Today's Image of the Day from the European Space Agency features a brilliant stellar nursery located about 163,000 light-years away.



According to ESA, the image is one of the most photogenic examples of the many stellar nurseries observed by the NASA/ESA Hubble Space Telescope during its 30-year lifetime. 



“The portrait features the giant nebula NGC 2014 and its neighbor NGC 2020 which together form part of a vast star-forming region in the Large Magellanic Cloud, a satellite galaxy of the Milky Way,” noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



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



Stellar nurseries are regions in space where new stars are <a href="https://www.earth.com/news/baby-stars-release-sneezes-of-gas-and-dust-as-they-develop/" target="_blank" rel="noreferrer noopener">born</a> - often within vast clouds of gas and dust called molecular clouds.&nbsp;



These areas are fascinating because they are cradles of stellar evolution, where gravity causes clumps of gas to collapse, eventually forming protostars.&nbsp;



Over time, the protostars will heat up and start the nuclear fusion process that powers a star.



One of the most well-known stellar nurseries is the Orion Nebula, which is visible to the naked eye and located about 1,350 light-years from Earth.&nbsp;



<h2 class="wp-block-heading" id="h-dynamic-nature-of-a-stellar-nursery-nbsp">Dynamic nature of a stellar nursery&nbsp;</h2>



Within these nurseries, the balance between gravity and pressure determines the types of stars that form, from massive, luminous stars to smaller, cooler ones like our Sun.&nbsp;



The environment is incredibly dynamic, with powerful winds from young stars shaping the clouds and triggering the birth of even more stars.



These regions are often illuminated by the light from massive newborn stars - creating stunning, colorful displays. The light reveals the intricate structure of the dust and gas, sculpted by the energy of young stars.&nbsp;



<h2 class="wp-block-heading" id="h-significance-of-stellar-nurseries-nbsp">Significance of stellar nurseries&nbsp;</h2>



Stellar nurseries are essential for understanding the early stages of planetary formation, as protoplanetary disks (the material from which <a href="https://www.earth.com/news/planet-formation-new-insights-mechanics-physics/" target="_blank" rel="noreferrer noopener">planets form</a>) are often found around young stars in these regions.



Stellar nurseries play a crucial role in the ongoing evolution of <a href="https://www.earth.com/news/black-hole-is-starving-its-host-galaxy-of-star-forming-fuel/" target="_blank" rel="noreferrer noopener">galaxies</a>. They are responsible for the continuous birth of new stars that enrich the interstellar medium with heavier elements. This constant recycling of material is key to the development of future generations of stars and planets.&nbsp;



Furthermore, the study of these regions helps astronomers understand the fundamental processes that govern the life cycles of stars and the overall dynamics of the universe.



<h2 class="wp-block-heading" id="h-the-local-group">The Local Group</h2>



The Local Group is a collection of over 80 galaxies that includes the Milky Way, the Andromeda Galaxy, and the Triangulum Galaxy, along with numerous smaller dwarf galaxies. These galaxies are bound together by gravity and span a region roughly 10 million light-years across.&nbsp;



The <a href="https://www.earth.com/news/milky-ways-thin-disk-is-billions-of-years-older-than-we-thought/" target="_blank" rel="noreferrer noopener">Milky Way</a> and Andromeda are the dominant members, with their respective satellite galaxies orbiting them.&nbsp;



The Local Group is part of a larger structure known as the Virgo Supercluster, and its galaxies are moving toward the gravitational center of the Local Group, contributing to its dynamic nature.&nbsp;



<h2 class="wp-block-heading" id="h-large-magellanic-cloud">Large Magellanic Cloud</h2>



The Large Magellanic Cloud (LMC) is the fourth largest galaxy in the Local Group and can be seen with the naked eye from the Southern Hemisphere.&nbsp;



This irregular dwarf galaxy is home to the Tarantula Nebula, one of the most active star-forming regions in our cosmic neighborhood.&nbsp;



The Large Magellanic Cloud played a key role in astronomical history, particularly when the supernova SN 1987A was observed, providing valuable insights into stellar evolution.&nbsp;



The LMC's interaction with the Milky Way, along with its own companion, the Small Magellanic Cloud, is believed to influence its shape and star formation activity. Its proximity and unique properties make it a crucial object of study for understanding <a href="https://www.earth.com/news/massive-galactic-explosion-provides-clues-about-galaxy-evolution/" target="_blank" rel="noreferrer noopener">galaxy evolution</a>, star formation, and the dynamics of interacting galaxies.



Image Credit: NASA, ESA, and STScI



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Hubble captures a stunning stellar nursery

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

Today's Image of the Day from the European Space Agency features the Southern Ring Nebula, also known as NGC 3132.



The nebula is located about 2,000 light-years away from Earth in the constellation Vela. This remarkably detailed image was created using data from Webb’s Near-Infrared Camera (NIRCam).



The Southern Ring Nebula is one of the more famous examples of planetary nebulae. It is often studied for its beauty and valuable insights into the end stages of stellar evolution.



<h2 class="wp-block-heading" id="h-stars-power-the-southern-ring-nebula-nbsp">Stars power the Southern Ring Nebula&nbsp;</h2>



The <a href="https://www.earth.com/news/dragons-egg-nebula-is-a-truly-stunning-sight-to-behold/" target="_blank" rel="noreferrer noopener">nebula</a> is powered by two central stars in a binary system. The brighter star is actually a less massive companion. The fainter, dimmer star is the dying, hot central star that has shed its outer layers to form the nebula. 



The dimmer star is a white dwarf and is responsible for the ionization of the gas in the nebula, causing it to glow.



