Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA Earth Observatory</a> features the reddish-brown waters of the Betsiboka River Delta in Madagascar. It is one of the most visually striking river deltas in the world, especially when viewed from space.



The Betsiboka River is the largest river in Madagascar by discharge, and its delta is equally significant. The river flows into Bombetoka Bay, which further leads to the Mozambique Channel.



One of the most notable characteristics of the Betsiboka River Delta is its bright color when viewed from space.



"In this case, the color is caused by the transport of iron-rich sediment. The sediment can clog waterways in the delta’s estuarine environment, but it can also form new islands that become colonized by mangroves. Many other water bodies, such as the reservoir fed by the Jacui River in southern Brazil, are colored by reddish sediment," said NASA.



"Despite their rusty color, these arteries of water are important for biodiversity. Algae and other microorganisms serve as a vital food source for vulnerable bird species, such as the Andean flamingo in the Laguna Colorada. Within the Betisboka River Delta, the estuary provides food, such as seagrasses, to the endangered green turtle and vulnerable dugong, or sea cow."



The photo was captured by an astronaut on the space station on September 30, 2023.



Image Credit: NASA Earth Observatory&nbsp;



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The Betsiboka River Delta in Madagascar

Today's Image of the Day from NASA Earth Observatory features the reddish-brown waters of the Betsiboka River Delta in Madagascar. It is one of the most visually striking river deltas in the world, especially when viewed from space. The Betsiboka River is the largest river in Madagascar by discharge, and its delta is equally significant. The river flows into Bombetoka Bay, which further leads to the Mozambique Channel. One of the most notable characteristics of the Betsiboka River Delta is its bright color...

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/" target="_blank" rel="noreferrer noopener">NASA Earth Observatory</a> features an astronaut view of the northeast coast of Somalia. This region, which borders the Indian Ocean, has a mix of sandy beaches and rugged cliffs



"The detailed image reveals a desert landscape etched by wind and water," said NASA. "Over time, streams have cut canyons into the earth. But streams in this region are ephemeral, making groundwater the main source of fresh water."&nbsp;



"The water table is shallow (wells are typically drilled less than 20 meters deep) and meets the surface toward the coast, creating springs."



"Bidirectional winds sculpted the tan, brown, and reddish sand into transverse sand dunes visible near the stream’s deltas. The orientation of the sand dunes indicates that they were likely formed by summer winds blowing up the coast from the southwest."



The economy of northeast Somalia is primarily based on fishing, livestock, and trade. The long coastline provides ample opportunities for fishing, which is a significant source of food and income.



The region is home to important port cities like Bosaso, which is a hub for trade and commerce. These ports are vital for both the local and national economy.



The area is rich in cultural heritage, with a history that dates back to ancient times. It is believed to be part of the ancient Land of Punt, known for its trade relations with ancient Egypt.



The climate is typically hot and dry, with irregular rainfall. This environment shapes the lifestyle and agricultural practices of northeast Somalia.



Despite the arid conditions, the region supports a variety of wildlife, including species adapted to desert and semi-desert habitats.



The photograph was captured on August 9, 2023 as the International Space Station orbited over the Horn of Africa.



Image Credit: NASA Earth Observatory&nbsp;



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Northeast Somalia: A landscape shaped by wind and water

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

Astronaut's remarkable view of Earth Today's Image of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the Earth as it is seen by astronaut Luca Parmitano from the International Space Station.

The photograph was taken from an observatory module on the ISS known as the Cupola, which is Italian for "dome."

Parmitano shared the picture of Earth on social media and wrote: "My first picture from Cupola, since I’ve been back. Reality beats imagination, and once again my words can’t contain the emotion of admiring my planet from orbit... greeted by the Tierra del Fuego." Also Astronaut's remarkable view of Earth

Earth is the third planet from the Sun and the only astronomical object known to harbor life. According to radiometric dating and other evidence, Earth formed over 4.5 billion years ago. Earth's gravity interacts with other objects in space, especially the Sun and the Moon, which is Earth's only natural satellite. Earth orbits around the Sun in 365.256 days, a period known as an Earth sidereal year. During this time, Earth rotates about its axis about 366.256 times.
Earth's axis of rotation is tilted with respect to its orbital plane, producing seasons on Earth. The gravitational interaction between Earth and the Moon causes tides, stabilizes Earth's orientation on its axis, and gradually slows its rotation. Earth is the densest planet in the Solar System and the largest and most massive of the four rocky planets. <a href="https://en.wikipedia.org/wiki/NASA">NASA's</a> view.

--

By <a href="http://csexton@earth">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: European Space Agency

&nbsp;

Astronaut's remarkable view of Earth

Astronaut's remarkable view of Earth Today's Image of the Day...

The Great Green Wall in Africa Today's Image of the Day from the <a href="https://www.esa.int/">European Space Agency</a> shows the progress of the Great Green Wall, a project which will transform the lives of millions of people by restoring degraded land in Africa. 

The initiative aims to plant a line of trees along the border of the African desert, ultimately restoring 100 million hectares of land by 2030. 

Once the project is complete, the wall of trees will be the largest living structure on the planet. It will stretch across 20 countries, sequester 250 million tons of carbon, and create 10 million green jobs.

Since 2007, almost 12 million trees have been planted and 25,000 hectares of land have been restored in Senegal alone.Africa is the world's second-largest and second-most populous continent, after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area and 20% of its land area. With 1.3 billion people as of 2018, it accounts for about 16% of the world's human population. The continent is surrounded by the Mediterranean Sea to the north, the Isthmus of Suez and the Red Sea to the northeast, the Indian Ocean to the southeast and the Atlantic Ocean to the west. The continent includes Madagascar and various archipelagos. It contains 54 fully recognised sovereign states (countries), four territories and two de facto independent states with limited or no recognition. The majority of the continent and its countries are in the Northern Hemisphere, with a substantial portion and number of countries in the Southern Hemisphere. 

