Today's Image of the Day from the European Space Agency features Messier 78 (M78), a reflection nebula located in the constellation Orion about 1,350 light-years away from Earth. 



This image was released as part of the initial series of observations from ESA's <a href="https://www.esa.int/Science_Exploration/Space_Science/Euclid" target="_blank" rel="noreferrer noopener">Euclid space mission</a>.&nbsp;



All data collected during these early observations, including a series of incredible <a href="https://www.esa.int/Science_Exploration/Space_Science/Euclid/Euclid_s_first_images_the_dazzling_edge_of_darkness" target="_blank" rel="noreferrer noopener">new views</a> of the nearby universe, is available to the public. 



<h2 class="wp-block-heading" id="h-image-of-messier-78">Image of Messier 78</h2>



Featured here is a high-resolution, detailed segment of a larger image showcasing Messier 78, a dynamic region of star formation obscured by cosmic dust.&nbsp;



This specific view highlights how young stars generate winds of charged particles, carving out “cavities” in the molecular clouds around them.&nbsp;



The blue hues in the image represent ionized atomic hydrogen, which is a primary component of the cloud, while the red indicates the absorption and scattering of light by dust particles.



The image captures hundreds of stars varying in brightness, illuminating their nebulous, purple surroundings. A dark, arch-like structure stretches from the upper left to the bottom right of the frame, merging into the densest, darkest clouds at the image’s base.



<h2 class="wp-block-heading" id="h-active-site-of-star-formation-nbsp">Active site of star formation&nbsp;</h2>



Messier 78 is not just a single nebula but part of a larger complex of stars and nebulous regions in <a href="https://www.earth.com/news/orion-nebula-destroys-an-oceans-worth-of-water-every-month/" target="_blank" rel="noreferrer noopener">Orion</a>, which includes various other objects like dark nebulae that are visible as patches blocking light from behind.



This region is an active site of star formation, featuring many young stars and protostars, which are stars in the early stages of formation.&nbsp;



<h2 class="wp-block-heading" id="h-viewing-messier-78">Viewing Messier 78</h2>



M78 is easily observable with small telescopes, and it appears as a hazy patch of light with two prominent stars near its center, which illuminate the surrounding dust.&nbsp;



The nebula is also a favorite among amateur astronomers for its beauty and relatively bright appearance.



<h2 class="wp-block-heading" id="h-subject-of-scientific-interest-nbsp">Subject of scientific interest&nbsp;</h2>



Messier 78 is fascinating not only for its visual beauty but also for its scientific interest, particularly in the study of <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> and interstellar matter.&nbsp;



The nebula consists of dense, cold gas and dust, which are essential ingredients for the birth of new stars.&nbsp;



The intense blue light that characterizes M78 is due to the reflection of starlight off these dust particles, a process known as scattering.



<h2 class="wp-block-heading" id="h-region-surrounding-messier-78-nbsp">Region surrounding Messier 78&nbsp;</h2>



The region surrounding M78 includes several other interesting features. For instance, there are Herbig-Haro objects within it, which are small patches of nebulosity associated with <a href="https://www.earth.com/news/new-molecule-detected-in-space-where-stars-are-born/" target="_blank" rel="noreferrer noopener">newly born stars</a>.&nbsp;



These objects are formed when gas ejected by young stars collides with clouds of gas and dust at high speeds, creating shock waves that glow brightly.



<h2 class="wp-block-heading" id="h-earliest-stages-of-star-development-nbsp">Earliest stages of star development&nbsp;</h2>



Additionally, infrared observations of M78 have revealed much about the dust and colder objects in the area, which are not visible in optical light.&nbsp;



The observations have helped astronomers identify numerous young stars and brown dwarfs (objects that are too large to be planets and too small to be stars) within the nebula. 



This makes M78 a critical area for studying the earliest stages of star development and the properties of the interstellar medium.



<h2 class="wp-block-heading" id="h-euclid-space-mission-nbsp-0">Euclid space mission&nbsp;</h2>



The <a href="https://www.earth.com/news/new-batch-of-brilliant-images-from-the-euclid-mission-live-up-to-the-hype/" target="_blank" rel="noreferrer noopener">Euclid space mission</a> is a European Space Agency (ESA) mission designed to study the dark universe, particularly focusing on dark energy and dark matter, which are fundamental components that are believed to drive the accelerating expansion of the universe and shape its large-scale structure.&nbsp;



The mission aims to map the geometry of the dark universe and better understand the physics of the cosmos.