“The bright star at the center of NGC 3132, while prominent when viewed by NASA’s Webb Telescope in near-infrared light, plays a supporting role in sculpting the surrounding nebula," noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



"A second star, barely visible at lower left along one of the bright star’s diffraction spikes, is the nebula’s source. It has ejected at least eight layers of gas and dust over thousands of years.” 



“But the bright central star visible here has helped ‘stir’ the pot, changing the shape of this planetary nebula’s highly intricate rings by creating turbulence." 



ESA explained that the pair of stars are locked in a tight orbit, which leads the dimmer star to spray ejected material in a range of directions as they orbit one another, resulting in these jagged rings.



<h2 class="wp-block-heading" id="h-key-characteristics-of-the-southern-ring-nebula-nbsp">Key characteristics of the Southern Ring Nebula&nbsp;</h2>



The Southern Ring Nebula displays a complex structure with multiple layers of gas and dust. 



The outer shells of the nebula consist of hydrogen and other elements that were ejected from the dying star in previous stages of its <a href="https://www.earth.com/news/young-stellar-objects-observing-the-early-lives-of-stars/" target="_blank" rel="noreferrer noopener">evolution</a>. These layers are illuminated by ultraviolet radiation from the central white dwarf.



<h3 class="wp-block-heading" id="h-coloration">Coloration</h3>



The colors seen in the Southern Ring Nebula come from the different gases present. For example, hydrogen emits red light, while oxygen emits blue-green light. 



These colors help astronomers study the composition and dynamics of the nebula.



<h3 class="wp-block-heading" id="h-size-and-shape">Size and shape</h3>



The nebula spans about half a light-year in diameter. Its intricate, symmetrical structure provides valuable insights into the late stages of <a href="https://www.earth.com/news/star-collapse-black-hole-instead-of-supernova-vanish-from-sky/" target="_blank" rel="noreferrer noopener">stellar evolution</a>, especially the processes involved in the shedding of outer layers by dying stars.



<h2 class="wp-block-heading" id="h-spotlights-from-the-bright-star">Spotlights from the bright star</h2>



ESA noted that hundreds of straight, brightly-lit lines pierce through the rings of gas and dust. “These ‘spotlights’ emanate from the bright star and stream through holes in the nebula like sunlight through gaps in a cloud."



“But not all of the starlight can escape. The density of the central region, set off in teal, is reflected by how transparent or opaque it is. Areas that are a deeper teal indicate that the gas and dust are denser - and light is unable to break free.”



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



According to ESA, this is not only a crisp image of a planetary nebula - it also shows us objects in the vast distances of space behind it. The transparent red sections of the nebula are filled with distant <a href="https://www.earth.com/news/galaxies-have-hearts-and-lungs-that-help-them-live-longer/" target="_blank" rel="noreferrer noopener">galaxies</a>.



“Look for the bright angled line at the upper left. It is not starlight - it is a faraway galaxy seen edge-on. Distant spirals, of many shapes and colors, also dot the scene. Those that are farthest away - or very dusty - are small and red,” said ESA.



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



Vela is a southern constellation that represents the sails of a ship. It was once part of a larger constellation called Argo Navis, which depicted the ship of the mythological hero Jason and the Argonauts. 



In the 18th century, Argo Navis was divided into three separate constellations: Vela (the sails), Carina (the keel), and Puppis (the stern).



Vela is notable for containing several interesting astronomical features. One of its most prominent stars is Gamma Velorum, also known as Suhail or Regor, which is a bright, massive star system consisting of multiple stars.&nbsp;



The constellation also hosts the Vela Supernova Remnant, the remains of a <a href="https://www.earth.com/news/supernova-explosions-could-damage-distant-planets/" target="_blank" rel="noreferrer noopener">supernova</a> explosion that occurred about 11,000 years ago. 



This remnant is associated with the Vela Pulsar, a neutron star that formed during the supernova explosion, which is one of the brightest pulsars in the sky.



Vela is best observed in the Southern Hemisphere, where it can be seen in the summer months. Its position along the Milky Way makes it a popular region for both amateur and professional astronomers to explore.



Image Credit: NASA, ESA, CSA, STScI



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Southern Ring Nebula in the constellation Vela 

Today's Image of the Day from the European Space Agency features NGC 6744 - a large, barred spiral galaxy located approximately 30 million light-years away in the constellation Pavo.&nbsp;



The galaxy is often considered a close analog to the <a href="https://www.earth.com/news/uma3-u1-faintest-star-system-found-orbiting-milky-way-galaxy/" target="_blank" rel="noreferrer noopener">Milky Way</a> due to its similar structure and size, spanning about 175,000 light-years across.&nbsp;



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



The image was captured by the <a href="https://www.esa.int/Science_Exploration/Space_Science/Euclid" target="_blank" rel="noreferrer noopener">Euclid</a> space telescope. NGC 6744 stands out as a prime example of the galaxies currently forming the majority of stars in the nearby universe, making it an ideal subject for study with the Euclid mission.&nbsp;



Euclid’s extensive field-of-view allows it to capture the entire galaxy, showcasing not only its large-scale spiral structure but also revealing intricate details on smaller scales across various wavelengths. These details include feather-like dust lanes, known as “spurs,” emerging from the spiral arms.



<h2 class="wp-block-heading" id="h-star-formation-in-ngc-6744">Star formation in NGC 6744</h2>



Euclid's observations enable scientists to count individual stars within NGC 6744, trace the distribution of stars and dust throughout the galaxy, and map the dust associated with the gas that fuels the development of new stars. 



<a href="https://www.earth.com/news/baby-stars-release-sneezes-of-gas-and-dust-as-they-develop/" target="_blank" rel="noreferrer noopener">Star formation</a> is a key process in the growth of galaxies, making these studies crucial for understanding galaxy evolution.



