Today's Image of the Day from NASA Webb Images features an extraordinary view of Uranus, the seventh planet from the sun in our solar system.&nbsp;



The photo reveals the rings, moons, and extreme seasons of the ice giant Uranus in unprecedented detail.&nbsp;



<h2 class="wp-block-heading" id="h-dynamic-north-polar-cap-nbsp">Dynamic north polar cap&nbsp;</h2>



“The Webb image exquisitely captures Uranus’s seasonal north polar cap, including the bright, white, inner cap and the dark lane in the bottom of the polar cap,” noted NASA.



Unlike Earth, where polar ice caps are formed by the freezing of water, Uranus's polar caps are thought to be primarily composed of a dense concentration of haze in the atmosphere.&nbsp;



The polar cap's haze is likely composed of methane particles. Methane in Uranus's atmosphere condenses into ice particles, which then create a thick haze that scatters sunlight, giving the polar cap its distinct bright appearance in visible and infrared light.



The polar cap is dynamic and changes over time. It becomes more prominent during the summer season of each pole. 



As Uranus moves along its orbit, the cap's appearance transforms, with the haze becoming thicker and brighter when the pole is in continuous sunlight.



<h2 class="wp-block-heading" id="h-the-zeta-ring-nbsp">The Zeta ring&nbsp;</h2>



The inner and outer rings of Uranus are visible in the image, including Zeta - the innermost ring which is the faintest and most difficult to observe.



The <a href="https://www.earth.com/news/stunning-photo-of-uranus-and-its-rings-and-moons-captured-by-the-webb-telescope/" target="_blank" rel="noreferrer noopener">rings of Uranus</a> are primarily composed of narrow bands of particles, likely made of water ice mixed with a dark material. These rings are distinct from those of Saturn in that they are much darker and narrower.



The faintness and characteristics of the Zeta ring make it a subject of interest in studies related to the dynamics and composition of planetary ring systems.



<h2 class="wp-block-heading" id="h-moons-of-uranus-nbsp">Moons of Uranus&nbsp;</h2>



The <a href="https://science.nasa.gov/mission/webb/multimedia/images/" target="_blank" rel="noreferrer noopener">Webb</a> photo also features nine of the planet’s <a href="https://www.earth.com/news/nasa-four-uranus-moons-may-have-oceans-that-are-miles-deep/" target="_blank" rel="noreferrer noopener">moons</a>, which appear as blue dots surrounding the rings.&nbsp;



“Clockwise starting at 2 o’clock, they are: Rosalind, Puck, Belinda, Desdemona, Cressida, Bianca, Portia, Juliet, and Perdita. The orbits of these moons share the 98-degree tilt of their parent planet relative to the plane of the solar system,” noted NASA.



Uranus has 27 known moons, and they are divided into three main groups based on their orbits: the inner moons, the major moons, and the irregular moons.



The <a href="https://www.earth.com/news/uranus-moon-ariel-may-have-a-hidden-ocean/" target="_blank" rel="noreferrer noopener">moons</a> of Uranus are unique because they are named after characters from the works of William Shakespeare and Alexander Pope, rather than being named after figures from classical mythology, as is common for the moons of other planets.



<h2 class="wp-block-heading" id="h-the-ice-giant-uranus-nbsp">The ice giant Uranus&nbsp;</h2>



Uranus is classified as an "ice giant" because, unlike the gas giants Jupiter and Saturn, which are primarily composed of hydrogen and helium, Uranus has a significant proportion of "ices" in its composition.&nbsp;



In astronomical terms, ices refer to volatile substances like water, ammonia, and methane, which exist in solid or liquid forms at the low temperatures found in the outer solar system.



Uranus has a thick atmosphere of hydrogen and helium, but beneath that, it contains a large, dense mantle composed of these ices, along with rock and other heavier elements.&nbsp;



The term <a href="https://www.earth.com/news/diamond-rain-may-be-common-on-giant-icy-planets/" target="_blank" rel="noreferrer noopener">ice giant</a> differentiates Uranus (and Neptune, the other ice giant) from the larger gas giants, emphasizing the different chemical compositions and internal structures of these planets.



<h2 class="wp-block-heading" id="h-climate-of-uranus-nbsp">Climate of Uranus&nbsp;</h2>



Uranus has a unique and extreme climate, largely influenced by its unusual tilt, which causes the planet to rotate almost on its side. This tilt leads to extreme seasonal variations, with each pole experiencing 42 years of continuous sunlight followed by 42 years of darkness.&nbsp;



Even though it is closer to the sun than Neptune, Uranus is the coldest planet in the solar system, with temperatures plunging to as low as -224°C (-371°F). The reason for this is not fully understood, but it might be due to an internal heat distribution anomaly.



Despite these frigid conditions, Uranus experiences intense weather patterns, including powerful storms and winds that can reach speeds of up to 900 kilometers per hour. These winds blow in the same direction as the planet’s rotation and are some of the fastest in the solar system.



Storms on Uranus are driven by its internal heat and the interaction of its <a href="https://www.earth.com/news/uranus-is-more-gassy-less-icy-than-we-ever-imagined/" target="_blank" rel="noreferrer noopener">atmospheric gases</a>. Observations have shown that these storms can be quite large, sometimes comparable in size to the Earth, and can last for several years.&nbsp;



The planet’s extreme axial tilt also means that the storms and weather patterns are highly variable, depending on the season. During equinoxes, when the Sun is directly over the equator, Uranus exhibits more storm activity compared to when the poles are pointed towards the Sun or away from it.



<h2 class="wp-block-heading" id="h-observations-of-uranus">Observations of Uranus</h2>



“One day on Uranus is about 17 hours, so the planet’s rotation is relatively quick. This makes it supremely difficult for observatories with a sharp eye like Webb to capture one simple image of the entire planet - storms and other atmospheric features, and the planet’s moons, move visibly within minutes,” explained NASA.



“This image combines several longer and shorter exposures of this dynamic system to correct for those slight changes throughout the observing time.”



The first recorded observations of Uranus were made by John Flamsteed on December 13, 1690. However, Flamsteed mistakenly identified the planet as a star, which he named “34 Tauri."&nbsp;



It wasn't until March 13, 1781, that Uranus was officially identified as a planet by William Herschel. He initially thought he had discovered a comet, but further observations and calculations by other astronomers confirmed that it was a new planet, making Uranus the first planet discovered in modern history with the aid of a telescope.



Image Credit: NASA, ESA, CSA, STScI



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The ice giant Uranus in stunning detail

Today's Image of the Day from NASA Webb Images features...

Today's Image of the Day from NASA Earth Observatory features a strong extratropical cyclone, which struck the Pacific Northwest on November 19, 2024.



“The storm knocked over trees and left nearly 600,000 people without power in Washington state on November 20, according to news reports,” noted <a href="https://search.app?link=https%3A%2F%2Fearthobservatory.nasa.gov%2Fimages%2F153605%2Fextratropical-cyclone-whips-over-the-pacific-northwest&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">NASA</a>. “This image shows the storm system at 1:50 p.m. Pacific Time on November 19.” 



According to NASA, mature extratropical cyclones like this often feature comma-shaped cloud patterns that are the product of ‘conveyor belt’ circulation. “Heavy precipitation is often present near the low-pressure head of the comma.”



<h2 class="wp-block-heading" id="h-impacts-of-the-extratropical-cyclone-nbsp">Impacts of the extratropical cyclone&nbsp;</h2>



The “bomb cyclone” brought <a href="https://search.app?link=https%3A%2F%2Fwww.earth.com%2Fnews%2Fhow-much-does-climate-change-influence-extreme-weather-events%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">severe weather</a>, including strong winds exceeding 70 mph, heavy rainfall, and snow in higher elevations. These conditions led to significant disruptions, including downed trees and hazardous travel conditions.



In urban and rural areas, damage to infrastructure and properties was substantial, with emergency responders and utility crews working around the clock to restore services.&nbsp;



Additionally, mountain passes faced dangerous blizzard conditions, with up to 20 inches of snow accumulating in some areas, severely affecting travel.



<h2 class="wp-block-heading" id="h-rapid-pace-of-acceleration">Rapid pace of acceleration</h2>



Chris Dolce is a meteorologist at The Weather Channel. He noted that on the evening of November 19, the storm’s central pressure dropped to levels on par with a storm in October 2021, which saw the lowest pressure in about 50 years of records for that region.



“The pace of the storm’s intensification was more than double the criteria for bombogenesis - a popular term that describes a midlatitude cyclone that rapidly intensifies into a ‘bomb cyclone,’” said NASA.



The rapidly dropping atmospheric pressure at the center of the <a href="https://search.app?link=https%3A%2F%2Fwww.earth.com%2Fnews%2Fcoastal-hurricanes-are-intensifying-faster-due-to-climate-change%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">storm</a> caused winds to intensify quickly. According to the National Weather Service in Seattle, wind gusts reached up to 77 miles per hour in the mountains southeast of the city.



“The cyclone kicked off a long-duration atmospheric river that forecasters expect will park over Northern California and southern Oregon through November 22. The National Weather Service estimates that these areas could see rainfall totals of 12 to 16 inches over the duration of the storm,” noted NASA.



