Today's Image of the Day from the European Space Agency features a false-color radar depiction of central Ethiopia.



According to ESA, the photograph is a blend of multiple Sentinel-1 images from spring, summer and autumn 2023, which have been overlaid to create this single image.



“Radar images capture surface texture rather than reflected light so they are naturally black and white but here images from each season have been assigned a different color: red, green and blue respectively,” explained <a href="https://www.esa.int/" target="_blank" rel="noreferrer noopener">ESA</a>.



“When the images are combined, the different colors reveal variations that occurred in the different seasons.”



<h2 class="wp-block-heading" id="h-rugged-terrain-of-central-ethiopia-nbsp">Rugged terrain of central Ethiopia&nbsp;</h2>



ESA noted that Ethiopia’s terrain is one of the most rugged in Africa. The landscape is primarily characterized by highlands and plateaus.&nbsp;



The Ethiopian Highlands, also known as the Roof of Africa, dominate this region and include some of the highest peaks in Africa, such as Ras Dashen. The terrain features steep escarpments, deep valleys, and numerous rivers.&nbsp;



The central part of the country is also home to the Great Rift Valley, which runs through Ethiopia and includes a series of lakes and volcanic mountains. This region's varied topography contributes to its rich biodiversity and distinct climate zones.



<h2 class="wp-block-heading" id="h-lakes-of-central-ethiopia-nbsp">Lakes of central Ethiopia&nbsp;</h2>



According to ESA, water bodies appear dark in this image because flat water surfaces reflect the radar signal away from the satellite. “The various colors visible in some lakes are due either to the changing surface currents and sediments from rivers or to variations in water level.”



Lake Ziway is one of the largest <a href="https://www.earth.com/news/africas-flamingos-at-risk-due-to-rising-lake-levels/" target="_blank" rel="noreferrer noopener">lakes</a> in the region. It is located about 160 kilometers south of Addis Ababa, the capital of Ethiopia.&nbsp;



The lake is known for its rich bird diversity, including large populations of pelicans, cormorants, and herons. Lake Ziway also supports local fishing communities.



Lake Shala is the deepest lake in the Ethiopian Rift Valley and is known for its volcanic origins. It has a maximum depth of 266 meters and is surrounded by hot springs and steep, rocky cliffs.



<h2 class="wp-block-heading" id="h-climate-of-central-ethiopia-nbsp">Climate of central Ethiopia&nbsp;</h2>



Central Ethiopia features a diverse climate, primarily influenced by its elevation and geographical location within the tropics.



<h3 class="wp-block-heading" id="h-highland-climate">Highland climate</h3>



Much of central Ethiopia consists of highlands, with elevations ranging from 1,500 to over 3,000 meters above sea level. These highlands experience a temperate climate, with cooler <a href="https://www.earth.com/news/temperatures-in-africa-are-rising-above-levels-that-rhinoceros-can-tolerate/" target="_blank" rel="noreferrer noopener">temperatures</a> compared to the lowlands.&nbsp;



The average temperatures range from 50 to 68 degrees Fahrenheit. The higher elevations, such as those found in the Ethiopian Highlands, can experience temperatures that are close to freezing at night.



<h3 class="wp-block-heading" id="h-rainy-seasons">Rainy seasons</h3>



Central Ethiopia has two main rainy seasons. The primary rainy season, known as the "Kiremt," occurs from June to September and brings the majority of the annual rainfall.&nbsp;



The "Belg," or short rainy season, occurs from March to May. The rainfall during these periods supports agriculture, which is a key part of the region's economy.



<h3 class="wp-block-heading" id="h-dry-season">Dry season</h3>



The <a href="https://www.earth.com/news/africas-wet-forests-have-seen-an-alarming-rise-in-wildfires/" target="_blank" rel="noreferrer noopener">dry season</a>, known as the "Bega," spans from October to February.&nbsp;During this time, the region experiences significantly less rainfall, and the weather tends to be sunny and dry. 



<h2 class="wp-block-heading" id="h-culture-of-central-ethiopia-nbsp">Culture of central Ethiopia&nbsp;</h2>



The <a href="https://www.earth.com/news/humans-are-not-the-only-animals-that-create-their-own-culture/" target="_blank" rel="noreferrer noopener">culture</a> of central Ethiopia is a dynamic blend of ancient traditions and modern influences. This culture is characterized by a strong sense of community and a profound connection to the region's historical and spiritual roots.



