Today's Image of the Day from NASA Earth Observatory features Hurricane Erin, the first major storm of the 2025 Atlantic hurricane season.&nbsp;



Hurricane Erin tore across the ocean, intensifying from a modest Category 1 storm into a ferocious Category 5 system in just over a day.&nbsp;



The <a href="https://www.earth.com/news/once-in-a-thousand-years-extreme-storms-are-becoming-much-more-frequent/">storm</a> stayed offshore, but its power rippled across the Caribbean and along the Eastern Seaboard, bringing dangerous weather to millions of people.



<h2 class="wp-block-heading" id="h-erin-s-massive-wind-field">Erin’s massive wind field</h2>



At its peak, Hurricane Erin grew into a truly massive storm - not just because of its strength, but due to how far its winds spread. 



The National Hurricane Center reported that hurricane-force winds extended roughly 575 miles from the storm’s center. That meant the storm’s reach was enormous, touching wide stretches of ocean and coastal regions even without making landfall.



Coastal regions braced as Erin sent pounding surf, intense rain, and strong winds to Puerto Rico, the Turks and Caicos Islands, the Bahamas, and U.S. states from Florida to New York.&nbsp;



<h2 class="wp-block-heading" id="h-rapid-intensification-of-hurricane-erin">Rapid intensification of Hurricane Erin</h2>



Erin reached hurricane strength on August 15 and then stunned forecasters with a rapid intensification rarely seen. 



By the following day, it had exploded into a Category 5 monster, with sustained winds topping out at 160 miles per hour northeast of Puerto Rico. That speed put it among the most powerful hurricanes ever recorded in the Atlantic.



“Several environmental factors facilitated Erin’s rapid intensification, including light wind shear and a compact storm structure, according to a blog post by meteorologist Bob Henson,” noted <a href="https://earthobservatory.nasa.gov/images/154694/hurricane-erin-roils-in-the-atlantic">NASA</a>.



Warm waters across the Atlantic served as fuel, and the storm’s swift pace over the ocean meant it didn’t churn away its own heat source. The combination gave Erin the perfect environment to gain <a href="https://www.earth.com/news/climate-change-has-amplified-hurricane-strength/">strength</a> almost overnight.



<h2 class="wp-block-heading" id="h-a-rare-and-early-event">A rare and early event</h2>



Erin joined a small group of storms in history. Since official records began in 1851, only 43 Atlantic hurricanes have reached Category 5.&nbsp;



Erin also stood out as the earliest storm of this intensity in its part of the basin. For scientists who track weather extremes, it was another reminder of how unusual <a href="https://www.earth.com/news/what-causes-the-rapid-intensification-of-hurricanes/">conditions</a> can line up to create powerful storms.



As the hurricane continued westward, it went through eyewall replacement cycles. This process often weakens peak wind speeds but spreads the force over a broader area.&nbsp;



By August 18, satellite images from NASA’s Terra spacecraft captured a strikingly clear eye, a hallmark of its strength even as it began to lose some intensity.



<h2 class="wp-block-heading" id="h-islands-feel-the-outer-bands">Islands feel the outer bands</h2>



Though Erin never came ashore, outer bands from the storm slammed into nearby islands. Puerto Rico endured heavy rain and high winds on August 17, leaving more than 147,000 customers without power.&nbsp;



Residents in the Turks and Caicos Islands and the Bahamas faced tropical storm conditions, with coastal flooding and strong wind gusts persisting into August 19.



These impacts showed how storms hundreds of miles offshore can still disrupt daily life, from flooded streets to downed power lines.



<h2 class="wp-block-heading" id="h-u-s-east-coast-on-alert">U.S. East Coast on alert</h2>



Forecasts projected Erin would curve northward and run parallel to the U.S. coast as a Category 2 <a href="https://www.earth.com/news/how-hurricanes-help-oceans-fight-climate-change/">hurricane</a>, with warnings stretching from Florida to Canada.



Officials across the region acted quickly. North Carolina’s Outer Banks came under an evacuation order, and the state declared a state of emergency.&nbsp;



In New York and New Jersey, authorities urged people to stay out of the ocean as conditions grew increasingly dangerous.&nbsp;



<h2 class="wp-block-heading" id="h-the-2025-hurricane-season">The 2025 hurricane season</h2>



Hurricane Erin may be the first of 2025, but experts expect more storms before the season ends.&nbsp;



<a href="https://www.earth.com/news/coastal-hurricanes-are-intensifying-faster-due-to-climate-change/">Warmer waters</a> and shifting weather patterns continue to set the stage for powerful hurricanes that could impact communities from the Caribbean to the Atlantic.&nbsp;



Erin’s sudden growth highlights the challenge of predicting storm behavior and the importance of staying prepared, even when landfall seems unlikely.



Image Credit: NASA Earth Observatory&nbsp;



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Hurricane Erin explodes into first Category 5 storm of 2025

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

Today's Image of the Day from NASA Earth Observatory features smoke plumes stretching across the Iberian Peninsula, as wildfires suddenly intensified across Spain and Portugal.



The image was captured on August 15 by the MODIS (Moderate Resolution Imaging Spectroradiometer) sensor on NASA’s Terra satellite.&nbsp;



<h2 class="wp-block-heading" id="h-record-breaking-fire-season-nbsp">Record-breaking fire season&nbsp;</h2>



Hot, dry conditions pushed fire risk to extreme levels, leaving vast landscapes scorched. The fires aren’t just dramatic visuals - they are shaping the year’s record-breaking <a href="https://www.earth.com/news/fire-weather-seasons-are-overlapping-more-than-ever-before/">fire season</a>.