Researchers are utilizing Euclid’s data to explore the relationship between dust, gas, and star formation; to map the distribution of different stellar populations and identify regions of active star formation; and to investigate the underlying physics of spiral galaxy structures.&nbsp;



Spiral arms play a significant role in star formation by compressing gas, yet the precise mechanisms behind this process are still unclear. The presence of “spurs” along NGC 6744’s spiral arms offers valuable insights into the dynamics of star formation within these structures.



<h2 class="wp-block-heading" id="h-discovering-new-dwarf-galaxies-nbsp">Discovering new dwarf galaxies&nbsp;</h2>



Additionally, Euclid's dataset will help scientists identify clusters of old stars (globular clusters) and discover new dwarf galaxies around NGC 6744. Remarkably, Euclid has already identified a new dwarf satellite galaxy of NGC 6744 - a surprising discovery given that the galaxy has been studied extensively.



With Euclid’s detailed observations, scientists are gaining a deeper understanding of the processes shaping galaxies, providing essential clues to the evolution and appearance of the <a href="https://www.earth.com/news/universes-expansion-rate-hubble-tension-puzzles-astronomers/" target="_blank" rel="noreferrer noopener">universe</a>.



<h2 class="wp-block-heading" id="h-more-about-ngc-6744">More about NGC 6744</h2>



NGC 6744's disk is rich in star-forming regions and contains numerous young, bright blue stars. The galaxy's nucleus is slightly elongated and has a bar structure, which influences the motion of the stars and gas within it.&nbsp;



The spiral arms of NGC 6744 are well-defined and extend outward, wrapping around the central bar. Additionally, NGC 6744 has a smaller companion galaxy, NGC 6744A, which is interacting with it, adding to the complexity and interest of this distant system.&nbsp;



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



<a href="https://www.earth.com/news/the-mesmerizing-beauty-of-spiral-galaxies/" target="_blank" rel="noreferrer noopener">Spiral galaxies</a> are one of the most common types of galaxies in the universe, characterized by their distinct, spiral-shaped structure.&nbsp;



The galaxies typically consist of a flat, rotating disk containing stars, gas, and dust, along with a central concentration of stars known as the bulge. This bulge is often surrounded by a halo of older stars.&nbsp;



The spiral arms, which extend from the central bulge, are regions of active star formation and are rich in young, hot stars, giving them a bright, bluish appearance.&nbsp;



These arms are also sites where interstellar gas and dust are concentrated, leading to the formation of new stars.&nbsp;



Spiral galaxies are classified into different types based on the tightness of their spirals and the size of their central bulge, with classifications ranging from tightly wound arms in Sa galaxies to more loosely wound arms in Sc galaxies. The <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>, our home galaxy, is a prime example of a spiral galaxy.



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



Pavo, which means "peacock" in Latin, is a constellation in the southern sky. It was named by the Dutch astronomer Petrus Plancius in the late 16th century, based on observations made during the Dutch explorations of the southern hemisphere. 



Pavo is one of the 12 constellations created by Plancius from the records of explorers Pieter Dirkszoon Keyser and Frederick de Houtman. 



The constellation is known for its distinctive shape, resembling a peacock with a long, curved tail. Pavo is not visible from most of the northern hemisphere, but it can be seen from the southern hemisphere, particularly during the winter months.



The constellation contains several interesting celestial objects, including the star Peacock, also known as Alpha Pavonis, which is the brightest star in the constellation. This star is a blue-white subgiant located about 179 light-years from Earth.



Image Credit: <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>/Euclid/Euclid Consortium/NASA&nbsp;



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Spiral galaxy NGC 6744 in the constellation Pavo

Today's Image of the Day from the European Space Agency features the Little Dumbbell Nebula, also known as Messier 76, located in the constellation Perseus 3,400 light-years away from Earth.



Astronomers captured this image of the Little Dumbbell Nebula to commemorate the 34th anniversary of the Hubble Space Telescope, a joint venture between NASA and the European Space Agency (<a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>).



The snapshot provides not only a breathtaking view but also deep insights into the life cycle of <a href="https://www.earth.com/news/dark-stars-scientists-discover-a-new-type-of-star-powered-by-dark-matter/" target="_blank" rel="noreferrer noopener">stars</a> and the dynamic processes within nebulae.



<h2 class="wp-block-heading" id="h-understanding-messier-76">Understanding Messier 76</h2>



Messier 76 is categorized as a planetary nebula - a term which refers to its round, planet-like appearance when viewed through early, low-power telescopes. 



However, the term is somewhat misleading as planetary nebulae have no connection to actual <a href="https://www.earth.com/news/nasa-finds-17-exoplanets-that-have-oceans-and-possibly-alien-life/" target="_blank" rel="noreferrer noopener">planets</a>. 



Instead, they represent an expansive shell of luminous gases expelled by a dying red giant star, which subsequently collapses into a dense, hot white dwarf. 



This transformation marks the late stages of stellar evolution for medium to low-mass stars.



<h2 class="wp-block-heading" id="h-structure-of-messier-76">Structure of Messier 76</h2>



The structure of Messier 76 is particularly notable. It includes a central ring, giving the appearance of a bar-like feature, with two distinct lobes emanating from either side. 



This formation is believed to be the result of materials ejected by the star during its red giant phase, possibly sculpted by interactions with a companion star. 



Although this binary companion is not visible in current Hubble images, its presence is inferred from the thick disk of dust and gas aligned with its orbital plane. 



The phenomenon of the companion star potentially being absorbed by the primary star, a process akin to stellar cannibalism, is a captivating aspect of the nebula's history.



