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



<p>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;</p>



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



<p>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.</p>



<p>“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;</p>



<p>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>.</p>



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



<p>“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,” said ESA.</p>



<p>“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;</p>



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



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



<p>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.</p>



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



<p>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.</p>



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



<p>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.</p>



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



<p>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.</p>



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



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



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



<p>“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;</p>



<p>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;</p>



<p>“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.”</p>



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



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



<p>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. </p>



<p>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.</p>



<p>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.</p>



<p>Image Credit: NASA/ESA/CSA James Webb Space Telescope</p>



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Dwarf galaxy provides a window into the early universe

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

<p>Today's Image of the Day from the European Space Agency features a pair of interacting spiral galaxies known as the Antennae Galaxies. They are located approximately 45 million light-years away in the constellation Corvus.&nbsp;</p>



<h2 class="wp-block-heading" id="h-antennae-galaxies-in-a-deadly-embrace">Antennae Galaxies in a deadly embrace </h2>



<p>“The NASA/ESA Hubble Space Telescope has snapped the best ever image of the Antennae Galaxies. Hubble has released images of these stunning galaxies twice before, once using observations from its Wide Field and Planetary Camera 2 (WFPC2) in 1997, and again in 2006 from the Advanced Camera for Surveys (ACS),” noted <a href="https://esahubble.org/images/potw1345a/" target="_blank" rel="noreferrer noopener">ESA</a>.</p>



<p>“The galaxies - also known as NGC 4038 and NGC 4039 - are locked in a deadly embrace. Once normal, sedate spiral galaxies like the Milky Way, the pair have spent the past few hundred million years sparring with one another.”</p>



<p>According to ESA, the clash of the Antennae Galaxies is so violent that stars have been ripped from their host <a href="https://www.earth.com/news/galaxy-collision-2-million-mph-stephans-quintet-captured-unprecedented-detail/" target="_blank" rel="noreferrer noopener">galaxies</a> to form a streaming arc between the two.&nbsp;</p>



<p>The name of the galaxy pair comes from this long stream of stars and gas, which resembles insect antennae.</p>



<h2 class="wp-block-heading" id="h-intense-bursts-of-star-formation-nbsp">Intense bursts of star formation&nbsp;</h2>



<p>The collision has triggered intense bursts of star formation, making the Antennae Galaxies one of the nearest and most dramatic examples of a starburst galaxy.&nbsp;</p>



<p>Many of the newly formed stars are concentrated in massive star clusters, some of which are expected to evolve into globular clusters over millions of years.</p>



<p>“This new image of the Antennae Galaxies shows obvious signs of chaos. Clouds of gas are seen in bright pink and red, surrounding the bright flashes of blue star-forming regions - some of which are partially obscured by dark patches of dust,” explained ESA.</p>



<p>“The rate of star formation is so high that the Antennae Galaxies are said to be in a state of starburst, a period in which all of the gas within the galaxies is being used to form stars.”&nbsp;</p>



<p>“This cannot last forever and neither can the separate galaxies; eventually the nuclei will coalesce, and the galaxies will begin their retirement together as one large elliptical galaxy.”</p>



<h2 class="wp-block-heading" id="h-significance-of-the-antennae-galaxies">Significance of the Antennae Galaxies</h2>



<p>The Antennae Galaxies are one of the most well-studied examples of galaxy collisions - offering insight into the processes that shape galaxies over time.</p>



<p>Astronomers study the Antennae Galaxies using a range of telescopes across different wavelengths, including visible light, infrared, and X-rays.&nbsp;</p>



<p>Observations in X-rays have revealed evidence of supernovae and <a href="https://www.earth.com/news/black-holes-may-talk-to-galaxies-through-energetic-winds/" target="_blank" rel="noreferrer noopener">black holes</a>, while infrared studies highlight regions of dust and star formation.&nbsp;</p>



<h2 class="wp-block-heading" id="h-the-milky-way-s-collision-course-nbsp">The Milky Way's collision course&nbsp;</h2>



<p>The Antennae Galaxies provide a glimpse into the future of our <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>, which is expected to eventually merge with the Andromeda Galaxy - our closest spiral galaxy neighbor.</p>



<p>The cosmic collision course of the Milky Way and Andromeda will reshape both galaxies over billions of years.&nbsp;</p>



<p>This event is expected to occur in about 4.5 billion years. Both galaxies are part of the Local Group, a cluster of galaxies bound together by gravity. Their mutual gravitational pull is drawing them closer at a speed of approximately 110 kilometers per second.</p>



<h2 class="wp-block-heading" id="h-the-birth-of-an-elliptical-galaxy-nbsp">The birth of an elliptical galaxy&nbsp;</h2>



<p>When the two galaxies collide, their individual stars will largely avoid direct collisions due to the vast distances between them. However, the gravitational forces involved will create dramatic effects.&nbsp;</p>



<p>These forces will distort the galaxies' <a href="https://www.earth.com/news/shapes-of-one-million-galaxies-hint-at-the-universes-origins/" target="_blank" rel="noreferrer noopener">shapes</a>, triggering intense bursts of star formation as gas clouds collide and compress. Over time, the galaxies will settle into a new, larger elliptical galaxy often referred to as "Milkomeda" or "Milkdromeda" by astronomers.</p>