The Amhara people have played a significant role in the cultural and political life of central Ethiopia. The Amhara are known for their rich heritage, which includes the Amharic language, a Semitic tongue that serves as one of the country's official languages.



Orthodox Christianity is a key aspect of central Ethiopian culture, particularly among the Amhara and other highland communities.&nbsp;



This part of East Africa is also known for its traditional music and dance, which reflect the region's historical depth and cultural diversity.&nbsp;



The cuisine of central Ethiopia is another significant cultural aspect, with injera (a spongy flatbread made from teff) being a staple food.&nbsp;Injera is typically served with a variety of stews (wats) and salads.



The communal eating experience, where meals are shared from a single large plate, emphasizes the importance of community and togetherness.



Image Credit: ESA&nbsp;



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The vibrant seasons of central Ethiopia

Today's Image of the Day from the European Space Agency features a false-color radar depiction of central Ethiopia. According to ESA, the photograph is a blend of multiple Sentinel-1 images from spring, summer and autumn 2023, which have been overlaid to create this single image. “Radar images capture surface texture rather than reflected light so they are naturally black and white but here images from each season have been assigned a different color: red, green and blue respectively,” explained ESA. “When the images...

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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



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



Spiral galaxies are classified into different types based on the tightness of their spirals and the size of their central bulge, with classifications ranging from tightly wound arms in Sa galaxies to more loosely wound arms in Sc galaxies. The <a href="https://www.earth.com/news/large-amount-of-dark-matter-may-be-missing-from-the-milky-way/" target="_blank" rel="noreferrer noopener">Milky Way</a>, our home galaxy, is a prime example of a spiral galaxy.



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



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



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



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



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



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



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Spiral galaxy NGC 6744 in the constellation Pavo

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

A very snowy Québec City, Canada's seventh largest city, is seen here in today’s Image of the Day from the <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a>. Québec City is often referred to as the “most European city in North America” and is the one of the oldest continuously inhabited cities on the continent. This image was captured by the Operational Land Imager (OLI) on board the <a href="https://www.earth.com/video/the-landsat-legacy-continues/">Landsat 8 satellite</a>.

Winter and Snow in Québec City

A very snowy Québec City, Canada's seventh largest city, is...

Melting tropical glaciers in Indonesia are seen here in today’s Image of the Day comes from the <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> and features a look at melting tropical glaciers in New Guinea, part of the Papua province of <a href="https://www.earth.com/news/reconstruction-tsunami-social-divide/">Indonesia</a>. This image was captured by the Operational Land Imager (OLI) on board the Landsat 8 satellite.

Melting Tropical Glaciers in Indonesia

Melting tropical glaciers in Indonesia are seen here in today’s...

The Cotahuasi Canyon in Peru is seen here in today’s Image of the Day from the <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> . The Cotahuasi Canyon is one of the deepest in the world, measuring 1.5 to 2.2 miles deep, and formed over the course of millions of years as rivers and <a href="https://www.earth.com/news/melting-glaciers-ocean-floor/">glaciers</a> eroded the plateau. This image was captured by the Operational Land Imager (OLI) on board the Landsat 8 satellite.

The Cotahuasi Canyon in Peru

The Cotahuasi Canyon in Peru is seen here in today’s...

Eastern Andes mountains and their smoky canyons are captured in this Image of the Day from the <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a>. The smoke is coming from several <a href="https://www.earth.com/news/plant-and-pollinator-connections-become-stronger-after-wildfires/">wildfires</a> in the upper part of the Yungas forests, which appear dark green due to the wet and cloudy conditions. Also visible in the lower left part of the image is Lake Titicaca.<ins class="adsbygoogle" style="display: block; text-align: center;" data-ad-layout="in-article" data-ad-format="fluid" data-ad-client="ca-pub-2900029420000674" data-ad-slot="3505321548"></ins>

Eastern Andes Mountains

Eastern Andes mountains and their smoky canyons are captured in...

This Image of the Day comes from the <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> and features a look at orange snow in eastern Europe. The snow has been tinted orange. Orange snow in eastern Europe shown in image above. Strong winds kicked up large amounts of dust from the <a href="https://www.earth.com/news/snow-falls-sahara-desert/">Sahara Desert</a>, turning the snow a slight orange color.

Orange snow in eastern Europe

This Image of the Day comes from the NASA Earth...

Today’s Image of the Day comes from the <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> and features a look at several coastlines along the southern <a href="https://www.earth.com/image/blooming-baltic-sea/">Baltic Sea</a>.

