2>



As wildfires continue to reshape landscapes across the globe, balancing the role of shrubs in forest recovery becomes increasingly important. 



While shrubs may initially seem like obstacles, they can also serve as partners in reforestation, especially in areas with extreme environmental conditions.



This research provides valuable insights for land managers, conservationists, and policymakers working to restore forests in the era of climate change.



By understanding the complex interplay between shrubs and trees, we can create more resilient and sustainable ecosystems for the future.



The full study was published in the journal <a href="https://www.sciencedirect.com/science/article/abs/pii/S0378112724006583?via%3Dihub" target="_blank" rel="noreferrer noopener">Forest Ecology and Management</a>.



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Shrubs play a dual role in forest recovery following wildfires

Shrubs are a key factor in the challenging task of...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Nushagak Bay, a large estuary in southwest Alaska. Nushagak runs mainly north to south and exits in Bristol Bay, a large body of water in the Bering Sea.



"The bay is primarily fed by the Nushagak River, which begins in the Alaska Range and flows southwest approximately 450 km. The bay is also fed by several additional rivers including the Wood, Igushik, Snake and Weary rivers," says ESA.



"The dark colors of the Nushagak River are most likely due to tannins or lignins (chemical substances found in plants). Tannins and lignins from roots, leaves, seeds, bark and soil can leach into the water and give it a brown or even black colour. The sediments then flow southwards where it is mixed with the bluer waters of the bay."



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

[sendtonews key="0ynNMYkMKa-2340414-12187" type="single"] Today’s Video of the Day from the...

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> (ACS) reveals that proteins on flu viruses are actually flexible, tilting and waving in a “breath-like” motion. According to the experts, these proteins could be used to better defend against the flu.



"The main antigenic targets of influenza virus are two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). Whereas the structural and dynamical properties of both glycoproteins have been studied previously, the understanding of their plasticity in the whole-virion context is fragmented," wrote the researchers.



To investigate, the team conducted detailed simulations of the influenza A H1N1 virion, or the swine flu. The experts concluded that the visualizations show many new vulnerable states of flu viruses, which could improve future vaccines and antiviral drugs.



Video/ Image Credit: American Chemical Society&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Flu viruses are more flexible than expected

[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Lake Trasimeno, which is located west of Perugia in central Italy. It is the fourth largest lake in the country. While Trasimeno’s water level varies, it has a maximum depth of approximately six meters.&nbsp;



"In this Copernicus Sentinel-2 image, captured on 6 August 2022, the lake’s emerald green colour is likely due to the presence of phytoplankton. Streaks in the water, particularly visible in the west, indicate the presence of soil and sediments which have been stirred up by winds. Dark colored waters in the southern part of the lake indicate a presence of submerged and floating macrophytes (aquatic plants) as well as algae," says ESA.



"Surrounded by hills on three sides, Trasimeno is subject to heavy storms created by winds, especially from the north and west. There are three islets in the lake: Maggiore, Minore and Polvese (the largest). The lake’s shores are sparsely inhabited with only two popular villages: Castiglione del Lago and Passignano sul Trasimeno."



"Italy is experiencing its worst drought in 70 years which has affected drinking water supplies, hydroelectric power and agricultural production. High temperatures, hot winds and lack of rainfall are the main causes of drought in the Umbrian region which saw Lake Trasimeno’s drop 1.3 m, reaching the limit of the hydrometric zero in July 2022."



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> describes a new self-powered nanosensor that can instantly detect mercury contamination with the tap of a finger.&nbsp;



The oxidized form of mercury can be harmful when it is ingested through contaminated water or food. This makes it necessary for experts to develop sensors that can quickly and accurately detect the presence of mercury.&nbsp;



Zong-Hong Lin and colleagues have now created a triboelectric nanosensor (TENS) that can detect mercury by simply by touching a sample. According to the researchers, their TENS could serve as the basis for similar devices to safely and remotely monitor other pollutants.



Video Credit: American Chemical Society&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Detecting mercury contamination with the tap of a finger

[sendtonews key="LvS8v8bp9z-2564889-12187" type="single"] Today's Video of the Day from the...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Kainji Lake, a reservoir on the Niger River.



In 1968, Kainji Lake was created by the construction of the Kainji Dam. The Niger River, the third longest in Africa, enters the lake in the north.&nbsp;



According to <a href="https://www.earth.com/news/rivers-in-the-american-west-are-a-lifesaving-resource-for-birds/">ESA</a>, the creation of the lake submerged Foge Island and the town of Bussa and permanently flooded other riverine settlements, leaving around 50,000 people displaced.&nbsp;



Large parts of Foge Island are temporarily exposed during low water tides, and the land is often used by migrating fishermen. Kainji Dam is a dam across the Niger River in Niger State of Central Nigeria. 