<h2 class="wp-block-heading" id="h-what-is-an-extratropical-cyclone">What is an extratropical cyclone?</h2>



An extratropical cyclone is a large-scale weather system that forms outside the tropics, typically between 30° and 60° latitude, and is associated with areas of low pressure.&nbsp;



<h3 class="wp-block-heading" id="h-energy-source">Energy source</h3>



These cyclones obtain their energy from the contrast in temperature between air masses, such as cold polar air and warm subtropical air. This contrast creates instability and drives atmospheric circulation.



<h3 class="wp-block-heading" id="h-development-of-extratropical-cyclones-nbsp">Development of extratropical cyclones&nbsp;</h3>



Extratropical cyclones usually have well-defined warm and cold fronts. They often develop along the polar front, where cold and warm air masses meet.



A common area for their development is the mid-latitudes, particularly in regions like the North Atlantic and North Pacific.



<h3 class="wp-block-heading" id="h-weather-conditions">Weather conditions</h3>



Extratropical cyclones can bring a variety of <a href="https://search.app?link=https%3A%2F%2Fwww.earth.com%2Fnews%2Fhuman-activity-is-rapidly-changing-weather-in-north-america%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">weather conditions</a>, including heavy rain, snow, strong winds, and severe storms. They are responsible for much of the day-to-day weather in mid-latitude regions.



<h3 class="wp-block-heading" id="h-tropical-vs-extratropical-cyclones-nbsp">Tropical vs. extratropical cyclones&nbsp;</h3>



While <a href="https://search.app?link=https%3A%2F%2Fwww.earth.com%2Fnews%2Ffast-moving-tropical-cyclones-are-becoming-more-powerful%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">tropical cyclones</a> derive energy from warm ocean waters and have a warm core, extratropical cyclones gain energy from temperature contrasts and have a cold core.



Tropical cyclones typically lack fronts, whereas extratropical cyclones are defined by them.



These systems are essential in distributing heat and energy across the planet, playing a critical role in the Earth's climate system.



<h2 class="wp-block-heading" id="h-caught-off-guard-by-the-weather">Caught off guard by the weather</h2>



The bomb cyclone in the Pacific Northwest highlights the importance of <a href="https://search.app?link=https%3A%2F%2Fwww.earth.com%2Fnews%2Fnew-era-in-forecasting-ai-will-improve-extreme-weather-warnings%2F&amp;utm_campaign=aga&amp;utm_source=agsadl2%2Csh%2Fx%2Fgs%2Fm2%2F4" target="_blank" rel="noreferrer noopener">preparedness</a>, as residents were urged to secure loose outdoor items, stock emergency supplies, and avoid unnecessary travel.



The fire department in Bellevue, east of Seattle, posted a Severe Weather Safety alert on Facebook: “It’s severe out there. Trees are coming down all over the city, with multiple falling onto homes. If you are able, head to the lowest floor you can and stay away from windows. Do not go outside if you can avoid it.”



The image was captured by the VIIRS (Visible Infrared Imaging Radiometer Suite) on NOAA’s JPSS-1 (Joint Polar Satellite System-1).



Image Credit: NASA Earth Observatory



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Bomb cyclone rapidly intensified in the Pacific Northwest

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

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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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Spiral galaxy NGC 1559 is a loner in outer space

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

Today's Image of the Day from the European Space Agency features NGC 1792, a spiral galaxy located in the constellation Columba, about 43 million light-years away from Earth.&nbsp;



This galaxy, discovered by British astronomer James Dunlop in 1826, is part of the larger NGC 1808 group of galaxies.&nbsp;



<h2 class="wp-block-heading" id="h-intimate-view-of-ngc-1792">Intimate view of NGC 1792</h2>



“An orange glow radiates from the center of NGC 1792, the heart of this stellar forge. Captured by the NASA/ESA Hubble Space Telescope, this intimate view of NGC 1792 gives us some insight into this galactic powerhouse,” noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



“The vast swathes of tell-tale blue seen throughout the galaxy indicate areas that are full of young, hot stars, and it is in the shades of orange, seen nearer the center, that the older, cooler stars reside.”



<h2 class="wp-block-heading" id="h-vigorous-star-formation-nbsp">Vigorous star formation&nbsp;</h2>



NGC 1792 is notable for its vigorous star formation, classifying it as a starburst galaxy. This high rate of star formation is thought to be triggered by gravitational interactions with neighboring galaxies, though the exact cause is still under study.



“Nestled in the constellation of Columba (The Dove), NGC 1792 is both a spiral galaxy, and a starburst galaxy,” said ESA. “Within starburst galaxies, stars are forming at comparatively exorbitant rates. The rate of star formation can be more than 10 times faster in a starburst galaxy than in the Milky Way.”



<h2 class="wp-block-heading" id="h-fierce-bursts-of-star-formation">Fierce bursts of star formation</h2>



ESA noted that when galaxies have a large reservoir of gas, like NGC 1792, these short-lived starburst phases can be sparked by galactic events such as mergers and tidal interactions.&nbsp;



“One might think that these starburst galaxies would easily consume all of their gas in a large forming event. However, supernova explosions and intense stellar winds produced in these powerful starbursts can inject energy into the gas and disperse it.”&nbsp;



“This halts the star formation before it can completely deplete the galaxy of all its fuel. Scientists are actively working to understand this complex interplay between the dynamics that drive and quench these fierce bursts of star formation.”



Due to its distance and brightness, NGC 1792 can be observed with medium-sized telescopes under favorable conditions.



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



Galaxy evolution refers to the process by which galaxies form and change over time. It begins in the early universe, shortly after the <a href="https://www.earth.com/news/new-observations-disprove-big-bang-theory-universe-began-tired-light-theory/" target="_blank" rel="noreferrer noopener">Big Bang</a>, when small density fluctuations in the primordial gas led to the collapse of matter into the first galaxies. 



<h3 class="wp-block-heading" id="h-galaxy-mergers">Galaxy mergers</h3>



These early galaxies were small and irregular, composed mostly of gas and dark matter. Over billions of years, galaxies grew larger by merging with one another and by accreting gas from the surrounding space.&nbsp;



These interactions often triggered bursts of star formation, and collisions between galaxies sometimes led to the creation of new, more massive galaxies.



<h3 class="wp-block-heading" id="h-structural-changes">Structural changes</h3>



As galaxies evolve, their morphology - their shape and structure - can change. Early galaxies were often irregular or disk-shaped, but over time, many galaxies formed into the elliptical or spiral shapes we see today.&nbsp;



<h3 class="wp-block-heading" id="h-star-formation">Star formation</h3>



Star formation is a key driver of galaxy evolution, but it gradually slows down as galaxies age. 



The gas that fuels <a href="https://www.earth.com/news/black-hole-is-starving-its-host-galaxy-of-star-forming-fuel/" target="_blank" rel="noreferrer noopener">star formation</a> can be used up, or it can be heated and pushed out of galaxies by supernovae or black holes, reducing the galaxy's ability to form new stars.



<h3 class="wp-block-heading" id="h-galaxy-environment-nbsp">Galaxy environment&nbsp;</h3>



The environment in which a galaxy resides also plays a role in its evolution. Galaxies in dense clusters are more likely to interact with their neighbors, which can alter their shape or trigger bursts of star formation.&nbsp;



In contrast, galaxies in more isolated regions of space evolve more slowly and without as many dramatic interactions.



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



Dark matter also plays a crucial role in galaxy evolution. It provides the gravitational framework that holds galaxies together and influences their interactions with one another.&nbsp;



Supermassive <a href="https://www.earth.com/search-results/?search=Galaxies%20merge&amp;start=0" target="_blank" rel="noreferrer noopener">black holes</a>, found at the centers of most large galaxies, can also affect their evolution by releasing energy that impacts star formation and the movement of gas within the galaxy.



Overall, galaxy evolution is a complex and ongoing process driven by interactions between stars, gas, <a href="https://www.earth.com/news/study-dark-matter-does-not-exist-and-the-universe-is-27-billion-years-old/" target="_blank" rel="noreferrer noopener">dark matter</a>, and black holes, and shaped by both internal processes and external influences.



Image Credit: ESA/Hubble &amp; NASA, J. Lee



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NGC 1792: A galactic powerhouse 

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 IC 5332, which is located over 29 million light-years away from Earth.



The galaxy spans approximately 66,000 light-years in diameter. This makes it notably smaller than our <a href="https://www.earth.com/news/large-amount-of-dark-matter-may-be-missing-from-the-milky-way/" target="_blank" rel="noreferrer noopener">Milky Way</a>, which is just over 100,000 light-years in diameter. 



<h2 class="wp-block-heading" id="h-unprecedented-look-at-ic-5332">Unprecedented look at IC 5332</h2>



In a stunning photo release by NASA and ESA in 2022, the spiral galaxy IC 5332 was presented in an unprecedented level of detail. The images were captured by the <a href="https://www.earth.com/news/james-webb-captures-incredible-new-image-of-uranus/" target="_blank" rel="noreferrer noopener">James Webb Space Telescope</a>.



This feat was made possible through the use of the Mid-InfraRed Instrument (MIRI), which captures images in the mid-infrared spectrum.



<h2 class="wp-block-heading" id="h-unique-perspective-from-earth">Unique perspective from Earth</h2>



One of the most striking features of IC 5332, as revealed by these observations, is its almost perfect face-on orientation relative to Earth.&nbsp;



This unique perspective allows astronomers to clearly observe and admire the symmetrical arrangement of its spiral arms.