<h2 class="wp-block-heading" id="h-the-dynamic-environment-of-the-nebula">The dynamic environment of the nebula</h2>



At the core of the nebula, the primary star, now collapsing into a <a href="https://www.earth.com/news/white-dwarf-stars-may-be-billions-of-years-older-than-estimated/" target="_blank" rel="noreferrer noopener">white dwarf</a>, reaches extreme temperatures. This heat is estimated to be 120,000 degrees Celsius - about 24 times hotter than the surface of our Sun. 



This intensely hot remnant is visible as a small, bright point at the center of the nebula. Directly below this, another star can be seen; however, it is merely aligned with the nebula by chance and is not a part of it.



<h2 class="wp-block-heading" id="h-powerful-glow-of-messier-76">Powerful glow of Messier 76</h2>



The dynamics within Messier 76 are driven by powerful forces. The central disk seems to constrict the material, creating two lobes of gas escaping along the rotational axis of the star, perpendicular to the disk.&nbsp;



The lobes are propelled outward by a potent stellar wind, moving at a staggering two million miles per hour. This rapid movement is sufficient to travel the distance from Earth to the <a href="https://www.earth.com/news/timeless-mystery-solved-scientists-uncover-what-is-inside-the-moons-core/" target="_blank" rel="noreferrer noopener">Moon</a> in just over seven minutes.&nbsp;



The collision of the fast-moving gas with older, slower-moving material ejected during the star’s red giant phase results in the stunning glowing effect seen in the nebula. 



The glow, ignited by the ultraviolet radiation from the white dwarf, is a spectacle of colors with red emanating from nitrogen and blue from oxygen.



<h2 class="wp-block-heading" id="h-a-cosmic-moment-in-time">A cosmic moment in time</h2>



Despite its current brilliance, the existence of the Little Dumbbell Nebula is fleeting on a cosmological scale. It is expected to last only about 15,000 years - a mere moment in the lifespan of the <a href="https://www.earth.com/news/dark-energy-is-ripping-the-universe-apart-but-we-arent-sure-how/" target="_blank" rel="noreferrer noopener">universe</a>. 



This brief period highlights the transient nature of such cosmic phenomena, which, while short-lived, provide crucial insights into the mechanics of stellar evolution and the complex interactions within these celestial sculptures.



<h2 class="wp-block-heading" id="h-more-about-messier-76">More about Messier 76</h2>



Messier 76 was discovered by Pierre Méchain in 1780. It was later cataloged by Charles Messier, who included it in his famous list of nebulous objects.



The nebula's faintness and small size require a good telescope to be observed effectively, with larger telescopes able to reveal more of its fine details and structure.



Studying Messier 76 helps astronomers understand the life cycle of stars and the processes that occur during the late stages of stellar evolution. 



The materials expelled by planetary nebulae like Messier 76 eventually contribute to the interstellar medium, from which new stars and planetary systems may form.



Image Credit: ESA Space Agency&nbsp;



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Secrets of the Little Dumbbell Nebula  

Today's Image of the Day from the European Space Agency features the galaxy I Zwicky 18, which was captured in remarkable detail by the James Webb Space Telescope.



I Zwicky 18 is a blue compact dwarf <a href="https://www.earth.com/news/newly-discovered-stars-milky-way-are-old-as-universe/" target="_blank" rel="noreferrer noopener">galaxy</a> located approximately 59 million light-years away in the constellation Ursa Major.&nbsp;



<h2 class="wp-block-heading" id="h-star-formation-in-i-zwicky-18">Star formation in I Zwicky 18</h2>



The galaxy is notable for its relatively young appearance and the fact that it contains very few heavy elements. These characteristics indicate that it has experienced little <a href="https://www.earth.com/news/baby-stars-release-sneezes-of-gas-and-dust-as-they-develop/" target="_blank" rel="noreferrer noopener">star formation</a> compared to other galaxies of similar age.



“The galaxy was first identified by Swiss astronomer Fritz Zwicky in the 1930’s and resides roughly 59 million light-years from Earth,” noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>. “This galaxy has gone through several sudden bursts of star formation.”&nbsp;



According to ESA, I Zwicky 18 is typical of the kinds of galaxies that inhabited the early universe and is much smaller than our <a href="https://www.earth.com/news/runaway-star-j1249-36-spotted-trying-to-escape-our-milky-way-galaxy/" target="_blank" rel="noreferrer noopener">Milky Way</a>.



<h2 class="wp-block-heading" id="h-webb-telescope-image-of-the-galaxy">Webb telescope image of the galaxy</h2>



“Two major starburst regions are embedded in the heart of the galaxy. The wispy brown filaments surrounding the central starburst region are bubbles of gas that have been heated by stellar winds and intense ultraviolet radiation unleashed by hot, young stars,” noted ESA.



“A companion galaxy resides nearby to the dwarf galaxy, which can be seen at the bottom of the wider-field image. The companion may be interacting with the dwarf galaxy and may have triggered that galaxy's recent star formation.”&nbsp;



ESA explained that the “orange blobs” surrounding the galaxy are the dim glow from ancient fully formed galaxies at much larger distances.



<h2 class="wp-block-heading" id="h-key-characteristics-of-i-zwicky-18">Key characteristics of I Zwicky 18</h2>



As previously mentioned, the galaxy has a very low abundance of elements heavier than hydrogen and helium, suggesting that it has not undergone significant stellar processing.