<h2 class="wp-block-heading" id="h-galaxy-merger-and-the-solar-system">Galaxy merger and the solar system</h2>



<p>Despite the seemingly destructive nature of the collision, the solar system is unlikely to face direct harm. Our Sun may find itself flung into a new orbit within the merged galaxy or even cast into intergalactic space.&nbsp;</p>



<p>The merger will also significantly alter the night sky, with the Andromeda Galaxy becoming increasingly prominent before blending into the unified structure.</p>



<p>This event is part of the natural <a href="https://www.earth.com/news/galaxies-are-much-bigger-than-we-originally-believed-gas-clouds/" target="_blank" rel="noreferrer noopener">evolution of galaxies</a> and serves as a fascinating reminder of the dynamic and ever-changing nature of the universe. </p>



<p>While the collision is still billions of years away, studying it helps astronomers understand galactic interactions and the long-term future of our cosmic neighborhood.</p>



<p>Image Credit<strong>: </strong>ESA/Hubble &amp; NASA</p>



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Violent clash of the Antennae Galaxies  

<p>Today's Image of the Day from the European Space Agency features the galaxy NGC 2090, located approximately 40 million light-years away in the constellation Columba.</p>



<p>NGC 2090 is a stunning spiral galaxy that is notable for its well-defined structure, featuring a bright central core surrounded by tightly wound spiral arms.&nbsp;</p>



<p>These arms are filled with young, hot stars and interstellar gas, indicating active star formation.&nbsp;</p>



<p>Captured by the Webb Telescope’s MIRI and NIRCam instruments, the image reveals the galaxy's winding spiral arms and the swirling gas and dust of its disc in magnificent and unique detail, noted <a href="https://www.esa.int/ESA_Multimedia/Images" target="_blank" rel="noreferrer noopener">ESA</a>. </p>



<h2 class="wp-block-heading" id="h-observations-of-ngc-2090">Observations of NGC 2090</h2>



<p>The galaxy’s spiral pattern is relatively symmetrical, making it a fascinating object of study for astronomers interested in galactic evolution and dynamics.&nbsp;</p>



<p>Observations of NGC 2090, including those conducted by the <a href="https://www.earth.com/news/hubble-helps-solve-the-mystery-of-a-young-eruptive-star/" target="_blank" rel="noreferrer noopener">Hubble</a> Space Telescope, have provided valuable insights into the properties of its stellar populations, gas content, and the nature of its spiral structure.</p>



<p>“NGC 2090 was one of many galaxies studied by the NASA/ESA Hubble Space Telescope to refine the measurement of the Universe’s expansion rate, or ‘Hubble constant,’” said ESA.&nbsp;</p>



<p>“This can be done by observing a special type of variable stars named ‘Cepheids’ in relatively nearby galaxies.”</p>



<h2 class="wp-block-heading" id="h-new-insights-into-ngc-2090">New insights into NGC 2090</h2>



<p>A Cepheid-based measurement from 1998 indicated that NGC 2090 is 37 million light-years away from Earth. However, the latest measurements suggest that the galaxy is 40 million light-years away.</p>



<p>“Already before that Hubble project in 1998, NGC 2090 had been well studied as a very prominent nearby example of star formation,” noted ESA.&nbsp;</p>



<p>“Described as a ‘flocculent’ spiral, this galaxy has a patchy, dusty disc and arms that are flaky or not visible at all. We can see those patterns well in Hubble's visible-light images. However, Webb’s NIRCam near-infrared data reveal the spiral arms with remarkable clarity.”&nbsp;</p>



<h2 class="wp-block-heading" id="h-what-are-spiral-galaxies">What are spiral galaxies?</h2>



<p><a href="https://www.earth.com/news/the-mesmerizing-beauty-of-spiral-galaxies/" target="_blank" rel="noreferrer noopener">Spiral galaxies</a> are among the most common and visually striking types of galaxies in the universe.&nbsp;</p>



<p>They are characterized by their flat, disk-like shape with a bright central bulge surrounded by sweeping spiral arms.&nbsp;</p>



<h3 class="wp-block-heading" id="h-spiral-arms-and-central-bulge-nbsp">Spiral arms and central bulge&nbsp;</h3>



<p>The arms of a spiral galaxy are regions where stars, gas, and dust are concentrated, often glowing brightly with the light of young, hot stars that form within them.&nbsp;</p>



<p>The central bulge typically contains older stars and can host a supermassive black hole at its core.&nbsp;</p>



<h3 class="wp-block-heading" id="h-types-of-spiral-galaxies-nbsp">Types of spiral galaxies&nbsp;</h3>



<p>Spiral galaxies are classified into different types based on how tightly their arms are wound and the size of their central bulge, ranging from tightly wound "Sa" galaxies to loosely wound "Sc" types.</p>



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



<p>The structure of spiral galaxies is maintained by the interplay of gravity and angular momentum, with a rotating disk of stars and gas giving rise to their iconic shape.&nbsp;</p>



