Today's Image of the Day from the European Space Agency (ESA) features the distant galaxy LEDA 22057, which is located about 650 million light-years away in the constellation Gemini. 



Within the galaxy lies a pale blue dot - SN 2024PI, a supernova explosion that was discovered by an automated survey in January 2024.



“The survey covers the entire northern half of the night sky every two days and has cataloged more than 10,000 supernovae,” noted <a href="https://www.esa.int/ESA_Multimedia/Images/2025/01/Pale_blue_supernova_dot" target="_blank" rel="noreferrer noopener">ESA</a>.



“The supernova is visible in this image: located just down and to the right of the galactic nucleus, the pale blue dot of SN 2024PI stands out against the galaxy’s ghostly spiral arms.”



<h2 class="wp-block-heading" id="h-remnants-of-a-supernova">Remnants of a supernova </h2>



ESA noted that the image was taken about a month and a half after the supernova was discovered, so it appears many times fainter than its <a href="https://www.earth.com/news/shockingly-bright-carbon-monoxide-detected-in-supernova-remnant/" target="_blank" rel="noreferrer noopener">maximum brilliance</a>.



“SN 2024PI is classified as a Type Ia supernova. This type of supernova requires a remarkable object called a white dwarf, the crystallized core of a star with a mass less than about eight times the mass of the Sun,” explained ESA.



“When a star of this size uses up the supply of hydrogen in its core, it balloons into a red giant, becoming cool, puffy and luminous. Over time, pulsations and stellar winds cause the star to shed its outer layers, leaving behind a white dwarf and a colorful planetary nebula.”&nbsp;



<h2 class="wp-block-heading" id="h-the-fate-of-white-dwarfs">The fate of white dwarfs</h2>



Most stars in the <a href="https://www.earth.com/news/stars-at-the-edge-of-our-milky-way-galaxy-travel-more-slowly/" target="_blank" rel="noreferrer noopener">Milky Way</a> will eventually transition to white dwarfs after their death. Whether or not a star becomes a white dwarf depends on its mass.&nbsp;



Stars that are significantly more massive will end their lives differently. Stars that exceed the critical mass threshold of eight times the Sun undergo more violent deaths.&nbsp;



After exhausting their nuclear fuel, they collapse under their immense gravity and trigger a supernova explosion. Depending on the remaining core mass, they may leave behind either a neutron star or a black hole, rather than a <a href="https://www.earth.com/news/hungry-white-dwarf-stars-eat-heavy-metals/" target="_blank" rel="noreferrer noopener">white dwarf</a>.&nbsp;



These remnants represent extreme outcomes of stellar evolution and are fundamentally different from white dwarfs.



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



Gemini is one of the twelve zodiac constellations located in the northern celestial hemisphere.&nbsp;



Its name means "twins" in Latin, reflecting its representation of the mythological twins Castor and Pollux from Greek and Roman mythology.&nbsp;



<h3 class="wp-block-heading" id="h-stars-of-gemini">Stars of Gemini</h3>



The stars Castor and Pollux, which form the heads of the twins, are the brightest stars in Gemini and are key to its identification.&nbsp;



Pollux is a bright orange giant star, while Castor is a multiple <a href="https://www.earth.com/news/exoplanet-found-in-the-habitable-zone-of-a-binary-star-system/" target="_blank" rel="noreferrer noopener">star system</a> made up of six stars.



<h3 class="wp-block-heading" id="h-neighboring-constellations">Neighboring constellations</h3>



Gemini lies between Taurus to the west and Cancer to the east, and it is bordered by several other constellations, including Orion to the south.



It is most visible in the night sky during the winter months in the Northern Hemisphere, particularly in January and February.&nbsp;



<h3 class="wp-block-heading" id="h-significance-of-gemini">Significance of Gemini</h3>



The constellation is part of the ecliptic, the path that the Sun appears to take through the sky, making it significant in both astronomy and astrology.



Astronomically, Gemini is home to several interesting deep-sky objects, including the open star cluster M35, which is easily visible with binoculars or a small telescope.&nbsp;



The constellation also contains several stars and stellar systems of interest, such as variable stars and binary systems.



<h3 class="wp-block-heading" id="h-greek-mythology-nbsp">Greek mythology&nbsp;</h3>



In Greek mythology, Castor and Pollux were the sons of Leda, but they had different fathers - Castor was mortal, while Pollux was divine, being the son of Zeus.&nbsp;



Their story is one of loyalty and brotherhood, as Pollux begged Zeus to share his immortality with Castor after his brother's death. As a result, Zeus placed them in the sky as the constellation Gemini, symbolizing their eternal bond.



<h3 class="wp-block-heading" id="h-modern-culture">Modern culture</h3>



In modern culture, Gemini continues to be associated with duality, adaptability, and communication in astrology.&nbsp;



The constellation also holds significance in space science, lending its name to NASA's Gemini program in the 1960s. This program conducted critical missions that paved the way for the Apollo moon landings.



Image Credit: ESA&nbsp;



-----



Like what you read? <a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.



Check us out on <a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by <a href="https://www.linkedin.com/in/eric-ralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a> and Earth.com.



-----

Supernova explosion captured in the constellation Gemini 

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

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.



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;



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



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>. 



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



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



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.



“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;



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



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



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.



“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;



“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;



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



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



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



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



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;



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



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



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.



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



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;



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;



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



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



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;



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



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;



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.



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



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.



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;



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



-----



Like what you read? <a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.



Check us out on <a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by <a href="https://www.linkedin.com/in/eric-ralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a> and Earth.com.



-----

Webb unveils a spiral galaxy in magnificent detail

Today's Image of the Day from NASA Earth Observatory features an active landslide zone that has been shifting for decades on the Palos Verdes Peninsula in Los Angeles County.



This area, particularly in Portuguese Bend, experiences ongoing ground movement, with land sliding toward the ocean at varying rates of up to several feet per year. 



The instability is largely due to weak, water-saturated bedrock and the effects of <a href="https://www.earth.com/news/rising-seas-sinking-cities-land-subsidence-on-the-east-coast/">human activity</a>, including road construction and irrigation, which have exacerbated the natural movement.



<h2 class="wp-block-heading" id="h-analysis-of-the-landslide-zone">Analysis of the landslide zone</h2>



According to a recent report from NASA, the landslide zone on the Palos Verdes Peninsula has expanded.&nbsp;



“Researchers at NASA’s Jet Propulsion Laboratory in Southern California used data from an airborne radar to measure the movement of the slow-moving landslides on the Palos Verdes Peninsula in Los Angeles County,” the <a href="https://earthobservatory.nasa.gov/images/153893/los-angeles-area-landslide-expands">report</a> stated.



“The analysis determined that, during a four-week period in the fall of 2024, land in the residential area slid toward the ocean by as much as 4 inches (10 centimeters) per week."



“Portions of the peninsula, which juts into the Pacific Ocean just south of the city of Los Angeles, are part of an ancient complex of landslides that has been moving for at least the past six decades, affecting hundreds of buildings in local communities.”&nbsp;



NASA noted that the motion accelerated and the active area expanded following record-breaking rainfall in Southern California in 2023 and heavy <a href="https://www.earth.com/news/rainfall-is-increasingly-unpredictable-due-to-climate-change/" target="_blank" rel="noreferrer noopener">precipitation</a> in early 2024.



<h2 class="wp-block-heading" id="h-visualization-of-the-landslide-zone">Visualization of the landslide zone</h2>



To create the image, the Advanced Rapid Imaging and Analysis (ARIA) team used data from four flights of NASA’s Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) collected between September 18 and October 17, 2024.&nbsp;



“The UAVSAR instrument was mounted to a Gulfstream III jet flown out of NASA’s Armstrong Flight Research Center in Edwards, California, and the four flights were planned to estimate the speed and direction of the landslides in three dimensions,” explained NASA.



“In the image above, colors indicate how fast parts of the landslide complex were moving in late September and October, with the darkest reds indicating the highest speeds." 



"The arrows represent the direction of horizontal motion. The white solid lines are the boundaries of the active landslide area as defined in 2007 by the California Geological Survey.”



<h2 class="wp-block-heading" id="h-accelerating-land-movement-and-risks">Accelerating land movement and risks</h2>



Alexander Handwerger is a landslide scientist at the Jet Propulsion Laboratory who performed the analysis. “In effect, we’re seeing that the footprint of land experiencing significant impacts has expanded, and the speed is more than enough to put human life and infrastructure at risk,” said Handwerger.&nbsp;



The landslide activity in this region dates back to the 1950s, when road construction projects disturbed the already <a href="https://www.earth.com/news/two-billion-people-are-threatened-by-land-subsidence/">unstable terrain</a>, accelerating movement.&nbsp;



Since then, shifting ground has led to significant damage to infrastructure, including cracked roads, broken utility lines, and distorted buildings. The instability has made it difficult for the city to maintain roads and essential services in the affected areas.



Despite efforts to slow the movement, including drainage improvements and engineering solutions, the land continues to shift. Homeowners and city officials have had to adapt, with some structures built to withstand slow movement, while others have been abandoned.&nbsp;



The situation remains a challenge, with scientists monitoring the landslide to better understand its <a href="https://www.earth.com/news/landslide-predictions-could-become-94-percent-more-accurate/">behavior</a> and explore potential mitigation strategies.



Portuguese Bend is a well-known example of a continuously active landslide, highlighting the complex interaction between geology, human development, and environmental forces.