<h3 class="wp-block-heading" id="h-young-stellar-population-nbsp">Young stellar population&nbsp;</h3>



Despite its old age, I Zwicky 18 contains many young, hot stars. This suggests that it might have experienced a burst of <a href="https://www.earth.com/news/hubble-detects-awe-inspiring-newborn-star/" target="_blank" rel="noreferrer noopener">star formation</a> relatively recently in its history.



<h3 class="wp-block-heading" id="h-interstellar-medium-nbsp">Interstellar medium&nbsp;</h3>



The galaxy has a high density of gas, which is a prime ingredient for star formation. This gas is mostly in the form of hydrogen.



<h3 class="wp-block-heading" id="h-unusual-characteristics">Unusual characteristics</h3>



Its characteristics are more typical of primordial galaxies found in the early universe, making it a valuable object of study for understanding galaxy formation and evolution.



Ultimately, I Zwicky 18 provides insights into the conditions and processes that might have been prevalent in the early universe.



<h3 class="wp-block-heading" id="h-life-cycles-of-stars-and-dust">Life cycles of stars and dust</h3>



The image was captured as part of a Webb program to study the life cycle of dust in I Zw 18.&nbsp;



“Scientists are now building off of previous research with Hubble obtained at optical wavelengths, studying individual dusty stars in detail with Webb’s equivalent spatial resolution and sensitivity at infrared wavelengths.”&nbsp;



ESA noted that this galaxy is of particular interest as its content of elements heavier than helium is one of the lowest of all known <a href="https://www.earth.com/news/early-galaxy-formation-occurred-much-faster-than-we-thought/" target="_blank" rel="noreferrer noopener">galaxies</a> in the local universe.&nbsp;



“Such conditions are thought to be similar to those in some of the first star-forming galaxies at high redshift, so the Webb study of I Zw 18 should shed light on the life-cycle of stars and dust in the early universe.”



<h2 class="wp-block-heading" id="h-the-constellation-ursa-major">The constellation Ursa Major </h2>



Ursa Major, also known as the Great Bear, is one of the most prominent and easily recognizable constellations in the northern sky. 



Its name, "Ursa Major," means "Great Bear" in Latin, and it has been a significant part of various mythologies and star lore across cultures for thousands of years. 



One of the most famous asterisms within Ursa Major is the Big Dipper, a group of seven bright stars that form a shape resembling a ladle or dipper. The Big Dipper is often used as a navigation tool because it points to Polaris, the North Star, located in the nearby constellation Ursa Minor.



Ursa Major is best viewed in the northern hemisphere and is circumpolar, meaning it is visible year-round for much of the Northern Hemisphere. Its position changes with the seasons, rotating around Polaris, the North Star.



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



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Dwarf galaxy provides a window into the early universe

Have you ever looked back and felt like the years just vanished overnight? You're not the only one. Many of us notice that as we age, our perception of time changes. 



Days and years seem to speed by, leaving us wondering what changed. Is it just our busy lives, or is there something deeper happening in our brains?



Scientists are diving into this age-old mystery to uncover why time feels like it's racing against us. 



<h2 class="wp-block-heading" id="h-human-perception-of-time">Human perception of time</h2>



From changes in how our <a href="https://www.earth.com/news/nature-experiences-alter-time-perception/" target="_blank" rel="noreferrer noopener">minds process information</a> to the routines that shape our daily lives, there's a lot going on behind the scenes.



Adrian Bejan, a researcher at <a href="https://www.duke.edu" target="_blank" rel="noreferrer noopener">Duke University</a> with decades of experience, offers a fascinating perspective on this phenomenon. 



He suggests that our perception of time changes due to physical alterations in our brains and bodies as we age.



But let's unpack this idea step by step. Why do some days feel longer or shorter than others? And why does time seem to fly by as we get older?



<h2 class="wp-block-heading" id="h-clock-time-vs-mind-time">"Clock time" vs. "mind time"</h2>



According to Bejan, there's a distinction between measurable clock time and the time <a href="https://www.earth.com/news/slow-motion-exercise-changes-our-perception-of-time/" target="_blank" rel="noreferrer noopener">perceived by our minds</a>. 



He explains, "The measurable ‘clock time’ is not the same as the time perceived by the human mind. The ‘mind time’ is a sequence of images, i.e., reflections of nature that are fed by stimuli from sensory organs."



In simpler terms, our brains process a series of mental images based on what we see, hear, and experience. 



When we're young, our brains receive and process these images more rapidly. As we age, this processing slows down due to <a href="https://www.earth.com/news/heart-rate-influences-our-perception-of-time/" target="_blank" rel="noreferrer noopener">physical changes</a> like the degradation of neural pathways.



<h2 class="wp-block-heading" id="h-why-some-days-feel-longer">Why some days feel longer</h2>



Have you noticed that days filled with new experiences or productivity seem longer? That's because your mind is processing more information and creating more mental images. 



When you're well-rested, your <a href="https://www.earth.com/news/our-brains-bend-time-to-adapt-to-lifes-rhythm/" target="_blank" rel="noreferrer noopener">brain operates</a> more efficiently, allowing you to take in more of the world around you.



Think about athletes who perform best when they're rested. "Lack of rest makes you miss plays, unable to anticipate, unable to see the ball before it arrives," Bejan notes. 



The same goes for students taking exams; a well-rested mind can work through problems more thoroughly, making the exam period feel longer.



<h2 class="wp-block-heading" id="h-perception-of-time-based-on-routine">Perception of time based on routine</h2>



Cindy Lustig, a psychology professor at the <a href="https://umich.edu/" target="_blank" rel="noreferrer noopener">University of Michigan</a>, offers another angle. She points out that as we age, our lives often become more routine. 



"When we are older, we tend to have lives that are more structured around routines, and fewer of the big landmark events that we use to demarcate different epochs of the ‘time of our lives,’" says Lustig.