<p>They are active sites of <a href="https://www.earth.com/news/massive-star-redefines-our-understanding-of-stellar-evolution/" target="_blank" rel="noreferrer noopener">star formation</a> due to the abundance of gas in their arms.&nbsp;</p>



<p>Spiral galaxies often have a halo of older stars and globular clusters surrounding their disks, which provides clues about their formation and evolution.&nbsp;</p>



<h3 class="wp-block-heading" id="h-barred-spiral-galaxy">Barred spiral galaxy</h3>



<p>The <a href="https://www.earth.com/news/milky-way-galaxy-is-surrounded-by-massive-magnetic-fields/" target="_blank" rel="noreferrer noopener">Milky Way</a>, the galaxy that contains our Solar System, is a prime example of a barred spiral galaxy, a subtype where a bar-shaped structure of stars extends from the central bulge.&nbsp;</p>



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



<p>Columba is a small and relatively faint constellation in the southern sky, whose name means "dove" in Latin. It was introduced in the late 16th century by the Dutch astronomer Petrus Plancius and first appeared in a celestial atlas by Johann Bayer in 1603.&nbsp;</p>



<p>The <a href="https://www.earth.com/news/super-jupiter-discovered-in-the-great-bear-constellation/" target="_blank" rel="noreferrer noopener">constellation</a> is said to represent the dove sent out by Noah during the biblical flood, tying it to themes of hope and peace.</p>



<p>Columba lies near the larger constellation Canis Major and is bordered by others such as Lepus and Puppis.&nbsp;</p>



<p>Although it lacks particularly bright stars, its most notable star, Alpha Columbae (also called Phact), shines at a magnitude of approximately 2.6 and is a hot blue-white star. Beta Columbae, another prominent star in the constellation, is a slightly cooler, yellow-white star.</p>



<p>The constellation is best viewed from the Southern Hemisphere during the summer months, though it can also be seen from lower latitudes in the Northern Hemisphere.&nbsp;</p>



<p>Image Credit: NASA/ESA/CSA James Webb Space Telescope&nbsp;</p>



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Webb unveils a spiral galaxy in magnificent detail

<p>Today's <strong>Image of the Day</strong> 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;</p>



<p>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;</p>



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



<p>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;</p>



<p>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.</p>



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



<p>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.&nbsp;</p>



<p><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.</p>



<p>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;</p>



<p>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.</p>



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



<p>Additionally, Euclid's dataset will help scientists identify clusters of old stars (globular clusters) and discover new dwarf galaxies around NGC 6744. </p>



<p>Remarkably, Euclid has already identified a new dwarf satellite galaxy of NGC 6744 - a surprising discovery given that the galaxy has been studied extensively.</p>



<p>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>.</p>



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



<p>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;</p>



<p>The spiral arms of NGC 6744 are well-defined and extend outward, wrapping around the central bar. </p>



<p>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. </p>



<h2 class="wp-block-heading" id="h-types-of-spiral-galaxies">Types of spiral galaxies</h2>



<p><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;</p>



<p>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;</p>



<p>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;</p>



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



<p>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.</p>



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



<p>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. </p>



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



<p>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.</p>



<p>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.</p>



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



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Young stars illuminate a spiral galaxy in the constellation Pavo

<p>Today's <strong>Image of the Day</strong> from the European Space Agency features the Columbia Glacier, a tidewater glacier located in Prince William Sound on the south coast of Alaska.</p>



<p>The Columba Glacier is one of the most rapidly changing <a href="https://www.earth.com/news/melting-glaciers-pose-great-threat-to-biodiversity-in-mountain-ranges/" target="_blank" rel="noreferrer noopener">glaciers</a> in the world and has been closely studied for the insights it provides into glacial mechanics and climate change impacts. </p>



<p>"Since the early 1980s, the Columbia Glacier has retreated more than 20 km and lost about half of its total volume. This one glacier accounts for nearly half of the ice lost in the Chugach Mountains," noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.</p>



<p>"The changing climate is thought to have caused its retreat. Until 1980, when its rapid and constant retreat began, the glacier’s terminus was observed at the northern edge of Heather Island, which lies near the end of Columbia Bay, the inlet into which the glacier currently flows before draining into Prince William Sound."</p>



<p>ESA noted that this satellite image, captured in September of 2023, reveals a mostly ice-free Columbia Bay dotted with numerous icebergs and fragmented sea-ice.</p>



<h2 class="wp-block-heading" id="h-dramatic-calving-events">Dramatic calving events</h2>



<p>The Columbia Glacier is known for its dramatic calving events, where large chunks of ice break off from the glacier's terminus and fall into the sea, becoming icebergs.</p>



<p>This process has been particularly active as the glacier has retreated, contributing to hazards for shipping in Prince William Sound.</p>



<p>The glacier has been the focus of extensive scientific research, serving as a case study for understanding the dynamics of tidewater glaciers and their responses to <a href="https://www.earth.com/news/preparing-for-ocean-acidification-a-silent-killer-of-climate-change/" target="_blank" rel="noreferrer noopener">climate change</a>. Studies have used satellite imagery, field observations, and modeling to track its changes over time.</p>