Featured in the photo are the coasts of Denmark, Sweden, Norway, Poland, Russia, and Lithuania.

This image was captured by an astronaut on board the International Space Station just as the sun was setting along the North Sea.

The Baltic Sea is a mediterranean sea of the Atlantic Ocean, enclosed by Denmark, Estonia, Finland, Latvia, Lithuania, Sweden, northeast Germany, Poland, Russia and the North and Central European Plain.
The sea stretches from 53°N to 66°N latitude and from 10°E to 30°E longitude. A marginal sea of the Atlantic, with limited water exchange between the two water bodies, the Baltic Sea drains through the Danish Straits into the Kattegat by way of the Øresund, Great Belt and Little Belt. It includes the Gulf of Bothnia, the Bay of Bothnia, the Gulf of Finland, the Gulf of Riga and the Bay of Gdańsk.
The Baltic Proper is bordered on its northern edge, at the latitude 60°N, by the Åland islands and the Gulf of Bothnia, on its northeastern edge by the Gulf of Finland, on its eastern edge by the Gulf of Riga, and in the west by the Swedish part of the southern Scandinavian Peninsula.

--

By <a href="mailto:rarnold@earth.com">Rory Arnold</a>, <a href="http://earth.com/staff">Earth.com</a> Staff Writer

Image Credit: <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a>

Southern Baltic Sea coastlines

Today’s Image of the Day comes from the NASA Earth...

Today’s Image of the Day comes from the <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> and features a look at Pinta Island located in northern end of the Galápagos archipelago.

Although Pinta Island makes up less than one percent of the total <a href="https://www.earth.com/news/galapagos-bird-lost-ability-fly/">Galápagos</a> land area, it holds almost one-third of the total native terrestrial plant species.

This image was captured by the Enhanced Thematic Mapper Plus on board the Landsat 7 satellite.

--

By <a href="mailto:rarnold@earth.com">Rory Arnold</a>, <a href="http://earth.com/staff">Earth.com</a> Staff Writer

Image Credit: <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a>

Pinta Island in the Galápagos

Deforestation in the Gran Chaco plains of South America is seen in today’s Image of the Day comes from the <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a>. About 20 percent of the Gran Chaco plains has fallen victim to <a href="https://www.earth.com/news/tropical-deforestation-songbird-populations/">deforestation</a> since 1985, having mostly been converted into farmland. This image was captured by the Operational Land Imager (OLI) on board the Landsat 8 satellite.

Gran Chaco Plains of South America

Deforestation in the Gran Chaco plains of South America is...

On World Ozone Day, we celebrate global efforts to protect and restore the ozone layer, a vital shield that protects life on Earth from harmful ultraviolet (UV) radiation.&nbsp;



World Ozone Day was established by the United Nations General Assembly in 1994. This occasion highlights the <a href="https://www.earth.com/news/decline-in-ozone-depleting-chemicals-is-an-encouraging-trend/" target="_blank" rel="noreferrer noopener">success</a> of the Montreal Protocol, an international treaty adopted in 1987, which has been instrumental in phasing out the production and use of ozone-depleting substances.&nbsp;



<h2 class="wp-block-heading" id="h-climate-action-on-world-ozone-day-nbsp">Climate action on World Ozone Day&nbsp;</h2>



World Ozone Day is an important reminder of the link between <a href="https://www.earth.com/news/wildfires-threaten-the-recovery-of-the-ozone-layer/" target="_blank" rel="noreferrer noopener">ozone protection</a> and climate action. The phasing out of ozone-depleting chemicals has greatly contributed to reducing greenhouse gas emissions and slowing global warming.



<div class="wp-block-sendtonews-playerselector">[sendtonews key="iO1Qd1FFM1-3858489-12187" type="single"]</div>



“The theme for this year's World Ozone Day (WOD) is Montreal Protocol: Advancing Climate Action. This theme underscores the critical role the Montreal Protocol plays in not only restoring the stratospheric ozone layer but also in mitigating climate change,” noted James Curlin, head of the <a href="https://www.unep.org/node" target="_blank" rel="noreferrer noopener">UNEP</a> Law Division’s OzonAction Branch.



“It serves as a powerful reminder of our collective responsibility to continue and intensify our efforts to fight climate change through any means possible, be it through the phase out of hydrochlorofluorocarbons (HCFCs) and other ozone depleting substances, or through the phase down of hydrofluorocarbons (HFCs).”&nbsp;



“By doing so, we can significantly reduce both the direct and indirect emissions of gases that heat our planet, contribute to the broader goals of climate action, and build a sustainable future for all.”