<h3 class="wp-block-heading" id="h-observing-billions-of-galaxies-nbsp">Observing billions of galaxies&nbsp;</h3>



Euclid uses two primary scientific instruments: a visible light camera (VIS) and a near-infrared spectrometer and photometer (NISP).&nbsp;



These instruments will allow Euclid to measure the shapes and redshifts of galaxies at distances of up to 10 billion light-years. By surveying more than a third of the sky, the mission is expected to observe several billion galaxies.



<h3 class="wp-block-heading" id="h-studying-the-dark-universe-nbsp">Studying the dark universe&nbsp;</h3>



The data collected will help astronomers in studying the effects of dark matter and dark energy in depth, testing cosmological models, and exploring new theories about the nature of the universe.&nbsp;



The mission, named after the ancient Greek mathematician Euclid, seeks to address key questions related to the structure of the universe and the fundamental laws of physics governing its evolution and expansion.



Image Credit: European Space Agency&nbsp;



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Messier 78: Young stars shine through dense dust

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

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>.&nbsp;



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.&nbsp;



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.&nbsp;



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>.&nbsp;



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 NASA Earth Observatory features the remnants of Lake Razzaza, an artificial lake situated a few miles west of Karbala, Iraq.



The <a href="https://www.earth.com/news/alarming-study-most-of-the-worlds-largest-lakes-are-quickly-losing-water/" target="_blank" rel="noreferrer noopener">lake</a> was created in the late 1970s as a flood control measure to regulate the floodwaters of the Euphrates River. 



Razzaza covers an area of approximately 1,562 square kilometers and is located in a depression where excess water from Lake Habbaniyah is diverted through a controlled escape channel or canal.&nbsp;



<h2 class="wp-block-heading" id="h-the-colors-of-lake-razzaza">The colors of Lake Razzaza</h2>



“The lake, also known as Baḩr al-Milḩ (‘Sea of Salt’ in Arabic), is fed by overflow from Habbaniyah Lake, which lies just outside the top left corner of the image,” noted <a href="https://earthobservatory.nasa.gov/images/153756/iraqs-sea-of-salt" target="_blank" rel="noreferrer noopener">NASA</a>.



“The difference in water color results from the various communities of algae that thrive in the lake depending on the water temperature and salinity.”



“Green areas contain lower salt concentrations than red areas. At times when the lake receives no overflow from Habbaniyah Lake, as shown in this image, most of the lakebed is exposed.”



<h2 class="wp-block-heading" id="h-salinity-of-lake-razzaza">Salinity of Lake Razzaza</h2>



Over the years, the salinity of Lake Razzaza has been increasing due to inadequate water supply from the linked canal and high evaporation rates during Iraq's hot summers.&nbsp;



This rise in <a href="https://www.earth.com/news/salt-pollution-threatens-freshwater-ecosystems/" target="_blank" rel="noreferrer noopener">salinity</a> has led to a decline in fish populations, adversely affecting local fishermen who once relied on the lake for their livelihoods. 



By 2008, only the fish species locally known as "al-Shanik" (Acanthopagrus arabicus), of marine origin and stocked by the government, was reported to survive in the lake.&nbsp;



The lake's fluctuating water levels and increasing salinity have also impacted its recreational appeal, with few recreational areas existing around the lake.&nbsp;



Additionally, the surrounding desert landscape and low cliff shores contribute to its limited accessibility for leisure activities.&nbsp;



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



Despite these challenges, Lake Razzaza remains an important habitat for various bird species. It has been designated an Important Bird Area (IBA) by BirdLife International, supporting significant numbers of wintering waterfowl and serving as a breeding ground for species such as the marbled duck.&nbsp;



The lake's mudflats attract large numbers of waders and shorebirds during migration periods.&nbsp;



The surrounding area features vegetation such as Phragmites australis, Juncus acutus, Aeluropus lagopoides, Salicornia herbacea, and Schoenoplectus litoralis, along with desert shrublands including Tamarix aucherana, Prosopis farcta, and Haloxylon salicornicum.&nbsp;



Mammals reported in this region include Rüppell's fox, golden jackal, Indian grey mongoose, jungle cat, and wildcat.&nbsp;



In recent years, the <a href="https://www.earth.com/news/lakes-are-warming-toward-the-point-of-no-return/" target="_blank" rel="noreferrer noopener">lake</a> has faced environmental challenges due to reduced water inflows and increased evaporation, leading to higher salinity levels and a decline in biodiversity. 



Efforts to address these issues are essential to preserve the ecological and economic significance of Lake Razzaza.