<h2 class="wp-block-heading" id="h-climate-impacts-on-the-columbia-glacier">Climate impacts on the Columbia Glacier</h2>



<p>"Columbia is just one of the many glaciers suffering from the effects of climate change. Most of the glaciers around the world are losing mass," said ESA.</p>



<p>"However, before the advent of satellites, measuring their retreat and studying their vulnerability to climate change was difficult considering their size, remoteness and rugged terrain they occupy."</p>



<p>Now, noted ESA, different satellite instruments are available to gather information systematically and over large areas, providing an effective means to monitor change, keep track of all calving stages, and quantify the melting rate.</p>



<h2 class="wp-block-heading" id="h-climate-change-and-columbia-s-retreat-nbsp">Climate change and Columbia's retreat&nbsp;</h2>



<p>Columbia Glacier flows from the Chugach Mountains into Columbia Bay. It was once one of the largest contributors to <a href="https://www.earth.com/news/sea-level-rise-will-cost-coastal-cities-over-1-trillion-in-damages/" target="_blank" rel="noreferrer noopener">sea level rise</a> due to its significant ice loss.&nbsp;</p>



<p>The glacier's dynamics are influenced by its interaction with water, where the terminus meets the ocean. As the glacier flows into the sea, large chunks of ice calve off the front, leading to dramatic scenes of ice crashing into the <a href="https://www.earth.com/news/shelf-sediment-ocean-composition/" target="_blank" rel="noreferrer noopener">ocean</a>. </p>



<p>This process has been intensifying due to warmer temperatures and changes in water circulation, which undermine the ice from below.</p>



<p>Columbia Glacier's retreat has significant implications for marine navigation and local ecosystems. The increase in icebergs calving into the bay poses hazards to ships, while the fresh meltwater impacts local water temperatures and salinity, affecting the habitat of fish and other marine life.</p>



<h2 class="wp-block-heading" id="h-melting-glaciers-in-a-warming-climate">Melting glaciers in a warming climate </h2>



<p>Glaciers, which are large masses of accumulated snow and ice, store about 69 percent of the world's freshwater. As the climate warms, these glaciers increasingly melt and release freshwater into nearby seas and the ocean at large.</p>



<h3 class="wp-block-heading" id="h-influx-of-freshwater">Influx of freshwater</h3>



<p>The influx of freshwater from <a href="https://www.earth.com/news/melting-glaciers-pose-great-threat-to-biodiversity-in-mountain-ranges/" target="_blank" rel="noreferrer noopener">melting glaciers</a> alters the salinity (salt concentration) of the ocean water. Since freshwater is less dense than saltwater, its addition can lead to stratification in which lighter, less salty water layers on top of denser, saltier water.&nbsp;</p>



<p>Stratification can disrupt ocean currents, which are driven in part by differences in water density and temperature. These currents are crucial for regulating global climate by distributing heat and nutrients around the planet.</p>



<h3 class="wp-block-heading" id="h-changes-in-salinity-nbsp">Changes in salinity&nbsp;</h3>



<p>Furthermore, changes in <a href="https://www.earth.com/news/human-induced-changes-in-ocean-salinity-threaten-biodiversity-and-marine-ecosystems/" target="_blank" rel="noreferrer noopener">salinity</a> can affect marine life, which often has narrow salinity tolerance ranges. For example, shifts in salinity can impact breeding cycles, migration patterns, and the availability of nutrients.&nbsp;</p>



<h3 class="wp-block-heading" id="h-global-carbon-cycle">Global carbon cycle</h3>



<p>As the ocean's composition changes, its capacity to absorb carbon dioxide from the atmosphere could also be altered, affecting the global carbon cycle and, by extension, climate change feedback mechanisms.</p>



<p>The melting of glaciers contributes to more pronounced changes in ocean conditions, impacting everything from global climate systems to local ecosystems in marine environments.</p>



<p>Image Credit: ESA&nbsp;</p>



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Columbia Glacier on the south coast of Alaska

<p>Why do some individuals rush to help, while others hesitate? A new study led by Dr. Inbal Bartal of Tel Aviv University digs deep into this question using rats. The findings highlight the strong influence of social experience and brain chemistry on prosocial behavior and willingness to help.</p>



<p>The team used a helping behavior task where rats could free a distressed peer trapped in a restrainer. Rats that had previous positive interactions were more likely to help. </p>



<p>These "helper rats" also showed more brain <a href="https://www.earth.com/news/sleep-increases-feelings-of-hope-happiness-and-gratitude/" target="_blank" rel="noreferrer noopener">activity</a> in areas linked to empathy and motivation compared to their less helpful counterparts.</p>



<h2 class="wp-block-heading" id="h-social-bonds-drive-helping">Social bonds drive helping </h2>



<p>Helper rats exhibited stronger activation in the anterior cingulate cortex, somatosensory cortex, and other empathy-related areas. This activity pattern suggests that not just feeling another’s distress, but having a social bond, is crucial for helping.</p>