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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

Image Credit: European Space Agency

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The Great Green Wall in Africa

The Great Green Wall in Africa Today's Image of the...

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> shows visible changes in the Porong River Delta resulting from an active mud volcano. 

Since 2006, boiling hot mud has been flowing across the island of Java, Indonesia, known as the Lusi mud flow.

Authorities have been diverting excess mud and water off the east coast of Java into the Porong River for more than a decade. 

The increased load of sediment has expanded the river delta and created new space for mangrove forests.

This false-color Landsat satellite image shows the delta on May 10, 2019. The river flows in the eastern area of Java with predominantly tropical<a href="http://www.earth.com/news/sonoran-monsoon-blaming-climate-change/"> monsoon</a> climate (designated as Am in the Köppen-Geiger climate classification). The annual average temperature in the area is 26 °C. The warmest month is October, when the average temperature is around 28 °C, and the coldest is February, at 22 °C. The average annual rainfall is 2473 mm. The wettest month is January, with an average of 426 mm rainfall, and the driest is August, with 20 mm rainfall. Also The Porong River Delta has many bright colors threwout

Porong River is a river flowing through Sidoarjo, East Java, Indonesia, about 700 km east of the capital Jakarta. It is one of the main branches of the Brantas River that discharges into Bali Sea, close to the Madura Strait, and is the main outlet for the Lusi mudflow.

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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

Image Credit: NASA Earth Observatory

The Porong River Delta

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

The Columbia Glacier in southern Alaska. Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features the Columbia Glacier in southern Alaska, which has experienced a long period of rapid retreat followed by a more stable period in recent years. 
Shad O’Neel is a glaciologist at the USGS Alaska Science Center who has been observing the behavior of the Columbia Glacier for many years. 

"The total loss of ice is down substantially,” said O’Neel. “But there is still impressive retreat.”

The glacier has lost more than half of its total thickness and volume since the 1980s. 

This natural color image was captured on June 21, 2019 by the Operational Land Imager on Landsat 8.

--Southeast Alaska, colloquially referred to as the Alaska Panhandle or Alaskan Panhandle, is the southeastern portion of the <a title="U.S. state" href="https://en.wikipedia.org/wiki/U.S._state">U.S. state</a> of <a title="Alaska" href="https://en.wikipedia.org/wiki/Alaska">Alaska</a>, bordered to the east by the northern half of the <a title="Provinces and territories of Canada" href="https://en.wikipedia.org/wiki/Provinces_and_territories_of_Canada">Canadian province</a> of <a title="British Columbia" href="https://en.wikipedia.org/wiki/British_Columbia">British Columbia</a>. The majority of Southeast Alaska's area is part of the <a title="Tongass National Forest" href="https://en.wikipedia.org/wiki/Tongass_National_Forest">Tongass National Forest</a>, the United States' largest <a class="mw-redirect" title="United States National Forest" href="https://en.wikipedia.org/wiki/United_States_National_Forest">national forest</a>. In many places, the <a class="mw-redirect" title="International border" href="https://en.wikipedia.org/wiki/International_border">international border</a> runs along the crest of the <a title="Boundary Ranges" href="https://en.wikipedia.org/wiki/Boundary_Ranges">Boundary Ranges</a> of the <a title="Coast Mountains" href="https://en.wikipedia.org/wiki/Coast_Mountains">Coast Mountains</a> (see <a title="Alaska boundary dispute" href="https://en.wikipedia.org/wiki/Alaska_boundary_dispute">Alaska boundary dispute</a>). The region is noted for its scenery and mild, rainy <a title="Climate" href="https://en.wikipedia.org/wiki/Climate">climate</a>.

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory

&nbsp;

The Columbia Glacier in southern Alaska

The Columbia Glacier in southern Alaska. Today's Image of the...

The glowing remains of a massive star Today's Image of the Day from <a href="https://www.nasa.gov/">NASA</a> features a striking view of the Cygnus Loop nebula, which is a large supernova remnant (SNR) in the constellation Cygnus. The glowing remains of a massive star

The nebula, which is located about 1,500 light-years from our planet, was formed during the explosive death of a massive star about 10,000 - 20,000 years ago.

Hot dust and gas can be seen glowing brightly in this ultraviolet image captured by NASA's Galaxy Evolution Explorer. A supernova remnant (SNR) is the structure resulting from the explosion of a star in a supernova. The supernova remnant is bounded by an expanding shock wave, and consists of ejected material expanding from the explosion, and the interstellar material it sweeps up and shocks along the way.
There are two common routes to a supernova: either a massive star may run out of fuel, ceasing to generate fusion energy in its core, and collapsing inward under the force of its own gravity to form a neutron star or a black hole; or a white dwarf star may accrete material from a companion star until it reaches a critical mass and undergoes a thermonuclear explosion. In either case, the resulting supernova explosion expels much or all of the stellar material with velocities as much as 10% the speed of light (or approximately 30,000 km/s). These speeds are highly supersonic, so a strong shock wave forms ahead of the ejecta. That heats the upstream <a href="http://www.earth.com/news/plasma-rain-sun/">plasma</a> up to temperatures well above millions of K. The shock continuously slows down over time as it sweeps up the ambient medium, but it can expand over hundreds or thousands of years and over tens of parsecs before its speed falls below the local sound speed. 

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA

The glowing remains of a massive star

The glowing remains of a massive star Today's Image of...