With fewer new experiences, our brains lump similar days and weeks together. This can make time feel like it's passing more quickly because there are <a href="https://www.earth.com/news/children-and-adults-perceive-time-differently/" target="_blank" rel="noreferrer noopener">fewer memorable events</a> to distinguish one period from another.



<h2 class="wp-block-heading" id="h-social-media-s-impact-on-time-perception">Social media's impact on time perception</h2>



In today's digital age, excessive use of social media can also distort our <a href="https://www.earth.com/news/astrophysicist-says-hes-cracked-the-equation-for-time-travel/" target="_blank" rel="noreferrer noopener">sense of time</a>. When we dive into our favorite apps, we're met with an endless stream of posts, videos, and updates that continuously stimulate our senses. 



This constant engagement can make minutes turn into hours without us noticing. The design of these platforms often encourages prolonged usage through features like infinite scrolling and autoplay videos, which can trap us in a loop where we lose track of how much time has actually passed.



Moreover, excessive use of social media can lead to sleep deprivation, especially when we stay up late scrolling through our feeds. 



Lack of adequate sleep affects our <a href="https://www.earth.com/news/time-cells-in-the-brain-are-key-to-complex-learning/" target="_blank" rel="noreferrer noopener">cognitive functions</a>, making it harder for us to process information efficiently. This can further alter our perception of time, making days feel shorter and less memorable.



<h2 class="wp-block-heading" id="h-physical-changes-in-the-aging-brain">Physical changes in the aging brain</h2>



Bejan emphasizes that physical changes in our brains contribute significantly to this <a href="https://www.earth.com/news/meditation-reveals-common-altered-states-of-consciousness/" target="_blank" rel="noreferrer noopener">altered perception</a>. 



"The rate at which changes in mental images are perceived decreases with age because of several physical features that change with age: saccades frequency, body size, pathways degradation, etc.," he explains.



As our neural pathways degrade over time, our brains take longer to process new information. 



This slower processing speed means we're generating fewer mental images in the same amount of clock time, making time seem to pass faster.



<h2 class="wp-block-heading" id="h-friendly-debate-among-experts">Friendly debate among experts</h2>



While Bejan's theory is compelling, Lustig isn't entirely convinced it tells the whole story. 



She challenges some of his points, especially regarding physical changes like head size affecting perception. 



"He makes some argument about the length of the optic nerve related to head size, and I will let you judge whether an 80-year-old has a substantially larger head than a 25-year-old," Lustig remarks.



<h2 class="wp-block-heading" id="h-what-s-really-going-on-with-time">What's really going on with time?</h2>



The truth might be a blend of both perspectives. Our perception of time likely changes due to a combination of physical changes in our brains and the way we experience life as we age. 



With fewer novel experiences and a slower processing speed, time seems to accelerate.



But here's something to ponder: Can we slow down our perception of time by actively seeking new experiences and staying mentally engaged? It's worth considering.



Perhaps the <a href="https://www.earth.com/news/mindfulness-can-lead-to-altered-states-of-consciousness/" target="_blank" rel="noreferrer noopener">key lies in mindfulness</a> and breaking out of routines. By introducing variety into our lives and challenging our minds, we might recapture that youthful sense of time stretching out before us.



Have you tried picking up a new hobby or exploring a new place recently? How did it affect your perception of time?



<h2 class="wp-block-heading" id="h-time-perception-and-the-human-experience">Time, perception, and the human experience</h2>



To sum it all up, our sense that time speeds up as we age seems to stem from both physical changes in our brains and the routines we fall into over the years.



As we get older, our brains process new information more slowly due to the degradation of neural pathways.



This slower processing means we perceive fewer <a href="https://www.earth.com/news/how-do-dreams-influence-our-perceptions/" target="_blank" rel="noreferrer noopener">mental images</a> in the same amount of clock time, making days and years feel like they pass more quickly.



Meanwhile, as we get older, we tend to have more structured lives filled with routines and fewer novel experiences. 



This lack of new events makes it harder for our brains to distinguish one day from the next, contributing to the sensation that time is slipping away.



While scientists like Bejan and Lustig continue to explore this intriguing topic, one thing is clear: our perception of time is deeply personal and influenced by many factors.



By actively seeking new experiences and staying mentally engaged, we might just slow down our perception of time and make each moment count a little more.



The full study was published in the journal <a href="https://www.cambridge.org/core/journals/european-review/article/why-the-days-seem-shorter-as-we-get-older/2CB8EC9B0B30537230C7442B826E42F1" target="_blank" rel="noreferrer noopener">European Review</a>.



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Time flies by much faster as we get older, and now we know why

Have you ever looked back and felt like the years...

Turtles are fascinating reptiles known for their distinctive shells, which serve as both armor and protection. They've been around for over 200 million years, making them some of the oldest living creatures on Earth. 



You can find turtles in a variety of environments, from the depths of the ocean to freshwater ponds and even on land. Their ability to adapt to different habitats has allowed them to thrive across the globe, with hundreds of species showcasing a wide range of sizes, colors, and behaviors.



And where does this impressive ability to adapt come from? Apparently, it's their genome, which is proving to be very different from that of most other animals studied so far.



<h2 class="wp-block-heading" id="h-insights-into-genetic-blueprints">Insights into genetic blueprints</h2>



DNA molecules, with their long strands of nucleotides, carry extensive genetic data essential for life. How this genetic blueprint is stored in cells influences how it is read and used.&nbsp;



During cell division, DNA is tightly coiled around proteins, forming chromatin structures within chromosomes. 



After division, the chromosomes relax, and chromatin loosens, creating unique folding and looping patterns that determine which genes are activated or repressed. 