Image Credit: NASA Earth Observatory&nbsp;



-----



Like what you read? <a href="https://www.earth.com/subscribe/">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by <a href="https://www.linkedin.com/in/eric-ralls/">Eric Ralls</a> and Earth.com.



-----

Landslide zone in Los Angeles County is expanding

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

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



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



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



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



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



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



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



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



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



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



<h2 class="wp-block-heading" id="h-characteristics-of-the-southern-ring-nebula">Characteristics of the Southern Ring Nebula </h2>



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



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



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



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



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



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



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



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



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



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



<h2 class="wp-block-heading" id="h-significance-of-the-image">Significance of the image</h2>



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



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



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



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



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



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



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



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



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



Image Credit: NASA, ESA, CSA, STScI



-----



Like what you read? <a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.



Check us out on <a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by <a href="https://www.linkedin.com/in/eric-ralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a> and Earth.com.



-----

Southern Ring Nebula in the constellation Vela 

Today's Image of the Day from the European Space Agency features the barred spiral galaxy NGC 3783, which is located about 130 million light-years away in the constellation Centaurus. 



NGC 3783 is also the most prominent of a galaxy group (by the same name) that contains 47 galaxies.&nbsp;



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



“Like galaxy clusters, galaxy groups are aggregates of gravitationally bound galaxies. Galaxy groups, however, are less massive and contain fewer members than <a href="https://www.earth.com/news/titanic-galaxy-cluster-collision-defies-all-current-understanding-of-the-universe/" target="_blank" rel="noreferrer noopener">galaxy clusters</a> do: where galaxy clusters can contain hundreds or even thousands of constituent galaxies, galaxy groups do not typically include more than 50,” noted <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



“The Milky Way is actually part of a galaxy group, known as the Local Group, which contains two other large galaxies (Andromeda and the Triangulum galaxy), as well as several dozen satellite and dwarf galaxies.”



<h2 class="wp-block-heading" id="h-a-blue-giant-star">A blue giant star</h2>



The bright object that appears to the right of the galaxy is the star HD 101274. “The perspective in this image makes the star and the galaxy look like close companions, but this is an illusion. HD 101274 lies only about 1,530 light-years from Earth, meaning it is about 85 thousand times closer than NGC 3783,” explained ESA.&nbsp;



The star is part of the NGC 3766 cluster, sometimes referred to as the Pearl Cluster, which is known for its richness in bright stars and its relatively young age.



Characterized by its high temperature and luminosity, HD 101274 is categorized as a blue giant star.



<h2 class="wp-block-heading" id="h-significance-of-blue-giants">Significance of blue giants</h2>



Blue giants are massive stars that have left the main sequence phase of stellar evolution and are burning helium or heavier elements in their cores. These stars are known for their short lifespans relative to smaller stars due to their rapid consumption of nuclear fuel.



<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> like HD 101274 are important for astronomers because they help in studying the properties of stellar populations in clusters and the dynamics of stellar evolution in different environments. 



Observations of blue giant stars can provide valuable insights into the characteristics of their atmospheres, internal structures, and the processes occurring within and around them.



<h2 class="wp-block-heading" id="h-bright-central-region-of-ngc-3783">Bright central region of NGC 3783</h2>



One of the most interesting aspects of NGC 3783 is that it harbors an active galactic nucleus. This means that its central region is exceptionally luminous, likely due to the presence of a supermassive black hole. 



The black hole is actively accreting material, which emits a substantial amount of radiation as it spirals inward and heats up.



The galaxy has been studied extensively in the ultraviolet and X-ray light spectra to understand better the properties of the accretion disk around the black hole and the complex dynamics of the material surrounding it. 



These studies are crucial for understanding the physics of active galactic nuclei and the role they play in <a href="https://www.earth.com/news/galaxies-like-our-own-milky-way-are-not-unique/" target="_blank" rel="noreferrer noopener">galaxy evolution</a>.



According to ESA, NGC 3783 is a&nbsp;Type I Seyfert galaxy. “In this image it is recorded by Hubble in incredible detail, from its glowing central bar to its narrow, winding arms and the dust threaded through them, thanks to five separate images taken in different wavelengths of light," noted ESA.



“In fact, the galactic center is bright enough to Hubble that it exhibits diffraction spikes, normally only seen on stars such as HD 101274.”



<h2 class="wp-block-heading" id="h-ngc-3783-galaxy-group">NGC 3783 galaxy group</h2>



The NGC 3783 group is part of the larger Hydra-Centaurus Supercluster, which itself is a massive collection of <a href="https://www.earth.com/news/shapes-of-one-million-galaxies-hint-at-the-universes-origins/" target="_blank" rel="noreferrer noopener">galaxies</a> and galaxy clusters located primarily in the constellations of Hydra and Centaurus.



The NGC 3783 group consists of several galaxies that are gravitationally bound and interact with each other. These interactions can influence the galaxies' evolution through mechanisms like tidal forces and merger events, which can trigger star formation, fuel central black holes, and reshape the galaxies' structures.



Studying the NGC 3783 group helps astronomers understand how <a href="https://www.earth.com/news/ceers-2112-ancient-galaxy-looks-strikingly-similar-to-ours/" target="_blank" rel="noreferrer noopener">galaxies</a> evolve together in a common gravitational environment, offering insights into the dynamics and evolution of structures on cosmic scales.



Image Credit: ESA/Hubble &amp; NASA



-----



Like what you read? <a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.



Check us out on <a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by <a href="https://www.linkedin.com/in/eric-ralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a> and Earth.com.



-----

Luminous spiral galaxy and a blue giant star

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;



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



“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>.



“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.”



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;



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



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



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;



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.



“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.



“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;



“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.”



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



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



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



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;



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



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.



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



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.



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



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;



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.



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



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;



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



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. 



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.



Image Credit: ESA/Hubble &amp; NASA



-----



Like what you read? <a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.



Check us out on <a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by <a href="https://www.linkedin.com/in/eric-ralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a> and Earth.com.



-----

Violent clash of the Antennae Galaxies  

Kings Canyon National Park&nbsp;is an American&nbsp;national park&nbsp;in the southern&nbsp;Sierra Nevada, in&nbsp;Fresno&nbsp;and&nbsp;Tulare Counties,&nbsp;California. Originally established in 1890 as General Grant National Park, the park was greatly expanded and renamed to Kings Canyon National Park on March 4, 1940. The park's namesake, Kings Canyon, is a rugged&nbsp;glacier-carved valley more than a mile (1,600&nbsp;m) deep. Other natural features include multiple 14,000-foot (4,300&nbsp;m) peaks, high mountain meadows, swift-flowing rivers, and some of the world's largest stands of&nbsp;giant sequoia&nbsp;trees. Kings Canyon is north of and contiguous with&nbsp;Sequoia National Park, and both parks are jointly administered by the&nbsp;National Park Service&nbsp;as the&nbsp;Sequoia and Kings Canyon National Parks.



There are fourteen campgrounds in these parks, including three that are open year-round. Campgrounds require reservations in advance, and sites are usually full.&nbsp;

Sequoia and Kings Canyon National Parks, California

Scientists have long wondered how the brain updates itself with new information and memories. Some ideas revolve around chemical changes in specific neurons, while others focus on structural shifts among brain cells.



<a href="https://www.tcd.ie/research/profiles/?profile=tryan6">Dr. Tomás Ryan</a> from <a href="https://www.tcd.ie" target="_blank" rel="noreferrer noopener">Trinity College Dublin</a> is among the neuroscientists who have explored these questions by tracking cells involved in <a href="https://www.earth.com/news/memory-isnt-only-stored-in-our-brains-other-cells-can-remember-too/" target="_blank" rel="noreferrer noopener">learning</a>. 



New <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(23)01512-9">findings</a> suggest memory formation hinges on connections between groups of <a href="https://www.nature.com/articles/s41380-023-02137-5">engram cells</a>, which are neurons thought to capture and store distinct experiences.



<h2 class="wp-block-heading" id="h-how-memories-become-linked">How memories become linked</h2>



Researchers believe each experience leaves a pattern of brain cell activation that can be switched on later. To see this process in action, neuroscientists tracked two sets of engram cells, each tied to a different memory. 



They discovered that when one set of cells was reactivated, the other set sometimes lit up too, as if the memories had become linked.



This idea runs counter to the old notion that an individual neuron stores an entire memory. Instead, the memory might be in the connections these <a href="https://www.earth.com/news/sleep-rewires-the-brain-to-strengthen-memories/" target="_blank" rel="noreferrer noopener">cells</a> build and reshape over time. 



Such structural rearrangements help us handle new information without losing old experiences.



<h2 class="wp-block-heading" id="h-which-brain-cells-store-memories">Which brain cells store memories?</h2>



“Memory engram cells are groups of brain cells that, activated by specific experiences, change themselves to incorporate and thereby hold information in our brain,” said <a href="https://orcid.org/0000-0002-8365-2762" target="_blank" rel="noreferrer noopener">Dr. Clara Ortega-de San Luis</a>, Postdoctoral Research Fellow and lead author on the study. 



She and her colleagues monitored how similar or related memories were stored across different brain areas. 



They used genetic techniques to label neurons that fired for one event, then watched how those same <a href="https://www.earth.com/news/smartphones-are-teaching-us-how-to-supercharge-our-memory/" target="_blank" rel="noreferrer noopener">neurons</a> responded to a second event that felt related.