<h2 class="wp-block-heading" id="h-webb-unveils-ic-5332-in-new-light">Webb unveils IC 5332 in new light</h2>



The clarity of these images represents a significant advancement over previous observations made by the Hubble Space Telescope, which imaged IC 5332 in ultraviolet and visible light.&nbsp;



While Hubble’s images revealed the galaxy’s symmetrical spiral arms, James Webb’s MIRI has unveiled these structures as a complex web of gas that emits infrared light at various temperatures.



<h2 class="wp-block-heading" id="h-the-miri-instrument-on-james-webb-nbsp">The MIRI instrument on James Webb&nbsp;</h2>



Capturing this range of infrared light is no simple task. It requires highly specialized instruments that must be maintained at extremely cold temperatures.&nbsp;



The MIRI instrument on the James Webb Space Telescope is specifically designed for this purpose and performs exceptionally well. Its capabilities allow astronomers to see aspects of <a href="https://www.earth.com/news/james-webb-captures-galaxies-that-are-too-old-to-exist/" target="_blank" rel="noreferrer noopener">galaxies</a> that are otherwise hidden in other wavelengths.



The detailed images provided by MIRI offer more than just a visual spectacle; they provide valuable data about the composition and temperature of the gases that make up the spiral arms of IC 5332. 



This can help scientists understand the processes of star formation within the galaxy and how these processes compare to those in our own <a href="https://www.earth.com/news/stars-at-the-edge-of-our-milky-way-galaxy-travel-more-slowly/" target="_blank" rel="noreferrer noopener">Milky Way</a>.



<h2 class="wp-block-heading" id="h-webb-finds-hidden-features-of-the-universe-nbsp">Webb finds hidden features of the universe&nbsp;</h2>



The images of IC 5332 served as a critical test of the James Webb Space Telescope’s capabilities in observing the universe in infrared light. 



As astronomers continue to explore with Webb’s full suite of instruments, many more hidden features of the universe will be revealed.



The information provided by the <a href="https://www.earth.com/news/webb-telescope-discovers-second-most-distant-galaxy-in-pandoras-cluster/" target="_blank" rel="noreferrer noopener">James Webb Space Telescope</a> not only expands our understanding of the cosmos but also enhances our appreciation for the complex and beautiful structures that exist in our universe.&nbsp;



<h2 class="wp-block-heading" id="h-spiral-galaxies-like-ic-5332">Spiral galaxies like IC 5332</h2>



Spiral galaxies are some of the most visually striking objects in the universe, characterized by their rotating arms that extend from a central nucleus, giving them a distinct spiral appearance.&nbsp;



These galaxies are primarily made up of a flat, rotating disk containing stars, gas, and dust, and a central concentration of stars known as the bulge. These are often surrounded by a much fainter halo of stars, many of which reside in globular clusters.



Spiral galaxies differ from other galaxy types, such as elliptical and irregular galaxies, in their structure and content. 



The spiral arms are sites of ongoing star formation and are brighter than the rest of the disk because of the young, hot stars that are typically found there. The arms appear distinct because of their density waves, which compress the gas and dust, leading to star formation.



The rotation of the spiral arms also contributes to the galaxy's flat shape due to the centrifugal forces acting on the disk. The central bulge can vary in size and often contains older, red stars.&nbsp;



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



Some spiral galaxies have a bar-shaped structure that extends from the central bulge, making them barred spirals. This bar affects the motion of stars and gas within the galaxy and can influence star formation activity.



Spiral galaxies are an important focus of study because they contain a significant amount of visible matter and play a crucial role in understanding the formation and evolution of galaxies.&nbsp;



Their distinct features also make them particularly useful for studying the laws of physics under extreme conditions, such as high densities and velocities.



Image Credit: <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>/Webb, NASA &amp; CSA, J. Lee and the PHANGS-JWST and PHANGS-HST Teams



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Spiral galaxy IC 5332: A complex web of gas and light

Lewotolo volcano spews ash thousands of meters high. Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features Indonesia’s Lesser Sunda Islands, a group of islands in Maritime Southeast Asia.

On November 29, 2020, a powerful eruption of the Lewotolo volcano spewed an ash plume high in the air over the island of Lembata. The ash plume, which is visible in this image, reached thousands of meters high, shutting down the local airport. Lewotolo volcano spews ash thousands of meters high

The Lewotolo stratovolcano, also known as Mount Ile Lewotolok, has been relatively quiet since 2012.

The image was captured on November 29 by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite.

On 27 November, an eruption occurred at 5:57 a.m. <a title="UTC+08:00" href="https://en.wikipedia.org/wiki/UTC%2B08:00">local time</a> (21:57 UTC), which generated an <a title="Eruption column" href="https://en.wikipedia.org/wiki/Eruption_column">ash column</a> that rose to an altitude 500 meters into the sky. On 29 November, two days later, a major blast took place sending an ash column as high as 50000 ft (15.24 km) into the sky.<a title="Volcanic bomb" href="https://en.wikipedia.org/wiki/Volcanic_bomb">Volcanic bombs</a> have an impact radius of about 2 km from the main crater.

By Wednesday 2 December, it was reported that more than 5,500 people had been evacuated from their homes near the volcano. Residents on the slopes of Mt Ile Lewotolok had been warned of potential cold lava flows, especially during periods of heavy rain, and had been advised to remain outside of a 4-kilometer radius from the crater

Image Credit: NASA Earth Observatory 

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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

&nbsp;

Lewotolo volcano spews ash thousands of meters high

The collision of cargo vessels with whales is one of the leading causes of death for these majestic marine creatures. Despite high-profile accidents and localized research efforts, a comprehensive global picture of the risks posed by shipping to whales has remained elusive - until now.&nbsp;



A study led by the <a href="https://www.washington.edu/" target="_blank" rel="noreferrer noopener">University of Washington</a> (UW), with contributions from <a href="https://www.ucsb.edu/" target="_blank" rel="noreferrer noopener">University of California, Santa Barbara</a> (UCSB) researchers, reveals that global shipping routes overlap with 92% of the migratory ranges of blue, fin, humpback, and sperm <a href="https://www.earth.com/news/blue-whales-continue-their-battle-for-survival/" target="_blank" rel="noreferrer noopener">whales</a>.



<h2 class="wp-block-heading" id="h-global-risk-assessment-nbsp">Global risk assessment&nbsp;</h2>



Published in the journal <a href="http://dx.doi.org/10.1126/science.adp1950" target="_blank" rel="noreferrer noopener">Science</a>, the study offers the first global map of ship-strike risks for these four large whale species.&nbsp;



“Most <a href="https://www.earth.com/news/a-new-approach-to-protecting-whales-from-ship-strikes/" target="_blank" rel="noreferrer noopener">ship-strike</a> studies are done at a regional scale, which is critically important but doesn’t provide the full picture worldwide,” said co-author Rachel Rhodes, a project scientist at UCSB’s Benioff Ocean Science Laboratory.&nbsp;



“By taking this broader perspective, we can identify the highest-risk areas globally and strategically direct research and conservation efforts where they’re needed most.”



<div class="wp-block-sendtonews-playerselector">[sendtonews key="7sxoUzIVbl-4050404-12187" type="single"]</div>



<h2 class="wp-block-heading" id="h-whales-and-ships-a-deadly-intersection">Whales and ships: A deadly intersection</h2>



Cargo vessels, often the size of skyscrapers and over ten times the length of an adult blue whale, dominate the oceans. Any whale crossing their path faces almost certain death.&nbsp;



As shipping lanes increasingly intersect with whale migration routes, the likelihood of collisions grows.&nbsp;



According to Professor Briana Abrahms, this translates to ships traveling thousands of times the distance to the moon and back within these species’ ranges each and every year.&nbsp;



“And this problem is only projected to increase as global trade grows in the coming decades,” said Abrahms.



<h2 class="wp-block-heading" id="h-success-in-local-conservation-efforts">Success in local conservation efforts</h2>



While the outlook may seem grim, successful initiatives like <a href="https://whalesafe.com/" target="_blank" rel="noreferrer noopener">Whale Safe</a> off the California coast demonstrate the potential for mitigating these risks.&nbsp;



Whale Safe is a collaborative effort between researchers, citizen scientists, and shipping companies to reduce collisions by slowing vessels in whale-rich waters.&nbsp;



Tracking whale presence and providing data on ship compliance with slow zones have helped lower collision rates since the program’s launch in 2019.



“Getting the vessels to slow down works,” said UCSB marine ecologist and co-author Douglas McCauley, whose lab developed Whale Safe.&nbsp;



<h2 class="wp-block-heading" id="h-lack-of-adequate-protection-for-whales">Lack of adequate protection for whales</h2>



The Santa Barbara Channel, a vital migration corridor for blue, fin, and humpback whales, overlaps with major shipping hubs in Los Angeles, Long Beach, and Oakland.&nbsp;



Federal guidelines encourage ships to voluntarily reduce their speed from May to December to protect endangered whales.



Despite these localized successes, the study found that only 7% of the highest-risk areas globally have measures in place to protect whales from ship strikes.



<h2 class="wp-block-heading" id="h-mapping-whale-ship-collision-hotspots">Mapping whale-ship collision hotspots</h2>



To estimate collision risks, the researchers first needed to map whale habitats on an unprecedented global scale.&nbsp;



This involved compiling data from government surveys, public sightings, tagging studies, and even historic whaling vessel logbooks to track where blue, fin, humpback, and sperm whales live, feed, and migrate.&nbsp;



The team combined this information with the routes of 176,000 cargo vessels tracked between 2017 and 2022 using data from ships’ automatic identification systems and algorithms developed by <a href="https://globalfishingwatch.org/" target="_blank" rel="noreferrer noopener">Global Fishing Watch</a>.