Lake St. Clair of the U.S. and Canada Today's Image of the Day from <a href="https://www.nasa.gov/">NASA</a> features Lake St. Clair, which connects Lake Huron to Lake Erie through the St. Clair and Detroit rivers. 

The lake covers an area of about 425 square miles, and has an average depth of 3.5 meters. The United States and Canada both have a deep shipping channel through the lake. 

Canada is a country in the northern part of <a href="http://www.earth.com/news/two-migrations-north-america/">North America</a>. Its ten provinces and three territories extend from the Atlantic to the Pacific and northward into the Arctic Ocean, covering 9.98 million square kilometres (3.85 million square miles), making it the world's second-largest country by total area. Its southern border with the United States, stretching some 8,891 kilometres (5,525 mi), is the world's longest bi-national land border. Canada's capital is Ottawa, and its three largest metropolitan areas are Toronto, Montreal, and Vancouver. Lake St. Clair of the U.S. and Canada also there as shown above in image.
As a whole, Canada is sparsely populated, with most of its land area dominated by forest and tundra. Its population is highly urbanized, with over 80 percent of its inhabitants concentrated in large and medium-sized cities, and 70 percent residing within 100 kilometres (62 mi) of the southern border. Canada's climate varies widely across its vast area, ranging from Arctic climate in the north to hot summers in the southern regions, with four distinct seasons.

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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

Image Credit: NASA

Lake St. Clair of the U.S. and Canada

Lake St. Clair of the U.S. and Canada Today's Image...

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features a view of Florida from the International Space Station (ISS). Astronaut view of the Florida peninsula

The photo highlights the shallow, lightly colored waters surrounding the Florida Keys.

The majority of Florida’s land surface is lying over thick carbonate deposits, which formed the Floridan aquifer system. 

For the most part, sand and clay deposits prevent carbonates from being exposed at the surface. 

In areas where these deposits are thin or non-existent, however, much of the carbonate has dissipated. This results in sinkholes that fill up with groundwater and form lakes. Floridas Spanish pronunciation: [floˈɾiða]) is the southernmost contiguous state in the United States. Astronaut view of the Florida peninsula

The state is bordered to the west by the Gulf of <a href="http://www.earth.com/news/jumbo-squid-declines/">Mexico</a>, to the northwest by Alabama, to the north by Georgia, to the east by the Atlantic Ocean, and to the south by the Straits of Florida. Florida is the 22nd-most extensive (65,755 sq mi or 170,300 km2), the 3rd-most populous (21,477,737 inhabitants),[11] and the 8th-most densely populated (384.3/sq mi or 148.4/km2) of the U.S. states. Jacksonville is the most populous municipality in the state and the largest city by area in the contiguous United States. The Miami metropolitan area is Florida's most populous urban area, with its capital being Tallahassee. 

 --

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory

Astronaut view of the Florida peninsula

Today's Image of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> features Mount Rainier, an active stratovolcano that is located 60 miles southeast of Seattle, Washington. 

At 14,410 feet above sea level, Mount Rainier has 25 named glaciers and stays white year-round.

According to NASA, the mountain is the result of about half a million years of growth during periods of volcanic activity.Mount Rainier (pronounced: /reɪˈnɪər/), also known as Tahoma or Tacoma, is a large active stratovolcano in Cascadia located 59 miles (95 km) south-southeast of Seattle,in Mount Rainier National Park. With a summit elevation of 14,411 ft (4,392 m),it is the highest mountain in the U.S. state of Washington, and of the Cascade Range of the Pacific Northwest, the most topographically prominent mountain in the contiguous United States,  and the tallest in the Cascade Volcanic Arc.
Mt. Rainier is considered one of the most dangerous volcanoes in the world, and it is on the Decade Volcano list. Because of its large amount of glacial ice, Mt. Rainier could produce massive lahars that could threaten the entire Puyallup River valley. "About 80,000 people and their homes are at risk in Mount Rainier’s lahar-hazard zones

--

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Image Credit: NASA Earth Observatory 

&nbsp;

Mount Rainier in Washington

A recent discovery sheds light on the dietary habits of a juvenile tyrannosaur, revealing its last meal to be two baby <a href="https://www.earth.com/news/dinosaurs-self-regulated-their-body-temperature/" target="_blank" rel="noreferrer noopener">dinosaurs</a>. This finding offers a rare glimpse into the life and development of these prehistoric creatures.



In the Alberta Badlands, a hotspot for dinosaur hunters, a remarkable fossil was unearthed in 2009. It was the ribcage of a juvenile gorgosaurus, a close relative of the T. rex.



<h2 class="wp-block-heading" id="h-juvenile-gorgosaurus">Juvenile gorgosaurus</h2>



After meticulous preparation, researchers at the <a href="https://tyrrellmuseum.com/" target="_blank" rel="noreferrer noopener">Royal Tyrell Museum of Palaeontology</a> discovered the remains of two small bird-like dinosaurs, known as citipes, inside the ribcage.



The juvenile gorgosaurus, about seven years old and weighing approximately 330kg, was in a developmental stage equivalent to a human teenager.&nbsp;Its size was roughly a tenth of a fully grown adult tyrannosaur.&nbsp;



<h2 class="wp-block-heading" id="h-dietary-shifts">Dietary shifts</h2>



The presence of the citipes' hind limbs within its ribcage is "solid evidence that tyrannosaurs drastically changed their diet as they grew up,'' according to Dr. Darla Zelenitsky from the <a href="https://www.ucalgary.ca/" target="_blank" rel="noreferrer noopener">University of Calgary</a>.