<p>Interestingly, oxytocin - the hormone involved in bonding - played a key role. Rats that consistently helped had higher oxytocin receptor expression in the nucleus accumbens, a major reward center in the brain. </p>



<p>Blocking oxytocin signaling did not completely erase helping <a href="https://www.earth.com/news/who-is-happier-being-single-men-or-women/" target="_blank" rel="noreferrer noopener">behavior</a> but did reduce the rats’ social tendencies. According to the researchers, caring about others appears more important than simply sensing their distress.</p>



<p>“We appear to live in an increasingly polarized society where there is a gap in empathy towards others," said Dr. Bartal, a faculty member in the Psychology Department and School of Neuroscience at <a href="http://tau.ac.il/" target="_blank" rel="noreferrer noopener">Tel-Aviv University</a>.</p>



<p>"This work helps us understand prosocial, or helpful, acts better. We see others in distress all the time but tend to help only certain individuals. The similarity between human and rat brains helps us understand the way our brain mediates prosocial decisions."</p>



<h2 class="wp-block-heading" id="h-helpful-rats-socialize-more">Helpful rats socialize more</h2>



<p>The study found that rats who became "helpers" showed greater <a href="https://www.earth.com/news/facial-expressions-arent-enough-to-understand-human-emotions/" target="_blank" rel="noreferrer noopener">social</a> affiliation even before the helping task began. Before any rat was trapped, these rats spent more time interacting, lying together, and engaging in affiliative behaviors with their cagemates.</p>



<p>The frequency of social interactions predicted how quickly rats would later act to free a distressed peer. Rats that interacted more often on the first day were faster to help across testing days. </p>



<p>This link between early social behavior and later helping actions offers new insights into how prosocial tendencies develop.</p>



<h2 class="wp-block-heading" id="h-helpers-had-more-oxytocin-receptors">Helpers had more oxytocin receptors</h2>



<p>Gene expression studies revealed that helper rats had significantly higher oxytocin receptor (Oxtr) levels specifically in the nucleus accumbens. They also showed greater activity of genes related to social reward and emotional <a href="https://www.earth.com/news/coping-with-eco-anxiety-turning-climate-worry-into-action/" target="_blank" rel="noreferrer noopener">regulation</a>.</p>



<p>Importantly, genes tied to stress responses were downregulated in helper rats. This suggests that lower stress reactivity could promote a readiness to help others. Brain-wide analyses also showed that helper rats had more active networks in sensory and empathy-related brain regions.</p>



<p>When the researchers blocked oxytocin signaling in the brain’s paraventricular nucleus, rats showed fewer social behaviors. This reduced sociality hints that oxytocin may strengthen social bonds in the brain, which in turn could drive helping actions.</p>



<h2 class="wp-block-heading" id="h-social-brains-are-motivated-to-help">Social brains are motivated to help</h2>



<p>Helper rats demonstrated a widespread activation of the brain’s prosocial network. Critical areas included the anterior cingulate cortex, orbitofrontal cortex, nucleus accumbens, and insular cortex. Many of these regions overlap with known human empathy and reward circuits.</p>



<p>Moreover, the orbitofrontal cortex stood out as playing a major role. This area, known for evaluating rewards and decisions, showed the strongest difference between helpers and non-helpers.</p>



<p>Social interaction frequency correlated strongly with brain activity in these regions. Rats who were more socially engaged early on had higher brain activation related to empathy later, even days after initial testing.</p>



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



<p>The research suggests that social connectedness and neurochemical factors together shape helping behavior. The results support the idea that empathy alone does not always lead to action - social bonds and emotional rewards are key motivators.</p>



<p>Understanding how oxytocin and social affiliation drive prosocial behavior could help us better support empathy in increasingly divided societies. Strengthening social bonds might be more effective than simply raising awareness about others' distress.</p>



<p>Dr. Bartal and colleagues have illuminated the biological roots of kindness in a way that could one day inform how we nurture empathy in humans.</p>



<p>The study is published in the <em><a href="https://www.jneurosci.org/content/early/2025/04/17/JNEUROSCI.0845-24.2025" target="_blank" rel="noreferrer noopener">Journal of Neuroscience</a>.</em></p>



<p>-----</p>



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Acts of kindness: Social brains are wired to help

Why do some individuals rush to help, while others hesitate?...