<h2 class="wp-block-heading" id="h-identifying-high-risk-regions-nbsp">Identifying high-risk regions&nbsp;</h2>



The study revealed several new high-risk regions, including areas off southern Africa; the coasts of Brazil, Chile, Peru, and Ecuador in South America; the Azores; and East Asia, particularly near China, Japan, and South Korea.&nbsp;



“These are vast areas of the ocean where whales may quietly be being killed,” Rhodes said. “This may be a silent contributor to why we aren’t seeing more optimistic recoveries for some at-risk whale populations.”



The research also reaffirmed known hotspots, such as the Pacific coast of North America (including California), Panama, the Arabian Sea, Sri Lanka, the Canary Islands, and the Mediterranean Sea.



<h2 class="wp-block-heading" id="h-urgent-need-for-policy-changes">Urgent need for policy changes</h2>



The team discovered that mandatory measures to prevent whale-ship collisions are exceedingly rare, covering just 0.54% of blue whale hotspots, 0.27% of humpback hotspots, and none for fin or sperm whales.&nbsp;



Even marine protected areas often lack speed regulations for vessels, as they were initially established to address issues like overfishing and industrial pollution rather than shipping-related risks.



Encouragingly, 95% of the hotspots identified lie within nations’ exclusive economic zones (EEZs), meaning individual countries have the authority to implement protective measures.&nbsp;



“From the standpoint of <a href="https://www.earth.com/news/effective-conservation-efforts-key-to-saving-biodiversity/" target="_blank" rel="noreferrer noopener">conservation</a>, the fact that most high-risk areas lie within exclusive economic zones is actually encouraging,” said lead author Anna Nisi, a UW postdoctoral researcher.&nbsp;



“It means individual countries have the ability to protect the riskiest areas.”&nbsp;



Expanding protective measures to cover an additional 2.6% of the ocean’s surface would safeguard all the identified collision hotspots, the researchers estimate.



<h2 class="wp-block-heading" id="h-protecting-whales-from-ship-strikes-nbsp">Protecting whales from ship strikes&nbsp;</h2>



The experts hope their study will inspire local and regional research to refine hotspot maps, inform advocacy efforts, and address the impact of <a href="https://www.earth.com/news/how-a-warming-climate-will-change-the-humpback-whales-diet/" target="_blank" rel="noreferrer noopener">climate change</a>, which will alter whale and ship distributions as sea ice melts and ecosystems shift.



“Protecting whales from the impact of ship strikes is a huge global challenge,” said Jono Wilson, co-author and director of ocean science at <a href="https://www.nature.org/en-us/" target="_blank" rel="noreferrer noopener">The Nature Conservancy</a>ù’s California Chapter.&nbsp;



“We’ve seen the benefits of slowing ships down at local scales through programs like ‘Blue Whales Blue Skies’ in California. Scaling up such programs will require a concerted effort by conservation organizations, governments, and shipping companies.”



Whales play a critical role in <a href="https://www.earth.com/news/overfishing-and-habitat-degradation-have-devastated-marine-ecosystems/" target="_blank" rel="noreferrer noopener">marine ecosystems</a>, supporting biodiversity and contributing to ocean health. By identifying ship-collision hotspots and prioritizing these areas for conservation, this study offers a path forward to ensure their survival in an increasingly industrialized ocean.



Video Credit: Global Fishing Watch&nbsp;



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Ship routes overlap with 92% of whale habitats 

The collision of cargo vessels with whales is one of...

The Guitar Nebula is a fascinating cosmic object that was named for its uncanny resemblance to the instrument in glowing hydrogen light.



The <a href="https://www.earth.com/news/six-rogue-worlds-discovered-inside-a-young-star-forming-nebula/" target="_blank" rel="noreferrer noopener">cosmic</a> guitar isn't idle, though. It is constantly on the move, just as a swaying guitarist, belting out tune after tune.



The driving force behind its movement is the pulsar PSR B2224+65, a rapidly rotating neutron star. Picture it as the guitarist in this cosmic band.



And the music it plays? A flame-like filament of particles and X-rays. Over the years, astronomers have captured this symphony using NASA’s Chandra X-ray Observatory and Hubble Space Telescope.



<h2 class="wp-block-heading" id="h-secrets-of-the-guitar-nebula">Secrets of the Guitar Nebula</h2>



How does space manage to create such a bizarre <a href="https://www.earth.com/news/mysterious-signals-from-crab-nebula-form-a-zebra-pattern/" target="_blank" rel="noreferrer noopener">scenario</a>? 



The secret lies in the pulsar's fast rotation and strong magnetic fields. These extremes lead to particle acceleration and high-energy radiation, creating matter and antimatter pairs of electron and positron. 



In effect, the famous equation by Albert Einstein, E = mc2, which usually converts mass into energy, is reversed. In this case, energy converts into mass to produce the particles.



<h2 class="wp-block-heading" id="h-pulsar-s-journey-through-space">Pulsar’s journey through space</h2>



As the Guitar Nebula passes through space, it emanates a steady wind, like a gentle melody, causing particles to be ejected. 



These particles then create bubbles, and as the pulsar continues to traverse through a medium with variations in density, more bubbles are created behind it, forming our unique guitar shape.



This symphony isn’t a static tune. Images captured at different points indicate the changes this filament undergoes. It's a unique kind of cosmic rhythm.



<h2 class="wp-block-heading" id="h-observing-the-guitar-nebula">Observing the Guitar Nebula </h2>



The Chandra X-Ray Observatory and the Hubble Space Telescope have been instrumental in recording this intriguing performance.



A recent film, combining data from both, has revealed the pulsar and the filament moving towards the upper left - akin to a cosmic blow torch shooting from the tip of the guitar.



<div class="wp-block-sendtonews-playerselector">[sendtonews key="VzMYfwbr7c-4050286-12187" type="single"]</div>



<h2 class="wp-block-heading" id="h-significance-of-the-guitar-nebula">Significance of the Guitar Nebula</h2>



The Guitar <a href="https://www.earth.com/image/dark-wolf-nebula-in-the-constellation-scorpius/" target="_blank" rel="noreferrer noopener">Nebula</a> is more than just a captivating spectacle. The filament is helping astrologists understand how electrons and positrons traverse the interstellar medium. 



The nebula also serves as an example of how these particles get injected into the interstellar space.



None of the observations would be possible without the dedicated work of teams at the NASA’s <a href="https://www.nasa.gov/marshall/" target="_blank" rel="noreferrer noopener">Marshall Space Flight Center</a> and the <a href="https://www.cfa.harvard.edu/" target="_blank" rel="noreferrer noopener">Smithsonian Astrophysical Observatory</a>’s Chandra X-ray Center.



The experts manage and control the Chandra program's science operations and flight operations, respectively.



<h2 class="wp-block-heading" id="h-understanding-high-energy-astrophysics">Understanding high-energy astrophysics</h2>



The discovery and study of objects like the Guitar Nebula extend far beyond the realm of astronomy into the fundamental principles of physics.



By studying these celestial symphonies, astrophysicists are able to gather insights on the behavior of pulsars, their magnetic fields, and the dynamics of neutron stars. 



Such phenomena inform theories on how energy and matter interact at extreme scales, offering observable cases for complex physical equations. 



This knowledge contributes significantly to our understanding of high-energy astrophysics and the ongoing quest to unify the vast and diverse events occurring in the universe.



<h2 class="wp-block-heading" id="h-inspirations-for-science-and-art">Inspirations for science and art</h2>



Beyond contributing to scientific knowledge, the mesmerizing appearances and tales of cosmic structures inspire both amateur and professional artists. 



The Guitar Nebula's poetic dance through space, reminiscent of brushstrokes on a vast canvas or melodic chords in music, encourages creative interpretations and artistic expressions. 



This merging of science and art promotes a deeper public appreciation for cosmic phenomena, sparking curiosity and wonder about our universe.



Such inspiration ensures that the mysteries of space continue to captivate future generations, crossing the boundaries between disciplines and opening new avenues for interpretation and <a href="https://www.earth.com/image/cosmic-cannibalism-and-stellar-winds-unveiling-the-secrets-of-messier-76/" target="_blank" rel="noreferrer noopener">exploration</a>.



<h2 class="wp-block-heading" id="h-testament-to-the-wonders-of-space">Testament to the wonders of space</h2>



This cosmic concert, with the flamethrower guitar and its changing tune, is a testament to the wonders that space holds. 



What other cosmic secrets are out there, waiting to be unraveled? If a pulsar can play such a visually radiant tune, who knows what the other stars are up to?



So, the next time you gaze up at the night sky, remember the Guitar Nebula, belting out its symphony in the vast auditorium of space. 



Video &amp; Image Credit: Hubble/NASA/ESA/STScI and (Palomar) Hale Telescope/Palomar/CalTech



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The Guitar Nebula: A pulsar's dazzling performance in space

The Guitar Nebula is a fascinating cosmic object that was...

The Phlegraean Fields, now considered one massive supervolcano, are beginning to stir, making the scientific community uneasy. 



These volcanic fields, nestled just west of Naples, Italy, are among the top eight emitters of volcanic carbon dioxide worldwide. 



Since 2005, one spot in particular -- the Solfatara crater -- has been releasing increased volumes of gas, catching the attention of researchers and locals alike.