New research led by <a href="https://www.iastate.edu/" target="_blank" rel="noreferrer noopener">Iowa State University</a> offers insights into these processes, with implications for understanding evolution and potentially aiding biomedical research.



Study senior author Nicole Valenzuela is a professor of ecology, evolution, and organismal biology at Iowa State University.&nbsp;



“The three-dimensional structure of the chromatin when it’s folded matters for gene regulation. Where chromatin physically sits in the nucleus matters,” said Valenzuela.



“<a href="https://www.earth.com/news/how-do-animals-balance-their-sex-chromosomes/" target="_blank" rel="noreferrer noopener">Chromosome</a> folding remains a bit of a black box. We’ve learned a lot about it, but it’s still just the tip of the iceberg.”



<h2 class="wp-block-heading" id="h-role-of-chromatin-in-gene-regulation">Role of chromatin in gene regulation</h2>



In the post-division interphase stage of the cell cycle, the chromatin’s shape and location impact gene expression by bringing distant <a href="https://www.earth.com/news/plants-use-dna-duplication-to-increase-their-resilience/" target="_blank" rel="noreferrer noopener">DNA</a> regions into close contact.&nbsp;



For example, enhancers (DNA segments that promote gene expression) and gene promoters (regions that initiate transcription) can interact more readily in open, accessible regions of chromatin.&nbsp;



On the other hand, DNA in tightly packed chromatin regions remains less active. 



Through analyzing these contact points, researchers have developed models to map chromatin configurations across various species, such as humans, mice, birds, and more recently, <a href="https://www.earth.com/news/turtles-with-unique-features-are-most-likely-to-go-extinct/" target="_blank" rel="noreferrer noopener">turtles</a>.



<h2 class="wp-block-heading" id="h-unique-discovery-in-turtle-genomes">Unique discovery in turtle genomes</h2>



In a recent paper published in the journal <a href="http://dx.doi.org/10.1101/gr.279443.124" target="_blank" rel="noreferrer noopener">Genome Research</a>, Valenzuela’s team described the chromatin arrangement in the genomes of two turtle species, the spiny softshell and northern giant musk turtles, uncovering a structure previously unobserved in other organisms.&nbsp;



Chromosomes have two essential elements: the centromere, a constriction point, and telomeres, which cap each chromosome end. In humans, chromosomes occupy separate regions in the nucleus.&nbsp;



However, in some animals, like marsupials, centromeres cluster, while in birds, telomeres come together.&nbsp;



Turtles, interestingly, are the first species where both telomeres and centromeres align near each other, suggesting a unique chromatin arrangement.



“It’s possible this is the ancestral condition of amniotes, from which mammals, birds, and reptiles evolved in different patterns,” Valenzuela noted.&nbsp;



“The turtles may be showing us what existed at the beginning, shedding light on the evolution of vertebrate <a href="https://www.earth.com/news/genome-mapping-completed-for-dozens-of-common-animals/" target="_blank" rel="noreferrer noopener">genomes</a>.”



<h2 class="wp-block-heading" id="h-turtle-genomes-and-biomedical-science">Turtle genomes and biomedical science</h2>



Uncovering the chromatin structure in turtles and how it adapts to environmental changes could be valuable for biomedical science.&nbsp;



For example, some turtle species can survive weeks without oxygen, which could have implications for treating <a href="https://www.earth.com/news/could-blood-type-determine-your-stroke-risk/" target="_blank" rel="noreferrer noopener">strokes</a>. 



Similarly, understanding how certain turtles withstand extreme cold might inform techniques for cryogenic preservation of human tissues.



“We want to understand more about why different lineages are different in some aspects and why they’re the same in others, what parts we share and what parts differ,” Valenzuela explained.&nbsp;



“If we can reconstruct the evolutionary history of the changes that have taken place, we will be able to tell much more about how the differences in the packaging of the DNA and the folding of chromosomes might be affecting the traits we’re interested in, how genes are regulated, and how vertebrate genomes evolve.”



Additionally, understanding turtles’ chromatin structure could aid conservation efforts, offering insights into how environmental changes impact their biology and potential adaptations.



<h2 class="wp-block-heading" id="h-future-research-directions">Future research directions</h2>



Valenzuela’s lab plans to extend their research to study more turtle species, adding to the current work on spiny softshell and northern giant musk turtles. 



Her team has already gathered data on four additional species, aiming to see if similar chromatin structures appear in genomes across different turtle lineages. 



The researchers are also interested in comparing turtle chromatin organization to that of other reptiles, such as <a href="https://www.earth.com/news/climate-and-ecology-shaped-250-million-years-of-crocodile-evolution/" target="_blank" rel="noreferrer noopener">crocodiles</a>, lizards, and snakes, to explore whether they share structural patterns.



To gain deeper insights, the team will study liver organoids - lab-grown tissue mimics they have developed for three turtle species. 



These organoids offer a simplified view of liver tissue, allowing the researchers to observe how chromatin folding might influence cellular function. 



Future work will include advanced mapping techniques that provide high-resolution chromatin data, helping to clarify how 3-D chromatin structures change over time and under various environmental conditions.



“To really do genotype-to-phenotype mapping, we have to get to this level of complexity,” Valenzuela concluded.



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Turtles have genomes unlike any other animal studied so far

Turtles are fascinating reptiles known for their distinctive shells, which...

Two years of severe drought in the State of Amazonas is having a devastating impact on one of the Amazon's noteworthy achievements - the sustainable economy based on catching the gargantuan pirarucu fish. This sustainability is now facing a dangerous headwind.