“As of August 19, fires in Spain had scorched more than 382,000 hectares (944,000 acres) since the start of the year, according to the European Forest Fire Information System (EFFIS),” noted <a href="https://earthobservatory.nasa.gov/images/154691/smoke-blankets-the-iberian-peninsula" target="_blank" rel="noreferrer noopener">NASA</a>.



This exceeds any previous yearly total in the EFFIS records, which date back to 2006. Firefighters were stretched thin, tackling roughly 20 major blazes nationwide, with a particularly severe cluster near Ourense.



<h2 class="wp-block-heading" id="h-fire-devastation-in-portugal">Fire devastation in Portugal</h2>



Portugal faced a similarly devastating season. By mid-August, more than 347,000 hectares (857,000 acres) had been consumed by fire.&nbsp;



The European Commission’s Emergency Response Coordination Centre reported 10 large fires burning across the country at that time. The largest fire, near Trancoso, alone had already scorched over 39,000 hectares.



The blazes forced thousands of residents to evacuate their homes. Essential services were disrupted, including the high-speed rail line between Madrid and Galicia, which had been closed for nearly a week.&nbsp;



Firefighters worked tirelessly under extreme conditions, navigating both flames and smoke to protect people and property.



<h2 class="wp-block-heading" id="h-smoke-pollution-and-far-reaching-effects">Smoke, pollution, and far-reaching effects</h2>



The fires didn’t stay local. <a href="https://www.earth.com/news/wildfire-smoke-delivers-a-double-hit-to-air-quality/">Smoke</a> from the Iberian Peninsula carried high into the atmosphere, drifting across France, the United Kingdom, and Scandinavia.&nbsp;



It even mixed with smoke from wildfires in Canada, creating hazy skies across parts of Europe. Carbon emissions from these fires hit record levels in Spain and near-record levels in Portugal, according to the Copernicus Atmosphere Monitoring Service.



Black carbon, a component of fine particulate matter (PM2.5) released by wildfires, poses serious health risks. These tiny particles can penetrate deep into the lungs and enter the bloodstream, potentially aggravating respiratory and cardiovascular conditions.&nbsp;



Residents in affected regions were warned to limit outdoor activity and monitor air quality as smoke lingered.



<h2 class="wp-block-heading" id="h-wildfires-in-spain-and-portugal">Wildfires in Spain and Portugal </h2>



Spain and Portugal are no strangers to wildfires, but the 2025 season is unusual for its speed and scale.&nbsp;



Heatwaves have become more frequent in southern Europe, with <a href="https://www.earth.com/news/state-of-the-climate-2024-record-heat-and-rising-seas/">rising temperatures</a> and prolonged droughts creating tinderbox conditions for forests and grasslands.&nbsp;



Experts link this increase to ongoing climate change, which has amplified the intensity and frequency of extreme weather events in the region.



The EFFIS database shows that Spain’s burned area this year surpassed previous records, while Portugal’s figures ranked second only to the catastrophic fires of 2017. These trends highlight the growing challenge of managing wildfires in a warming climate.



<h2 class="wp-block-heading" id="h-the-human-toll-of-wildfires-nbsp">The human toll of wildfires&nbsp;</h2>



Beyond environmental impacts, <a href="https://www.earth.com/news/wildfires-are-changing-the-quality-of-our-air/">wildfires</a> take a heavy toll on communities. Tens of thousands of people have been displaced, and homes, farms, and critical infrastructure have suffered extensive damage.&nbsp;



Emergency services scrambled to coordinate evacuations and protect residents, while volunteers and local authorities provided support on the ground.



Firefighters faced particularly difficult conditions, battling flames under record heat and through thick <a href="https://www.earth.com/news/climate-change-is-making-wildfire-smoke-more-deadly/">smoke</a>. The work was physically demanding and dangerous.



<h2 class="wp-block-heading" id="h-satellite-technology-and-firefighting">Satellite technology and firefighting</h2>



NASA’s Terra satellite and the MODIS sensor provide crucial monitoring for wildfire activity. These tools allow authorities to track the spread of fires in near-real time, identify hotspots, and deploy resources more efficiently.&nbsp;



The data feeds into systems like EFFIS and the Fire Information for Resource Management System (FIRMS), offering a broader picture of wildfire patterns and trends across Europe.



This combination of satellite monitoring, on-the-ground firefighting, and coordination among emergency services is vital for managing the ongoing crisis. As wildfires continue to grow in frequency and intensity, technology can help limit damage and protect communities.



Image Credit: NASA Earth Observatory&nbsp;



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Wildfires scorch Spain and Portugal amid extreme heat

Today's Image of the Day from NASA features the spiral galaxy NGC 2566, which is located 76 million light-years away in the constellation Puppis. 



The striking image was captured by the NASA/ESA Hubble Space Telescope.



“A prominent bar of stars stretches across the center of this galaxy, and spiral arms emerge from each end of the bar. Because NGC 2566 appears tilted from our perspective, its disk takes on an almond shape, giving the galaxy the appearance of a cosmic eye,” said <a href="https://phys.org/news/2024-12-hubble-spies-spiral-galaxy-ngc.html" target="_blank" rel="noreferrer noopener">NASA</a>.



“As NGC 2566 appears to gaze at us, astronomers gaze right back, using Hubble to survey the galaxy's star clusters and star-forming regions.”



<h2 class="wp-block-heading" id="h-complex-appearance-of-ngc-2566">Complex appearance of NGC 2566</h2>



NGC 2566 lies at a considerable distance from Earth, making it a challenging object for amateur astronomers to observe in detail without powerful telescopes.&nbsp;



It can be seen in the Southern Hemisphere sky and is better observed from locations with minimal <a href="https://www.earth.com/news/how-light-pollution-influences-interest-in-astronomy/">light pollution</a>. 