<h2 class="wp-block-heading" id="h-gas-emissions-at-solfatara-crater">Gas emissions at Solfatara crater</h2>



Gianmarco Buono, a volcanologist at the Italian National Institute of Geophysics and Volcanology (<a href="https://www.ingv.it/en/home" target="_blank" rel="noreferrer noopener">INGV</a>), is leading a study to understand what's behind this surge in gas emissions. 



"Estimating the source of the carbon dioxide is important to properly reconstruct what is happening in the magmatic system and the <a href="https://www.earth.com/news/knipovich-ridge-new-hydrothermal-field-arctic-intense-geological-activity/" target="_blank" rel="noreferrer noopener">hydrothermal system</a>," says Buono. 



His team aims to provide a tool that can distinguish between carbon dioxide coming from magma and that released by other processes, a method that could be useful in volcanic regions around the world.



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



In the simplest of terms, a supervolcano is essentially a volcano on steroids. It's a <a href="https://www.earth.com/news/how-early-humans-survived-the-eruption-of-toba-supervolcano/" target="_blank" rel="noreferrer noopener">massive volcanic system</a> capable of producing eruptions thousands of times more powerful than a regular volcano. 



These eruptions can eject more than 1,000 cubic kilometers of material into the atmosphere, which can have catastrophic effects on the global climate and environment.



You've probably heard of places like <a href="https://www.earth.com/news/yellowstone-tourism-generates-over-1-megaton-carbon-annually/" target="_blank" rel="noreferrer noopener">Yellowstone National Park</a> in the United States -- that's one of the most famous supervolcanoes. 



When a supervolcano erupts it can form a giant caldera, which is a huge crater that can span dozens of miles. 



The sheer scale of these eruptions makes them rare, but they're definitely something scientists keep an eye on due to their potential impact on <a href="https://www.earth.com/news/yellowstones-supervolcano-holds-a-surprising-amount-of-magma/" target="_blank" rel="noreferrer noopener">life across the planet</a>.



<h2 class="wp-block-heading" id="h-numbers-speak-volumes">Numbers speak volumes</h2>



Today, the Solfatara crater emits between 4,000 and 5,000 tons of carbon dioxide each day. To put that into perspective, that's equivalent to the emissions from burning about 500,000 gallons of gasoline daily. 



In their recent paper published in Geology, Buono and his colleagues estimate that 20% to 40% of this carbon dioxide comes from the dissolution of calcite in the surrounding rocks. The remaining 60% to 80% is traced back to <a href="https://www.earth.com/news/the-sun-affects-magma-formation-deep-within-the-earth/" target="_blank" rel="noreferrer noopener">underground magma</a>.



<h2 class="wp-block-heading" id="h-science-behind-the-solfatara-crater-gas">Science behind the Solfatara crater gas</h2>



When magma moves <a href="https://www.earth.com/news/volcanic-magma-traced-to-melting-in-earths-crust/" target="_blank" rel="noreferrer noopener">closer to the Earth's surface</a>, the pressure decreases, causing gases that were trapped inside to escape. These gases include water vapor, carbon dioxide, and sulfur dioxide. 



Scientists keep a close eye on volcanoes by monitoring earthquakes, measuring ground deformation, and analyzing gases emitted from fumaroles -- openings in the Earth's crust that release steam and gases.



An uptick in gas emissions can be a sign of potential volcanic activity. However, not every increase leads to an eruption. 



Sometimes, carbon dioxide is released when hot underground fluids interact with the rocks above, rather than from magma itself.



<h2 class="wp-block-heading" id="h-monitoring-changes-over-decades">Monitoring changes over decades</h2>



Since 1983, the Italian National Institute of Geophysics and Volcanology has been keeping tabs on the gas emissions from the Solfatara crater. 



By studying the ratios of nitrogen, helium, and carbon dioxide, researchers had initially concluded that the gases were primarily from <a href="https://www.earth.com/news/the-sun-affects-magma-formation-deep-within-the-earth/" target="_blank" rel="noreferrer noopener">deep magma sources</a>. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/11/Phlegraean-fields_supervolcano_caldera_satellite-view_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/11/Phlegraean-fields_supervolcano_caldera_satellite-view_1s.webp" alt="Satellite view of Phlegraean Fields and Solfatara crater showing a large caldera supervolcano west of Naples, Italy. It is part of the Campanian volcanic arc, which includes Mount Vesuvius." class="wp-image-1951186"/></a><figcaption class="wp-element-caption">Satellite view of Phlegraean Fields and Solfatara crater showing a large caldera supervolcano west of Naples, Italy. It is part of the Campanian volcanic arc, which includes Mount Vesuvius.</figcaption></figure>



"We focused mainly on geochemical variation, especially for carbon dioxide, helium, and nitrogen, because they are non-reactive species. They contain information about what is happening in the magma," Buono explains.



But things started to change in 2005. The data began to deviate from the typical chemical signatures of magma-derived gases. This shift continued over time, accompanied by rising temperatures in the shallow hydrothermal system. 



By 2012, the alert level for the region was raised from green to yellow, signaling heightened activity but not an immediate threat of eruption.



<h2 class="wp-block-heading" id="h-clues-from-the-earth-s-movements">Clues from the Earth's movements</h2>



The area didn't just experience changes underground. Small earthquakes and noticeable ground deformation were also observed. 



These signs pointed toward the circulation of hot fluids <a href="https://www.earth.com/news/new-research-enhances-predictions-on-volcanic-eruptions/" target="_blank" rel="noreferrer noopener">beneath the surface</a>. When these hot, acidic fluids interact with calcite in the rocks, they can release additional carbon dioxide.



Previous studies involving drill cores of the local rocks revealed that the calcite present has a composition similar to the gases being emitted. 



Based on this information, Buono's team estimated that 20% to 40% of the carbon dioxide at the Solfatara crater comes from the breakdown of calcite in the host rocks.



The Phlegraean Fields have a long volcanic history, with activity dating back approximately 40,000 years. The most recent eruption occurred in 1538. 



Since the 1950s, the region has experienced several phases of unrest, reminding us that <a href="https://www.earth.com/news/volcanic-super-eruptions-build-up-for-millions-of-years/" target="_blank" rel="noreferrer noopener">Earth's geology is always in motion</a>.



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



Understanding the source of carbon dioxide emissions in volcanic regions is crucial for public safety and environmental monitoring. 



By distinguishing between gases released from magma and those from other processes, scientists can better predict <a href="https://www.earth.com/news/underwater-volcanic-eruptions-are-more-harmful-than-previously-believed/" target="_blank" rel="noreferrer noopener">volcanic activity</a> and assess potential risks.



Buono's research not only sheds light on the complex interactions beneath the Phlegraean Fields but also provides tools that could be applied to other volcanic areas. 



As he notes, "Our aim is to provide a tool to better discriminate the contribution of magmatic and non-magmatic carbon dioxide that can also be applied to other systems."



<h2 class="wp-block-heading" id="h-solfatara-crater-and-the-future">Solfatara crater and the future</h2>



To sum it all up, figuring out what's really going on beneath the Phlegraean Fields and Solfatara crater is a big deal -- not just for the science buffs but for everyone living on Earth.



Buono's team has shown that the spike in carbon dioxide emissions isn't just magma pushing its way up. A good chunk of that gas is actually coming from hot fluids interacting with calcite-rich rocks underground. 



This kind of info is gold because it helps us keep a closer eye on volcanic activity and, more importantly, keeps people safe.



Looking ahead, keeping tabs on these emissions and understanding their sources is key. By knowing whether the carbon dioxide is from magma or from rock interactions, scientists can better predict what's coming next. 



The Phlegraean Fields are a vivid reminder that our planet is always on the move. Scientists like Buono will keep unraveling the mysteries beneath our feet, helping us understand the dynamic planet we call home.



The full study was published in the journal <a href="https://pubs.geoscienceworld.org/gsa/geology/article/51/4/397/620796/Discriminating-carbon-dioxide-sources-during" target="_blank" rel="noreferrer noopener">Geology</a>.



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Supervolcano shows signs of waking up, which would plunge the world into chaos

The Phlegraean Fields, now considered one massive supervolcano, are beginning...

Many of the world's glaciers formed during the last glacial maximum. These glaciers, remnants of the Ice Age, have persisted for thousands of years in high-altitude or polar regions.



However, there are big changes ahead. A recent study reveals that over half of the world's glaciers could disappear by the end of this century.



The research, conducted by scientists at <a href="https://ethz.ch/en.html" target="_blank" rel="noreferrer noopener">ETH Zurich</a> in Switzerland and <a href="https://www.vub.be/nl" target="_blank" rel="noreferrer noopener">Vrije Universiteit Brussel</a> in Belgium, suggests a chilling forecast for our planet's glaciers.



The scientists estimated potential <a href="https://www.earth.com/news/glacier-melt-in-alaska-is-accelerating-at-an-alarming-rate/" target="_blank" rel="noreferrer noopener">glacier loss</a> under various carbon emissions scenarios. They took into account all of our planet's glaciers - a whopping 200,000 in total.



<h2 class="wp-block-heading" id="h-glaciers-under-severe-threat">Glaciers under severe threat</h2>



The numbers from the study are daunting. Under a high emissions scenario, up to 54 percent of all glaciers could vanish. In the Alps, this number reaches an alarming 75 percent.



"Glaciers are crucial in many parts of the world, and as such, glacier changes directly impact our society and the natural environment," said study lead author and glaciologist Professor Harry Zekollari.