Asteroid,Vesta,In,Space.,Surface,Of,Space,Stone,From,Asteroid

<p>For more than a decade, Vesta has sat in a scientific gray zone: too big and geologically complex to be an ordinary asteroid, yet never quite elevated to the status of a true planet. </p>



<p>Its basalt-covered surface hinted at a molten past, and early analyses of data from NASA’s Dawn spacecraft suggested that Vesta possessed the same fundamental architecture as Earth - crust, mantle, and metallic core. That tidy picture has now been upended.</p>



<h2 class="wp-block-heading" id="h-vesta-s-internal-structure">Vesta's internal structure </h2>



<p>A new study led by the <a href="https://www.jpl.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA Jet Propulsion Laboratory</a> (JPL) re-examined Dawn’s gravity and imaging records with greatly refined calibration methods. The result is a radical reinterpretation of Vesta’s internal <a href="https://www.earth.com/news/asteroid-vesta-found-to-have-channels-that-look-like-water-made-gullies/" target="_blank" rel="noreferrer noopener">structure</a>.</p>



<p>Rather than harboring a dense central core, the 500-kilometer-wide body appears almost uniform throughout. </p>



<p>“The lack of a core was very surprising. It’s a really different way of thinking about Vesta," said study co-author Seth Jacobson, a planetary scientist at <a href="https://msu.edu/" target="_blank" rel="noreferrer noopener">Michigan State University</a>.</p>



<h2 class="wp-block-heading" id="h-vesta-s-history-is-surprisingly-complex">Vesta's history is surprisingly complex</h2>



<p>The research team reached this conclusion by looking at a property called the moment of inertia, which governs how an object’s mass is distributed and, consequently, how it spins in space. </p>



<p>Bodies with heavy centers behave like figure skaters who pull their arms in to rotate faster; those with evenly distributed mass spin more sluggishly. Vesta’s spin signature fits the latter description, contradicting earlier models that required a substantial iron-nickel core.</p>



<p>To obtain their revised measurements, principal investigator Ryan Park and colleagues spent nearly a decade perfecting the cross-calibration between Dawn’s onboard cameras and radio-tracking data transmitted through <a href="https://www.nasa.gov/communicating-with-missions/dsn/" target="_blank" rel="noreferrer noopener">NASA’s Deep Space Network</a>.</p>



<p>“After nearly a decade of refining our calibration and processing techniques, we achieved remarkable alignment between Dawn’s Deep Space Network radiometric data and onboard imaging data,” Park explained. </p>



<p>“Our findings show Vesta’s history is far more complex than previously believed, shaped by unique processes like interrupted planetary differentiation and late-stage collisions.”</p>



<h2 class="wp-block-heading" id="h-two-competing-theories-on-vesta">Two competing theories on Vesta</h2>



<p>Two competing ideas now vie to explain what Vesta really is. One option is that the object began to differentiate - melting internally so that metals could sink and silicates rise - but the process froze in mid-stride. </p>



<p>That would make Vesta a kind of geological time capsule, preserving a rare snapshot of <a href="https://www.earth.com/news/scorching-world-offers-clues-to-planetary-evolution/" target="_blank" rel="noreferrer noopener">planetary evolution</a> arrested before its final act.</p>



<p>Yet this scenario clashes with laboratory analyses of meteorites that match Vesta’s spectral fingerprint. “We’re really confident these meteorites came from Vesta,” Jacobson noted. “And these don’t show obvious evidence of incomplete differentiation.”</p>



<h2 class="wp-block-heading" id="h-fragment-of-a-lost-world">Fragment of a lost world</h2>



<p>The alternative, more audacious hypothesis is that Vesta is not a stalled planet at all but a fragment blasted off a larger world during the <a href="https://www.earth.com/news/distant-icy-worlds-are-unlocking-secrets-of-the-solar-system/" target="_blank" rel="noreferrer noopener">solar system</a>’s chaotic youth. Jacobson first floated the idea informally years ago, suggesting that some meteorites might be relics of violent impacts among embryonic planets.</p>



<p>“This idea went from a somewhat silly suggestion to a hypothesis that we’re now taking seriously due to this re-analysis of NASA Dawn mission data,” Jacobson said. </p>



<p>If correct, Vesta would be a shard of primordial crust from a planet that continued to accrete elsewhere - or perhaps never reached maturity because subsequent collisions shattered it beyond recognition.</p>



<h2 class="wp-block-heading" id="h-broader-implications-of-the-study">Broader implications of the study</h2>



<p>Either explanation reshapes Vesta’s scientific value. In the incomplete-differentiation model, the body offers insight into the thermal limits that determine whether small planetary embryos grow full cores. </p>



<p>In the impact-fragment model, Vesta becomes forensic evidence of the collisions that sculpted the inner solar system, possibly preserving geochemical clues to an unknown “parent” planet. </p>



<p>Jacobson’s research group is already building computer models of such giant impacts, while graduate student Emily Elizondo examines how ejected debris might migrate into the asteroid belt and survive for billions of years.</p>



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



<p>More work lies ahead. Planetary <a href="https://www.earth.com/news/chemists-could-be-key-to-prevent-animal-extinction/" target="_blank" rel="noreferrer noopener">chemists</a> can re-evaluate Vesta-derived <a href="https://www.earth.com/news/what-meteorites-tell-us-about-their-birthplace-in-space/" target="_blank" rel="noreferrer noopener">meteorites</a> in light of the new gravity data, looking for isotopic markers that would either support or refute a uniform interior.</p>



<p>Meanwhile, improved dynamical simulations could test whether a collision-origin scenario can reproduce Vesta’s current orbit and composition. </p>



<p>Dawn’s legacy data set remains a treasure trove; the same re-processing techniques may yet reveal subtler interior details or reconcile inconsistencies in previous models.</p>