The galaxy's arms are populated with young, bright stars, regions of active star formation, and interstellar gas and dust - giving it a dynamic and complex appearance.



<h2 class="wp-block-heading" id="h-measuring-the-ages-of-stars">Measuring the ages of stars</h2>



According to NASA, data from Hubble is especially valuable for studying stars that are just a few million years old. “These stars are bright at the ultraviolet and visible wavelengths to which Hubble is sensitive.”



“Using these data, researchers can measure the ages of NGC 2566's stars, which helps piece together the timeline of the galaxy's star formation and the exchange of gas between star-forming clouds and the stars themselves.”



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



Star formation in <a href="https://www.earth.com/news/shapes-of-one-million-galaxies-hint-at-the-universes-origins/">galaxies</a> is a fascinating and complex process that unfolds over millions of years. It begins in vast clouds of gas and dust, known as molecular clouds, which are often found in the spiral arms of galaxies or in regions of irregular or starburst galaxies. 



These clouds provide the raw material for star formation, consisting primarily of hydrogen and helium, with trace amounts of heavier elements.



As the molecular clouds collapse under their own gravity, regions within them begin to condense and fragment, forming dense clumps. Within these clumps, protostars emerge. Their formation is driven by the gravitational pull drawing in surrounding gas.&nbsp;



During this process, the gas heats up due to increasing pressure, eventually igniting nuclear fusion in the core, signaling the birth of a new star.



<h2 class="wp-block-heading" id="h-rates-of-star-formation">Rates of star formation</h2>



The rate of star formation varies across galaxies is influenced by numerous factors. In spiral galaxies like the Milky Way, star formation is most active in the spiral arms, where density waves compress gas and dust, triggering the collapse of molecular clouds.&nbsp;



Elliptical galaxies, which often have little cold gas and dust, typically exhibit low rates of star formation or none at all.



On the other hand, starburst galaxies experience episodes of exceptionally high star formation, often triggered by <a href="https://www.earth.com/news/webb-captures-a-galaxy-collision-with-a-radiant-smile/">galactic collisions</a> or interactions.



These events can funnel large amounts of gas into central regions, leading to intense star-forming activity. However, such bursts are usually short-lived on cosmic timescales, exhausting the available gas quickly.



The environment within a galaxy also plays a significant role. Stellar winds and supernova explosions from existing stars can both inhibit and promote star formation. They may disperse gas, preventing further collapse, or compress nearby clouds, triggering new star formation.&nbsp;



As galaxies evolve over time, the availability of gas diminishes, leading to a gradual decline in star formation activity.



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



The Puppis constellation in the southern sky represents the stern of a ship. It was once part of a larger constellation known as Argo Navis, which depicted the mythical ship of Jason and the Argonauts.&nbsp;



However, Argo Navis was later divided into three separate constellations: Puppis, Carina (the keel), and Vela (the sails). Puppis is the largest of these three and contains many notable celestial objects.



This constellation is home to several bright stars, including Naos (Zeta Puppis), a hot, massive star that emits intense ultraviolet radiation. Puppis also hosts a wide variety of deep-sky objects, such as open <a href="https://www.earth.com/news/stunning-star-clusters-captured-in-the-extreme-outskirts-of-the-milky-way/">star clusters</a> and nebulae. 



Among these, Messier 46 and Messier 47 stand out. Both are beautiful star clusters that are visible through binoculars or small telescopes. The region is dense with stars because it lies along the <a href="https://www.earth.com/news/milky-way-collision-may-change-everything-we-know-about-our-galaxy/">Milky Way</a>, making it a prime area for stargazing and astrophotography. 



Image Credit: NASA



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Eye in the sky: A galaxy that appears to be gazing back

Today's Image of the Day from NASA features the spiral...

Today's Image of the Day from NASA Earth Observatory features a large phytoplankton bloom in the Gulf of Maine.



The image was captured on June 21, 2025, by the Ocean Color Instrument (OCI) on NASA’s PACE satellite.&nbsp;



“In summer 2025, waters in the Gulf of Maine popped with vivid swirls of blue and green. The cause was a massive bloom of phytoplankton - microscopic plant-like organisms that often float near the ocean surface,” noted <a href="https://earthobservatory.nasa.gov/images/154472/a-booming-bloom-returns-to-the-gulf-of-maine">NASA</a>.



“Scientists say it was one of the largest blooms of its kind to show up in the Gulf’s waters in recent years.”



<h2 class="wp-block-heading" id="h-bloom-in-the-gulf-of-maine">Bloom in the Gulf of Maine </h2>



Catherine Mitchell is a satellite oceanographer at Bigelow Laboratory for Ocean Sciences. She noted that the Gulf of Maine bloom contained coccolithophores, a type of <a href="https://www.earth.com/news/tiny-phytoplankton-that-feed-ocean-life-are-rapidly-disappearing/">phytoplankton</a> that makes the water appear milky blue.



“The tiny organisms, along with other types of phytoplankton, including diatoms that bloom here in spring, lie at the base of the marine food web,” explained NASA.



“Their presence - or absence - in Gulf of Maine waters can affect the entire ecosystem, from finfish to shellfish, and the region’s fisheries that depend on them.”