"Locally, glaciers can lead to natural hazards, they have an important touristic value, and they determine local water supply."



<h2 class="wp-block-heading" id="h-from-melting-glaciers-to-rising-sea-levels">From melting glaciers to rising sea levels</h2>



The melting of glaciers does not stop at the loss of an icy spectacle; the repercussions are far-reaching. One of the biggest concerns is the contribution of melting glaciers to <a href="https://www.earth.com/news/rising-sea-levels-threaten-groundwater-global-cities-underground-infrastructure/" target="_blank" rel="noreferrer noopener">rising sea levels</a>, which heighten the risk of floods in coastal towns and cities.



Moreover, glacier loss diminishes <a href="https://www.earth.com/news/satellites-reveal-a-sudden-drop-in-global-freshwater-levels/" target="_blank" rel="noreferrer noopener">freshwater</a> resources that millions of people depend on for drinking water.



"Water supply from glaciers (and how this supply changes) will impact biodiversity and water availability for industry, agriculture, and households," said Professor Zekollari.



The greenhouse effect only serves to worsen the crisis. As the Earth's <a href="https://www.earth.com/news/could-tree-planting-warm-earth-science-behind-albedo-effect/" target="_blank" rel="noreferrer noopener">albedo</a> - the ability to reflect sunlight - decreases, more energy from the sun is absorbed rather than reflected. This raises the risk of global warming, further aggravating climate change.



<h2 class="wp-block-heading" id="h-predicting-glacier-mass-loss">Predicting glacier mass loss</h2>



To estimate future glacier loss, the research team studied historical glacier masses, carbon emissions, and temperature data. 



Armed with this information and the aid of computer modeling, the experts were able to make predictions about future glacier mass loss.



"By modeling glacier evolution throughout the 21st century under various climate scenarios, we found stark differences in outcomes depending on future emission levels," noted Professor Zekollari.



Under low carbon emissions, glaciers could lose 25 to 29 percent of their mass by 2100. Under a high-emissions scenario, that figure could rise to between 46 and 54 percent.



The European Alps' glaciers are among the most vulnerable. These glaciers are predicted to lose more than 75 percent of their volume under high-emission scenarios.



However, <a href="https://www.earth.com/news/earth-polar-regions-changing-fundamental-alarming-ways/" target="_blank" rel="noreferrer noopener">polar regions</a> like Arctic Canada, Iceland, and Svalbard might retain a larger part of their glacier mass by century-end, albeit still facing significant loss.



<h2 class="wp-block-heading" id="h-uncertainties-in-glacier-evolution">Uncertainties in glacier evolution</h2>



Despite these painful revelations, the team acknowledges uncertainties in the projected glacier evolution, while stressing that the research specifically examined glaciers, not ice sheets.



Ice sheets, the gargantuan masses of glacial ice found on Greenland and Antarctica, carry about 99 percent of Earth's freshwater.



While these ice sheets hold greater mass and react on longer timescales, their contribution to sea-level rise is about the same (or even slightly less) than from the 200,000 glaciers under study.



"For us it is indeed the crucial that all numbers by us and other researchers are combined to get the full sea-level rise picture," concluded Professor Zekollari.



The fragility of our world's glaciers highlights the pressing need for proactive climate action. 



<h2 class="wp-block-heading" id="h-preserving-glaciers-a-collective-responsibility">Preserving glaciers: A collective responsibility</h2>



The fate of the world's glaciers is not set in stone. By reducing carbon emissions and implementing sustainable environmental policies, it is possible to slow their decline. 



Efforts like transitioning to renewable energy, protecting vulnerable ecosystems, and raising global awareness about the importance of glaciers can help mitigate their loss. 



Every action we take today helps protect glaciers for future generations, ensuring the preservation of freshwater resources, biodiversity, and the delicate balance of our climate.



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Over half of the world’s glaciers are on pace to disappear by 2100

Many of the world's glaciers formed during the last glacial...

A galaxy racing through space at an astonishing speed of two million mph (3.2 million km/h) has created a dramatic collision, observed in unprecedented detail by one of Earth’s most advanced telescopes.&nbsp;



The event occurred in <a href="https://www.earth.com/image/stephans-quintet-in-unprecedented-detail/" target="_blank" rel="noreferrer noopener">Stephan’s Quintet</a>, a well-known group of five interacting galaxies first discovered nearly 150 years ago. 



The collision unleashed a powerful shockwave described as being akin to a “sonic boom from a jet fighter,” showcasing one of the Universe's most striking phenomena.



The galaxy responsible, NGC 7318b, passed through Stephan’s Quintet, triggering the reactivation of a chaotic field of debris left behind by previous <a href="https://www.earth.com/news/galaxy-collisions-hubble-spots-a-string-of-pearls-star-cluster/" target="_blank" rel="noreferrer noopener">galactic collisions</a>.&nbsp;



This rare event was captured by the William Herschel Telescope Enhanced Area Velocity Explorer (WEAVE), a state-of-the-art spectrograph located in La Palma, Spain.



<h2 class="wp-block-heading" id="h-stephan-s-quintet-a-galactic-crossroad">Stephan’s Quintet: A galactic crossroad</h2>



“Since its discovery in 1877, Stephan’s Quintet has captivated astronomers because it represents a galactic crossroad where past collisions between galaxies have left behind a complex field of debris,” explained lead author Marina Arnaudova, an astronomer at the <a href="https://www.herts.ac.uk/" target="_blank" rel="noreferrer noopener">University of Hertfordshire</a>.&nbsp;



“Dynamical activity in this galaxy group has now been reawakened by a galaxy smashing through it at an incredible speed of over two million mph, leading to an immensely powerful shock, much like a sonic boom from a jet fighter.”



This new insight into Stephan’s Quintet was achieved using WEAVE’s Large Integral Field Unit (LIFU), part of a €20-million (£16.7-million) next-generation science facility.&nbsp;



WEAVE’s capabilities allow astronomers to explore the composition and behavior of stars and gasses within galaxies, offering unprecedented detail about the dynamics of galactic interactions.



<h2 class="wp-block-heading" id="h-the-dual-nature-of-the-shockwave">The dual nature of the shockwave</h2>



One of the study’s most significant findings was the dual nature of the shockwave produced by the collision.&nbsp;



“As the shock moves through pockets of cold gas, it travels at hypersonic speeds - several times the speed of sound in the intergalactic medium of Stephan’s Quintet - powerful enough to rip apart electrons from atoms, leaving behind a glowing trail of charged gas, as seen with WEAVE,” Arnaudova said.



However, the shock behaves differently when it interacts with surrounding hot gas.&nbsp;



“Instead of causing significant disruption, the weak shock compresses the hot gas, resulting in <a href="https://www.earth.com/news/earths-radio-waves-recorded-from-the-moon-for-the-first-time/" target="_blank" rel="noreferrer noopener">radio waves</a> that are picked up by radio telescopes like the Low Frequency Array (LOFAR),” explained Soumyadeep Das, a PhD student at the University of Hertfordshire.



<h2 class="wp-block-heading" id="h-advanced-instruments-unlock-new-insights">Advanced instruments unlock new insights</h2>



The detailed observations combined data from WEAVE with those from other cutting-edge instruments, including LOFAR, the Very Large Array (VLA), and the James Webb Space Telescope (JWST). 



WEAVE, which is attached to the William Herschel Telescope, analyzes light from stars and gas through spectroscopy. 



<figure class="wp-block-image aligncenter size-full is-resized"><a href="https://www.earth.com/wp-content/uploads/2024/11/galaxy-collision_Stephans-Quintet_2-million-mph_UHertfordshire_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/11/galaxy-collision_Stephans-Quintet_2-million-mph_UHertfordshire_1s.webp" alt="WEAVE data overlaid on a James Webb Space Telescope image of Stephan's Quintet, with green contours showing radio data from the Low Frequency Array (LOFAR) radio telescope. The orange and blue colors follow the brightness of Hydrogen-alpha obtained with the WEAVE LIFU, which trace where the intergalactic gas is ionized. Credit: University of Hertfordshire" class="wp-image-1951174" style="width:300px;height:auto"/></a><figcaption class="wp-element-caption">WEAVE data overlaid on a James Webb Space Telescope image of Stephan's Quintet, with green contours showing radio data from the Low Frequency Array (LOFAR) radio telescope. The orange and blue colors follow the brightness of Hydrogen-alpha obtained with the WEAVE LIFU, which trace where the intergalactic gas is ionized. Credit: University of Hertfordshire</figcaption></figure>



This process reveals a “bar code” of colors that uncovers the elements present in <a href="https://www.earth.com/news/white-dwarf-stars-may-be-billions-of-years-older-than-estimated/" target="_blank" rel="noreferrer noopener">stars</a>, providing crucial information about galactic composition and behavior.



This advanced spectrograph was developed through an international partnership involving France, Italy, Spain, the Netherlands, and the UK. 



Its primary mission is to provide groundbreaking insights into the formation of the Milky Way and other galaxies, as well as the evolution of the Universe.



<h2 class="wp-block-heading" id="h-a-glimpse-into-galactic-evolution">A glimpse into galactic evolution</h2>



Stephan’s Quintet offers a unique laboratory for understanding the violent interactions between galaxies.&nbsp;



Professor Gavin Dalton is the WEAVE principal investigator at RAL Space and the University of Oxford.