One major clue came from measuring how well these labeled neurons made new links with cells that were tied to older, separate experiences. 



Optogenetics, a method that turns cells on or off with light, let them test whether blocking these newly formed links disrupted the memory.



<h2 class="wp-block-heading" id="h-how-one-protein-shapes-memory">How one protein shapes memory</h2>



A specific protein, <a href="https://molecularbrain.biomedcentral.com/articles/10.1186/s13041-019-0520-x" target="_blank" rel="noreferrer noopener">PSD-95</a>, emerged as a gatekeeper of these engram cell connections. This protein sits at nerve cell junctions called <a href="https://www.nature.com/articles/24790" target="_blank" rel="noreferrer noopener">synapses</a> and helps anchor receptor molecules.&nbsp;



When the team lowered the amount of PSD-95 in the neurons storing a given memory, these connections behaved differently. Under certain conditions, the memory seemed to linger even when researchers tried to dampen it.



That persistence hints at how the brain can hang on to memories that we might assume should fade. It also hints at why a shortage or disruption of PSD-95 could derail normal learning <a href="https://www.earth.com/news/why-memories-close-in-time-feel-connected/" target="_blank" rel="noreferrer noopener">patterns</a>.



<h2 class="wp-block-heading" id="h-brain-cells-build-on-old-memories">Brain cells build on old memories</h2>



This work taps into a broader shift in neuroscience. Rather than focusing on single cells, many researchers now examine how multiple cells form networks that hold our daily experiences. 



By using cutting-edge genetic tagging, scientists can identify where new links are happening and whether these connections are essential for recalling the <a href="https://www.earth.com/news/forgetting-things-is-a-natural-part-of-the-memory-process/" target="_blank" rel="noreferrer noopener">memory</a> later.



Many of the previous studies mapped separate steps: encoding a memory, storing it, then reactivating it. 



This project took it one step further by showing how the brain might slot fresh information into an existing network, so the old memory is updated instead of replaced.



<h2 class="wp-block-heading" id="h-why-these-findings-matter">Why these findings matter</h2>



Experts have debated how new learning manages not to overwrite older memories in the same region of the brain. According to Dr. Ryan, “we should search for information ‘between’ cells.”&nbsp;



This view suggests memories are not locked inside one specific location but scattered as connections that can be modified. If true, it may explain how we learn quickly from everyday life without dismantling what we already know.



Therapies could one day target the proteins that enable these shifting connections. If molecules like PSD-95 shape synapses to store a memory, then changing them might help reframe harmful memories tied to fear or trauma, though more studies are needed.



<h2 class="wp-block-heading" id="h-how-brain-cells-shape-daily-memory">How brain cells shape daily memory</h2>



Memory isn’t purely academic. Our daily routines demand constant learning, whether it’s recalling names, navigating busy streets, or picking up a new hobby. 



Understanding how the brain cells keep all that information flexible, yet stable, offers hope for tackling age-related memory issues or conditions that affect learning.



Additional work in the field has shown that certain neurons can take on multiple roles depending on the situation. 



Those roles often shift over time, especially when new experiences pile up. By homing in on the connections, scientists add a piece to the puzzle of how these cells adapt.



<h2 class="wp-block-heading" id="h-where-this-research-could-lead">Where this research could lead</h2>



Unraveling the complicated dance among engram cells might eventually guide how we teach, treat memory disorders, or support mental health. 



If wiring changes are at the core of learning, there might be clever ways to prompt healthy rearrangements in people struggling with conditions like post-traumatic stress or depression.



This study gives a peek into that process. It reveals a fragile, but critical, balance at the heart of learning: strengthen certain neural links for new knowledge, but keep enough structure so older skills and memories remain intact.



The study is published in <a href="https://www.cell.com/current-biology/fulltext/S0960-9822(23)01512-9" target="_blank" rel="noreferrer noopener">Current Biology</a>.



-----



Like what you read?&nbsp;<a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a>&nbsp;for engaging articles, exclusive content, and the latest updates.&nbsp;



Check us out on&nbsp;<a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by&nbsp;<a href="https://www.earth.com/author/eralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a>&nbsp;and Earth.com.



-----

How does the human brain create and retrieve memories? Scientists figured it out

Scientists have long wondered how the brain updates itself with...

Life on our planet goes back at least 3.7 billion years, and much of it started small. Researchers have studied microbial life in ancient rocks, but it has remained hard to place microbes on an exact timeline. 



New work indicates that some <a href="https://www.earth.com/news/bacteria-and-imprint-new-era-dna-transformation/" target="_blank" rel="noreferrer noopener">bacteria</a> harnessed oxygen almost one billion years earlier than scientists previously believed.



Led by <a href="https://www.researchgate.net/profile/Adrian-Davin" target="_blank" rel="noreferrer noopener">Dr. Adrián Arellano Davín</a> of the Okinawa Institute of Science and Technology (<a href="https://www.oist.jp" target="_blank" rel="noreferrer noopener">OIST</a>), this study highlights an unexpected link between early oxygen tolerance and the later rise of photosynthesis.



<h2 class="wp-block-heading" id="h-understanding-the-great-oxidation-event-goe">Understanding the Great Oxidation Event (GOE)</h2>



A huge turning point in Earth's early history is known as the Great Oxidation Event, or <a href="https://asm.org/articles/2022/february/the-great-oxidation-event-how-cyanobacteria-change" target="_blank" rel="noreferrer noopener">GOE</a> for short. It happened around 2.4 billion years ago, when <a href="https://royalsocietypublishing.org/doi/10.1098/rstb.2006.1838" target="_blank" rel="noreferrer noopener">oxygen</a> started building up in the atmosphere for the first time. 



Before that, there was barely any oxygen in the air - life existed, but it was mostly tiny microbes that didn’t need it. Or, as we're learning from this study, a few species of bacteria that learned to use it before it became prevalent in the atmosphere.



At first, that oxygen got soaked up by things like iron in the oceans, but eventually, it started leaking into the air.



Once oxygen began to stick around in the atmosphere, it changed everything. Some life forms couldn’t handle it and died off, but others adapted and thrived. 



This event set the stage for more complex life to evolve down the road.



<h2 class="wp-block-heading" id="h-bacteria-used-oxygen-before-air-changed">Bacteria used oxygen before air changed</h2>



Scientists have assumed that most <a href="https://www.earth.com/news/23-new-marine-bacteria-species-discovered-that-influence-global-ocean-cycles/" target="_blank" rel="noreferrer noopener">bacteria</a> stayed anaerobic until the onset of the <a href="https://www.earth.com/news/it-took-200-million-years-for-earth-to-get-its-oxygen/" target="_blank" rel="noreferrer noopener">GOE</a>. The new investigation challenges that assumption.



Clues suggest certain bacterial lineages adapted to oxygen at least 900 million years before the GOE. This surprising result implies that small amounts of oxygen were present in pockets of Earth’s environment. 



Such an ability to work with trace oxygen may have paved the way for modern forms of respiration.



<h2 class="wp-block-heading" id="h-early-oxygen-use-gave-bacteria-an-advantage">Early oxygen use gave bacteria an advantage</h2>



Energy production in cells is crucial, and oxygen-based metabolism is notably more efficient than methods that rely on other <a href="https://www.earth.com/news/new-antibiotic-found-in-soil-has-potential-to-fight-superbugs/" target="_blank" rel="noreferrer noopener">substances</a>. 



Before atmospheric oxygen rose, most organisms relied on <a href="https://www.ucsfhealth.org/medical-tests/anaerobic-bacteria" target="_blank" rel="noreferrer noopener">anaerobic</a> paths. Gaining even a slight advantage by using oxygen could have given those early aerobic <a href="https://www.earth.com/news/bacteria-strain-identified-that-can-eat-forever-chemicals/" target="_blank" rel="noreferrer noopener">microbes</a> a head start.



“This combined approach of using genomic data, fossils, and Earth’s geochemical history brings new clarity to evolutionary timelines, especially for microbial groups that don’t have a fossil record,” said <a href="https://www.oist.jp/research/research-units/modevolgenom/gergely-janos-szollosi" target="_blank" rel="noreferrer noopener">Professor Gergely Szöllősi</a>, leader of the <a href="https://www.oist.jp/research/research-units/modevolgenom/gergely-janos-szollosi" target="_blank" rel="noreferrer noopener">Model-based Evolutionary Genomics Unit</a> at OIST.



<h2 class="wp-block-heading" id="h-the-role-of-machine-learning">The role of machine learning</h2>



Scientists used machine learning alongside <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC9632901/" target="_blank" rel="noreferrer noopener">phylogenetic reconciliation</a> to reconstruct which ancestral bacteria may have used oxygen. 



By looking at patterns across 1,007 modern <a href="https://www.earth.com/news/soil-bacteria-and-fungi-respond-differently-to-urbanization/" target="_blank" rel="noreferrer noopener">bacterial genomes</a>, the method predicted points where lineages switched from anaerobic to aerobic lifestyles.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/04/Bacterial-evolution_oxygen-adaptation_chart_credit-OIST_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2025/04/Bacterial-evolution_oxygen-adaptation_chart_credit-OIST_1s.webp" alt="Bacterial evolution and oxygen adaptation: A timeline built from genomic, fossil, and chemical data. Colors show oxygen states: anaerobic (blue), aerobic (red), and proportion of aerobic lineages in modern bacterial phyla (purple shades). Analysis includes mitochondria and plastids to leverage eukaryotic fossil data. Land plants and animals are shown for time reference. Credit: OIST" class="wp-image-1964457"/></a><figcaption class="wp-element-caption">Bacterial evolution and oxygen adaptation: A timeline built from genomic, fossil, and chemical data. Colors show oxygen states: anaerobic (blue), aerobic (red), and proportion of aerobic lineages in modern bacterial phyla (purple shades). Analysis includes mitochondria and plastids to leverage eukaryotic fossil data. Land plants and animals are shown for time reference. Click image to enlarge. Credit: OIST</figcaption></figure>



Modern labs have begun using these computational techniques to shed light on evolutionary puzzles that lack physical fossil evidence. 