<h2 class="wp-block-heading" id="h-what-is-ozone-depletion">What is ozone depletion?</h2>



<a href="https://www.earth.com/news/burning-up-of-satellites-severely-harms-ozone-recovery/" target="_blank" rel="noreferrer noopener">Ozone depletion</a> refers to the gradual thinning of the Earth’s ozone layer in the stratosphere. This phenomenon is primarily caused by the release of ozone-depleting chemicals containing gaseous chlorine or bromine from industrial and consumer products.&nbsp;



<h3 class="wp-block-heading" id="h-contributing-factors">Contributing factors</h3>



The most significant contributors are chlorofluorocarbons (CFCs), halons, and other related <a href="https://www.earth.com/news/monsoons-launch-ozone-depleting-substances-into-the-stratosphere/" target="_blank" rel="noreferrer noopener">substances</a>.&nbsp;



When these chemicals are released into the atmosphere, they eventually reach the stratosphere, where ultraviolet (UV) radiation breaks them down, releasing chlorine and bromine atoms.&nbsp;



These atoms then react with ozone (O3) molecules, causing the ozone to break apart into oxygen molecules (O2) and single oxygen atoms, thus depleting the ozone layer.



<h3 class="wp-block-heading" id="h-impacts-of-ozone-depletion">Impacts of ozone depletion</h3>



The depletion of the ozone layer has significant environmental and health impacts.&nbsp;



A thinner ozone layer allows more harmful UV-B radiation to reach the Earth’s surface, which can lead to an increase in skin cancers, cataracts, and other health issues.&nbsp;



Ozone depletion also affects ecosystems, particularly marine life, as increased <a href="https://www.earth.com/news/antarctic-ozone-hole-exposes-wildlife-to-harmful-uv-radiation/" target="_blank" rel="noreferrer noopener">UV radiation</a> can harm phytoplankton, the base of the marine food web.



<h2 class="wp-block-heading" id="h-success-of-the-montreal-protocol-nbsp">Success of the Montreal Protocol&nbsp;</h2>



As we celebrate the success of the Montreal Protocol, we must recognize the need to address ongoing environmental threats.&nbsp;



Hydrofluorocarbons (HFCs) are chemicals that were introduced as replacements for ozone-depleting substances like chlorofluorocarbons (CFCs).



However, despite their ozone-friendly nature, HFCs have a global warming potential (GWP) that can be hundreds to thousands of times greater than carbon dioxide.&nbsp;



Recognizing this issue, the Kigali Amendment to the Montreal Protocol, adopted in 2016, was created to phase down the production and use of HFCs. This amendment aims to reduce the use of HFCs and minimize their impact on global warming, while maintaining the protection of the ozone layer.



<h2 class="wp-block-heading" id="h-international-cooperation-on-world-ozone-day-nbsp">International cooperation on World Ozone Day&nbsp;</h2>



World Ozone Day is also a celebration of international cooperation, as nations across the globe have united to tackle a major environmental threat.&nbsp;



The progress in healing the ozone layer shows how collective action can address global challenges.&nbsp;



“At a time when multilateralism is under severe strain, the Montreal Protocol to help protect the ozone layer stands out as a powerful symbol of hope.&nbsp; It is a reminder that when countries show political resolve for the common good, change is possible,” said UN Secretary-General António Guterres.



“In uniting the world to phase out the consumption and production of different ozone depleting substances, the Protocol has also contributed to shielding carbon sinks, protecting humanity’s health and avoiding economic losses.”



“On this World Ozone Day, let’s commit to making peace with our planet. Let’s commit to build on the success of the Montreal Protocol to show what international cooperation at its best can achieve.”



Video Credit: Ozone Secretariat



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World Ozone Day 2024: Advancing climate action

On World Ozone Day, we celebrate global efforts to protect...

Scientists have recently discovered an important control circuit involved in swallowing food. The study has shown that fly larvae have special receptors in their esophagus which are triggered as the insect swallows something.&nbsp;



This leads to the release of <a href="https://www.earth.com/news/serotonin-expedite-learning-process/" target="_blank" rel="noreferrer noopener">serotonin</a>, a messenger substance that is frequently referred to as the “feel-good hormone.” The release of serotonin ensures that the larva continues to eat. 