Almost 6,000 people residing by the rivers in Amazonas State, Brazil, are legally permitted to fish for this mammoth creature.



Regrettably, they have witnessed a dramatic decrease in pirarucu catches, combined with escalating costs. This has led to a widespread call for governmental support, and the urgent need to devise a strategy to adapt to the demands of our changing climate.



In the previous year, the catch reached only 70% of the 100,443 fish quota sanctioned by the government.



As we are in the height of the current year's season (which runs from June to November) many communities are yet to commence their <a href="https://www.earth.com/news/sustainable-fishing-must-be-redefined-to-halt-ocean-destruction/" target="_blank" rel="noreferrer noopener">fishing</a> due to the prevailing conditions. The outlook for this year's catch is far from optimistic.



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



Commencing in the Mamiraua region 25 years ago, managed fishing of the pirarucu has seen significant expansion. 



The successful management of the resource saved the Amazon's largest fish from becoming extinct and is now a vital source of income for locals in 10 sustainable conservation units and eight Indigenous territories. These areas boast negligible deforestation rates.



The giant pirarucu fish, that can weigh up to 200 kilograms (440 pounds), were historically resistant to climate changes, including <a href="https://www.earth.com/news/the-amazon-rainforest-and-the-looming-threat-of-drought/" target="_blank" rel="noreferrer noopener">droughts</a>.



However, today's low water levels have left Amazon fishers stranded, unable to transport their catch from isolated lakes to major rivers and cities.



In several areas, water levels decreased so rapidly that the transport connection was severed before the <a href="https://www.earth.com/news/early-summer-fishing-shrinks-atlantic-salmon-size-over-time/" target="_blank" rel="noreferrer noopener">fishing season</a> even started.



<h2 class="wp-block-heading" id="h-amazon-fishers-feel-the-impact">Amazon fishers feel the impact</h2>



In the São Raimundo community in the Medio Jurua region, fishing is commencing with a two-month delay, reflecting the current widespread situation. 



To mitigate the impact, Coletivo Pirarucu, an organization representing 2,500 families living by the river, along with Indigenous families, has called for an extension of the fishing season until the end of January.



Even major rivers are not spared. As a result, navigation has been difficult, resulting in escalating costs and uncertainty amongst fishers.



The journey to transport fish from Carauari, a principal pirarucu producer, to the largest city of the <a href="https://www.earth.com/news/smallest-pollution-particles-affect-rainfall-in-the-amazon/" target="_blank" rel="noreferrer noopener">Amazon</a>, Manaus, usually takes up to four days. However, during the drought's peak, this journey extended to ten days, and the transport cost doubled.



According to researcher Adalberto Luis Val from the <a href="https://www.gov.br/inpa/pt-br" target="_blank" rel="noreferrer noopener">National Institute for Amazonian Research</a>, even the robust pirarucu is not immune to climate change. 



“No fish can regulate body temperature. Then there's water scarcity. As its level drops, you start to get a high amount of suspended material, leading to sludge build-up. It sticks to the gill area, blocking the processes that occur there," explained Val.



<h2 class="wp-block-heading" id="h-seeking-support-for-amazon-fishers">Seeking support for Amazon fishers</h2>



Coletivo Pirarucu is advocating for fishermen to receive compensation for the losses brought on by climate change.



They issued an open letter last week, expressing their concerns and calling for the development of “climate change adaptation and mitigation strategies.”



At a higher level, James Bessa, a federal official responsible for pirarucu management, confirmed that Ibama, Brazil's environmental body, is collaborating with other public bodies and local fishing associations to minimize the impact of <a href="https://www.earth.com/news/droughts-and-extreme-weather-events-are-escalating/" target="_blank" rel="noreferrer noopener">extreme weather events</a>.



Lastly, Adevaldo Dias, a riverine leader and president over the Chico Mendes Memorial, has made a plea for climate justice. 



“The Indigenous and riverine peoples have minimal impact on the environment. We know that conserving the forest benefits both us and those outside it. And when extreme climate events occur, they are the most vulnerable," said Dias.



<h2 class="wp-block-heading" id="h-the-uncertain-future-of-the-fishing-trade">The uncertain future of the fishing trade</h2>



The ongoing droughts have raised pressing questions about the sustainability of the pirarucu fishing trade and the resilience of the communities that depend on it. 



Experts fear that without swift and effective intervention, the balance achieved through decades of conservation efforts could unravel.



The challenges faced by riverine and Indigenous communities extend beyond immediate economic hardship; they highlight a deeper vulnerability tied to the changing climate.



Efforts to protect the pirarucu and ensure that its harvest remains a cornerstone of the Amazon's sustainable economy are at a crossroads.



If the current trend continues, the once-thriving pirarucu trade may face further obstacles, impacting food security, local livelihoods, and conservation outcomes.



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Amazon drought: Fishers in crisis as their biggest catch disappears

Two years of severe drought in the State of Amazonas...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the Great Lakes &#8211; Superior, Michigan, Huron, Erie, and Ontario &#8211; captured by the Copernicus Sentinel-3 mission.&nbsp;



According to ESA, the lakes represent the largest surface of freshwater in the world with a combined area of around 244,000 square kilometers, covering an area larger than the United Kingdom.



The lakes were formed around 100,000 years ago, when a massive ice sheet and giant glaciers transformed the landscape across most of Canada and part of the United States. As the ice melted, holes left behind from glaciers filled with meltwater and formed thousands of lakes. 



Huron is one of the five American great lakes and one of the largest freshwater lakes. It forms a natural border between the American state of Michigan and the Canadian province of Ontario.



Video Credit: ESA&nbsp;



&#8211;&#8212;



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

The Great Lakes of North America