The findings highlight a significant shift in the feeding habits of tyrannosaurs as they matured.&nbsp;



"We now know that these teenage (tyrannosaurs) hunted small, young dinosaurs," explained Dr. Zelenitsky.&nbsp;



<h2 class="wp-block-heading" id="h-indiscriminate-eaters">Indiscriminate eaters</h2>



Dr. Francois Therrien described these adult tyrannosaurs as "quite indiscriminate eaters." They probably pounced on large prey, "biting through bone and scraping off flesh," he told BBC News.



But, these immature tyrannosaurs were probably not ready to jump into a group of horned dinosaurs, where the adults weighed thousands of kilograms, said Dr. Zelenitsky.



<h2 class="wp-block-heading" id="h-selective-eaters">Selective eaters</h2>



Interestingly, only the legs of the baby dinosaurs were found inside the gorgosaurus. This suggests that the young tyrannosaur was selective, possibly preferring the meatiest parts.



"The rock within the ribcage was removed to expose what was hidden inside," explained Dr. Therrien. "And lo and behold - the complete hind legs of two baby dinosaurs, both under a year old."



Dr. Zelenitsky said that the teenage gorgosaurus seems to have wanted the drumsticks - probably because that's the meatiest part.



"This animal was selecting and even dissecting its prey - biting off the legs and swallowing them whole."



<h2 class="wp-block-heading" id="h-physical-transformations-nbsp">Physical transformations&nbsp;</h2>



As tyrannosaurs grew, they underwent significant physical transformations. Juveniles were lighter and had blade-like teeth, whereas adults developed rounder teeth, dubbed "killer bananas" by Dr. Therrien.&nbsp;



This change in dentition reflects a shift in feeding strategy from selective predation in juveniles to a more powerful and indiscriminate approach in adults.



The discovery provides a window into the lives of these ancient creatures, debunking the stereotype of dinosaurs as mindless monsters.&nbsp;



<h2 class="wp-block-heading" id="h-sophisticated-feeders-nbsp">Sophisticated feeders&nbsp;</h2>



Professor Steve Brusatte, a palaeontologist from the University of Edinburgh, said that seeing prey in the dinosaur's guts gave a real insight into the animals. "They weren't just monsters, they were real, living things and pretty sophisticated feeders."



In the 1993 film Jurassic Park, a giant T. rex chased a car through a fictional theme park. Professor Brusatte noted that an adult T. rex wouldn't have chased after a car - its body was too big, and it couldn't move that fast.



"It would be the youngsters - (like this gorgosaur) - the children of T. rex that you'd have to keep an eye on."



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Juvenile tyrannosaurs hunted baby dinosaurs 

A recent discovery sheds light on the dietary habits of...

View,Of,Brilliant,Green,Aurora,Shining,Over,Swedish,Foggy,Forest

The enchanting auroras, with their vibrant displays of green, red, and purple curtains, have long captivated observers of the night sky. However, the recent emergence of peculiar aurora-like phenomena -- the mauve and white streaks known as "Steve" and their often accompanying glowing green "picket fence" -- has intrigued scientists and sky-watchers alike. 



First identified in 2018 as distinct from the more familiar <a href="https://www.earth.com/news/aurora-borealis-seen-as-far-south-as-the-equator-after-largest-known-solar-storm/" target="_blank" rel="noreferrer noopener">auroras</a>, Steve, named after a character in a 2006 children's movie, and the picket fence phenomenon were initially believed to be products of the same physical processes as the auroras. However, this assumption left many questions unanswered about the origins of their unique glowing emissions.



<h2 class="wp-block-heading" id="h-new-mechanism-is-generating-sky-glows">New mechanism is generating sky glows</h2>



Enter Claire Gasque, a promising graduate student in physics at the <a href="https://www.berkeley.edu/" target="_blank" rel="noreferrer noopener">University of California, Berkeley</a>. Gasque has proposed an intriguing explanation for these phenomena, suggesting a physical mechanism vastly different from those responsible for the traditional auroras.



"This would upend our modeling of what creates light and the energy in the aurora in some cases," Gasque said. "It's really cool, one of the biggest mysteries in space physics right now."



Collaborating with the Space Sciences Laboratory (<a href="https://www.ssl.berkeley.edu/" target="_blank" rel="noreferrer noopener">SSL</a>) at Berkeley, Gasque advocates for a <a href="https://www.nasa.gov" target="_blank" rel="noreferrer noopener">NASA</a> mission to launch a rocket into an aurora to validate her hypothesis. This research coincides with the sun entering a more active phase of its <a href="https://www.earth.com/news/northern-lights-activity-will-intensify-over-the-next-18-months/" target="_blank" rel="noreferrer noopener">11-year cycle</a>, making this an opportune moment for studying rare events like Steve and the picket fence.



<h2 class="wp-block-heading" id="h-distinguishing-steve-from-a-common-aurora">Distinguishing "Steve" from a common aurora</h2>



Gasque's research focuses on the peculiar behavior of electric fields in the upper atmosphere. She suggests that these fields, parallel to <a href="https://www.earth.com/earthpedia-articles/earths-magnetic-field-origin-structure-and-impact-on-humanity/" target="_blank" rel="noreferrer noopener">Earth's magnetic field</a>, might produce the color spectrum observed in the picket fence phenomenon.



This hypothesis challenges existing models of <a href="https://www.earth.com/news/northern-lights-captivated/" target="_blank" rel="noreferrer noopener">auroral light</a> and energy generation and has significant implications for our understanding of the interaction between Earth's magnetosphere and the ionosphere.



Common <a href="https://www.earth.com/news/breathtaking-red-auroras-ignited-northern-hemisphere-skies-this-week/" target="_blank" rel="noreferrer noopener">auroras</a> result from solar wind energizing particles in Earth's magnetosphere, causing oxygen and nitrogen molecules in the upper atmosphere to emit specific frequencies of light. 