<h2 class="wp-block-heading" id="h-the-euphrates-river-nbsp">The Euphrates River&nbsp;</h2>



The Euphrates River is one of the most significant rivers in the Middle East and holds immense historical, cultural, and ecological importance.&nbsp;



Stretching approximately 2,800 kilometers (1,740 miles), it originates in the mountains of eastern Turkey and flows through Syria and Iraq before merging with the Tigris River to form the Shatt al-Arab, which empties into the Persian Gulf.&nbsp;



The <a href="https://www.earth.com/news/major-plastic-pollution-lurks-beneath-the-surface-of-rivers/" target="_blank" rel="noreferrer noopener">river</a> has been a cradle of civilization for thousands of years, supporting ancient Mesopotamian societies, including Sumer, Akkad, Babylon, and Assyria.



The Euphrates has provided water for irrigation, enabling the development of agriculture in an otherwise arid region. Its floodplains have been vital for sustaining life and fostering the growth of cities along its course.&nbsp;



However, the river also plays a key geopolitical role, as disputes over water usage and dam construction among Turkey, Syria, and Iraq have emerged over the years, impacting water availability downstream.



Ecologically, the Euphrates supports a range of habitats, from wetlands to desert ecosystems, making it home to diverse flora and fauna.&nbsp;



However, modern challenges such as damming, pollution, and climate change threaten its flow and ecological balance. Despite these challenges, the Euphrates remains a symbol of life and resilience in the heart of the Middle East.



The image was captured by an astronaut on the International Space Station (ISS) on September 23, 2024.



Image Credit: NASA



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Lake Razzaza: A shrinking oasis shaped by salinity

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

Today's Image of the Day from NASA features the spiral galaxy NGC 2566, which is located 76 million light-years away in the constellation Puppis. The image was captured by the NASA/ESA Hubble Space Telescope.



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



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



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



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



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



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



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



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



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



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



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



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



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



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



<h2 class="wp-block-heading" id="h-rate-of-star-formation-nbsp-across-galaxies">Rate of star formation&nbsp;across galaxies</h2>



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



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



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



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



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



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



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



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



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



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



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



Image Credit: NASA



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NGC 2566: A cosmic eye in the Puppis constellation

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

Today's Image of the Day from the European Space Agency features the Cat's Eye Nebula (NGC 6543), located about 3,300 light-years from Earth in the constellation Draco.&nbsp;



The nebula's name comes from its eye-like appearance when viewed through a telescope. This particular image, which reveals the <a href="https://www.earth.com/news/horsehead-nebula-webb-telescope-captured-unprecedented-detail/" target="_blank" rel="noreferrer noopener">nebula</a> in stunning detail, was captured by the NASA/ESA Hubble Space Telescope.



<h2 class="wp-block-heading" id="h-planetary-nebulae-nbsp">Planetary nebulae&nbsp;</h2>



According to ESA, the Cat's Eye Nebula is one of the most complex planetary nebulae that has ever been discovered.



“A planetary nebula forms when Sun-like stars gently eject their outer gaseous layers to form bright nebulae with amazing twisted shapes," explained <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



"Until recently, it was thought that shells around planetary nebulae were a rare phenomenon. However, astronomers have instead shown that these rings are likely to be the rule rather than the exception."



<h2 class="wp-block-heading" id="h-appearance-of-the-cat-s-eye-nebula-nbsp">Appearance of the Cat's Eye Nebula&nbsp;</h2>



The central focus of the Cat's Eye is a hot, dying star that has shed its outer layers to form 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>. It is surrounded by concentric gas shells, jets of high-speed gas, and unusual shock-induced knots of gas.



“Although the rings may be the key to explaining the final ‘gasp’ of the dying central star, the mystery behind the Cat’s Eye Nebula’s nested ‘Russian doll’ structure remains largely unsolved,” noted ESA.



<h2 class="wp-block-heading" id="h-rings-around-the-cat-s-eye">Rings around the Cat’s Eye</h2>



“This image, taken with Hubble's Advanced Camera for Surveys (ACS), reveals the full pattern of eleven or more concentric rings, or shells, around the Cat’s Eye. Each ‘ring’ is actually the edge of a spherical bubble seen projected onto the sky - which is why it appears bright along its outer edge.”



According to ESA, observations suggest that the star ejected its mass in a series of pulses at 1,500-year intervals. “These convulsions created dust shells that each contains as much mass as all of the planets in our solar system combined.”



Several explanations have been proposed for this phenomenon, including cycles of magnetic activity similar to our Sun's sunspot cycle, the influence of companion stars orbiting the <a href="https://www.earth.com/news/dying-stars-may-be-a-source-of-gravitational-waves/" target="_blank" rel="noreferrer noopener">dying star</a>, or stellar pulsations.&nbsp;



Another theory suggests that the material is ejected smoothly from the star, with the rings forming later due to the creation of waves in the outflowing material.