Researchers found that lineages with <a href="https://www.sciencedirect.com/topics/earth-and-planetary-sciences/oxygen-metabolism" target="_blank" rel="noreferrer noopener">oxygen-based metabolism</a> spread further and diversified more quickly once the atmosphere changed.



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



The study points out that <a href="https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/cyanobacteria" target="_blank" rel="noreferrer noopener">cyanobacteria</a> - the group known for introducing oxygenic photosynthesis - may have already been primed to handle oxygen. 



Evidence hints that an ancestor of this group had an aerobic phase, which might have helped it develop photosynthetic <a href="https://www.earth.com/news/bacteria-pseudomonas-build-tiny-nano-spearguns-to-fight-back-against-attack/" target="_blank" rel="noreferrer noopener">genes</a>.



“Our work also shows that modeling microbial traits from their genomes using machine learning works well for studying the spread of aerobic metabolisms,” said <a href="https://www.bristol.ac.uk/people/person/Tom-Williams-09520f33-b160-4776-a3fc-e375215ae687/" target="_blank" rel="noreferrer noopener">Dr. Tom Williams</a>, a researcher from the University of Bristol’s <a href="https://www.bristol.ac.uk/biology/" target="_blank" rel="noreferrer noopener">School of Biological Sciences</a>. 



The presence of genes for managing oxygen could have set the stage for the development of photosynthesis later on.



<h2 class="wp-block-heading" id="h-existence-of-oxygen-using-bacteria">Existence of oxygen-using bacteria</h2>



Scientists mapped bacterial family histories back to the <a href="https://www.earth.com/earthpedia-articles/the-history-of-earth-in-exactly-2000-words/" target="_blank" rel="noreferrer noopener">Hadean or earliest Archaean era</a>, roughly 4.4 to 3.9 billion years ago.



Several major groups emerged and radiated well before the <a href="https://www.earth.com/news/microfossils-reveal-a-leap-in-lifes-complexity-2-4-billion-years-ago/" target="_blank" rel="noreferrer noopener">GOE</a>. Families that adopted oxygen-based lifestyles were able to thrive and multiply once oxygen became plentiful.



By analyzing both geological and genomic data, researchers placed maximum age limits on groups that rely on oxygen. Anything that needed oxygen to survive could not have existed long before free oxygen was available.



Yet the data showed that a few select lineages managed to eke out an aerobic existence in localized habitats.



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



Ancient bacterial evolution remains a tough subject to nail down. 



Fossils are rare for microbes, which means researchers must rely on chemical signals in sediments and advanced computational methods. These techniques fill the gaps left by the limited record of ancient life.



“This combined use of different data types can help us figure out not only when bacteria evolved but also how they adapted,” said Dr. Davín. 



Cross-referencing oxygen-related genes with global events paints a clearer picture of the factors that steered bacterial diversity.



<h2 class="wp-block-heading" id="h-what-comes-next">What comes next</h2>



Questions remain about how oxygen pockets formed before the GOE and how widespread they might have been. Scientists are also curious whether other organisms besides bacteria adapted to these oxygen pockets. 



Future work may involve examining additional traits, such as antibiotic resistance or carbon fixation, to see how they appeared in tandem with environmental changes.



Understanding ancient <a href="https://www.nature.com/articles/s41587-021-01130-z" target="_blank" rel="noreferrer noopener">microbial lineages</a> can shed light on the conditions that fostered eukaryotes and, eventually, complex life forms like animals and plants. 



Early oxygen tolerance in microbes might have played a big part in shaping the biosphere we see today.



-----



Featured image: An artistic conception of the early Earth, showing a surface pummeled by large impact, resulting in extrusion of deep-seated magma onto the surface. Credit: <a href="https://www.nasa.gov" target="_blank" rel="noreferrer noopener">NASA</a>/Simone Marchi



The study is published in <a href="https://www.science.org/doi/10.1126/science.adp1853" target="_blank" rel="noreferrer noopener">Science</a>.



-----



Like what you read?&nbsp;<a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a>&nbsp;for engaging articles, exclusive content, and the latest updates.&nbsp;



Check us out on&nbsp;<a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by&nbsp;<a href="https://www.earth.com/author/eralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a>&nbsp;and Earth.com.



-----

Earth's first bacteria used oxygen about one billion years earlier than we thought

Life on our planet goes back at least 3.7 billion...

Aloe vera is a familiar name in everyday skincare and therapeutic products. Many people trust its soothing gel to help with various skin concerns or to add a gentle touch to cosmetics. 



While the gel is widely used, the leftover aloe peels become waste that might reach millions of tons each year.



This issue recently caught the attention of <a href="https://www.researchgate.net/profile/Debasish-Bandyopadhyay-2">Debasish Bandyopadhyay</a>, an assistant professor in chemistry at The <a href="https://www.utrgv.edu" target="_blank" rel="noreferrer noopener">University of Texas Rio Grande Valley</a>, who explored turning the discarded rinds into a natural <a href="https://www.earth.com/news/insecticides-may-be-helping-weeds-thrive/" target="_blank" rel="noreferrer noopener">insecticide</a>.



<h2 class="wp-block-heading" id="h-aloe-waste-peels-found-new-purpose">Aloe waste peels found new purpose</h2>



Aloe vera fields, located in places such as Australia, China, India, South Africa, and the U.S., focus on harvesting gel from the thick leaves. The outer covering is rarely used on a large scale.



Some people blend gel with onions or other ingredients to repel bugs, but that approach often leaves the peels out of the equation. 



Hoping to address that gap, researchers decided to test the peels for possible <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC9862941/#:~:text=Phytochemicals%20are%20plant%2Dbased%20bioactive,have%20been%20discovered%20to%20date." target="_blank" rel="noreferrer noopener">phytochemicals</a> that might discourage insects.



They noticed that many bugs refuse to munch on the <a href="https://www.earth.com/news/some-plants-can-absorb-and-neutralize-plastic-pollution/" target="_blank" rel="noreferrer noopener">plants</a>. That observation led them to check whether the same compounds protecting aloe in nature could help farms in regions plagued by pests.



They dried the rinds at room temperature without sunlight. This step preserved valuable properties that might otherwise degrade under harsh conditions.



<h2 class="wp-block-heading" id="h-aloe-waste-extract-kills-bugs">Aloe waste extract kills bugs</h2>



Scientists analyzed peel extracts made with different solvents, including dichloromethane (<a href="https://pubchem.ncbi.nlm.nih.gov/compound/Methylene-Chloride" target="_blank" rel="noreferrer noopener">DCM</a>). They discovered potent activity against insects that destroy <a href="https://www.earth.com/news/pesticides-affect-bumble-bee-health-in-complex-ways/" target="_blank" rel="noreferrer noopener">crops</a>.



“We identified [certain substances] as potential insecticidal compounds,” said Bandyopadhyay. These molecules appeared safe for people while still packing a punch against pests.



Tests showed the insect-killing capabilities might relate to <a href="https://www.cancer.gov/publications/dictionaries/cancer-terms/def/bioactive-compound" target="_blank" rel="noreferrer noopener">bioactive substances</a> that disrupt insects’ feeding behavior. That disruption may eventually cause the insects to die, offering a more natural defense for vulnerable fields.



Early findings suggest the compounds in aloe peels could also have antibacterial or antifungal properties. Researchers continue to catalog more elements hidden in the dried peel.



<h2 class="wp-block-heading" id="h-farmers-and-the-environment">Farmers and the environment</h2>



Crop losses to insects can be huge, pushing many farmers toward strong chemical <a href="https://www.earth.com/news/fish-pesticide-exposure-impacts-their-behavior-in-both-current-and-future-generations/" target="_blank" rel="noreferrer noopener">pesticides</a>. A 2021 review in the journal <a href="https://www.mdpi.com/1420-3049/26/16/4835" target="_blank" rel="noreferrer noopener">Molecules</a> revealed that the heavy use of these chemicals harms the environment, creates resistant pests, and endangers people’s health.



Natural alternatives that rely on plant-derived elements often offer a kinder impact on local ecosystems. They break down faster, target pests without lingering in soil or water, and pose fewer risks for farmworkers.



Turning aloe waste into a new defense strategy brings financial and environmental upsides. It transforms what was formerly “trash” into a resource that can help feed populations reliant on staple crops.



A shift to plant-based pest controls may also align with sustainable farming approaches. Researchers see aloe-based insecticide as another tool in this more balanced strategy.



<h2 class="wp-block-heading" id="h-practical-plans-with-aloe-spray">Practical plans with aloe spray</h2>



Real-world testing is the next step to verify how peel extracts perform against pests in places where insects often threaten staple grains and vegetables. 



The researchers want to confirm how strongly the compounds repel or eliminate harmful bugs in open fields.