Steve, however, exhibits a broad range of frequencies centered around purple or mauve, without the blue light typical of the most energetic particle interactions in auroras. Interestingly, Steve and the picket fence occur at lower latitudes than typical auroras, potentially even near the equator.



<h2 class="wp-block-heading" id="h-parallel-electric-fields-at-play">Parallel electric fields at play</h2>



Gasque's research posits that the emissions from the "picket fence" are generated by low-altitude electric fields parallel to Earth's magnetic field. Employing a widely accepted physical model of the ionosphere, she demonstrated that a parallel electric field of approximately 100 millivolts per meter at an altitude of about 110 km could accelerate electrons. 



This acceleration is sufficient to energize oxygen and nitrogen atoms, resulting in the emission of the <a href="https://svs.gsfc.nasa.gov/12865" target="_blank" rel="noreferrer noopener">spectrum of light</a> observed in the "picket fence" and "Steve" aurora. She also identified unique conditions in this region, such as a reduced plasma density and an increased presence of neutral oxygen and nitrogen atoms. These could serve as an insulator, preventing the electric field from short-circuiting.



"If you look at the spectrum of the picket fence, it's much more green than you would expect. And there's none of the blue that's coming from the ionization of nitrogen," Gasque said. "What that's telling us is that there's only a specific energy range of electrons that can create those colors, and they can't be coming from way out in space down into the atmosphere, because those particles have too much energy."



Instead, she said, "the light from the picket fence is being created by particles that have to be energized right there in space by a parallel electric field, which is a completely different mechanism than any of the aurora that we've studied or known before."



<h2 class="wp-block-heading" id="h-searching-for-steve-with-rockets">Searching for Steve with rockets</h2>



<a href="https://www.ssl.berkeley.edu/full-directory/name/brian-harding/" target="_blank" rel="noreferrer noopener">Brian Harding</a>, an assistant research physicist at SSL and co-author of Gasque's paper, highlights the significance of this discovery. 



"The really interesting thing about Claire's paper is that we've known for a couple of years now that the Steve spectrum is telling us there's some very strange physics going on. We just didn't know what it was," said Brian. "Claire's paper showed that parallel electric fields are capable of explaining this strange spectrum."



The team proposes launching rockets from Alaska to measure electric and <a href="https://www.earth.com/news/solar-wind-collides-magnetic-field/" target="_blank" rel="noreferrer noopener">magnetic fields</a> within these phenomena, aiming to validate their hypotheses. This endeavor aligns with NASA's Low Cost Access to Space (<a href="https://www.science.gov/topicpages/l/low-cost+space+access" target="_blank" rel="noreferrer noopener">LCAS</a>) program and is expected to deepen our comprehension of the upper atmosphere's chemistry and physics. Initially, the target would be what's known as an enhanced aurora, which is a normal aurora with "Steve" and "picket fence"-like emissions embedded in it.



"The enhanced aurora is basically this bright layer that's embedded in the normal aurora. The colors are similar to the picket fence in that there's not as much blue in them, and there's more green from oxygen and red from nitrogen. The hypothesis is that these are also created by parallel electric fields, but they are a lot more common than the picket fence," Gasque said.



The plan is not only "to fly a rocket through that enhanced layer to actually measure those parallel electric fields for the first time," she said, but also send a second rocket up to measure the particles at higher altitudes, "to distinguish the conditions from those that cause the auroras." Eventually, she hopes for a rocket that will fly directly through "Steve and the "picket fence."



<h2 class="wp-block-heading" id="h-curiosity-drives-this-steve-aurora-research">Curiosity drives this "Steve" aurora research</h2>



Gasque credits her success to collaborations with experts studying various atmospheric layers, including the mesosphere and stratosphere. This interdisciplinary approach enabled significant progress in understanding the difference between an aurora and Steve. 



Harding, Gasque, and their colleagues submitted a proposal to NASA for a sounding rocket campaign this fall, anticipating a response about its selection in the first half of 2024. Gasque and Harding view the experiment as a crucial step towards comprehending the chemistry and physics of the upper atmosphere, ionosphere, and <a href="https://www.earth.com/news/geomagnetic-storms-are-influenced-by-earths-atmosphere/" target="_blank" rel="noreferrer noopener">Earth’s magnetosphere</a>. 



"It's fair to say that there's going to be a lot of study in the future about how those electric fields got there, what waves they are or aren't associated with, and what that means for the larger energy transfer between Earth's atmosphere and space," Harding said. "We really don't know. Claire's paper is the first step in the chain of that understanding."



The team eagerly awaits NASA's decision on their proposed rocket campaign, anticipated in the first half of 2024.



In summary, the research led by Claire Gasque marks a pivotal advancement in space physics. Gasque has shed light on the elusive nature of "Steve" and the "picket fence" as being something other than an aurora. As the solar cycle progresses, these findings promise not only to unravel the mysteries of these phenomena but also to enhance our broader understanding of the dynamic interplay between Earth and space.



The full study is published in the journal <a href="https://agupubs.onlinelibrary.wiley.com/doi/10.1029/2023GL106073" target="_blank" rel="noreferrer noopener">Geophysical Research Letters</a>.



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'Steve' phenomenon looks like an aurora, acts like an aurora, but what is it?

The enchanting auroras, with their vibrant displays of green, red,...

A high-speed stream from a coronal hole is expected to lead to G2 (Moderate) geomagnetic storming on December 4 (UTC Day) and G1 (Minor) storming on December 5, 2023, according to an alert this morning from the NOAA Space Weather Prediction Center (<a href="https://www.swpc.noaa.gov/" target="_blank" rel="noreferrer noopener">SWPC</a>).