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



<a href="https://www.earth.com/news/extrasolar-ocean-planet-discovered-in-the-draco-constellation/" target="_blank" rel="noreferrer noopener">Draco</a> is a constellation in the northern sky that represents a dragon. It's one of the largest constellations, winding between the Big and Little Dippers.&nbsp;



In Greek mythology, Draco is often identified as the dragon Ladon, who guarded the golden apples in the garden of the Hesperides.



Draco is a circumpolar constellation for most northern hemisphere observers, meaning it never sets below the horizon and can be seen all year round.



<h2 class="wp-block-heading" id="h-famous-planetary-nebulae">Famous planetary nebulae </h2>



Planetary nebulae are some of the most beautiful and intriguing objects in the universe.&nbsp;



One of the most famous is the Ring Nebula, or M57, located in the constellation Lyra. This nebula is renowned for its nearly perfect ring shape, which is the result of a dying star shedding its outer layers.&nbsp;



Another well-known planetary nebula is the Helix Nebula, or NGC 7293, often referred to as the "Eye of God" due to its eye-like appearance. The Helix Nebula is one of the closest planetary nebulae to Earth, making it a popular target for amateur astronomers.&nbsp;



The Dumbbell Nebula, or M27, in the constellation Vulpecula, is another striking example. It is named for its resemblance to a dumbbell and is notable for being the first planetary nebula ever discovered, by Charles Messier in 1764.&nbsp;



The Butterfly Nebula, or NGC 6302, is located in the constellation Scorpius. Its name comes from its distinctive bipolar structure, resembling the wings of a butterfly. The nebula's central star is one of the hottest known, with a surface temperature of around 250,000 degrees Celsius.&nbsp;



The Eskimo Nebula, or NGC 2392, in the constellation Gemini, is known for its resemblance to a face surrounded by a fur parka, which gives it its name. Its intricate structure, including filaments and bubble-like shapes, makes it a fascinating object of study. 



These nebulae not only captivate us with their beauty but also provide valuable insights into the life cycles of stars and the processes that shape our galaxy.



Image Credit: NASA/ESA Hubble Space Telescope



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Cat's Eye Nebula in the constellation Draco

Researchers at the Allen Institute have identified a specific brain region in mice where aging triggers significant changes in numerous cell types. The study also pinpointed which cell types undergo the most profound transformations



This new information, published in the journal <a href="http://dx.doi.org/10.1038/s41586-024-08350-8" target="_blank" rel="noreferrer noopener">Nature</a>, points toward potential approaches for slowing or controlling the <a href="https://www.earth.com/news/what-25-years-of-research-revealed-about-brain-aging/" target="_blank" rel="noreferrer noopener">aging</a> process in the brain.



The research was focused on numerous glial cell types - the brain’s “support cells” - that demonstrated considerable shifts in gene activity with age. Among the cells most affected were microglia, border-associated macrophages, oligodendrocytes, tanycytes, and ependymal cells.&nbsp;



The study showed that, in aging brains, the activity of genes linked to <a href="https://www.earth.com/news/fasting-helps-the-body-fight-inflammation-and-chronic-diseases/" target="_blank" rel="noreferrer noopener">inflammation</a> rose, while the activity of genes important for neurons decreased.



<h2 class="wp-block-heading" id="h-aging-hotspot-identified-in-the-brain">Aging hotspot identified in the brain</h2>



The researchers discovered a concentration of these changes in an “aging hotspot,” located in the hypothalamus.&nbsp;



The most significant gene expression changes were discovered in cell types located near the third ventricle of the hypothalamus.



The cells include tanycytes, ependymal cells, and neurons with an important role in food intake, energy homeostasis, metabolism, and how our bodies use nutrients.&nbsp;



This observation hints at a connection between <a href="https://www.earth.com/news/a-healthy-diet-can-reduce-brain-aging/" target="_blank" rel="noreferrer noopener">diet</a>, lifestyle factors, brain aging, and changes that influence susceptibility to age-related brain disorders.



“Our hypothesis is that those cell types are getting less efficient at integrating signals from our environment or from things that we're consuming,” said study lead author Kelly Jin, a scientist at the <a href="https://alleninstitute.org/division/brain-science/" target="_blank" rel="noreferrer noopener">Allen Institute for Brain Science</a>.&nbsp;



“And that loss of efficiency somehow contributes to what we know as aging in the rest of our body. I think that's pretty amazing, and I think it’s remarkable that we're able to find those very specific changes with the methods that we're using.”