<h2 class="wp-block-heading" id="h-shifting-conditions-and-plankton-communities-nbsp">Shifting conditions and plankton communities&nbsp;</h2>



Mitchell said that coccolithophore blooms like this one became less common in the Gulf’s waters starting around 2010. But in recent years, they’ve started to come back.&nbsp;



Scientists have also seen more dinoflagellates (a type of phytoplankton that move with tiny tails) and an overall drop in phytoplankton productivity over the past few decades.



These changes in plankton are linked to shifting ocean conditions. For instance, heavy rainfall from 2006 to 2009 made the Gulf’s waters fresher. Then, starting in 2008, <a href="https://www.earth.com/news/invisible-forest-of-phytoplankton-thrives-in-a-warming-climate/">warm water</a> from deep in the North Atlantic began heating the Gulf from the bottom up.&nbsp;



However, by spring 2025, bottom-water temperatures were cooler than they’ve been in 20 years.



<h2 class="wp-block-heading" id="h-ongoing-research-efforts">Ongoing research efforts</h2>



“The relationship between these changing water conditions and phytoplankton communities in the gulf remains unclear, but ongoing research could begin to provide some answers,” noted NASA.



“In fact, Mitchell and colleagues scrutinized this PACE image just days before heading out on a research expedition to study the bloom and other ocean properties up close. The cruise, the third so far this year, offers scientists the chance to validate ocean color data collected by PACE with real-world ocean samples.”



Mitchell pointed out that a major benefit of the PACE satellite is its ability to “see the rainbow,” which makes it easier for scientists to distinguish between groups of phytoplankton.



“With our continuing field measurements, we will validate ocean color observations from PACE, enabling satellite observations in the Gulf of Maine and supporting the region’s fisheries and aquaculture industries.”



<h2 class="wp-block-heading" id="h-vital-signs-of-ocean-health">Vital signs of ocean health</h2>



<a href="https://www.earth.com/news/dust-from-africa-sparked-a-massive-phytoplankton-bloom/">Phytoplankton blooms</a> like the one captured in the Gulf of Maine are vital signs of ocean health. These microscopic organisms form the foundation of marine food webs, feeding everything from tiny zooplankton to large fish, whales, and seabirds.&nbsp;



When conditions are right - such as warm temperatures, abundant sunlight, and available nutrients - phytoplankton populations can grow rapidly, creating colorful blooms that are visible from space.



The Gulf of Maine is particularly sensitive to environmental change. Located at the intersection of cold northern currents and warmer waters from the south, it’s a dynamic ecosystem where small shifts in temperature or salinity can have outsized effects.&nbsp;



This region is also one of the fastest-warming ocean areas on the planet, with <a href="https://www.earth.com/news/ocean-temperatures-are-rising-faster-than-expected-and-likely-to-accelerate/">temperatures</a> rising more than three times the global ocean average in some years.



<h2 class="wp-block-heading" id="h-forecasting-changes-with-ocean-monitoring-nbsp">Forecasting changes with ocean monitoring&nbsp;</h2>



Changes in water temperature and salinity have ripple effects across the food chain. Warmer waters can favor certain types of phytoplankton over others, shifting the balance of species in ways that affect what fish and shellfish are available to predators - and to the region’s fisheries.&nbsp;



For example, coccolithophores may thrive in clearer, warmer waters, while traditional spring-blooming diatoms do better in colder, more nutrient-rich conditions.



Long-term monitoring is essential to understand and predict these shifts. Satellites like PACE provide a global view of ocean color, which reflects the presence and composition of phytoplankton.&nbsp;



By combining these observations with ship-based sampling, scientists can get a more complete picture of how plankton communities are evolving and how that affects everything from carbon cycling to fisheries sustainability.



<h2 class="wp-block-heading" id="h-warming-in-the-gulf-of-maine-nbsp">Warming in the Gulf of Maine&nbsp;</h2>



The Gulf’s warming trend has already caused noticeable ecological changes. Some species of fish have moved farther north or into deeper waters in search of cooler temperatures.&nbsp;



Lobsters, a key commercial species, have shifted their range as well. Meanwhile, harmful <a href="https://www.earth.com/news/green-algae-in-lake-erie-may-be-hiding-toxic-deadly-compounds/">algal blooms</a> - caused by certain types of phytoplankton - have become more frequent in some parts of the Gulf, threatening shellfish harvests and public health.



Scientists are working to better predict how blooms will respond to future climate conditions.&nbsp;



Understanding which species are likely to dominate under warmer, fresher, or more acidic conditions can help predict changes in fish stocks, shellfish safety, and ecosystem stability.&nbsp;



This kind of forecasting is especially important in the Gulf of Maine, where marine resources are closely tied to local economies.



Image Credit: NASA Earth Observatory&nbsp;



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Giant bloom in the Gulf of Maine signals change

Today's Image of the Day from NASA Earth Observatory features Lake Chad in central Africa. The photograph was taken by an astronaut on the International Space Station.



According to <a href="https://earthobservatory.nasa.gov/images/154407/lake-chads-water-wetlands-and-dunes" target="_blank" rel="noreferrer noopener">NASA</a>, Lake Chad once ranked among the largest natural lakes in the world. It was a critical resource for millions of people and animals, supporting agriculture and fishing across the region.&nbsp;



Lake Chad straddles the borders of Chad, Nigeria, Niger, and Cameroon. The shallow <a href="https://www.earth.com/news/lakes-are-warming-toward-the-point-of-no-return/">lake</a> is primarily fed by the Chari River, which brings water from the Central African Republic. 



The water levels are also influenced by seasonal rainfall. The rainfall patterns vary significantly across the basin but generally follow a wet-dry seasonal cycle.