Studies into any anti-mosquito or anti-tick properties of these extracts are also under way. 



“By creating an insecticide that avoids hazardous and poisonous synthetic <a href="https://www.earth.com/news/pesticide-exposure-increases-the-risk-of-parkinsons-disease/" target="_blank" rel="noreferrer noopener">chemicals</a>, we can help the agricultural field,” said Bandyopadhyay. If the extracts repel disease-carrying pests, there might be a public health benefit too.



This approach could cut back on synthetic pesticides, which often have harsh side effects. Natural methods can still be powerful if used correctly and monitored for consistent quality.



Peel-based formulations could be simpler to handle than certain standard pesticides. This method might bring cost savings for farmers who pay high prices for chemical products.



<h2 class="wp-block-heading" id="h-anti-aging-properties-of-aloe">Anti-aging properties of aloe</h2>



In addition to being a great insecticide, aloe vera packs a surprising punch when it comes to anti-aging. 



It’s loaded with antioxidants like vitamins C and E, which help fight off free radicals - the little troublemakers that speed up wrinkles and skin damage. 



Aloe also encourages <a href="https://www.earth.com/news/scientists-discover-a-protein-that-reverses-cellular-aging/" target="_blank" rel="noreferrer noopener">collagen production</a>, which is a big deal because collagen keeps your skin firm, bouncy, and smooth. 



As we get older, our natural collagen levels dip, so giving it a boost can help reduce fine lines and keep skin looking fresh.



On top of all that, aloe is a hydration hero. It soaks into the skin fast and locks in moisture, which helps plump things up and make your face look more youthful and dewy. 



It also <a href="https://www.earth.com/news/scratching-that-itch-science-confirms-it-only-makes-rashes-worse/" target="_blank" rel="noreferrer noopener">soothes inflammation</a>, evens out skin tone, and can help calm down any irritation or redness that tends to make aging skin look a little tired.



<h2 class="wp-block-heading" id="h-aloe-waste-and-sustainable-farming">Aloe waste and sustainable farming</h2>



Researchers are collaborating with growers and local producers to see if these extracts fit into their routine spraying practices. They want to ensure that the product meets safety guidelines without being burdensome to apply.



Experts continue to measure the shelf life of this plant-based solution. Proper drying and storage can help maintain stability, ensuring that farmers and communities benefit from a reliable product.



Many wonder if large-scale aloe peel recycling can become a fresh revenue stream. If it does, aloe growers will have an added reason to collect the rinds rather than sending them off as compost or letting them rot.



Sustainability is the underlying theme of this new venture. Adding aloe peel extracts to pest management could aid global efforts to grow healthy produce while protecting soil, water, and wildlife.



The press release is published <a href="https://www.acs.org/pressroom/newsreleases/2023/august/discarded-aloe-peels-could-be-sustainable-natural-insecticide-video.html" target="_blank" rel="noreferrer noopener">here</a>.



-----



Like what you read?&nbsp;<a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a>&nbsp;for engaging articles, exclusive content, and the latest updates.&nbsp;



Check us out on&nbsp;<a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by&nbsp;<a href="https://www.earth.com/author/eralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a>&nbsp;and Earth.com.



-----

Wonder plant: This natural insect repellent also has anti-aging properties

Aloe vera is a familiar name in everyday skincare and...

Nitrous oxide, better known as laughing gas, is making headlines for all the wrong reasons. Despite warnings from the Food and Drug Administration (<a href="https://www.fda.gov" target="_blank" rel="noreferrer noopener">FDA</a>), more people across the U.S. are misusing the substance - often with tragic results.



Once a common feature in dental offices and whipped cream canisters, this gas is now tied to a sharp increase in poisonings, hospitalizations, and even deaths.



Researchers from the <a href="https://olemiss.edu/" target="_blank" rel="noreferrer noopener">University of Mississippi</a> and the University of Illinois at Urbana-Champaign are investigating this growing trend, sounding the alarm about its risks. 



“This is a chemical that is commonly used as a <a href="https://www.earth.com/news/natures-sleep-aid-cannabinol-shows-promise-as-a-safe-sedative/" target="_blank" rel="noreferrer noopener">sedative</a> or anesthetic, but what we’re seeing is a rise in recreational use,” said Andrew Yockey, University of Mississippi assistant professor of public health. 



“But what we’re also seeing is also a rise in hospitalizations, in poisonings and in deaths.”



<h2 class="wp-block-heading" id="h-nitrous-oxide-deaths-are-doubling">Nitrous oxide deaths are doubling</h2>



According to the 2023 National Survey on Drug Use and Health, over 13 million Americans have misused nitrous oxide at some point in their lives. 



And the Centers for Disease Control and Prevention (<a href="https://www.cdc.gov/index.html" target="_blank" rel="noreferrer noopener">CDC</a>) reports that deaths from nitrous oxide poisoning have more than doubled - rising over 110% between 2019 and 2023.



While the number of deaths remains relatively low compared to other <a href="https://www.earth.com/news/illegal-drugs-can-now-be-detected-in-the-air/" target="_blank" rel="noreferrer noopener">drugs</a>, the speed of the increase is cause for concern. 



“The preliminary findings of our study are that deaths have remained fairly small compared to other dangerous substances,” said Rachel Hoopsick, assistant professor of health and kinesiology at the <a href="https://illinois.edu" target="_blank" rel="noreferrer noopener">University of Illinois at Urbana-Champaign</a>.



“But what we’re seeing is that over the last couple of years, those rates have increased exponentially. At that continued rate, we could be looking at a much larger problem.”



<h2 class="wp-block-heading" id="h-why-nitrous-oxide-slips-under-the-radar">Why nitrous oxide slips under the radar</h2>



Whippets - another name for nitrous oxide canisters - have long been used for a quick, euphoric high.



But the side effects are no joke. The FDA warns that repeated inhalation can lead to <a href="https://www.earth.com/news/even-mild-inflammation-can-majorly-damage-the-brain/" target="_blank" rel="noreferrer noopener">brain damage</a>, frostbite, numbness, blood clots, and even paralysis. 



Despite these warnings, the gas remains widely accessible and largely unregulated.



Unlike many controlled substances, nitrous oxide is easy to buy online or at local shops. A simple search brings up brightly packaged, flavored options - clearly designed to catch the attention of younger audiences.



“Think back to big <a href="https://www.earth.com/news/tobacco-bans-could-help-prevent-1-2-million-lung-cancer-deaths/" target="_blank" rel="noreferrer noopener">tobacco</a>; they deliberately targeted young people with cartoons, fun flavors and flashy colors,” said Hoopsick. “That is a parallel we’re seeing now with nitrous oxide."



The product is often marketed as a whipped cream propellant. But some of the available options make the culinary angle hard to believe. 



“I really doubt anyone is buying flavored nitrous oxide to make blueberry mango whipped cream,” Yockey said. “Or ‘Bomb Pop.’ But I can have it delivered to my house in a couple of days.”



<h2 class="wp-block-heading" id="h-marketing-tactics-that-mimic-big-tobacco">Marketing tactics that mimic big tobacco</h2>



What’s even more alarming is how sellers downplay the risks. 



“We have evidence that nitrous oxide poisoning is a very real danger, but this is very often ignored or trivialized,” said Hoopsick. 



“Sellers of nitrous oxide rarely, if ever, provide health warnings. I think the public sees it as a <a href="https://www.earth.com/news/mdma-and-methamphetamine-spark-human-connections-that-prove-beneficial-in-therapy/" target="_blank" rel="noreferrer noopener">party drug</a>.”



And like many dangerous trends, social media is making things worse. Videos of teens and young adults inhaling the gas are easy to find online, often glamorized with hashtags and flashy effects. 



“We know that if you watch videos of someone else doing it, you’re more likely to try it,” said Yockey. 



“I worry about the high school and college-aged adolescents who see this online and decide to buy a fruit-punch flavored tank. Because right now, that’s perfectly legal.”



<h2 class="wp-block-heading" id="h-a-call-for-policy-change">A call for policy change</h2>



The researchers believe that more data is needed to understand the full impact of nitrous oxide misuse. But they also stress that legislation must catch up with reality. 



“Policy level interventions are what are lacking at the moment,” Hoopsick said. 



“If we have some guardrails on who can sell this, who can buy it and how it’s marketed, maybe we can get ahead of the problem.”



For now, the listings keep growing. And with speedy shipping options, the danger is just a few clicks away. 



“Some of these brands were not here even a week ago,” Yockey said, scrolling through listings on his screen. “What they’re doing here is very ingenious, but it’s also incredibly dangerous.”



-----



Like what you read? <a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.&nbsp;



Check us out on <a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by <a href="https://www.earth.com/author/eralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a> and Earth.com.



-----

Laughing gas crisis: Nitrous oxide misuse and abuse is rising in the U.S.

Nitrous oxide, better known as laughing gas, is making headlines...

Sacred,Chinamapere,Rock-art,Near,Chimoio,,Mozambique,Rock-art,Near,Manica,,Mozambique

More than 12,000 years ago, Europe's prehistoric hunter-gatherers faced extreme shifts in climate. These changes, brought on by the final stages of the Ice Age, had a powerful effect on how the human population lived, where they moved, and how many of them could survive.



A new study traces how these ancient communities responded to both warming and cooling periods, revealing large swings in population size and movement across the continent.



The research was led by a team of 25 archaeologists, including scientists from the <a href="https://www.uni-koeln.de/en/" target="_blank" rel="noreferrer noopener">University of Cologne</a>, and involved experts from twenty European universities and institutions. 