Although the study focused on flies, the experts argue that humans may also have a similar control circuit.&nbsp;



<h2 class="wp-block-heading" id="h-swallowing-food-makes-you-want-more-nbsp">Swallowing food makes you want more&nbsp;</h2>



Imagine you're sitting in a restaurant, feeling hungry, with a delicious pizza in front of you. Its irresistible aroma fills the air.&nbsp;



You take a bite, savor the flavor as you chew, and the moment you swallow, a wave of satisfaction hits you: Wow, that was amazing! Without hesitation, you reach for another slice and eagerly take another bite.



While the pizza’s smell and taste motivate you to begin eating, it is the pleasurable feeling you have after <a href="https://www.earth.com/news/cane-toads-swallow-their-tongue-when-they-eat/" target="_blank" rel="noreferrer noopener">swallowing</a> which is responsible for you continuing to eat. 



“But how exactly does this process work? Which neural circuits are responsible? Our study has provided an answer to these questions,” said Michael Pankratz, an expert in life and medical sciences at the <a href="https://www.uni-bonn.de/en/" target="_blank" rel="noreferrer noopener">University of Bonn</a>.



<h2 class="wp-block-heading" id="h-neurons-communicate-with-the-digestive-system-nbsp">Neurons communicate with the digestive system&nbsp;</h2>



The study was focused on the larvae of the <a href="https://www.earth.com/news/fruit-fly-smell/" target="_blank" rel="noreferrer noopener">fruit fly</a> Drosophila, which have from 10,000 to 15,000 nerve cells - a manageable number compared to the 100 billion nerve cells in the human brain. 



However, these 15,000 nerve cells form a highly complex network, with every neuron having branching projections through which it contacts dozens or even hundreds of other neurons.



“We wanted to gain a detailed understanding of how the <a href="https://www.earth.com/news/healthy-humans-have-shockingly-different-digestive-systems/" target="_blank" rel="noreferrer noopener">digestive system</a> communicates with the brain when consuming food,” Pankratz said. 



“In order to do this, we had to understand which neurons are involved in this flow of information and how they are triggered.”&nbsp;



<h2 class="wp-block-heading" id="h-an-activated-network-of-neurons">An activated network of neurons</h2>



The scientists investigated not just the paths of all of the nerve fibers in the fruit fly larvae but also the connections between neurons.&nbsp;



To do this, they cut a larva into thousands of very thin slices and photographed them under an electron microscope.



“We used a high-performance computer to create three-dimensional images from these photographs,” Pankratz explained.&nbsp;



Next, project assistants Andreas Schoofs and Anton Miroschnikow analyzed how all these nerve cells are connected to one another.



<h2 class="wp-block-heading" id="h-detecting-food-quality-while-swallowing-nbsp">Detecting food quality while swallowing&nbsp;</h2>



The investigation helped the researchers identify what they called a “stretch receptor” in the esophagus that is wired to a cluster of six neurons in the larva’s brain which can produce serotonin, the “feel-good hormone” ensuring that we feel rewarded for certain actions.



The serotonin-releasing neurons receive new information about what the fly has just swallowed.&nbsp;



“They can detect whether it is food or not and also evaluate its quality,” Schoofs explained. “They only produce serotonin if good quality food is detected, which in turn ensures that the larva continues to eat.”



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



The scientists believe that this fundamental mechanism most likely also exists in humans, and, when defective, it could lead to eating disorders such as anorexia or <a href="https://www.earth.com/news/binge-eating-linked-to-a-specific-set-of-brain-cells/" target="_blank" rel="noreferrer noopener">binge eating</a>. 



Thus, the results of this study might also have implications for the treatment of such disorders.&nbsp;



“But we don’t know enough at this stage about how the control circuit in humans actually works.There is still years of research required in this area,” Pankratz cautioned.



<h2 class="wp-block-heading" id="h-food-swallowing-in-mammals">Food swallowing in mammals</h2>



The study authors noted that serotonin signaling has been implicated in motor function in the mammalian esophagus as well.



“The human esophagus also has distinct regions, with a proximal striated muscle region that is mainly controlled by motor neurons in the brainstem and a distal smooth muscle region that is controlled by central neurons in the medulla oblongata and peripheral neurons of the myenteric plexus.”&nbsp;



The researchers concluded that, despite the differences in the number of cell types as compared with the fly, it would be interesting to see if serotonin also monitors the completion of a biologically meaningful action such as swallowing or other vital activities in mammals.