<h2 class="wp-block-heading" id="h-environmental-decline-and-shrinkage-nbsp">Environmental decline and shrinkage&nbsp;</h2>



From the 1960s to the early 2000s, the lake lost more than 90 percent of its surface area. It transformed from a vast expanse of open water into a patchwork of wetlands, reed beds, and scattered pools.&nbsp;



This environmental decline has had severe consequences for local communities, leading to food and <a href="https://www.earth.com/news/global-water-security-relies-on-the-origins-of-rainfall/">water insecurity</a>, loss of livelihoods, and increasing competition over scarce resources.



“Ongoing droughts and the rising demand for fresh water have shrunk the lake to less than a tenth of the area it covered in the middle of the last century,” noted NASA.



“Although the lake has experienced dry and wet periods for thousands of years, there has been a significant decline in the amount of lake water available since the 1960s.”



<h2 class="wp-block-heading" id="h-conflict-culture-and-economy">Conflict, culture, and economy</h2>



Lake Chad is a geopolitical hotspot. The region has been affected by conflict, including the insurgency led by Boko Haram, which has displaced millions and further complicated efforts to manage and protect the lake’s fragile ecosystem.&nbsp;



Despite these challenges, regional governments and international organizations are working to restore and sustain the lake, including ambitious proposals to divert water from the Congo River basin.



Culturally and economically, Lake Chad remains vital. It is a hub for trade and social exchange among diverse ethnic groups and continues to provide fish and fertile land despite its reduced size.&nbsp;



The future of Lake Chad hinges on sustainable water management, <a href="https://www.earth.com/news/climate-extremes-alter-how-sunlight-travels-through-clear-lakes/">climate</a> resilience, and political cooperation across national boundaries.



<h2 class="wp-block-heading" id="h-evolution-of-lake-chad-nbsp">Evolution of Lake Chad&nbsp;</h2>



According to NASA, the evolution of Lake Chad has been documented by astronaut photography over the past 60 years.&nbsp;



“During the Apollo 7 mission in 1968, an astronaut acquired an oblique <a href="https://eol.jsc.nasa.gov/SearchPhotos/photo.pl?mission=AS07&amp;roll=8&amp;frame=1932" target="_blank" rel="noreferrer noopener">photograph</a> of the lake as one large body of water. In 1982, another photo from the space shuttle mission STS-5 recorded receding water levels and encroaching sand dunes.”



“A photo taken in 2015 during space station Expedition 42 captured the lake’s remaining waters and wetlands in dark green, blue, and brown, contrasting with the sandy shades of the surrounding land.” 



<h2 class="wp-block-heading" id="h-wildlife-of-lake-chad">Wildlife of Lake Chad</h2>



Lake Chad still supports wildlife, though species diversity and abundance have declined significantly due to ecosystem degradation



The lake and its surrounding wetlands are home to several species of fish, including tilapia, catfish, and Nile perch, which are important both ecologically and economically.&nbsp;



These fish support a major regional fishing industry, although overfishing and changes in water conditions have put pressure on fish populations.



Birds are another key component of the ecosystem. The lake serves as a crucial habitat and stopover point for <a href="https://www.earth.com/news/birds-may-be-using-quantum-physics-for-migration/">migratory birds</a> traveling along the African-Eurasian flyway. 



Species such as herons, storks, ducks, and geese can be found in the region, especially during the wet season when parts of the lake flood and create rich feeding grounds.



Mammals that depend on the surrounding floodplains and wetlands include hippos and various antelope species, yet their numbers have declined.&nbsp;



<h2 class="wp-block-heading" id="h-conservation-efforts-and-challenges">Conservation efforts and challenges</h2>



Reptiles like Nile crocodiles and turtles also inhabit the lake's waters and marshy areas. In the past, larger wildlife such as elephants and lions may have roamed the wider Lake Chad basin, but they are now mostly gone from the immediate lake area due to habitat loss and human activity.



Despite these challenges, Lake Chad remains an important, yet increasingly fragile, refuge for wildlife in a region where water and natural habitats are becoming more scarce.&nbsp;



Conservation efforts aim to balance the needs of people and <a href="https://www.earth.com/news/thousands-of-freshwater-species-are-threatened-with-extinction/">wildlife</a>, but the success of such efforts depends on managing the lake’s limited resources in the face of climate change, political instability, and population growth.



Image Credit: NASA Earth Observatory&nbsp;



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Lake Chad: A vanishing lifeline in Central Africa

The most complete view yet of the human genome has arrived, and it tackles the messy parts scientists used to skip. 



The new work assembles nearly all of the repeat-rich, shape-shifting DNA that helps explain disease risk and drug response across different people.



It is not a single tidy sequence, but rather 65 complete genomes drawn from diverse ancestries and resolved with unusual clarity. 



That scale and quality move the field toward practical use in precision medicine, where care adjusts to each person’s <a href="https://www.earth.com/news/missing-parts-of-the-human-genome-have-finally-been-decoded/">genetic</a> wiring.



<h2 class="wp-block-heading" id="h-uncovering-dna-s-hidden-changes">Uncovering DNA’s hidden changes</h2>



The hardest regions to read are home to structural <a href="https://www.earth.com/news/scientists-discover-an-organism-that-defies-the-definition-of-life-sukunaarchaeum/">variants</a>. These include large insertions, deletions, inversions, duplications, and translocations that often change how genes work. 



If you ignore these variants, risk models fall short, and rare disease diagnoses stall. Getting them right is the difference between a vague genetic hint and a confident clinical answer.



The study was co-led by Christine Beck of The Jackson Laboratory and <a href="https://health.uconn.edu/" target="_blank" rel="noreferrer noopener">UConn Health</a>, as part of the Human Genome Structural Variation Consortium (<a href="https://www.internationalgenome.org/human-genome-structural-variation-consortium/" target="_blank" rel="noreferrer noopener">HGSVC</a>).