<h2 class="wp-block-heading" id="h-analyzing-millions-of-brain-cells">Analyzing millions of brain cells</h2>



The experts employed advanced single-cell RNA sequencing and high-resolution mapping methods created through <a href="https://braininitiative.nih.gov/" target="_blank" rel="noreferrer noopener">The BRAIN Initiative®</a>.&nbsp;



The team analyzed over 1.2 million brain cells taken from mice at two months of age (classified as “young”) and 18 months of age (considered by researchers to be “late middle-aged”).&nbsp;



Mice share critical structural, functional, and genetic features with humans, making them useful for studying how the brain evolves over time.



“Aging is the most important risk factor for <a href="https://www.earth.com/news/alzheimers-disease-attacks-the-brain-in-two-separate-phases/" target="_blank" rel="noreferrer noopener">Alzheimer’s disease</a> and many other devastating brain disorders. These results provide a highly detailed map for which brain cells may be most affected by aging,” said Richard J. Hodes, the director of <a href="https://www.nia.nih.gov/" target="_blank" rel="noreferrer noopener">NIH’s National Institute on Aging</a>.&nbsp;



“This new map may fundamentally alter the way scientists think about how aging affects the brain and also provides a guide for developing new treatments for aging-related brain diseases.”



<h2 class="wp-block-heading" id="h-possible-targets-for-future-therapies">Possible targets for future therapies</h2>



The researchers found that particular clusters of cell types in the hypothalamus had a meaningful drop in the genes essential for neuron functioning, while the genes involved in inflammation rose in activity.&nbsp;



The experts reasoned that examining this hotspot and these cell types more closely could lead to targeted interventions.



“We want to develop tools that can target those cell types,” said Hongkui Zeng, the executive vice president and director of the Allen Institute for Brain Science. “If we improve the function of those cells, will we be able to delay the aging process?”



<h2 class="wp-block-heading" id="h-lifestyle-factors-in-brain-aging">Lifestyle factors in brain aging</h2>



These data support earlier links between aging and metabolic changes, along with evidence suggesting that intermittent fasting or a balanced diet might influence longevity.&nbsp;



While the study did not test dietary patterns directly, it highlights the importance of understanding which brain cells may be “players” in the aging process.



“It’s not something we directly tested in this study,” said Jin. “But to me, it points to the potential players involved in the process, which I think is a huge deal because this is a very specific, rare population of neurons that express very specific genes that people can develop tools for to target and further study.”



<h2 class="wp-block-heading" id="h-preventing-age-related-declines-in-brain-health">Preventing age-related declines in brain health</h2>



The study provides a starting point for deeper inquiries into how diet, lifestyle, or pharmaceuticals might alleviate or slow age-related declines in <a href="https://www.earth.com/news/brain-health-may-literally-be-a-state-of-mind/" target="_blank" rel="noreferrer noopener">brain health</a>. 



By tracking the most vulnerable cell types, researchers hope to devise strategies - whether dietary or pharmaceutical - that help maintain healthy brain function well into old age.



“The important thing about our study is that we found the key players - the real key players - and the biological substrates for this process,” Zeng said.&nbsp;



“Putting the pieces of this puzzle together, you have to find the right players. It’s a beautiful example of why you need to study the brain and the body at this kind of cell type-specific level.”&nbsp;



“Otherwise, changes happening in specific cell types could be averaged out and undetected if you mix different types of cells together.”



As scientists probe further into the link between these specific cells and the hypothalamic region, this line of research sets the stage for developing new methods aimed at preserving cognitive abilities and forestalling age-related diseases. 



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'Aging hotspot' found in the brain may hold the key to longevity 

Researchers at the Allen Institute have identified a specific brain...

He was out prospecting for gold in 2015, when something far heavier than any ordinary rock caught his eye. David Hole believed he had stumbled upon a valuable nugget in Maryborough, just a few hours from Melbourne.



<h2 class="wp-block-heading" id="h-a-curious-find">A curious find</h2>



At first glance, the odd <a href="https://www.earth.com/news/perseverance-rover-finds-best-evidence-yet-life-on-mars-cheyava-falls-rock/">reddish rock</a> looked like it might hold a fortune. Hole tried every method he could think of to see if there was gold buried inside.



Melbourne Museum geologist Dermot <a href="https://scholar.google.com/citations?user=vLYRmCsAAAAJ&amp;hl=en" target="_blank" rel="noreferrer noopener">Henry</a> first examined the object when Hole brought it in, still believing it contained hidden treasure. 