Coronal holes are striking features of the <a href="https://www.earth.com/news/solar-storms-will-intensify-then-slow-as-the-solar-cycle-peaks-in-early-2024/" target="_blank" rel="noreferrer noopener">Sun</a>, often appearing as dark regions in the solar corona when observed in extreme ultraviolet (EUV) and soft X-ray solar images. These areas are notable for being cooler and less dense compared to the surrounding plasma. The darkness of coronal holes is attributed to their nature as regions of open, unipolar magnetic fields.



<h2 class="wp-block-heading" id="h-role-of-magnetic-fields-in-coronal-holes">Role of magnetic fields in coronal holes</h2>



The open magnetic field line structure of coronal holes is a critical aspect of their behavior. This structure allows the <a href="https://www.earth.com/news/the-solar-wind-which-creates-beautiful-auroras-on-earth-is-now-less-mysterious/" target="_blank" rel="noreferrer noopener">solar wind</a>, a stream of charged particles emitted by the Sun, to escape more easily into space. The result is a stream of relatively fast solar wind, often referred to as a high-speed stream in interplanetary space analysis.



Interestingly, coronal holes can develop at any time and place on the Sun. However, they are more common and persistent around the years of solar minimum. The more persistent coronal holes can last through several solar rotations, each spanning about 27 days.



<h2 class="wp-block-heading" id="h-prevalence-and-stability-of-coronal-holes">Prevalence and stability of coronal holes</h2>



Coronal holes are most prevalent and stable at the solar north and south poles. These polar holes can grow and expand to lower solar latitudes. Additionally, coronal holes can develop in isolation from polar holes, or an extension of a polar hole can split off to become an isolated structure. Persistent coronal holes serve as long-lasting sources for high-speed solar wind streams.



As the high-speed stream interacts with the slower ambient solar wind, a compression region forms, known as a co-rotating interaction region (CIR). From the perspective of a fixed observer in interplanetary space, the CIR will lead the coronal hole high-speed stream (CH HSS).



<h2 class="wp-block-heading" id="h-effects-of-cir-on-planetary-conditions">Effects of CIR on planetary conditions</h2>



The CIR can cause particle density enhancement and interplanetary magnetic field (IMF) strength increases before the onset of the CH HSS. As the CH HSS approaches Earth, solar wind speed and temperature rise, while particle density begins to decrease. After the passage of the CIR and the transition into the CH HSS flow, the overall IMF strength typically starts to weaken.



Coronal holes located near the solar equator are most likely to affect Earth with CIR passage and/or higher solar wind speeds. Strong CIRs and the faster CH HSS can significantly impact Earth’s magnetosphere, causing geomagnetic storms to the G1-G2 levels (Minor to Moderate) on the NOAA Space Weather Scale. 



In rarer cases, stronger storming may occur. The larger and more expansive coronal holes can be a source of high solar wind speeds that affect Earth for extended periods.



<h2 class="wp-block-heading" id="h-forecasting-a-coronal-hole">Forecasting a coronal hole</h2>



Forecasters closely analyze coronal holes for their potential to cause escalated geomagnetic activity and possible storming. They are noted on the daily synoptic drawing. 



The Space Weather Prediction Center (SWPC) forecasters consider the effects of CIR and CH HSS activity when forecasting the anticipated levels of overall planetary geomagnetic response for each 3-hour synoptic period over the next three days, as detailed in the 3-day forecast. Predicted CIR or CH HSS influences are further elaborated in the forecast discussion.



<h2 class="wp-block-heading" id="h-coronal-holes-and-auroras">Coronal holes and auroras</h2>



Coronal holes play a significant role in the creation of <a href="https://www.earth.com/news/aurora-borealis-seen-as-far-south-as-the-equator-after-largest-known-solar-storm/" target="_blank" rel="noreferrer noopener">auroras</a> on Earth. These dark areas on the Sun's surface, characterized by open magnetic fields, allow solar winds to escape more easily into space. When these high-speed solar winds, often emanating from coronal holes, reach Earth, they can interact with the planet's magnetosphere. This interaction involves the solar wind's charged particles colliding with Earth's magnetic field and atmosphere.



As the solar wind penetrates the magnetosphere, it can cause <a href="https://www.earth.com/news/noaa-alert-strong-geomagnetic-storm-warning-issued-due-to-strong-solar-flare/" target="_blank" rel="noreferrer noopener">geomagnetic storms</a>, especially if the incoming solar wind is strong and fast. These storms disturb the magnetosphere and lead to the acceleration of electrons and protons. When these accelerated particles collide with gases in Earth's upper atmosphere, such as oxygen and nitrogen, they excite these gases, causing them to release photons - the basic units of light. This release of photons results in the shimmering lights known as auroras.



The intensity and frequency of auroras often depend on the strength of the solar wind and the geomagnetic storms it induces. Coronal holes, being significant sources of fast solar winds, can enhance the likelihood and intensity of auroras. During times when Earth encounters streams of solar wind from these coronal holes, the chances of observing auroras at higher and sometimes lower latitudes increase. This phenomenon makes coronal holes an essential factor in predicting and understanding auroral activities on Earth.



In summary, understanding coronal holes and their associated phenomena is crucial for anticipating and mitigating the impacts of solar activity on Earth’s magnetosphere and space weather conditions.



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Massive "coronal hole" in the Sun prompts aurora alert for southern states

A high-speed stream from a coronal hole is expected to...