<h2 class="wp-block-heading" id="h-what-the-genome-map-shows">What the genome map shows</h2>



Across 130 haplotypes, the team reports closing 92 percent of the assembly gaps that lingered after earlier references and bringing 39 percent of chromosomes to telomere to telomere status. 



That level of finish lets researchers track long, tangled stretches end to end instead of guessing across voids.



The experts resolved 1,852 previously intractable complex structural variants that older methods could not untie. 



The team also validated 1,246 human centromeres - the control hubs needed for proper chromosome segregation in cell division. These regions long stymied assemblies because of their repeating DNA.



<h2 class="wp-block-heading" id="h-sequences-that-rewire-gene-activity">Sequences that rewire gene activity</h2>



The team cataloged 12,919 insertions from transposable elements, the mobile <a href="https://www.earth.com/news/ground-oaks-genetic-secrets-may-inspire-new-medicines-and-pesticides/">sequences</a> that can rewire gene activity - accounting for nearly 10 percent of all structural variation detected here. 



This catalog turns what used to be background noise into an interpretable signal for disease studies.



The research provides contiguous sequences for the immune related Major Histocompatibility Complex (MHC), along with other regions that influence digestion and development. Each of those regions matters directly to diagnosis or treatment decisions in clinics.



<h2 class="wp-block-heading" id="h-representation-matters-in-genetics">Representation matters in genetics</h2>



For many years, genetic reference data left out large parts of the world’s population. This new study was designed to address that gap by creating a more inclusive and complete resource.



Only recently has technology advanced enough to allow scientists to sequence entire genomes without the large gaps that once limited the field. 



Using these tools, researchers estimate they can now capture more than 95 percent of structural variants within each genome they study.



<h2 class="wp-block-heading" id="h-hard-places-practical-payoffs">Hard places, practical payoffs</h2>



The MHC carries dense immune variation associated with more than 100 human diseases, so fully charting it helps clinicians weigh risk with more nuance across populations. 



When the reference is biased or incomplete, those associations skew toward the few ancestries that dominate the data.



The study delivers complete sequences for the following genes: SMN1 and SMN2, which are the drug targets in spinal muscular atrophy. That matters because therapies like nusinersen improve infant survival, and better maps speed diagnosis and treatment eligibility.



The researchers also finished especially stubborn parts of the <a href="https://www.earth.com/news/y-chromosome-is-disappearing-may-already-be-causing-problems-for-men/">Y chromosome</a>, building on a 2023 effort that first produced a gapless Y sequence. 



Closing and comparing many Ys provides cleaner baselines for fertility research and forensic work that depend on those repeats and palindromes.



<h2 class="wp-block-heading" id="h-building-a-global-genome-map">Building a global genome map</h2>



This breakthrough research stands on two recent pillars. In 2022, the Telomere to Telomere Consortium published the first complete sequence of a single human genome. 



This achievement proved that full chromosomes were feasible with the latest approaches.



In 2023, the Human Pangenome Reference expanded representation by assembling 47 individuals from many ancestries - a shift from a one genome yardstick to a family of references that reflect global diversity.



<h2 class="wp-block-heading" id="h-the-genome-map-and-health">The genome map and health</h2>



When reference genomes miss common variations, clinical pipelines struggle. Expanding structural variant catalogs improves read mapping, variant calling, and interpretation. 



Ultimately, this strengthens rare disease diagnosis and risk prediction across ancestries.



When a rearrangement sits next to a dosage-sensitive gene or flips an enhancer away from its target, the biological effect can be large, and it can be missed by short-read tools. This study makes those events visible at a scale that finally matches clinical need.



<h2 class="wp-block-heading" id="h-the-moving-parts-of-genomes">The moving parts of genomes</h2>



The new assemblies also clarify how endogenous <a href="https://www.earth.com/news/ancient-viruses-can-reactivate-and-fuel-cancer-development/">retroviruses</a> and other transposable elements to contribute regulatory switches.



Recent work shows that long terminal repeats from ancient viruses form distinct subfamilies with their own enhancer motifs. These motifs can rise or fall across primate lineages in ways that influence gene regulation.



At everyday scales, the finished amylase region helps connect gene dosage to diet. People from high starch diet populations tend to carry more copies of salivary amylase - an example of structural variation with clear physiological impact.



<h2 class="wp-block-heading" id="h-what-s-next-for-the-genome-map">What’s next for the genome map</h2>



Open methods and shared datasets mean other teams can now reach the same level of completeness. That is essential if the benefits of precision medicine are going to reach everyone, not just those already overrepresented in <a href="https://www.earth.com/news/giant-dormant-virus-punuivirus-discovered-in-algae-could-revolutionize-gene-editing/">genetic research</a>.



The muscle, immune, and neurodevelopmental regions that used to be black boxes are now spelled out with far fewer interruptions. This clarity sets a new bar for reference genomes, clinical pipelines, and the science that connects DNA to health outcomes.



The study is published in the journal <a href="https://www.science.org/doi/10.1126/sciadv.ads9164" target="_blank" rel="noreferrer noopener">Nature</a>.



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New human genome map could transform medicine

The most complete view yet of the human genome has...

In the depths of&nbsp;Costa Rica’s tropical forests, a surprising story has emerged. Spectral bats - the world’s largest carnivorous bats - are not the solitary hunters many once believed them to be. Instead, these creatures lead richly social lives, filled with affection, cooperation, and care.