Henry recognized qualities that made the rock stand out from typical specimens that people lug into the museum.



<h2 class="wp-block-heading" id="h-unbreakable-mystery">Unbreakable mystery</h2>



The stone withstood onslaughts with a rock saw, power drills, and even repeated hammer blows. Hole’s attempts to crack it exposed an important detail: the thing was tough in a way that ordinary, gold-containing stones are not.



After a diamond saw finally cut off a thin slice, the internal structure <a href="https://www.smh.com.au/national/prospector-s-mystery-rock-was-no-nugget-but-something-much-rarer-20190716-p527pi.html" target="_blank" rel="noreferrer noopener">showed</a> an abundance of iron and nickel.&nbsp;



It was an <a href="https://www.lpi.usra.edu/meteor/metbullclass.php?sea=h5" target="_blank" rel="noreferrer noopener">H5 ordinary chondrite meteorite</a> weighing 17 kilograms (37.5 pounds), and <a href="https://museumsvictoria.com.au/media-releases/meteorite-found-by-gold-prospector-the-first-found-in-victoria-since-1995-comes-to-museums-victoria/" target="_blank" rel="noreferrer noopener">originally</a> part of the leftover chunks from our Solar System’s early days.



<h2 class="wp-block-heading" id="h-second-largest-of-its-kind">Second largest of its kind</h2>



Experts concluded that this Maryborough meteorite is around <a href="https://museumsvictoria.com.au/media-releases/meteorite-found-by-gold-prospector-the-first-found-in-victoria-since-1995-comes-to-museums-victoria/" target="_blank" rel="noreferrer noopener">4.6 billion years old</a>. It is only the 17th meteorite ever recorded in the Australian state of Victoria and the second-largest single chondritic mass found there.



Bill <a href="https://museumsvictoria.com.au/about-us/staff/dr-bill-birch/" target="_blank" rel="noreferrer noopener">Birch</a>, also from the Melbourne Museum, immediately noticed how unnaturally heavy the stone felt for its size. He recognized the polished, sculpted exterior, shaped was by a fiery descent through Earth’s atmosphere.



<h2 class="wp-block-heading" id="h-why-it-matters">Why it matters</h2>



The researchers say meteorites like this provide vital pieces in the puzzle of how our planetary neighborhood formed. By analyzing their chemical makeup, scientists can learn about conditions that existed long before Earth was fully formed.



When the <a href="https://www.earth.com/news/interstellar-tunnel-found-that-connects-our-solar-system-to-other-stars/">Solar System</a> took shape, it began as a swirling mix of gas and chondrite fragments. Much of this material coalesced into planets, while some lumps never merged and ended up in the asteroid belt between Mars and Jupiter.



<h2 class="wp-block-heading" id="h-unexpected-journey">Unexpected journey</h2>



A cosmic collision in that belt might have dislodged the Maryborough meteorite long ago. It then hurtled through space, entered Earth’s atmosphere, and eventually plopped into the clay where Hole discovered it.



Carbon dating <a href="https://www.publish.csiro.au/RS/RS19002" target="_blank" rel="noreferrer noopener">places</a> its arrival at anywhere between 100 and 1,000 years ago. Observers in the region reported bright fireballs overhead at different times in history, any one of which might have been the final leg of this stone’s cosmic trip.



<h2 class="wp-block-heading" id="h-historic-significance">Historic significance</h2>



Investigations show that meteorites of this size do not surface often in Victoria. Many people <a href="https://www.earth.com/news/supergiant-gold-deposit-find-claims-to-be-the-worlds-largest-discovery-ever/">find gold</a> in Maryborough’s fields, but few come across something formed beyond our planet.



“Meteorites provide the cheapest form of space exploration. They transport us back in time, providing clues to the age, formation, and chemistry of our Solar System (including Earth),” said Henry.



<h2 class="wp-block-heading" id="h-rarity-over-gold">Rarity over gold</h2>



“This is only the 17th meteorite found in Victoria, whereas there’s been thousands of gold nuggets found,” said Henry. That ratio alone underlines how uncommon such objects can be.



Scientists discovered small, metallic chondrules within the space rock. These droplets once floated in a cloud of hot dust in the early Solar System, and eventually hardened into solid rock.



<h2 class="wp-block-heading" id="h-museum-worthy-exhibit">Museum-worthy exhibit</h2>



The Maryborough meteorite was placed on display at the Melbourne Museum. Hole, who never found gold in that rock, later marveled at its grander significance.