The study is published in the journal <a href="http://dx.doi.org/10.1016/j.cub.2024.08.025" target="_blank" rel="noreferrer noopener">Current Biology</a>.



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Swallowing food triggers ‘feel-good hormones’

Scientists have recently discovered an important control circuit involved in...

Have you ever thought about the role your home and office heating and cooling systems play during climate change? If your answer is no, you are not alone. Most of us don't. 



We are amusingly oblivious that the warm air we so much enjoy during winters and the cool breeze we desire in hot summers have a tiny part to contribute to the global climate. 



It's time to focus on urban microclimates -- a fascinating yet overlooked aspect of climate change. The mundane <a href="https://www.earth.com/news/rising-sea-levels-threaten-groundwater-global-cities-underground-infrastructure/" target="_blank" rel="noreferrer noopener">city infrastructure</a> we interact with daily can significantly alter local climates and eventually our beloved globe.



It's like throwing a tiny stone in a pond. The ripples may start small, but they grow larger, affecting a much wider area than the stone's initial impact.



<h2 class="wp-block-heading" id="h-heating-and-cooling-systems-in-cities">Heating and cooling systems in cities</h2>



Leading the pack in this research is the <a href="https://illinois.edu" target="_blank" rel="noreferrer noopener">University of Illinois Urbana-Champaign</a>. Under the stewardship of civil and environmental engineering professor Lei Zhao, the team has been investigating the effects of city-level waste heat from our beloved residential and commercial buildings.



“The heat generated from heating and cooling systems is a substantial part of the total heat generated within urban areas,” Zhao said. 



“These systems generate a lot of heat that is released into the atmosphere within cities, making them hotter and further increasing the demand for indoor cooling systems, which feeds even more heat into local climates.”



Think of these systems as the culprits that release a lot of heat into the <a href="https://www.earth.com/news/2024-is-likely-the-hottest-year-in-recorded-history/" target="_blank" rel="noreferrer noopener">city's atmosphere</a>, making it uncomfortably hot and thereby increasing everyone's demand for cooling systems.



That, my friends, is a classic example of a positive physical feedback loop. As we insist on cooling our spaces, we inadvertently feed more and more heat into local climates. Isn't that a bit counterproductive?



<h2 class="wp-block-heading" id="h-negative-loops-to-polarized-demand">Negative loops to polarized demand</h2>



However, the plot thickens. Zhao and his team also discovered an antagonist to this boiling story -- the negative feedback loop.



With rising temperatures under climate change, it's plausible that people would require less heating during winter months. 



Translated to city scales, less heating use would mean less heat being released into the city atmosphere, leading to less <a href="https://www.earth.com/news/scorching-summer-of-2024-could-make-it-the-hottest-year-on-record/" target="_blank" rel="noreferrer noopener">warming</a>.



But don't get too comfy just yet. "This process forms a negative physical feedback loop that may dampen the heating demand decrease. But it does not by any means cancel out the positive feedback loop effect," Zhao warns. 



The team's model hints at a potential polarization of seasonal electricity demand that could unravel a unique set of challenges requiring careful planning.



<h2 class="wp-block-heading" id="h-feedback-loops-of-heating-and-cooling-systems">Feedback loops of heating and cooling systems</h2>



The team, led by Zhao, includes experts from various fields. Zhao is part of the <a href="https://sustainability.illinois.edu/" target="_blank" rel="noreferrer noopener">Institute for Sustainability, Energy, and Environment</a>. He also works with the National Center for Supercomputing Applications and the <a href="https://giesbusiness.illinois.edu/" target="_blank" rel="noreferrer noopener">Gies College of Business</a> at Illinois.



The team used a hybrid modeling framework to study global urban heating and cooling energy demand. This framework combines dynamic Earth system modeling with machine learning techniques. Their research addresses the effects of climate change, considering variability and uncertainties.



Their mission? To integrate the effects of positive and negative physical feedback loops into energy projections and ultimately lay the groundwork for more comprehensive <a href="https://www.earth.com/news/climate-change-earth-energy-imbalance-temperature-rise/" target="_blank" rel="noreferrer noopener">climate impact assessment</a>, science-based policymaking and coordination on climate-sensitive energy planning.



<h2 class="wp-block-heading" id="h-moving-forward">Moving forward </h2>



Supported by the National Science Foundation (<a href="https://www.nsf.gov/" target="_blank" rel="noreferrer noopener">NSF</a>) and iSEE at the University of Illinois Urbana-Champaign, the team is embarking on another exciting journey. 