Wild mammals occur at relatively low densities due to illegal hunting. Lake Kainji has suffered a dramatic decline as a fishery due to the high numbers of artisanal and subsistence fisherfolk using the lake. It has been suggested that a period of closure, together with controlled fishing rights may help improve fish stocks.



Kainji Lake National Park is the oldest of its kind in Nigeria. The park contains three distinct areas: a part of the Kainji Lake, the Borgu Game Reserve to the west of the lake, and the Zugurma Game Reserve to the southeast. The park is home to around 65 mammal species, 350 bird species, and 30 species of reptiles and amphibians. 



Video/ Image Credit: European Space Agency&nbsp;



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Kainji Lake in north central Nigeria

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Today’s Video of the Day from <a href="https://www.igb.illinois.edu/">Carl R. Woese Institute for Genomic Biology</a> reveals how scientists can modify common crops like soybean, rice, and wheat to protect them from heat stress.



“We need to double crop production by 2050 to feed a growing global population, and not only are we not on track to do that, but climate change is further complicating things,” said Amanda Cavanagh, a lecturer at the University of Essex. 



The study is part of Realizing Increased Photosynthetic Efficiency (RIPE), an international research project that aims to develop food crops that turn the sun’s energy into food more efficiently.



“Using an engineering approach we designed multiple alternative metabolic pathways to photorespiration. Testing them in the field showed increases in productivity which led Amanda to significantly move the project forward by showing our engineered plants can withstand pretty extreme temperature stress,” said study co-author and RIPE researcher Paul South.&nbsp;



“As the climate changes and temperature stresses increase the pressure on our global food supply, farmers will need every tool available including engineering approaches like the synthetic biology used here to maintain safe and productive harvests.”



The experts tested plants modified to have more efficient photorespiration to see if they were better adapted to warmer temperatures.&nbsp;



The team found that the engineered plants produced 26 percent more biomass than the wild-type plants exposed to the same temperatures, and had 15 percent less yield loss under the higher temperatures.



Video Credit: Amanda Nguyen/University of Illinois



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Designing crops that can beat the heat

[sendtonews key="QGPzYnXEtN-1712599-12187" type="single"] Today’s Video of the Day from Carl...

Today&#8217;s Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features wildflowers blooming in the desert region of the Carrizo Plain National Monument in southern California.&nbsp;



According to NASA, the region’s arid open spaces have been flooded by a &#8216;seasonal spectacle&#8221; of flowers after an unusually wet winter turned into spring.



The Theodore Payne Foundation for Wild Flowers &amp; Native Plants is a non-profit organization based in Los Angeles.



During a large bloom of wildflowers in the Carrizo Plain in 2019, the foundation described a typical scene: “There are currents of goldfields (Lasthenia californica) and splashes of blue valley phacelia (Phacelia ciliate) bobbing around in the yellow sea, while the smaller tidy tips (Layia platyglossa) try to find an island of soil not filled with taller flowers.&#8221;



&#8220;Desert candle (Caulanthus inflatus) can be found sprinkled about as well. The recommended viewing spots for all of this colorful bloom is along Soda Lake Road.”



Superblooms of large wildflowers occur sporadically in southern California, says NASA.



&#8220;By tracking online media coverage of wildflower blooms and comparing the reports with rainfall patterns, University of California ecologists counted 10 separate superblooms in the nearby Anza-Borrego Desert over four decades. Nine of the 10 blooms occurred after winters when precipitation was higher than average.&#8221;



The image was captured on April 6, 2023 by the Operational Land Imager-2 (OLI-2) on Landsat 9.



Image Credit: NASA Earth Observatory



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

"Seasonal spectacle" of wildflowers in southern California 

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the Bezymianny volcano, which is located in Kamchatka, Russia. After weeks of small-scale explosions, the stratovolcano experienced a strong explosion on April 7, 2023. According to NASA, the eruption sent volcanic materials as high as 12 kilometers into the sky.



Bezymianny was not the only volcano that erupted recently on the far eastern Russian peninsula. Shiveluch, the northernmost active volcano in Kamchatka, erupted three days later on April 10. This explosion was even bigger, releasing a plume of ash and gas up to 20 kilometers high.&nbsp;



"Russia’s Kamchatka Peninsula is home to one of the most concentrated groups of active volcanoes in the world, so it is no surprise that volcanologists observe new minor explosions, fumaroles, and hot avalanches at one of the peninsula’s 29 active volcanoes virtually every day," says NASA.



"Far less common is for the Kamchatka Volcanic Eruption Response Team (KVERT) to report on two major explosive eruptions that blast volcanic material clear into the stratosphere within the same week."



Image Credit: NASA Earth Observatory



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.