Experts classify it as an H5 ordinary chondrite, a type believed to resemble the <a href="https://www.earth.com/news/mantle-heat-shaped-earths-crust-3-billion-years-ago/">material that formed our planet</a>. Learning about its texture and composition may shed light on how Earth evolved.



<h2 class="wp-block-heading" id="h-short-stay-on-earth">Short stay on Earth</h2>



The meteorite’s weathered surface suggests it has not spent more than a few centuries in the soil. Researchers point to several historical newspaper accounts about blazing objects in the sky, any of which could match its rough arrival date.



In July 2019, Henry and Birch, along with other collaborators, published a detailed <a href="https://www.publish.csiro.au/rs/rs19002">paper</a> describing the meteorite's properties. Their study chronicles its structure and chemical makeup, and offers a glimpse at an untouched fragment of our early neighborhood.



<h2 class="wp-block-heading" id="h-surprising-treasure">Surprising treasure</h2>



Hole never got the gold he expected, but he discovered something even more precious to science. His story is a reminder that unusual objects can turn out to be cosmic gifts hiding right under our feet.



Anybody with a backyard might have an interstellar souvenir tucked away in the dirt. In rare cases, that suspiciously heavy rock could be a time capsule from the <a href="https://www.earth.com/news/one-novae-star-explosion-may-be-origin-phosphorus-life/">origins of the Solar System</a>.



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He thought it was gold, but inside this 4.6 billion-year-old meteorite he found something even stranger

He was out prospecting for gold in 2015, when something...

The global livestock industry plays a significant role in the production of greenhouse gases, contributing to climate change in ways that are often overlooked. 



Cows, sheep, and other livestock produce methane, a potent greenhouse gas, during digestion through a process called enteric fermentation. 



In fact, methane has a much higher heat-trapping potential than carbon dioxide, making livestock farming a key driver of global warming. 



Additionally, the industry is responsible for large amounts of carbon dioxide and nitrous oxide emissions, mainly from the use of synthetic fertilizers and land-use changes like deforestation for grazing. 



Together, these emissions make the livestock sector one of the leading contributors to global greenhouse gas levels.



On top of direct emissions, the livestock industry also contributes to <a href="https://www.earth.com/news/global-deforestation-crisis-how-can-we-stop-massive-forest-losses/" target="_blank" rel="noreferrer noopener">deforestation</a> and other forms of environmental degradation through its high demand for resources like water and land.



A substantial amount of land - counting both grazing areas for cattle, pigs, and poultry, and agricultural fields for their feed crops - is devoted to sustaining the world’s 92 billion farm animals.



<h2 class="wp-block-heading" id="h-how-are-pets-involved-with-livestock">How are pets involved with livestock?</h2>



A large portion of pet food is made from animal products, including meat, which requires significant land, water, and energy to produce. 



As a result, the pet food industry indirectly contributes to the environmental problems tied to livestock farming, such as deforestation and greenhouse gas emissions.



Andrew Knight of the <a href="https://www.winchester.ac.uk/" target="_blank" rel="noreferrer noopener">University of Winchester</a>, writing for The Conversation, recently explored the potential environmental benefits of switching all pets to vegan diets. 



If this were somehow possible, how much impact would it have on the planet? Short answer - a lot.



<h2 class="wp-block-heading" id="h-considering-the-impacts-of-pet-diets">Considering the impacts of pet diets</h2>



Efforts to address these challenges have sparked interest in shifting human diets to plant-based alternatives. Yet, as experts increasingly argue, the environmental impact of <a href="https://www.earth.com/news/dog-owners-ages-and-beliefs-influence-their-pet-food-choices/" target="_blank" rel="noreferrer noopener">pet food</a> must also be considered.&nbsp;



This focus on pet diets stems from the fact that companion animals - dogs and cats in particular - often consume meat-based products comparable to those eaten by humans, ultimately contributing to greenhouse gas emissions and land use changes. 



The question arises: should our pets join us in transitioning to plant-based diets?



<h2 class="wp-block-heading" id="h-the-environmental-costs-of-pet-diets">The environmental costs of pet diets</h2>



Quantifying how pet food affects the environment has long been hindered by sparse data on its ingredients. However, a 2020 report providing in-depth information on over 500 components used by the U.S. pet food industry enabled researchers to estimate its ecological footprint.&nbsp;



By examining this database, scientists calculated potential benefits if the global population of dogs and cats were fed <a href="https://www.earth.com/news/what-you-eat-can-literally-change-the-world/" target="_blank" rel="noreferrer noopener">plant-based diets</a>.