A new study led by Marisa Tietge at the&nbsp;<a href="https://www.museumfuernaturkunde.berlin/en" target="_blank" rel="noreferrer noopener">Museum für Naturkunde</a> - Leibniz Institute for Evolution and Biodiversity Science&nbsp;in Germany has revealed remarkable details about their behavior. The findings, published in&nbsp;PLOS One, provide the first clear window into the private world of these elusive animals.



<h2 class="wp-block-heading" id="h-hidden-cameras-capture-bat-lives">Hidden cameras capture bat lives</h2>



Studying bats is never simple. Their <a href="https://www.earth.com/news/geomagnetic-disturbances-throw-nocturnal-birds-off-course/">nocturnal</a> lifestyle and hidden roosts make close observation challenging. 



To overcome this, the researchers installed a motion-sensitive infrared camera inside a hollow tree in Guanacaste, Costa Rica. Here, a family of four spectral bats (Vampyrum spectrum) became the focus of months-long monitoring.



These bats, with wingspans reaching up to three feet, were once thought to forage alone. But three months of footage told a different story - one of social cooperation and emotional bonds.



<h2 class="wp-block-heading" id="h-rare-affection-documented">Rare affection documented</h2>



The researchers observed that the bats displayed eight distinct behaviors, ranging from grooming and vocal exchanges to playful interactions and even a unique form of greeting. 



In this greeting, one bat would wrap its wings around another in a gesture resembling a hug, a form of physical affection rarely documented in wild carnivorous species.



Beyond social gestures, food sharing also emerged as a central behavior. Adult bats returning from hunts often transferred their prey to younger members of the <a href="https://www.earth.com/news/bats-have-acoustic-mental-maps-to-navigate-total-darkness/">colony</a>. 



This not only provided nourishment but also served as a form of training, allowing the younger bats to practice handling prey.



At the same time, it eased their gradual transition from relying on milk to consuming a carnivorous diet, preparing them for independence as skilled hunters.



<h2 class="wp-block-heading" id="h-family-cooperation-revealed">Family cooperation revealed</h2>



Surprisingly, the recordings captured instances of cooperative foraging. Adults sometimes left or returned to the roost together, and males transferred prey to females nursing young. 



These behaviors suggest teamwork, which is a rarity among carnivorous mammals. The observations also revealed a long-term family structure. 



The presence of two young bats, likely born in different years, showed that offspring may remain with parents longer than expected. This hints at extended parental care beyond what is typical for many bat species.



<h2 class="wp-block-heading" id="h-complex-bonds-and-care">Complex bonds and care</h2>



The study paints a picture of spectral bats as deeply connected <a href="https://www.earth.com/news/bats-dont-get-cancer-now-scientists-think-they-know-the-reason/">animals</a>. Both parents participate in raising the young, forming strong monogamous bonds and investing heavily in offspring survival. 



Such biparental care is uncommon in bats and especially rare among carnivorous mammals.



“Spectral bats exhibit a level of cooperative behavior and biparental care that is rarely documented in bats - a fascinating area for future research,” Tietge said. “We were astonished by how gentle and cooperative these apex predators are.” 



“The most endearing behavior was forming a tight cuddle-ball when falling asleep: each bat wrapping one wing around its nearest neighbor, all snouts touching.”



<h2 class="wp-block-heading" id="h-spectral-bats-even-recognize-humans">Spectral bats even recognize humans</h2>



Their social complexity extended beyond family life. Tietge herself experienced something extraordinary. 



"I was astonished to find that the bats seemed to recognize me after several consecutive weeks of visiting the roost," she said. "At first, I was greeted with threat-like calls, and the bats broke their roosting formation to hide in the corners." 



"But over time, their response shifted to just a few curious looks - no <a href="https://www.earth.com/news/marmosets-call-each-other-by-names-with-distinct-vocalizations/">vocalizations</a>, and they remained in a relaxed roosting formation. Even after nine months away, they appeared to recognize me immediately when I returned the following season."



<h2 class="wp-block-heading" id="h-what-spectral-bats-teach-us">What spectral bats teach us</h2>



These findings transform our understanding of spectral bats. Rather than solitary hunters, they appear as nurturing creatures that rely on cooperation and affection.



“Rather than hunting and raising young in isolation,&nbsp;V. spectrum&nbsp;shows complex cooperation behavior, strong <a href="https://www.earth.com/news/birds-show-signs-of-divorce-before-the-breeding-season/">monogamous pair</a> bonds, as well as extended parental investment and biparental care - traits highly unusual in carnivorous mammals, especially bats,” Tietge concluded.



The study is published in the journal <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0321338" target="_blank" rel="noreferrer noopener">PLOS One</a>.



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Spectral bats lead social lives with hugs, play, and food sharing

In the depths of&nbsp;Costa Rica’s tropical forests, a surprising story...

Slimy layered microbial mats in Shark Bay are more than seaside oddities. They are living laboratories where bacteria and archaea still work side by side, much as they may have done long ago.



A new co-culture from these mats shows a bacterium and an archaeon physically connecting through tiny tubes while trading metabolites in ways that make both partners tick. That kind of teamwork fits neatly with ideas about how complex <a href="https://www.earth.com/news/life-was-thriving-before-earths-greatest-mass-extinction/">cells</a> arose.



<a href="https://www.unsw.edu.au/staff/brendan-burns" target="_blank" rel="noreferrer noopener">Brendan P. Burns</a> at the University of New South Wales (UNSW) led the study with colleagues including <a href="https://profiles.uts.edu.au/Iain.Duggin" target="_blank" rel="noreferrer noopener">Iain G. Duggin</a> at the University of Technology Sydney.