They plan on introducing variables like humidity, building materials, and future climate-mitigating efforts into their models to refine energy-demand projections further.



As we move forward, the importance of such research becomes more evident. The in-depth understanding it provides will play a crucial role in shaping our sustainable energy planning for the future.



<h2 class="wp-block-heading" id="h-using-heating-and-cooling-systems">Using heating and cooling systems</h2>



If there's one thing to take away from this deep dive, it's this -- every action matters. The way we cool or heat our spaces today might seem insignificant in the larger picture of climate change, but remember the ripples.



Unseen to the eye, these ripples are expanding in the form of local microclimates. The way we plan our cities, consume energy, and mitigate climate impacts can either create ripples of problems or waves of sustainable solutions.



The choice, as always, is ours.



So next time you adjust your thermostat on the heating or cooling systems, take a moment to think - "What ripple am I creating?".



The study is published in the journal <a href="https://dx.doi.org/10.1038/s41558-024-02108-w" target="_blank" rel="noreferrer noopener">Nature Climate Change</a>.



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Indoor heating and cooling systems affect city temperatures

Have you ever thought about the role your home and...

Rapa Nui, also known as Easter Island or Te Pito o Te Henua (the navel of the world), is one of the most remote inhabited locations on Earth, situated over 1,900 km from the nearest Polynesian island and 3,700 km from South America.&nbsp;



<h2 class="wp-block-heading" id="h-biggest-mysteries-of-easter-island-nbsp">Biggest mysteries of Easter Island&nbsp;</h2>



Despite extensive study by archaeologists, anthropologists, and geneticists, two central aspects of Rapa Nui’s history remain controversial.



The first contentious topic is the theory of Easter Island's population collapse due to “ecocide” or environmental mismanagement.



The second debate centers around whether the Polynesian ancestors of the Rapanui people had contact with Indigenous Americans before European arrival in 1722.



<h2 class="wp-block-heading" id="h-new-clues-in-easter-island-remains">New clues in Easter Island remains</h2>



A new study published in the journal <a href="https://dx.doi.org/10.1038/s41586-024-07881-4" target="_blank" rel="noreferrer noopener">Nature</a> examines the genomes of 15 Rapanui individuals who lived between 1670 and 1950.&nbsp;



The remains from Easter Island, housed in the Musée de l'Homme in Paris, were analyzed by an international team of scientists, including assistant professor Víctor Moreno-Mayar from the <a href="https://www.ku.dk/english/" target="_blank" rel="noreferrer noopener">University of Copenhagen</a> and researchers from institutions across Europe, the U.S., Chile, and Rapa Nui itself.&nbsp;



The study sheds light on both the ecocide theory and the possibility of transpacific contact.



<h2 class="wp-block-heading" id="h-a-cautionary-tale">A cautionary tale</h2>



For many years, the story of Rapa Nui has been used as a cautionary tale of <a href="https://www.earth.com/news/biodiversity-loss-can-lead-to-total-ecosystem-collapse/" target="_blank" rel="noreferrer noopener">ecological collapse</a>. After the island was settled by Polynesians around 1250, its landscape dramatically transformed.&nbsp;



The famous moai statues were constructed, and the once-lush forests, particularly palm trees, disappeared by the 1600s.&nbsp;



According to the “ecocide” hypothesis, the environmental changes were triggered by a growing population of over 15,000 people, leading to resource depletion, warfare, famine, and even cannibalism, which ultimately caused a catastrophic population collapse.



<h2 class="wp-block-heading" id="h-easter-island-population-was-surprisingly-stable">Easter Island population was surprisingly stable</h2>



However, the new genetic study challenges this narrative. The researchers expected to find signs of a sudden population decline in the genomes of ancient Rapanui individuals, but their analysis showed no such genetic evidence.&nbsp;



Study co-author Bárbara Sousa da Mota is a researcher at the <a href="https://www.unil.ch/central/en/home.html" target="_blank" rel="noreferrer noopener">University of Lausanne</a>.



“Our genetic analysis shows a stably growing population from the 13th century through to European contact in the 18th century. This stability is critical because it directly contradicts the idea of a dramatic pre-contact population collapse,” said Sousa da Mota.



The study illustrates the resilience of the Rapanui population in adapting to environmental changes, suggesting that the real disruptions came with <a href="https://www.earth.com/news/blue-antelope-hippotragus-leucophaeus-extinction-caused-european-colonization/" target="_blank" rel="noreferrer noopener">European colonial activity</a> after 1722.