Vegan,Burger,With,White,Bean,Puree,And,Spicy,Aubergine,Slices

A recent UN Environment Programme (UNEP) assessment presents a compelling case for novel alternatives to meat and dairy products as a means to significantly reduce the environmental footprint of the <a href="https://www.earth.com/news/global-food-system-must-change-if-nations-hope-to-reduce-greenhouse-gas-emissions/" target="_blank" rel="noreferrer noopener">global food system</a>. This is especially pertinent in high- and middle-income countries, where the reliance on low-carbon energy is crucial. 



The report, titled "<a href="https://www.unep.org/resources/whats-cooking-assessment-potential-impacts-selected-novel-alternatives-conventional" target="_blank" rel="noreferrer noopener">What’s cooking? An assessment of the potential impact of select novel alternatives to conventional animal products</a>", highlights three main types of alternatives: novel plant-based meats, cultivated meat from animal cells, and protein-rich products derived through rapid fermentation by microorganisms.



<h2 class="wp-block-heading" id="h-environmental-and-health-benefits">Environmental and health benefits</h2>



The UNEP report, supported by the Government of Belgium, underscores the substantial potential of these alternatives in reducing greenhouse gas (GHG) emissions. Additionally, they can aid in mitigating land degradation, deforestation, water and soil pollution, and biodiversity loss. 



These alternatives also present a lower risk of zoonotic diseases and anti-microbial resistance, and they address animal welfare concerns more effectively compared to traditional animal products.



The authors of the report posit that these novel alternatives can contribute to a more sustainable, healthier, and <a href="https://www.earth.com/news/cowspiracy-film-review/" target="_blank" rel="noreferrer noopener">humane food system</a>. However, they emphasize that regional differences will play a significant role in their implementation. 



The report reviews various policy decisions that could <a href="https://www.earth.com/news/reducing-food-waste-greater-food-security-less-environmental-benefits/" target="_blank" rel="noreferrer noopener">enhance food security</a>, jobs, livelihoods, social and gender equity, and cultural aspects, thus maximizing the benefits of these novel meat and dairy alternatives.



<h2 class="wp-block-heading" id="h-animal-products-vs-meat-alternatives">Animal products vs. meat alternatives</h2>



Inger Andersen, the Executive Director of <a href="http://www.unep.org/" target="_blank" rel="noreferrer noopener">UNEP</a>, highlighted the importance of new food alternatives in providing a broader spectrum of consumer choices. 



“New food alternatives will offer a broader spectrum of consumer choices,” said Andersen. “Further, such <a href="https://www.earth.com/earthpedia-articles/is-a-plant-based-diet-healthy/" target="_blank" rel="noreferrer noopener">alternatives</a> can also lessen the pressures on agricultural lands and reduce emissions, thereby helping us address the triple planetary crisis - the crisis of climate change, the crisis of biodiversity and nature loss, the crisis of pollution and waste - as well as address the health and environmental consequences of the animal agriculture industry. More government support, as well as open and transparent research, can help unlock the potential of these new technologies for some countries.”



The report sheds light on the negative impacts of conventional animal product production and consumption, especially in high- and middle-income countries. These include environmental degradation and <a href="https://www.earth.com/news/vegan-diet-improves-heart-health-in-a-matter-of-weeks/" target="_blank" rel="noreferrer noopener">public health concerns</a> such as cardiovascular diseases, certain cancers, obesity, and diabetes. The animal agriculture industry also poses risks of anti-microbial resistance and zoonotic diseases like <a href="https://www.earth.com/news/plant-based-diets-reduce-the-risk-of-severe-covid-19/" target="_blank" rel="noreferrer noopener">COVID-19</a> or Avian Influenza.



<h2 class="wp-block-heading" id="h-climate-change-and-animal-agriculture">Climate change and animal agriculture</h2>



<a href="https://www.earth.com/news/cattle-farming-expansion-could-expose-more-than-a-billion-cows-to-heat-stress/" target="_blank" rel="noreferrer noopener">Animal agriculture</a> is a significant contributor to climate change, accounting for nearly 60% of food-related GHG emissions and 14-20% of global GHG emissions. This includes emissions from animal GHG, feed production, land use changes, and energy-intensive supply chains.



While these <a href="https://www.earth.com/news/plant-based-diets-are-proven-better-for-human-and-environmental-health/" target="_blank" rel="noreferrer noopener">novel alternatives</a> offer benefits in terms of animal welfare and public health improvements, some concerns remain. For instance, many novel plant-based products are highly processed and may contain high levels of salt and saturated fats. The health impacts of cultured meat and fermentation-derived products are still under investigation.



<h2 class="wp-block-heading" id="h-social-and-cultural-acceptability">Social and cultural acceptability</h2>



The report acknowledges that the success of novel alternatives depends on factors like cost, taste, and social and cultural acceptability. These factors will significantly influence consumer behavior, especially in high- and middle-income countries where animal protein consumption is unsustainably high.



The UNEP report suggests several policy options to guide the food industry towards a healthier and more sustainable future. These include supporting open access research, shifting subsidies, tax rebates, direct financial investments, and loan guarantees favoring <a href="https://www.earth.com/news/increasing-plant-based-food-production-would-have-extremely-positive-impact/" target="_blank" rel="noreferrer noopener">novel alternatives</a> to meat. The report also emphasizes the need for equitable and regionally appropriate approaches to food system changes.



<h2 class="wp-block-heading" id="h-socio-economic-implications-of-meat-alternatives">Socio-economic implications of meat alternatives</h2>



The authors call for open and transparent research to understand the nutritional and socio-economic implications of these alternatives. This includes considering their impact on equity, food security, and the livelihoods of smallholder farmers.



The report does not address meat from wild animals, fish, or other aquatic animals, nor does it assess other food system alternatives like regenerative livestock farms, feed additives, insect farming, reduced meat consumption, or taxing meat. While these alternatives are being pursued, they have yet to achieve significant government support or impact at the desired scale or speed.