The results proved eye-opening. Transitioning all pet dogs to nutritionally sound plant-based diets could save an estimated 0.57 gigatons of CO₂ each year - more than what the United Kingdom emitted in 2023.&nbsp;



This transition would also free up land larger than Mexico’s total area, which could be reclaimed for habitat restoration, enhancing both biodiversity and carbon storage.&nbsp;



Furthermore, replacing livestock feed crops with plant-based alternatives for pets would yield enough calories to feed some 450 million people - more than the population of the European Union. Such a change could also spare as many as six billion land animals from slaughter annually.



A similar pattern emerges for <a href="https://www.earth.com/news/switching-dogs-and-cats-to-vegan-diets-would-help-the-earth-tremendously/" target="_blank" rel="noreferrer noopener">cats</a>. Switching all cats to plant-based diets could prevent 0.09 gigatons of CO₂ emissions yearly - surpassing New Zealand’s total emissions - and would liberate land exceeding the size of Germany.&nbsp;



The freed-up food energy could feed around 70 million people, comparable to the entire population of the United Kingdom.



<h2 class="wp-block-heading" id="h-rethinking-the-use-of-byproducts">Rethinking the use of byproducts</h2>



Some have assumed that pet food’s reliance on byproducts of human meat consumption reduces its environmental impact, on the grounds that these are materials otherwise considered waste.&nbsp;



However, recent research suggests the situation is more complicated. Because a relatively small portion of each animal carcass is converted into these byproducts, sustaining pet food production can, in fact, raise the demand for livestock overall.&nbsp;



More animals being raised and slaughtered translates into more land cleared for grazing or feed crops, heavier freshwater consumption, and additional greenhouse gas emissions.



<h2 class="wp-block-heading" id="h-health-implications-of-vegan-pet-diets">Health implications of vegan pet diets</h2>



While dogs are naturally omnivorous and cats are considered carnivorous, modern commercial pet foods already deviate from their ancestral diets.&nbsp;



In practice, these foods commonly blend plant materials - like grains and vegetables - with various animal-sourced ingredients, then add preservatives and flavor enhancers.&nbsp;



Meeting a pet’s nutritional needs fundamentally involves supplying adequate protein, amino acids, vitamins, and minerals, rather than providing specific meat sources. As researchers have found, pets can thrive on meticulously formulated plant-based diets.



Several studies completed by late 2024 suggest dogs and cats can thrive on vegan meals. In certain cases, these diets may lead to improvements in areas such as obesity control and allergic responses.&nbsp;



Furthermore, investigations into feeding behavior indicate that pets generally accept vegan meals as readily as they do meat-based ones, based on measures of excitement and enjoyment.



<h2 class="wp-block-heading" id="h-a-broader-push-for-sustainability">A broader push for sustainability</h2>



Confronting climate change and curbing biodiversity loss requires far-reaching measures, as emphasized by international bodies.&nbsp;



While shifting human diets toward plant-based options is a commonly proposed solution, it may not go far enough on its own.&nbsp;



Integrating pets into these changes expands the potential for lowering <a href="https://www.earth.com/news/greenhouse-gas-emissions-reach-another-all-time-high/" target="_blank" rel="noreferrer noopener">greenhouse gas emissions</a> and decreasing the strain on resources. If such diets are provided by reputable manufacturers that ensure complete nutrition, it is possible to preserve the health and welfare of companion animals.



For those contemplating this shift, websites like <a href="http://sustainablepetfood.info/" target="_blank" rel="noreferrer noopener">SustainablePetFood.info</a> can offer guidance in sourcing products that meet pets’ nutritional requirements.&nbsp;



By rethinking how companion animals are fed, pet owners can contribute to mitigating climate change while continuing to support the well-being of dogs and cats.&nbsp;



This aspect of dietary transition underscores that addressing global environmental challenges can be an inclusive effort, embracing not only human choices but also those made on behalf of the animals in our care.



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Changing how we feed our pets will improve their health and the environment

The global livestock industry plays a significant role in the...

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Today&#8217;s Video of the Day from the <a href="https://www.esa.int/">European Space Agency.</a> describes the effects of rising sea levels on the planet&#8217;s coastlines. 
Climate change is forcing ocean levels to fluctuate, rising in some regions while falling in others.
Satellite measurements over the last 25 years show that the sea-level is rising on average, and this rate of change is accelerating by around 3 millimeters a year.
Many low-lying countries such as the Netherlands are constantly threatened with tidal surges and flooding.
&#8212;
By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer 
Video Credit: European Space Agency

Sea-level rise is transforming the planet's coastlines