“The shock and the unfolding collision that we see in Stephan’s Quintet provide a remarkable perspective on what may be happening in the formation and evolution of the barely resolved faint galaxies that we see at the limits of our current capabilities,” said Dalton.&nbsp;



“It’s really neat work that Marina has put together with this large team, but this first WEAVE science paper also represents just a taste of what is to come over the next five years now that WEAVE is becoming fully operational,” added Daniel Smith of the University of Hertfordshire.



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



The findings mark an exciting beginning for WEAVE’s role in astronomy.&nbsp;



“I’m excited to see that the data gathered at the WEAVE first light already provide a high-impact result, and I’m sure this is just an early example of the types of discoveries that will be made possible with WEAVE on the William Herschel Telescope in the coming years,” said Marc Balcells, director of the Isaac Newton Group of Telescopes.



By capturing the details of this dramatic galactic collision, WEAVE has demonstrated its potential to revolutionize our understanding of the cosmos.&nbsp;



With its ability to analyze light from stars and gasses with unprecedented speed and accuracy, the spectrograph is set to uncover more insights into <a href="https://www.earth.com/news/early-galaxy-formation-occurred-much-faster-than-we-thought/" target="_blank" rel="noreferrer noopener">galaxy formation</a>, evolution, and the chaotic interactions shaping the Universe.



Image Credit: University of Hertfordshire



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Galaxies colliding at 2 million miles per hour observed in unprecedented detail

A galaxy racing through space at an astonishing speed of...

Scientists have been scratching their heads about the purpose of the ultrasonic vocalizations (USVs) made by rodents since these sounds were first discovered in the 1950s.



A widely accepted theory suggests a role in social communication, and paints a picture of rodents using these sounds to attract mates.



<h2 class="wp-block-heading" id="h-rodents-and-ultrasonic-vocalizations">Rodents and ultrasonic vocalizations</h2>



Dr. Eduardo Mercado III, a professor of psychology at the University of Buffalo <a href="https://arts-sciences.buffalo.edu" target="_blank" rel="noreferrer noopener">College of Arts and Sciences</a>, proposes a fresh perspective on rodents' USVs. 



According to Dr. Mercado, when rodents make these <a href="https://www.earth.com/news/ultrasound-waves-can-enhance-mindfulness-and-brain-health/" target="_blank" rel="noreferrer noopener">sounds</a>, the aim isn't romance, but something else entirely. 



"This phenomenon has never been observed before, or I believe even suspected, in any animal," said Dr. Mercado. 



"They're creating new pathways of information by manipulating their environment and controlling the molecular interactions of particles around them."



This radical idea could carry broad implications, possibly leading to innovative treatments for psychological disorders and advancements in technology.



One might even imagine these clever rodents as having Jedi skills, as Mercado humorously suggests. It is almost as if they practice a form of "magic," manipulating their environment to their advantage.



<h2 class="wp-block-heading" id="h-a-discovery-inspired-by-whale-songs">A discovery inspired by whale songs</h2>



Dr. Mercado's background in the study of humpback whale songs led to his revolutionary hypothesis.



While attending a meeting on ultrasonic vocalizations, he recognized certain inconsistencies in rodent behavior that didn't quite align with the prevalent thought on the purpose of USVs.



Rodents explore their environment using their whiskers, visual scans, and incessant sniffing. 



Interestingly, Dr. Mercado found that studies which monitored sniffing alongside vocalizations showed that rodents would immediately sniff the air after producing each USV.



Could it be that these two actions are interconnected?



<h2 class="wp-block-heading" id="h-how-rats-might-use-ultrasonic-sounds">How rats might use ultrasonic sounds</h2>



Vibroacoustics, a field concerned with <a href="https://www.earth.com/news/zapping-the-brain-with-ultrasound-waves-may-cure-drug-addiction/" target="_blank" rel="noreferrer noopener">ultrasonic</a> vibrations, uses sound to manipulate particle clusters.



Drawing parallels, Dr. Mercado suggests that rodents might be using their ultrasonic vocalizations to create odor clusters in the air, thereby enhancing their ability to detect airborne chemicals, such as pheromones.



"That could be a coincidence, or it might suggest the two are functionally related," said Dr. Mercado. 



"I knew that techniques for using ultrasound to manipulate particles are used in the field of vibroacoustics and thought immediately that might also work for animals."



In rodents, this manipulation would make it easier for individuals to detect and identify others within their social sphere - distinguishing friends from strangers and competitors with better precision.



This implies that by vocalizing through ultrasonic sounds, rats are helping themselves to smell odors in their environment.



<h2 class="wp-block-heading" id="h-implications-for-human-health">Implications for human health</h2>



Rodent vocalizations have helped in the study of human disorders related to <a href="https://www.earth.com/news/how-ermine-moths-effortlessly-produce-ultrasonic-warning-sounds/" target="_blank" rel="noreferrer noopener">communication</a>, emotional processing, and social behavior.



The understanding of conditions such as anxiety, depression, schizophrenia, Parkinson's disease, and autism has advanced due to the results from studies of rodent vocalizations.



"Rodents are at the forefront of biological research," said study co-author Jessica Zhou, a student researcher at <a href="https://www.harvard.edu" target="_blank" rel="noreferrer noopener">Harvard University</a>. "Rodents, especially rats and mice, are the unsung heroes of the scientific world."



Their contributions to biological research could widen if this intriguing hypothesis holds true.



<h2 class="wp-block-heading" id="h-evolution-of-complex-cognitive-processes">Evolution of complex cognitive processes </h2>



An interesting evolutionary perspective illustrates how the sense of smell, used for exploration, has driven the evolution of more complex cognitive processes, including attention and memory. 



A deeper understanding of this system might provide insights into the evolution of these crucial cognitive functions.



While the potential uses of rodent <a href="https://www.earth.com/news/ultrasound-helps-save-sea-turtles-from-fishing-nets/" target="_blank" rel="noreferrer noopener">USVs</a> in scientific research is significant, several challenges must be addressed to harness their benefits fully.



Rigorous experimental designs are necessary to test Dr. Mercado’s hypothesis empirically across various rodent species and environmental conditions.



Moreover, advancements in acoustic technology could enhance our ability to capture and analyze these ultrasonic frequencies with greater precision. 



<h2 class="wp-block-heading" id="h-rats-sounds-and-new-innovations">Rats, sounds, and new innovations</h2>



The journey ahead requires an open mind and a commitment to innovation. 



The next few years could prove pivotal in confirming whether rodents truly manipulate their chemical environments or if another unknown factor is at play.



Understanding this process could inform the development of new technologies. 



Drawing a parallel to how understanding vision in nocturnal animals led to the development of night-vision goggles, the authors propose that recognizing the reasons for rodents' intriguing use of sound might pave the way for sonic-manipulation technologies involving nanoparticles.



The study is published in the journal <a href="https://www.sciencedirect.com/science/article/abs/pii/S0149763424003774?via%3Dihub" target="_blank" rel="noreferrer noopener">Neuroscience &amp; Biobehavioral Reviews.</a>



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Rats have a "magical" ability to move matter using soundwaves

Scientists have been scratching their heads about the purpose of...

History is filled with mysterious artifacts, and the Aztec death whistle is an intriguing example.



Imagine a musical instrument with the sound of a terrifying, blood-curdling scream. This unusual whistle had a place in the fascinating world of the Aztec civilization during the pre-Columbian era in Mesoamerica.



This rich cultural context presents a labyrinth of mythology that is steeped in fearsome deities and chilling rituals – many of which may have employed this eerie instrument to good effect.



The death whistle's skull-shaped design is believed to symbolize Mictlantecuhtli, the fearsome Lord of the Aztec Underworld. 



The instrument's chilling sound may have served as a sorrowful fanfare preceding human sacrifices, at a time when the victims were being prepared for their mythical descent into Mictlan, the gloomy realm of the afterlife.



<h2 class="wp-block-heading" id="h-unique-mechanics-of-the-aztec-death-whistle">Unique mechanics of the Aztec death whistle</h2>



Of course, such startling audial experiences pique the curiosity of scientists. 



So it's no surprise that a team of researchers ventured into the history-laden world of <a href="https://www.earth.com/news/aztecs-kept-accurate-time-using-the-sun-and-the-mountains/" target="_blank" rel="noreferrer noopener">Aztec</a> musical instruments, keen to unravel the secrets of the death whistle's unique sonic properties. 



The research was conducted at the <a href="https://www.uzh.ch/en.html" target="_blank" rel="noreferrer noopener">University of Zurich</a>, and was led by Sascha Frühholz, professor of cognitive and affective neuroscience.



The researchers embarked on their exploration using 3D digital reconstructions of original Aztec death whistles, sourced from the Ethnological Museum in Berlin.



What they discovered was a wholly peculiar internal construction that featured two opposing sound chambers able to create physical air turbulence as the source of the screeching sound.



“The whistles have a very unique construction, and we don’t know of any comparable musical instrument from other pre-Columbian cultures or from other historical and contemporary context,” noted Frühholz.



<h2 class="wp-block-heading" id="h-the-emotive-impact-of-the-death-whistle">The emotive impact of the death whistle</h2>



Undeniably, the chilling whistle of <a href="https://www.earth.com/news/third-state-of-existence-beyond-life-and-death-confirmed-by-scientists/" target="_blank" rel="noreferrer noopener">death</a> is one of a kind. But what makes it so terrifying? 