<h2 class="wp-block-heading" id="h-shark-bay-microbes-survive-extremes">Shark Bay microbes survive extremes</h2>



Shark Bay, Western Australia, holds thriving stromatolites, the rock-like piles that grow when layered microbial communities trap and bind sediments in harsh, salty water. 



In Malgana language, Shark Bay is called <a href="https://www.nature.com/articles/srep46160" target="_blank" rel="noreferrer noopener">Gathaagudu</a>, which means two waters, a name still used by Traditional Owners and regional agencies.



The southern basin can be roughly twice as salty as the open ocean, and the mats ride out heat, desiccation, and intense UV under those conditions. 



Modern mats are not time capsules, but they are useful stand-ins for ancient ecosystems where <a href="https://www.earth.com/news/rocks-reveal-the-turning-point-when-oxygen-changed-earth-forever/">microbes</a> built layered structures and forged partnerships that shaped the planet.



<h2 class="wp-block-heading" id="h-microbial-mat-microbes-team-up">Microbial mat microbes team up</h2>



Back in the lab, researchers enriched a two-member community from those mats: the bacterium Stromatodesulfovibrio nilemahensis and a newly named Asgard archaeon, Nerearchaeum marumarumayae. 



<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5875740/" target="_blank" rel="noreferrer noopener">Asgard archaea</a> are widely viewed as the closest known prokaryotic relatives of eukaryotes, the lineage that includes animals, plants, and fungi.



The team sequenced both genomes and grew the partners under high-salt, low-oxygen settings that fit the mats’ tough environment. 



Each partner seems to cover what the other lacks, a classic sign of syntrophy, where two microbes share metabolic tasks to make <a href="https://www.earth.com/news/timeline-of-lifes-evolution-extended-by-nearly-1-5-billion-years/">life</a> work.



<h2 class="wp-block-heading" id="h-genes-show-nutrient-sharing">Genes show nutrient sharing</h2>



Genome analysis indicates the archaeon releases hydrogen, acetate, formate, and sulfite, while the bacterium supplies amino acids and vitamins that the archaeon needs. 



These characteristics and interactions may represent an early step in the symbiotic evolution of <a href="https://www.britannica.com/science/eukaryote" target="_blank" rel="noreferrer noopener">eukaryotic</a> cells.



That statement does not claim a perfect replay of early evolution. It argues that the features they see line up with long-standing models that link archaeal hydrogen producers and bacterial sulfate reducers to the rise of complex cells.



Those models gained traction after the first enrichment and later formal isolation of an Asgard archaeon, <a href="https://www.microbiologyresearch.org/content/journal/ijsem/10.1099/ijsem.0.006435" target="_blank" rel="noreferrer noopener">Prometheoarchaeum syntrophicum</a>, a slow-growing anaerobe that depends on partner microbes.



<h2 class="wp-block-heading" id="h-microbial-mat-shows-nanotube-connections">Microbial mat shows nanotube connections</h2>



With cryotomography, the researchers observed chains of budded vesicles attached to the archaeal cell by extracellular fibers, plus internal tube and cage-like elements inside the archaeon. 



They also saw intercellular nanotubes apparently assembled by the bacterium that contact the archaeal surface, hinting at direct physical links during resource sharing.



Archaea in other systems build similar connections, and a 2024 <a href="https://www.nature.com/articles/s41467-024-51159-2" target="_blank" rel="noreferrer noopener">study</a> reported nanotubes in a co-culture that bridged cytoplasms and appeared to serve as conduits for molecular exchange. 



That study counted an average of 4.4 nanotubes per host-symbiont contact, showing how dense and structured these links can become under the microscope.



<h2 class="wp-block-heading" id="h-hints-at-complex-cells">Hints at complex cells</h2>



If partners swap metabolites through persistent contacts, selection can push them toward tighter dependence. 



That is the kind of ratchet some researchers think nudged early archaea and bacteria toward the cell-in-cell <a href="https://www.earth.com/news/third-state-of-existence-beyond-life-and-death-confirmed-by-scientists/">arrangement</a> that defines eukaryotes.



The new Shark Bay culture does not show one cell engulfing the other. It does, however, put plausible building blocks on the table: complementing metabolisms, physical tethers, and vesicle traffic that could knit cells into a more integrated unit over time.



That interpretation sits alongside earlier work that first enriched and then formally described Prometheoarchaeum, strengthening the case that Asgard lineages sit near the root of eukaryotic features.



More broadly, archaeal communities are <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10117752/" target="_blank" rel="noreferrer noopener">known</a> to trade vesicles and tube-like structures, which can shuttle proteins, lipids, and genetic material and may help build cooperative networks in extreme habitats.



<h2 class="wp-block-heading" id="h-next-steps-in-research">Next steps in research</h2>



First, replication matters. Independent teams will want to reproduce the nanotube contacts and metabolite exchanges and test whether those tubes move specific molecules in real time, not just correlate with growth.



Second, comparative context helps. Asgard cultures and co-cultures are slowly expanding, and every new system gives biologists another angle on the relationship between archaeal cell biology and eukaryotic traits.



Finally, place still matters. Shark Bay’s mats are rugged, hypersaline, sunlit, and dynamic, a mix of stresses that can reward tight microbial alliances and keep them around across seasons and storms.



The study is published in <a href="https://www.biorxiv.org/content/10.1101/2025.07.22.663070v2" target="_blank" rel="noreferrer noopener">bioRxiv</a>.



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Strange microbial bedfellows offer clues to how complex life evolved

Slimy layered microbial mats in Shark Bay are more than...

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