Their findings, recently published in PLOS One, focus on the Final Palaeolithic period, between 14,000 and 11,600 years ago. 



This study provides a clearer picture of population growth, decline, and migration in response to two major climate phases: a warm period known as Greenland Interstadial 1d-a (GI-1d-a), and a sharp cold snap called Greenland Stadial 1 (GS-1), also known as the <a href="https://www.earth.com/news/prehistoric-comet-impact-triggered-the-invention-of-agriculture/" target="_blank" rel="noreferrer noopener">Younger Dryas</a>.



<h2 class="wp-block-heading" id="h-climate-driven-boom-and-bust">Climate-driven boom and bust</h2>



During the warmer GI-1d-a period, <a href="https://www.earth.com/news/early-humans-impacted-earth-than-previously-thought-2/" target="_blank" rel="noreferrer noopener">early humans</a> began expanding into northern and northeastern central Europe. 



This marked a turning point, as these areas became major population centers for the first time in prehistory. 



At the same time, parts of southwestern Europe - especially Spain and France - saw a decline in population compared to earlier <a href="https://www.earth.com/news/humans-and-neanderthals-may-have-co-existed-for-many-years/" target="_blank" rel="noreferrer noopener">Upper Palaeolithic</a> periods.



But when the climate took a dramatic turn during GS-1, the population across Europe dropped sharply. Researchers estimate that during this cold phase, the number of people was reduced by half. 



Despite this overall collapse, the pattern wasn’t uniform. Some regions bucked the trend. Parts of northern Italy, Poland, and northeastern Germany actually saw stable or slightly rising population numbers. 



These pockets of resilience suggest that some groups migrated eastward to seek more livable conditions.



“These observations probably reflect the eastward movement of people in response to the very abrupt and pronounced <a href="https://www.earth.com/news/extreme-cooling-event-caused-extinction-of-first-early-humans-in-europe/" target="_blank" rel="noreferrer noopener">climatic cooling</a> during the Younger Dryas,” explains Dr. Isabell Schmidt from the University of Cologne’s Department of Prehistoric Archaeology. 



“Humans during the Final Palaeolithic apparently responded by migrating to more favourable areas.”



<h2 class="wp-block-heading" id="h-mapping-the-past-with-modern-tools">Mapping the past with modern tools</h2>



To track these demographic shifts, the researchers compiled a comprehensive database of archaeological sites from the Final Palaeolithic. 



They then applied a geostatistical method known as the Cologne Protocol to estimate how many people lived in each area and how densely populated those regions were. 



This standardized method helps archaeologists compare population data across time and space more reliably.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2025/04/europe_population-shift_last-ice-age_Map_PLOS-ONE_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2025/04/europe_population-shift_last-ice-age_Map_PLOS-ONE_1s.webp" alt="Green dots: GI-1d-a; blue dots: GS-1. Filled circles: dataset B (chronologically subdivided sites); filled and open circles: dataset A (all sites; see text and Fig 1). Base map made with Natural Earth. Credit: PLoS One" class="wp-image-1964446"/></a><figcaption class="wp-element-caption">Green dots: GI-1d-a; blue dots: GS-1. Filled circles: dataset B (chronologically subdivided sites); filled and open circles: dataset A (all sites; see text and Fig 1). Base map made with Natural Earth. Click to enlarge. Credit: PLoS One</figcaption></figure>



The study highlights how early humans didn’t just endure climate change - they responded to it.



By moving into new territories or concentrating in more stable regions, they adapted their way of life to changing temperatures and environmental stress. 



This pattern of climate-driven migration adds a new layer of understanding to our species’ long history of <a href="https://www.earth.com/news/climate-disruption-threatens-humanitys-survival/" target="_blank" rel="noreferrer noopener">survival</a> and adaptation.



<h2 class="wp-block-heading" id="h-europe-has-seen-climate-linked-population-drops-before">Europe has seen climate-linked population drops before</h2>



This isn’t the first time Europe saw a large population decline during prehistory. 



The researchers point out that a similar drop happened during the late Gravettian period, roughly between 29,000 and 25,000 years ago, when colder temperatures wiped out regional groups and reduced populations in western and central Europe by up to two-thirds.



Still, there’s much left to learn. Early demographic changes remain difficult to trace with precision, but this study adds new evidence to a growing pool of research. 



By looking closely at how ancient humans handled the ups and downs of the Ice Age, this research brings us one step closer to understanding the deep history of human resilience - and how that resilience may still guide us in facing today’s environmental changes.



The work was part of the long-running&nbsp;<a href="https://www.sfb806.uni-koeln.de/" target="_blank" rel="noreferrer noopener">Collaborative Research Centre 806 - Our Way to Europe</a>, based at the&nbsp;University of Cologne&nbsp;and funded by the&nbsp;<a href="https://www.dfg.de/en/" target="_blank" rel="noreferrer noopener">German Research Foundation</a>&nbsp;between 2009 and 2021.



It is now being continued under the <a href="https://hescor.uni-koeln.de/" target="_blank" rel="noreferrer noopener">HESCOR project</a> (Human and Earth System Coupling Research), supported by the Ministry of Culture and Science of the State of North Rhine-Westphalia.



The full study was published in the journal <a href="https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0310942" target="_blank" rel="noreferrer noopener">PLOS One</a>.



-----



Like what you read? <a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.&nbsp;



Check us out on <a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by <a href="https://www.earth.com/author/eralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a> and Earth.com.



-----

Ice Age climate shifts changed early human migration  patterns

More than 12,000 years ago, Europe's prehistoric hunter-gatherers faced extreme...

Most people have heard that cannabis can boost mood, but not everyone realizes that it can also bring on nervous feelings and anxiety in certain situations. 



<a href="https://onlinelibrary.wiley.com/doi/abs/10.1111/add.14842" target="_blank" rel="noreferrer noopener">Interest in balancing</a> these effects is soaring, with many folks wondering if specific parts of the cannabis plant might soften the jangled moods tied to its psychoactive <a href="https://www.earth.com/news/tapping-into-the-pain-relief-potential-of-cannabis-without-the-high/" target="_blank" rel="noreferrer noopener">component</a>.



This newly published work comes from <a href="https://profiles.hopkinsmedicine.org/provider/ryan-g-vandrey/2777317" target="_blank" rel="noreferrer noopener">Ryan Vandrey, PhD,</a> professor of psychiatry and behavioral sciences at the Johns Hopkins University School of Medicine.



He and his team uncovered fascinating details about an essential oil that appears to dampen the jittery edge often sparked by <a href="https://www.earth.com/news/medicinal-cannabis-helped-patients-feel-better-for-a-full-year/" target="_blank" rel="noreferrer noopener">THC</a>.



<h2 class="wp-block-heading" id="h-thc-can-relax-or-cause-anxiety">THC can relax or cause anxiety</h2>



<a href="https://www.samhsa.gov/data/report/2020-nsduh-annual-national-report" target="_blank" rel="noreferrer noopener">Experts</a> say more people in the United States are giving <a href="https://www.earth.com/news/young-cannabis-users-face-higher-heart-attack-risk/" target="_blank" rel="noreferrer noopener">cannabis</a> a try these days. Some do it for medical reasons, while others do it for casual relaxation.



<a href="https://www.cancer.gov/publications/dictionaries/cancer-terms/def/psychoactive-substance" target="_blank" rel="noreferrer noopener">Psychoactive compounds</a> affect mood and perception. THC, the main psychoactive part of cannabis, can prompt both calm and stress. 



Determining how it influences our minds is central to figuring out ways to reduce the negative side of the experience.



<h2 class="wp-block-heading" id="h-reduced-cannabis-linked-mood-anxiety">Reduced cannabis-linked mood anxiety</h2>



The research spotlight is on d-limonene, a terpene in citrus fruits. A terpene is a <a href="https://pubmed.ncbi.nlm.nih.gov/38932560/" target="_blank" rel="noreferrer noopener">naturally occurring oil</a> that can influence taste and scent in plants.



Preclinical results have hinted that d-limonene might help with <a href="https://pmc.ncbi.nlm.nih.gov/articles/PMC9774566/" target="_blank" rel="noreferrer noopener">anxious</a> moods. Many have wondered if it could work in combination with <a href="https://www.earth.com/news/cbd-reduces-the-unwanted-side-effects-of-thc/" target="_blank" rel="noreferrer noopener">THC</a> to curb the uncomfortable restlessness some people feel.



<h2 class="wp-block-heading" id="h-understanding-d-limonene-the-basics">Understanding d-limonene - the basics</h2>



D-limonene is a natural compound that gives <a href="https://www.earth.com/news/citrus-fruits-where-did-they-come-from-and-how-would-we-live-without-them/" target="_blank" rel="noreferrer noopener">citrus fruits</a> their fresh, zesty smell. Basically, it's what makes oranges smell like oranges. 



It’s found in the peels of lemons, limes, oranges, and other <a href="https://www.earth.com/news/fruits-and-plants-are-powerful-allies-for-disease-prevention/" target="_blank" rel="noreferrer noopener">citrus fruits</a>, and companies often extract it to use in cleaning products, air fresheners, and even food flavorings. 



It’s oily, smells amazing, and happens to be a pretty effective solvent, which makes it great for cutting through grease and grime.



Some research suggests it might have anti-inflammatory, antioxidant, and even anti-cancer properties, though scientists are still figuring out the full picture. 