<h2 class="wp-block-heading" id="h-pieces-of-an-ancient-planet">Pieces of an ancient planet</h2>



<p>Whatever the final answer, Vesta’s story now looks less like a straightforward tale of arrested growth and more like a detective mystery spanning 4.5 billion years. “No longer is the Vesta meteorite collection a sample of a body in space that failed to make it as a planet,” Jacobson said.</p>



<p>“These could be pieces of an ancient planet before it grew to full completion. We just don’t know which planet that is yet.” </p>



<p>In reframing Vesta from wannabe planet to either an unfinished embryo or a planetary shard, scientists gain fresh perspective on the tumultuous processes that forged the terrestrial world we inhabit today.</p>



<p>The study is published in the journal <a href="https://www.nature.com/articles/s41550-025-02533-7" target="_blank" rel="noreferrer noopener"><em>Nature Astronomy</em></a></p>



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Asteroid Vesta may be a fragment of a lost world

For more than a decade, Vesta has sat in a...

<p>As the global community scrambles to limit warming, a new study offers an unexpected possibility: we may not need to wait for advanced aircraft technology to intervene in cooling Earth’s climate.</p>



<p>In the face of growing concerns over climate tipping points and the slow pace of emissions cuts, some scientists have turned their attention to solar geo-engineering. This approach involves reflecting a portion of the Sun’s energy back into space to cool the planet.</p>



<h2 class="wp-block-heading" id="h-specialized-aircraft-may-not-be-necessary">Specialized aircraft may not be necessary </h2>



<p>One proposed method is stratospheric aerosol injection (SAI), where sulphur dioxide is released into the upper atmosphere. There, it forms reflective particles that scatter sunlight and reduce global temperatures. </p>



<p>Until now, most models and <a href="https://www.earth.com/news/solar-geoengineering-could-save-up-to-400000-lives-each-year/" target="_blank" rel="noreferrer noopener">strategies</a> focused on injecting these particles high above the tropics - 20 kilometers or more - requiring specialized aircraft not yet in existence.</p>



<p>However, new research led by University College London (UCL) suggests a different, perhaps more accessible path: use commercial aircraft to inject particles at lower altitudes over the polar regions.</p>



<h2 class="wp-block-heading" id="h-cooling-earth-with-commercial-aircraft">Cooling Earth with commercial aircraft </h2>



<p>In the new study, the research team used 41 computer simulations with the UK Earth System Model to explore the effects of SAI at various altitudes, latitudes, and seasons.</p>



<p>The results showed that even at 13 kilometers (about 8 miles) - within reach of existing planes like the Boeing 777F - SAI could still cool the planet, though less efficiently than tropical high-altitude deployments.</p>



<p>“Solar <a href="https://www.earth.com/news/we-are-changing-the-clouds-unintended-geoengineering-test-atlantic-warming/" target="_blank" rel="noreferrer noopener">geoengineering</a> comes with serious risks and much more research is needed to understand its impacts. However, our study suggests that it is easier to cool the planet with this particular intervention than we thought," noted lead author Alistair Duffey, a PhD student at <a href="https://www.ucl.ac.uk" target="_blank" rel="noreferrer noopener">UCL</a>.</p>



<p>"This has implications for how quickly stratospheric aerosol injection could be started and by who."</p>



<p>This approach would use lower altitudes over the poles because the stratosphere sits closer to the surface there. While the strategy achieves only about 35% of the forcing efficiency of traditional high-altitude methods, it still results in meaningful cooling and avoids the decade-long wait to develop custom aircraft.</p>



<h2 class="wp-block-heading" id="h-how-polar-injection-works">How polar injection works</h2>



<p>To reflect enough sunlight, aerosols must remain in the stratosphere where they are dry and stable, free from clouds that wash particles away. </p>



<p>The tropopause - the boundary between the troposphere and stratosphere - is lower at the poles. That allows existing jets to reach the stratosphere more easily at high latitudes than at the equator.</p>



<p>The simulations show that injecting 12 million tonnes (about 13.2 million US tons) of sulphur dioxide per year at 13 kilometers (about 8 miles) above 60° North and South could cool the Earth by about 0.6°C (about 1.1°F).</p>



<p>This is comparable to the cooling observed after the Mount Pinatubo volcanic eruption in 1991, which had a significant but temporary impact on global temperatures.</p>



<p>However, at 13 kilometers, aerosols linger in the atmosphere for months rather than years. This means more frequent injections would be needed to sustain cooling. In comparison, particles released at 20 kilometers can persist much longer, providing greater efficiency for the same mass of injected <a href="https://www.earth.com/news/should-we-risk-geoengineering-to-reverse-climate-change/" target="_blank" rel="noreferrer noopener">material</a>.</p>



<h2 class="wp-block-heading" id="h-the-timing-of-aircraft-injection">The timing of aircraft injection</h2>



<p>One of the most striking insights from the study is how the timing of aircraft injection matters for cooling Earth. Seasonal deployment, specifically during local spring and summer, improved both the conversion of sulphur dioxide into sulphuric acid and the lifetime of the particles.</p>