In summary, the UNEP report presents a comprehensive analysis of <a href="https://www.earth.com/news/plant-based-foods-are-great-for-weight-loss-regardless-of-the-type/" target="_blank" rel="noreferrer noopener">novel alternatives</a> to meat and dairy products, highlighting their potential benefits and challenges. It offers a roadmap for policymakers, industry stakeholders, and consumers to navigate the transition towards a more sustainable and humane food system.



 This study is a part of <a href="https://www.unep.org/resources/frontiers" target="_blank" rel="noreferrer noopener">UNEP’s Frontiers series</a>, which focuses on emerging environmental concerns.



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New meat and dairy alternatives will dramatically transform the global food system

A recent UN Environment Programme (UNEP) assessment presents a compelling...

The moon has entered into a new phase of existence due to human influence. In a new study from the <a href="https://ku.edu/" target="_blank" rel="noreferrer noopener">University of Kansas</a>, experts say that it is time to recognize a new epoch on the <a href="https://www.earth.com/news/nasa-plans-to-build-house-on-the-moon-by-2040/">moon</a>: the Lunar Anthropocene.



This proposal is rooted in the first human-induced disturbance on the moon on September 13, 1959, when the USSR's Luna 2 mission made contact with the lunar surface.&nbsp;



Since then, the moon has been host to over 100 spacecraft, including the famed Apollo Lunar Modules. These visits have left indelible marks on the moon, altering its landscape in ways previously unimagined.



<h2 class="wp-block-heading" id="h-lunar-anthropocene-nbsp">Lunar Anthropocene&nbsp;</h2>



“The idea is much the same as the discussion of the Anthropocene on Earth - the exploration of how much humans have impacted our planet,” said study lead author Justin Holcomb, a postdoctoral researcher with the <a href="https://kgs.ku.edu/" target="_blank" rel="noreferrer noopener">Kansas Geological Survey</a> at KU.&nbsp;



“The consensus is on Earth the Anthropocene began at some point in the past, whether hundreds of thousands of years ago or in the 1950s. Similarly, on the moon, we argue the Lunar Anthropocene already has commenced, but we want to prevent massive damage or a delay of its recognition until we can measure a significant lunar halo caused by human activities, which would be too late."



<h2 class="wp-block-heading" id="h-no-longer-an-untouched-entity-nbsp">No longer an untouched entity&nbsp;</h2>



Collaborating with Professor Rolfe Mandel and Professor Karl Wegmann at North Carolina State University, Holcomb emphasizes that the lunar landscape is no longer a static, untouched entity.&nbsp;



“Cultural processes are starting to outstrip the natural background of geological processes on the moon,” said Holcomb. “These processes involve moving sediments, which we refer to as ‘regolith,’ on the moon."



<h2 class="wp-block-heading" id="h-initiating-discussions-nbsp">Initiating discussions&nbsp;</h2>



"Typically, these processes include meteoroid impacts and mass movement events, among others. However, when we consider the impact of rovers, landers and human movement, they significantly disturb the regolith. In the context of the new space race, the lunar landscape will be entirely different in 50 years."&nbsp;



"Multiple countries will be present, leading to numerous challenges. Our goal is to dispel the lunar-static myth and emphasize the importance of our impact, not only in the past but ongoing and in the future. We aim to initiate discussions about our impact on the lunar surface before it's too late.”



<h2 class="wp-block-heading" id="h-delicate-exosphere-nbsp">Delicate exosphere&nbsp;</h2>



“We know that while the Moon does not have an atmosphere or magnetosphere, it does have a delicate exosphere composed of dust and gas, as well as ice inside permanently shadowed areas, and both are susceptible to exhaust gas propagation,” wrote the study authors. “Future missions must consider mitigating deleterious effects on lunar environments.”



While Holcomb and his colleagues want to use the Lunar Anthropocene to highlight the potential for humanity’s potential negative environmental impact to the moon, they also hope to call attention to the vulnerability of lunar sites with historical and anthropological value, which currently have no legal or policy protections against disturbance.



<h2 class="wp-block-heading" id="h-historical-artifacts-nbsp">Historical artifacts&nbsp;</h2>



The team's concern extends to the remnants of human missions on the moon, ranging from scientific equipment to more unconventional items like golf balls and religious texts. These artifacts, they argue, are not merely litter but constitute a unique archaeological record of human presence in space.&nbsp;



“A recurring theme in our work is the significance of lunar material and footprints on the moon as valuable resources, akin to an archaeological record that we’re committed to preserving,” said Holcomb.&nbsp;



“The concept of a Lunar Anthropocene aims to raise awareness and contemplation regarding our impact on the lunar surface, as well as our influence on the preservation of historical artifacts.”



<h2 class="wp-block-heading" id="h-space-heritage-nbsp">Space heritage&nbsp;</h2>



Holcomb said this field of “space heritage” would aim to preserve or catalog items such as rovers, flags, golf balls and footprints on the moon’s surface.



“As archaeologists, we perceive footprints on the moon as an extension of humanity's journey out of Africa, a pivotal milestone in our species' existence."



“These imprints are intertwined with the overarching narrative of evolution. It’s within this framework we seek to capture the interest of not only planetary scientists but also archaeologists and anthropologists who may not typically engage in discussions about planetary science.”



The study is published in the journal <a href="http://dx.doi.org/10.1038/s41561-023-01347-4" target="_blank" rel="noreferrer noopener">Nature Geoscience</a>.



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Lunar Anthropocene: How humans have impacted the moon

The moon has entered into a new phase of existence...

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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

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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



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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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