It’s also used in some natural insect repellents and eco-friendly products because it's biodegradable and less harsh than many synthetic chemicals.



<h2 class="wp-block-heading" id="h-cannabis-blends-vs-anxiety-changes">Cannabis blends vs. anxiety changes</h2>



Twenty healthy adults, averaging 26 years old, took part in as many as 10 test visits. 



Each participant inhaled various mixtures that included <a href="https://www.earth.com/news/cannabis-use-impacts-working-memory-and-brain-function/" target="_blank" rel="noreferrer noopener">THC</a> alone, d-limonene alone, a combination of both, or a placebo (4).



Researchers measured mood shifts, vital signs, and cognitive changes. They also examined blood and urine to see how THC and d-limonene moved through the body. 



The goal was to see if adding d-limonene could help people stay more at ease.



<h2 class="wp-block-heading" id="h-d-limonene-eased-cannabis-anxiety">D-limonene eased cannabis anxiety</h2>



The new <a href="https://www.sciencedirect.com/science/article/pii/S0376871624001881" target="_blank" rel="noreferrer noopener">study</a> found that d-limonene lowered reports of anxious or paranoid feelings with <a href="https://www.earth.com/news/high-potency-cannabis-use-linked-to-epigenetic-changes/" target="_blank" rel="noreferrer noopener">THC</a>. That was true when used with higher levels of THC.



Ratings of other THC effects, such as changes in thought patterns and overall relaxation, were not altered when d-limonene was introduced. 



The essential oil by itself produced no changes in mood, heart rate, or mental clarity that stood out from the placebo.



<h2 class="wp-block-heading" id="h-managing-cannabis-anxiety">Managing cannabis anxiety</h2>



“Our study demonstrates that d-limonene can modulate the effects of THC in a meaningful way and make THC more tolerable to people using it for both therapeutic and non-therapeutic purposes,” said Vandrey. 



His team believes adding d-limonene may widen the comfort range for folks who rely on THC, especially if they are prone to anxiety.



“This study is a first step in uncovering how we can mitigate risks of THC when used in medicine, and also is targeted at making cannabis safer for the general, non-therapeutic consumer,” said <a href="https://profiles.hopkinsmedicine.org/provider/tory-r-spindle/2777649" target="_blank" rel="noreferrer noopener">Tory Spindle, PhD</a>, associate professor of psychiatry and behavioral sciences at the Johns Hopkins University <a href="https://www.hopkinsmedicine.org/som" target="_blank" rel="noreferrer noopener">School of Medicine</a>.



He hopes to test other terpenes that may work in tandem with THC.



<h2 class="wp-block-heading" id="h-potential-impact-on-medical-treatments">Potential impact on medical treatments</h2>



THC-containing <a href="https://pubmed.ncbi.nlm.nih.gov/9223837/" target="_blank" rel="noreferrer noopener">medicines</a> already help with certain conditions, such as chronic pain or chemotherapy-induced nausea. 



However, high doses can sometimes be challenging for people who are easily rattled by the psychoactive “high.”



More studies will show if d-limonene can consistently cushion those uneasy feelings. The prospect of an essential oil that smoothly partners with THC could change how some medical users approach dosing.



<h2 class="wp-block-heading" id="h-thc-d-limonene-and-future-health">THC, d-limonene, and future health</h2>



Scientists plan to explore ways to administer THC and d-limonene together in oral forms. They are also eyeing different dose ranges that may yield the strongest relief.



They believe these steps will add clarity to how cannabis components mesh under real-world conditions. Larger, more diverse participant groups may reveal whether d-limonene works similarly for everyone.



There is still much to learn about how cannabis chemicals interact, especially in relation to anxiety. Though d-limonene appears promising, experts say these findings need to be replicated more widely.



People interested in experimenting with a d-limonene combination should talk to a healthcare provider. Personal tolerance matters, and controlled dosing is best done under professional guidance.



The study is published in <a href="https://www.sciencedirect.com/science/article/abs/pii/S0376871624001881?via%3Dihub" target="_blank" rel="noreferrer noopener">Drug and Alcohol Dependence</a>.



-----



Like what you read?&nbsp;<a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a>&nbsp;for engaging articles, exclusive content, and the latest updates.&nbsp;



Check us out on&nbsp;<a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by&nbsp;<a href="https://www.earth.com/author/eralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a>&nbsp;and Earth.com.



-----

Common essential oil proven to reduce cannabis-related anxiety and paranoia

Most people have heard that cannabis can boost mood, but...

Amygdala,In,The,Brain,,And,Closeup,View,Of,Amygdala,Neurons,

The brain plays a central role in guiding us to eat or drink, even when we’re not consciously thinking about it. Most of us reach for a snack or a glass of water without much thought, but behind the scenes, the brain is working hard.



A complex system of signals, cells, and communication networks helps us stay fueled and hydrated. Still, scientists are only beginning to understand how the brain figures out what the body needs — and when.



New research from the <a href="https://www.bi.mpg.de/en" target="_blank" rel="noreferrer noopener">Max Planck Institute for Biological Intelligence</a>, working with the <a href="https://www.uni-regensburg.de/en" target="_blank" rel="noreferrer noopener">University of Regensburg</a> and <a href="https://www.stanford.edu" target="_blank" rel="noreferrer noopener">Stanford University</a>, shines a light on a specific part of the brain that may be responsible for pushing us to eat or drink.



The team studied mice and found that certain groups of neurons in the <a href="https://www.earth.com/news/how-does-the-brain-identify-rewards-and-punishments/" target="_blank" rel="noreferrer noopener">amygdala</a> - the part of the brain that helps process emotions and motivation - play a crucial role in managing hunger and thirst.



<h2 class="wp-block-heading" id="h-brain-links-emotion-with-thirst-and-hunger">Brain links emotion with thirst and hunger</h2>



The amygdala is often tied to emotions like fear, pleasure, and <a href="https://www.earth.com/news/brain-cells-communicate-to-support-decision-making/" target="_blank" rel="noreferrer noopener">decision-making</a>. But it turns out that it also affects how much and when we eat and drink. 



Earlier studies from this team showed that neurons in the amygdala link food to emotional experiences. 



Pleasant meals are linked with joy. Nausea reduces appetite. Even an unpleasant meal can build an aversion that sticks.



In those earlier experiments, researchers found they could influence mice behavior by adjusting neuron activity. 



The mice would start eating, even if they were already full or feeling sick, based on how these neurons were manipulated.



<h2 class="wp-block-heading" id="h-hunger-and-thirst-on-separate-tracks">Hunger and thirst on separate tracks</h2>



This latest study takes things further. It shows that different <a href="https://www.earth.com/news/hunger-hormones-in-the-gut-can-change-our-eating-behavior/" target="_blank" rel="noreferrer noopener">sets of neurons</a> in the amygdala respond specifically to either thirst or hunger.



“One of these groups of neurons is solely dedicated to regulating the desire to drink, the first ‘thirst neuron’ that has been identified in the amygdala,” explains Federica Fermani, who led the study. 



“When we activated these neurons, the mice drank more, and when we suppressed their activity, the mice drank less. We also identified another group of neurons in the same region of the amygdala that drives thirst but also plays a role in regulating hunger."



These findings highlight how some neurons show remarkable specialization for specific behaviors, while others have more general roles in guiding food and drink choices.



To observe this, the researchers used tools like optogenetics - a method that uses light to control brain cells. This allowed them to precisely turn certain neurons on or off.



They watched how the mice behaved when thirsty, hungry, or already satisfied. With these tools, they mapped out where these neurons receive their cues and which other parts of the brain they talk to.



<h2 class="wp-block-heading" id="h-neurons-influence-taste-perception">Neurons influence taste perception</h2>



Interestingly, the team also learned that these neurons could influence <a href="https://www.earth.com/news/a-surprising-amount-of-adults-like-intensely-sour-flavors/" target="_blank" rel="noreferrer noopener">taste preferences</a>. 



By linking the activation of certain neurons with a drink the mice didn’t like, they managed to change the animals’ behavior. 



A flavor that had been avoided became one the mice started to choose.



This ability to alter choices with neuron signals gives scientists a new way to look at how emotions, desires, and past experiences shape what we choose to eat and drink. 



Since the structure of the amygdala is similar in humans and mice, the research may help explain human eating patterns too.



“Basic drives like thirst and hunger ensure we eat and drink at the right times, giving our bodies the hydration and nutrition needed to survive,” explains Rüdiger Klein, Director at the Max Planck Institute for Biological Intelligence. 



“But these same neural circuits can also contribute to <a href="https://www.earth.com/news/study-reveals-what-triggers-our-brains-to-overeat/" target="_blank" rel="noreferrer noopener">overeating</a> or undereating, depending on the signals they encounter in the brain."



<h2 class="wp-block-heading" id="h-hunger-thirst-and-the-human-brain">Hunger, thirst, and the human brain</h2>



By uncovering these processes, we gain a better understanding of how the brain emotionally evaluates food and drink, learns to associate them with pleasure or aversion, and how neural development shapes both innate and learned behaviors.



This research raises important questions about how the brain balances multiple needs. 



How does it know when we’ve had enough? What happens when hunger and thirst compete? And how do these systems become disrupted in conditions like obesity, anorexia, or addiction?



As scientists continue to untangle the connections between emotion, memory, and behavior in the brain, studies like this offer a clearer picture of how we make some of our most basic - and most important - choices every day.