<p>These improvements occur because ultraviolet radiation - needed to drive chemical reactions - is more intense in the summer months, especially near the poles.</p>



<p>In fact, the study found that seasonal injection during spring and summer resulted in 39% more effective cooling than injecting year-round at the same altitude. This strategy produced more aerosol during the sunny months and avoided wasted effort during the dark polar winter, when particles would have little cooling effect.</p>



<p>The polar summer also reduces the longwave warming effect from larger particles, which tends to offset some of the cooling benefits of SAI. By optimizing timing, the low-altitude strategy compensates slightly for its reduced efficiency.</p>



<h2 class="wp-block-heading" id="h-benefits-of-using-commercial-aircraft">Benefits of using commercial aircraft</h2>



<p>Deploying SAI using existing jets offers one major benefit: speed. Designing, building, and certifying high-altitude aircraft could take a decade and billions of dollars. In contrast, modifying current commercial planes could begin in just a few years.</p>



<p>“Although pre-existing aircraft would still require a substantial modification program to be able to function as deployment tankers, this route would be much quicker than designing a novel high-flying aircraft,” noted study co-author Wake Smith, Lecturer at <a href="https://www.yale.edu" target="_blank" rel="noreferrer noopener">Yale University</a>.</p>



<p>The Boeing 777F, for example, could be adapted to carry and release sulphur dioxide at the necessary altitude. With a payload of over 100 tonnes (about 110 US tons) and an average of 5.7 flights per day, a fleet of 102 aircraft could deliver the required 21 million tonnes (about 23.1 million US tons) per year for 1°C (about 1.8°F) of cooling.</p>



<p>This would be more efficient than a larger fleet of smaller, custom-built high-altitude aircraft.</p>



<h2 class="wp-block-heading" id="h-practical-and-ethical-challenges-remain">Practical and ethical challenges remain</h2>



<p>Despite its potential, low-altitude polar SAI presents serious challenges. The efficiency trade-off means more sulphur dioxide must be injected to achieve the same temperature drop. That increases side effects such as acid rain, changes in ozone chemistry, and health impacts due to particle deposition.</p>



<p>Infrastructure also limits feasibility. While several northern airfields exist at high latitudes, options in the Southern Hemisphere are scarce. </p>



<p>For example, Ushuaia in Argentina is the southernmost large airport, but it handles fewer than ten flights a day. Major SAI operations would require new infrastructure in southern Patagonia or significant aircraft travel from lower latitudes, reducing efficiency and increasing costs.</p>



<p>Moreover, unequal <a href="https://www.earth.com/news/can-geoengineering-save-the-doomsday-glacier/" target="_blank" rel="noreferrer noopener">cooling</a> across the globe could worsen climate justice concerns. High-latitude injection cools the poles more effectively than the tropics. </p>



<p>That’s a problem because many of the world’s most vulnerable populations live in tropical regions, where the risks of heat, disease, and crop failure are already high.</p>



<h2 class="wp-block-heading" id="h-injections-won-t-replace-emissions-cuts">Injections won’t replace emissions cuts</h2>



<p>While low-altitude SAI could offer a stopgap solution, it does not eliminate the need to cut emissions. The researchers stress that this approach is not a replacement for long-term climate mitigation.</p>



<p>“Stratospheric aerosol injection is certainly not a replacement for greenhouse gas emission reductions as any potential negative side effects increase with the amount of cooling: we can only achieve long-term climate stability with net zero,” noted co-author Dr. Matthew Henry from the <a href="https://www.exeter.ac.uk/" target="_blank" rel="noreferrer noopener">University of Exeter</a>.</p>



<p>In addition to reducing emissions, any SAI strategy must roll out gradually to prevent sudden shifts in global temperatures. Abrupt cooling or rapid withdrawal could cause disruptions to agriculture, ecosystems, and human health. The risks of so-called “termination shock” remain a significant concern.</p>



<h2 class="wp-block-heading" id="h-looking-ahead-a-risky-opportunity">Looking ahead: A risky opportunity</h2>



<p>This study expands the boundaries of what might be possible in near-term geoengineering. It introduces a technically feasible strategy that could be deployed using planes that already exist. </p>



<p>However, the approach is far from optimal. It is less efficient, comes with greater side effects, and offers uneven global benefits.</p>



<p>Still, the idea of using current aircraft for cooling Earth - even if modestly - adds a new dimension to climate policy. It highlights the importance of further research, not just to confirm technical viability, but to understand the social, ethical, and environmental consequences.</p>



<p>Whether low-altitude SAI becomes part of the global climate toolkit depends on decisions yet to be made. But this study opens that conversation with clarity, urgency, and a firm grounding in data. </p>



<p>It calls on policymakers to weigh aircraft-based cooling options carefully, and on scientists to keep exploring the boundaries of what is possible.</p>



<p>The study is published in the journal <em><a href="https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2024EF005567" target="_blank" rel="noreferrer noopener">Earth's Future</a>.</em></p>



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Cooling Earth's climate with commercial aircraft may be possible

As the global community scrambles to limit warming, a new...


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