<h2 class="wp-block-heading" id="h-settling-a-long-debate">Settling a long debate</h2>



Another long-debated topic is whether the Polynesian ancestors of the Rapanui reached the Americas before European arrival.&nbsp;



Despite previous studies rejecting the possibility of such contact, the new research paints a different picture.&nbsp;



By generating high-quality ancient genomes, the researchers discovered that around ten percent of the Rapanui gene pool has Indigenous American origins.&nbsp;



More importantly, the team found that this contact likely occurred before European arrival.



<h2 class="wp-block-heading" id="h-distribution-of-ancient-dna">Distribution of ancient DNA</h2>



Study lead author Víctor Moreno-Mayar is an assistant professor at the University of Copenhagen’s Globe Institute.



“We looked into how the <a href="https://www.earth.com/news/native-american-civilization-cahokia-50000-people-vanished-600-years-ago/" target="_blank" rel="noreferrer noopener">Indigenous American</a> DNA was distributed across the Polynesian genetic background of the Rapanui. This distribution is consistent with a contact occurring between the 13th and the 15th centuries,” explained Moreno-Mayar.



While the study cannot pinpoint where this contact took place, the findings suggest that the ancestors of the Rapanui may have reached the Americas before <a href="https://www.earth.com/news/vikings-landed-in-the-americas-500-years-before-columbus/" target="_blank" rel="noreferrer noopener">Columbus</a>. This could mean that Polynesians undertook even more formidable voyages than previously thought.



<h2 class="wp-block-heading" id="h-challenging-the-narratives-of-easter-island-nbsp">Challenging the narratives of Easter Island&nbsp;</h2>



The new findings challenge longstanding narratives about Easter Island and the potential collapse of its population.&nbsp;



“Personally, I believe the idea of the ecocide is part of a colonial narrative,” said Moreno-Mayar. “The notion that these supposedly primitive people could not manage their resources and almost destroyed themselves is not supported by the genetic evidence.”&nbsp;



“While we must acknowledge that human arrival dramatically altered the ecosystem, there is no evidence of a population collapse before Europeans came. So we can put those ideas to rest now.”



<h2 class="wp-block-heading" id="h-formidable-voyages-across-the-pacific-nbsp">Formidable voyages across the Pacific&nbsp;</h2>



Likewise, the study debunks the idea that Indigenous American genetic ancestry in modern-day Rapanui is solely due to European colonial activity. Instead, it points to earlier interactions between Rapanui and Indigenous American populations.&nbsp;



“We believe this means that Rapanui were capable of even more formidable voyages across the Pacific than previously established,” noted Sousa da Mota.



The research team engaged directly with the Rapanui community, including the “Comisión Asesora de Monumentos Nacionales” (CAMN), to ensure the study addressed questions of interest to both scientists and the islanders.&nbsp;



<h2 class="wp-block-heading" id="h-genetic-revelations-nbsp">Genetic revelations&nbsp;</h2>



One key outcome of these discussions was confirmation that the ancient Rapanui individuals studied are most closely related to the modern-day population of Rapa Nui.



“We have seen that museum archives contain mistakes and mislabels. Now that we have established that these 15 individuals were in fact Rapanui, we know they belong back on the island,” said Moana Gorman Edmunds, an archaeologist from Rapa Nui and co-author of the study.



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



Th study offers significant new insights into Rapa Nui’s history, refuting the ecocide theory and providing evidence of pre-European contact between Rapanui and Indigenous Americans.&nbsp;



Moreover, it opens the door to discussions about repatriating the remains of Rapanui ancestors and preserving their legacy for future generations.



The Rapanui community, through CAMN, will also retain control over who has access to the genetic data of their ancestors and how it is used.



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Easter Island DNA proves the population did not collapse 

Rapa Nui, also known as Easter Island or Te Pito...

NOAA Warning: "Strong" solar storms and auroras expected today

Update -- September 16, 2024, 09:06 AM Eastern Time The...

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



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



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



Video/ Image Credit: ESA



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

Nushagak Bay in southwest Alaska

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

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



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



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



Video/ Image Credit: American Chemical Society&nbsp;



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



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

Flu viruses are more flexible than expected

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

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



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



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



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



Video/Image Credit: ESA&nbsp;



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

Lake Trasimeno in Central Italy

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