To answer this, the Swiss research team gathered sound recordings of people blowing original Aztec death whistles, and compared them to those blowing handmade replicas.



When played back, listeners described the sounds as extremely chilling and frightening.



<div class="wp-block-sendtonews-playerselector">[sendtonews key="LrUGbnrmsd-4049652-12187" type="single"]</div>



According to the research analysis, the Aztec death whistle seems to mimic other deterring and fearsome sounds, both acoustically and affectively.



Intriguingly, human listeners perceived the whistle's sound to be partly organic and natural, like a human voice or scream. 



“This is consistent with the tradition of many <a href="https://www.earth.com/news/humans-started-cumulative-culture-around-600000-years-ago/" target="_blank" rel="noreferrer noopener">ancient cultures</a> to capture natural sounds in musical instruments, and could explain the ritual dimension of the death whistle sound for mimicking mythological entities,” said Frühholz.



<h2 class="wp-block-heading" id="h-psychological-responses-to-the-death-whistle">Psychological responses to the death whistle</h2>



Digging deeper into the human reaction to the mysterious instrument, brain recordings were made while listeners were exposed to the whistle's sounds.



The results showed significant response in the regions belonging to the affective neural system, highlighting the eerie and sinister nature of the sound.



Moreover, the team observed brain activity in regions that associate sounds with symbolic meaning, suggesting that the death whistle combines both affective influence and complex mental processes of sound symbolism.



<h2 class="wp-block-heading" id="h-linking-modern-minds-to-ancient-aztec-audiences">Linking modern minds to ancient Aztec audiences</h2>



The power of music to stir emotions has been recognized across cultures and eras. 



Similarly, the Aztec communities may have utilized the death whistle's symbolic and unnerving properties during their <a href="https://www.earth.com/news/stone-age-humans-from-magdalenian-culture-practiced-cannibalism-as-part-of-funeral-rituals/" target="_blank" rel="noreferrer noopener">ritual</a> ceremonies. 



They may have capitalized on the fear and awe inspired by the whistle to sway the audience's emotional state.



“Unfortunately, we could not perform our psychological and neuroscientific experiments with humans from ancient Aztec cultures. But the basic mechanisms of affective response to scary sounds are common to humans from all historical contexts,” said Frühholz.



<h2 class="wp-block-heading" id="h-using-sounds-to-evoke-emotions">Using sounds to evoke emotions</h2>



The Aztec death whistle offers a fascinating glimpse into how ancient cultures harnessed sound to evoke emotions and communicate profound ideas. Its chilling resonance reminds us of the universal power of sound to influence human psychology.



Modern studies on the death whistle's acoustic properties highlight its ability to mimic organic sounds, such as screams, which are universally recognized as distress signals.



This unique feature has opened doors for contemporary researchers to explore parallels between ancient instruments and the science of <a href="https://www.earth.com/news/sounds-can-change-the-way-we-see-things/" target="_blank" rel="noreferrer noopener">sound perception</a>. 



For instance, understanding how the whistle triggers fear and awe in listeners provides insight into how humans react to auditory cues in both natural and artificial environments. 



These findings have applications in fields ranging from neuroscience to sound design, demonstrating the enduring relevance of this ancient artifact.



The Aztec death whistle’s haunting legacy not only sheds light on the creativity of the Aztec civilization but also challenges us to consider the cultural significance of sound in shaping human experience across history.



The study is published in the journal <a href="https://www.nature.com/articles/s44271-024-00157-7" target="_blank" rel="noreferrer noopener">Communications Psychology</a>.



Image Credit: Sascha Frühholz



Video Credit: University of Zurich 



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Secrets of the Aztec death whistle's terrifying sound

History is filled with mysterious artifacts, and the Aztec death...

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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

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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...

Brutal fire season continues in California. Today&#8217;s Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> shows late-autumn fires burning southeast of Los Angeles. Large burn scars from earlier this year are also visible in the photograph.
California&#8217;s fire season typically ends in October, but global warming has increased the risk for fires in the fall season.
Despite the previous fires, enough brush and vegetation remains to fuel the new fires. According to NASA, strong Santa Ana winds with gusts measuring between 70 and 95 miles per hour on December 2nd and 3rd helped push the flames into new areas of dry vegetation. Brutal fire season continues in California
While the winds have since died down, there is an urgency to contain the fires before strong winds pick back up next week. 
Since the beginning of 2020, fires have burned more than 1.4 million acres in California. 
The image was captured on December 3, 2020, with the Operational Land Imager (OLI) on the Landsat 8 satellite. California is also <a title="List of country subdivisions by population" href="https://en.wikipedia.org/wiki/List_of_country_subdivisions_by_population">the most populated subnational entity</a> in North America, and has its state capital in <a title="Sacramento, California" href="https://en.wikipedia.org/wiki/Sacramento,_California">Sacramento</a>. The <a title="Greater Los Angeles" href="https://en.wikipedia.org/wiki/Greater_Los_Angeles">Greater Los Angeles</a> area and the <a title="San Francisco Bay Area" href="https://en.wikipedia.org/wiki/San_Francisco_Bay_Area">San Francisco Bay Area</a> are the nation&#8217;s second- and fifth-most-populous <a title="Statistical area (United States)" href="https://en.wikipedia.org/wiki/Statistical_area_(United_States)">urban regions</a>, with more than 18.7 million and 9.6 million residents respectively.<a href="https://en.wikipedia.org/wiki/California#cite_note-13">[13]</a> <a title="Los Angeles" href="https://en.wikipedia.org/wiki/Los_Angeles">Los Angeles</a> is California&#8217;s <a title="List of largest California cities by population" href="https://en.wikipedia.org/wiki/List_of_largest_California_cities_by_population">most populous city</a>, and the country&#8217;s <a title="List of United States cities by population" href="https://en.wikipedia.org/wiki/List_of_United_States_cities_by_population">second-most-populous</a>, after <a title="New York City" href="https://en.wikipedia.org/wiki/New_York_City">New York City</a>. California also has the nation&#8217;s <a title="List of the most populous counties in the United States" href="https://en.wikipedia.org/wiki/List_of_the_most_populous_counties_in_the_United_States">most populous county</a>, <a title="Los Angeles County, California" href="https://en.wikipedia.org/wiki/Los_Angeles_County,_California">Los Angeles County</a>, and its <a title="List of the largest counties in the United States by area" href="https://en.wikipedia.org/wiki/List_of_the_largest_counties_in_the_United_States_by_area">largest county</a> by area, <a title="San Bernardino County, California" href="https://en.wikipedia.org/wiki/San_Bernardino_County,_California">San Bernardino County</a>. The <a title="San Francisco" href="https://en.wikipedia.org/wiki/San_Francisco">City and County of San Francisco</a> is both the country&#8217;s <a title="List of United States cities by population density" href="https://en.wikipedia.org/wiki/List_of_United_States_cities_by_population_density">second most densely populated major city</a> after New York City and the <a title="County statistics of the United States" href="https://en.wikipedia.org/wiki/County_statistics_of_the_United_States">fifth-most-densely populated county</a>, behind only four of the five New York City <a title="Boroughs of New York City" href="https://en.wikipedia.org/wiki/Boroughs_of_New_York_City">boroughs</a>.
Image Credit: NASA Earth Observatory 
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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

Brutal fire season continues in California

Two very different sides of the Himalayas. Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> shows the remarkable contrast between the sparsely populated Tibetan Plateau and the densely populated North Indian River Plain. 

The brightly lit network of cities south of the Himalayas includes New Delhi, India, and Lahore, Pakistan. Enriched by the Indus and the Ganges rivers, this agriculturally fertile area is one of the most densely populated regions on Earth. It is currently home to more than 400 million people. Two very different sides of the Himalayas. 

The Tibetan Plateau, also known as the "Roof of the World," is located 14,764 feet above sea level on the other side of the Himalayas. The high altitude conditions are not conducive to extensive human settlement, and the Indigenous people who live on the Tibetan Plateau are acclimated to the harsh climate. 

Lifted by the <a title="Subduction" href="https://en.wikipedia.org/wiki/Subduction">subduction</a> of the <a title="Indian Plate" href="https://en.wikipedia.org/wiki/Indian_Plate">Indian tectonic plate</a> under the <a title="Eurasian Plate" href="https://en.wikipedia.org/wiki/Eurasian_Plate">Eurasian Plate</a>, the Himalayan mountain range runs west-northwest to east-southeast in an arc 2,400 km (1,500 mi) long. Its western anchor, <a title="Nanga Parbat" href="https://en.wikipedia.org/wiki/Nanga_Parbat">Nanga Parbat</a>, lies just south of the northernmost bend of the Indus river. Its eastern anchor, <a title="Namcha Barwa" href="https://en.wikipedia.org/wiki/Namcha_Barwa">Namcha Barwa</a>, is just west of the great bend of the <a class="mw-redirect" title="Yarlung Tsangpo River" href="https://en.wikipedia.org/wiki/Yarlung_Tsangpo_River">Yarlung Tsangpo River</a> (upper stream of the <a title="Brahmaputra River" href="https://en.wikipedia.org/wiki/Brahmaputra_River">Brahmaputra River</a>). The Himalayan range is bordered on the northwest by the <a title="Karakoram" href="https://en.wikipedia.org/wiki/Karakoram">Karakoram</a> and the <a title="Hindu Kush" href="https://en.wikipedia.org/wiki/Hindu_Kush">Hindu Kush</a> ranges.

Image Credit: NASA Earth Observatory 

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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