The full study was published in the journal <a href="https://www.nature.com/articles/s41467-025-58144-3" target="_blank" rel="noreferrer noopener">Nature Communications</a>.



-----



Like what you read? <a href="https://www.earth.com/subscribe/" target="_blank" rel="noreferrer noopener">Subscribe to our newsletter</a> for engaging articles, exclusive content, and the latest updates.&nbsp;



Check us out on <a href="https://www.earth.com/earthsnap/" target="_blank" rel="noreferrer noopener">EarthSnap</a>, a free app brought to you by <a href="https://www.earth.com/author/eralls/" target="_blank" rel="noreferrer noopener">Eric Ralls</a> and Earth.com.



-----

How our brains tell us when we need to eat or drink

The brain plays a central role in guiding us to...

Scientists are transforming chocolate into a functional food by infusing it with probiotics and prebiotics, aiming to create a treat that satisfies cravings while supporting gut health. 



The challenge lies in maintaining chocolate's beloved texture and flavor while adding health benefits.



<figure class="wp-block-embed aligncenter is-type-video is-provider-youtube wp-block-embed-youtube wp-embed-aspect-16-9 wp-has-aspect-ratio"><div class="wp-block-embed__wrapper">
https://youtu.be/Ug657J67iEo?si=w96YjGMsg939LD_3
</div></figure>



Probiotics - beneficial microbes that balance gut bacteria and aid digestion - are typically fragile and can be destroyed by stomach acid or processing. 



Prebiotics act as food for these microbes, helping them thrive. Together, they form "synbiotics," a powerful health combination.



Researchers Smriti Gaur and Shubhi Singh from India's Jaypee Institute of Information Technology took an innovative approach, using natural prebiotics like corn and honey instead of complex processing methods. 



They created five chocolate varieties: a control and four synbiotic versions containing different combinations of prebiotics, probiotics (Lactobacillus strains), and flavor enhancers (cinnamon or orange).



Laboratory simulations of human digestion showed the probiotics remained viable for over five hours, suggesting they could survive long enough to benefit gut health.



Taste tests were positive, with researchers particularly enjoying the orange-flavored variety, describing it as having "vibrant citrus notes" complementing the "rich cocoa" with a "luxurious" texture.



This research represents just the beginning. With further refinement of strains, textures, and flavors, chocolate could evolve beyond mere indulgence to become a functional food that nourishes while it delights.



The study is published in the journal <a href="https://pubs.acs.org/doi/10.1021/acsfoodscitech.4c00741" target="_blank" rel="noreferrer noopener">ACS Food Science &amp; Technology</a>.

Is chocolate the next nutritional powerhouse?

Scientists are transforming chocolate into a functional food by infusing...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="0ynNMYkMKa-2340414-12187" type="single"]</div>



Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Nushagak Bay, a large estuary in southwest Alaska. Nushagak runs mainly north to south and exits in Bristol Bay, a large body of water in the Bering Sea.



"The bay is primarily fed by the Nushagak River, which begins in the Alaska Range and flows southwest approximately 450 km. The bay is also fed by several additional rivers including the Wood, Igushik, Snake and Weary rivers," says ESA.



"The dark colors of the Nushagak River are most likely due to tannins or lignins (chemical substances found in plants). Tannins and lignins from roots, leaves, seeds, bark and soil can leach into the water and give it a brown or even black colour. The sediments then flow southwards where it is mixed with the bluer waters of the bay."



Video/ Image Credit: ESA



---



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

Nushagak Bay in southwest Alaska

[sendtonews key="0ynNMYkMKa-2340414-12187" type="single"] Today’s Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"]</div>



Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> (ACS) reveals that proteins on flu viruses are actually flexible, tilting and waving in a “breath-like” motion. According to the experts, these proteins could be used to better defend against the flu.



"The main antigenic targets of influenza virus are two surface glycoproteins, hemagglutinin (HA) and neuraminidase (NA). Whereas the structural and dynamical properties of both glycoproteins have been studied previously, the understanding of their plasticity in the whole-virion context is fragmented," wrote the researchers.



To investigate, the team conducted detailed simulations of the influenza A H1N1 virion, or the swine flu. The experts concluded that the visualizations show many new vulnerable states of flu viruses, which could improve future vaccines and antiviral drugs.



Video/ Image Credit: American Chemical Society&nbsp;



---



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Flu viruses are more flexible than expected

[sendtonews key="G9bUoxcjr4-2511624-12187" type="single"] Today's Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="3upvlAaHgO-2256633-12187" type="single"]</div>



Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Lake Trasimeno, which is located west of Perugia in central Italy. It is the fourth largest lake in the country. While Trasimeno’s water level varies, it has a maximum depth of approximately six meters.&nbsp;



"In this Copernicus Sentinel-2 image, captured on 6 August 2022, the lake’s emerald green colour is likely due to the presence of phytoplankton. Streaks in the water, particularly visible in the west, indicate the presence of soil and sediments which have been stirred up by winds. Dark colored waters in the southern part of the lake indicate a presence of submerged and floating macrophytes (aquatic plants) as well as algae," says ESA.



"Surrounded by hills on three sides, Trasimeno is subject to heavy storms created by winds, especially from the north and west. There are three islets in the lake: Maggiore, Minore and Polvese (the largest). The lake’s shores are sparsely inhabited with only two popular villages: Castiglione del Lago and Passignano sul Trasimeno."



"Italy is experiencing its worst drought in 70 years which has affected drinking water supplies, hydroelectric power and agricultural production. High temperatures, hot winds and lack of rainfall are the main causes of drought in the Umbrian region which saw Lake Trasimeno’s drop 1.3 m, reaching the limit of the hydrometric zero in July 2022."



Video/Image Credit: ESA&nbsp;



---



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

Lake Trasimeno in Central Italy

[sendtonews key="3upvlAaHgO-2256633-12187" type="single"] Today’s Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="LvS8v8bp9z-2564889-12187" type="single"]</div>



Today's Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> describes a new self-powered nanosensor that can instantly detect mercury contamination with the tap of a finger.&nbsp;



The oxidized form of mercury can be harmful when it is ingested through contaminated water or food. This makes it necessary for experts to develop sensors that can quickly and accurately detect the presence of mercury.&nbsp;



Zong-Hong Lin and colleagues have now created a triboelectric nanosensor (TENS) that can detect mercury by simply by touching a sample. According to the researchers, their TENS could serve as the basis for similar devices to safely and remotely monitor other pollutants.



Video Credit: American Chemical Society&nbsp;



---



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Detecting mercury contamination with the tap of a finger

[sendtonews key="LvS8v8bp9z-2564889-12187" type="single"] Today's Video of the Day from the...

<div class="wp-block-sendtonews-playerselector">[sendtonews key="iuA5mpp3jv-1641775-12187" type="single"]</div>



Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Kainji Lake, a reservoir on the Niger River.



In 1968, Kainji Lake was created by the construction of the Kainji Dam. The Niger River, the third longest in Africa, enters the lake in the north.&nbsp;



According to <a href="https://www.earth.com/news/rivers-in-the-american-west-are-a-lifesaving-resource-for-birds/">ESA</a>, the creation of the lake submerged Foge Island and the town of Bussa and permanently flooded other riverine settlements, leaving around 50,000 people displaced.&nbsp;



Large parts of Foge Island are temporarily exposed during low water tides, and the land is often used by migrating fishermen. Kainji Dam is a dam across the Niger River in Niger State of Central Nigeria. 



Wild mammals occur at relatively low densities due to illegal hunting. Lake Kainji has suffered a dramatic decline as a fishery due to the high numbers of artisanal and subsistence fisherfolk using the lake. It has been suggested that a period of closure, together with controlled fishing rights may help improve fish stocks.



Kainji Lake National Park is the oldest of its kind in Nigeria. The park contains three distinct areas: a part of the Kainji Lake, the Borgu Game Reserve to the west of the lake, and the Zugurma Game Reserve to the southeast. The park is home to around 65 mammal species, 350 bird species, and 30 species of reptiles and amphibians. 



Video/ Image Credit: European Space Agency&nbsp;



---



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



Check us out on <a href="https://www.earth.com/earthsnap/">EarthSnap</a>, a free app brought to you by Eric Ralls and Earth.com.

Kainji Lake in north central Nigeria

[sendtonews key="iuA5mpp3jv-1641775-12187" type="single"] Today’s Video of the Day from the...

Sawtooth National Forest&nbsp;is a&nbsp;National Forest&nbsp;that covers 2,110,408 acres (854,052 ha) in the&nbsp;U.S. states&nbsp;of&nbsp;Idaho&nbsp;(~96 percent) and&nbsp;Utah&nbsp;(~4 percent). Managed by the&nbsp;U.S. Forest Service&nbsp;in the&nbsp;U.S. Department of Agriculture. Sawtooth National Forest offers facilities for recreation, with four ski areas,&nbsp;whitewater&nbsp;and&nbsp;flatwater&nbsp;boating, hunting, 81 campgrounds, and over 1,000&nbsp;mi (1,600&nbsp;km) of trails and roads for&nbsp;hiking,&nbsp;mountain biking, and&nbsp;all-terrain vehicle&nbsp;use, including two&nbsp;National Recreation Trails.&nbsp;



Sawtooth offers cabins, campgrounds, and dispersed camping. See the US Forest Service for more information.&nbsp;

Sequoia and Kings Canyon National Parks, California

News coming your way