For decades, scientists have been grappling with what is considered to be the most fundamental question about the cosmos: How fast is our universe expanding? 



The rate of expansion influences everything from how galaxies form to how they might one day drift apart.



Determining the expansion rate of the universe, a number called the "Hubble constant," shapes our entire understanding of the cosmos, its age, and its ultimate fate.



<h2 class="wp-block-heading" id="h-hubble-tension-expansion-conundrum">"Hubble tension" expansion conundrum</h2>



Unfortunately, though many brilliant minds have dedicated their lives to finding the answer to this riddle, all who have tried thus far have failed, running repeatedly into a brick wall that has come to be known as the "Hubble tension."



Adam Riess, a physicist at <a href="https://www.jhu.edu/" target="_blank" rel="noreferrer noopener">Johns Hopkins University</a> in Baltimore, has been at the forefront of this debate. "With measurement errors negated, what remains is the real and exciting possibility that we have misunderstood the universe," Riess admitted.



Riess, who won a Nobel Prize for discovering that the universe's expansion is accelerating due to dark energy, has been working tirelessly to resolve what's known as the Hubble Tension.



<h2 class="wp-block-heading" id="h-why-the-hubble-constant-matters">Why the Hubble constant matters</h2>



But before diving deeper, let's consider why the expansion rate -- called the Hubble constant -- is so crucial. 



Named after Edwin Hubble, who first observed that galaxies are moving away from us, this constant helps us map out the history and future of everything we see in the night sky. 



Determining it with precision has been a major goal of astronomers for decades.



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/11/hubble-constant_3-steps_illustration_nasa_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/11/hubble-constant_3-steps_illustration_nasa_1s.webp" alt="This illustration shows the three basic steps astronomers use to calculate how fast the universe expands over time, a value called the Hubble constant. All the steps involve building a strong &quot;cosmic distance ladder,&quot; by starting with measuring accurate distances to nearby galaxies and then moving to galaxies farther and farther away. Credit: NASA" class="wp-image-1951709"/></a><figcaption class="wp-element-caption">This illustration shows the three basic steps astronomers use to calculate how fast the universe expands over time, a value called the Hubble constant. All the steps involve building a strong "cosmic distance ladder," by starting with measuring accurate distances to nearby galaxies and then moving to galaxies farther and farther away. Credit: NASA</figcaption></figure>



When the <a href="https://hubblesite.org/home" target="_blank" rel="noreferrer noopener">Hubble Space Telescope</a> was launched in 1990, one of its main objectives was to pin down the universe's expansion rate. 



Before Hubble, estimates of the universe's age ranged wildly from 10 to 20 billion years -- a huge uncertainty. 



Thanks to Hubble's observations of <a href="https://www.earth.com/news/expansion-rate-of-the-universe-confirmed-by-jwst/" target="_blank" rel="noreferrer noopener">Cepheid variable stars</a> -- stars that pulsate at regular intervals and serve as cosmic mileposts -- we now have a more precise age of about 13.8 billion years.



<h2 class="wp-block-heading" id="h-webb-telescope-to-the-rescue">Webb telescope to the rescue?</h2>



Some scientists wondered if the discrepancies in measurements were due to errors in Hubble's data. Maybe, they thought, the way Hubble measured distances had some hidden flaws. 



Then came the James Webb Space Telescope (<a href="https://science.nasa.gov/mission/webb/" target="_blank" rel="noreferrer noopener">Webb</a>), launched to great fanfare as the successor to Hubble. Webb's infrared observations of Cepheids matched Hubble's optical data perfectly. 



"Combining Webb and Hubble gives us the best of both worlds. We find that the Hubble measurements remain reliable as we climb farther along the cosmic distance ladder," Riess explained.



<h2 class="wp-block-heading" id="h-hubble-vs-webb-vs-expansion">Hubble vs. Webb vs. expansion</h2>



Despite the new data, the tension between measurements remains. The Hubble and Webb telescopes confirm one universe expansion rate, based on observations of the local universe.



Meanwhile, observations from the early universe, like those from the Planck satellite's mapping of the cosmic microwave background radiation, suggest another. 



This leaves cosmologists scratching their heads. Is there something about the <a href="https://www.earth.com/news/universe-expansion-rate-dark-energy-measured-11-billion-years-ago/" target="_blank" rel="noreferrer noopener">fabric of space</a> we don't yet understand? Does resolving this discrepancy require new physics, or is there another explanation?



<h2 class="wp-block-heading" id="h-brenda-frye-tackles-hubble-and-expansion">Brenda Frye tackles Hubble and expansion</h2>



In October 2024, <a href="https://blogs.nasa.gov/webb/2024/10/01/webb-researchers-discover-lensed-supernova-confirm-hubble-tension/" target="_blank" rel="noreferrer noopener">as reported by NASA</a>, Brenda Frye from the <a href="https://www.arizona.edu/" target="_blank" rel="noreferrer noopener">University of Arizona</a> and an international team took a different approach. 



They used <a href="https://www.earth.com/news/webb-telescope-finds-a-second-lensed-supernova-in-a-distant-galaxy/" target="_blank" rel="noreferrer noopener">gravitationally lensed supernovae</a> to measure the Hubble constant -- a method independent of previous techniques. 



<figure class="wp-block-image aligncenter size-full"><a href="https://www.earth.com/wp-content/uploads/2024/11/hubble-constant_galaxy-cluster-G165_supernova-H0pe_gravitational-lensing_jwst_UArizona_1m.jpg" target="_blank" rel="noreferrer noopener"><img src="https://www.earth.com/wp-content/uploads/2024/11/hubble-constant_galaxy-cluster-G165_supernova-H0pe_gravitational-lensing_jwst_UArizona_1s.webp" alt="NASA’s James Webb Space Telescope’s NIRCam (Near-Infrared Camera) image of the galaxy cluster PLCK G165.7+67.0, also known as G165, on the left shows the magnifying effect a foreground cluster can have on the distant universe beyond. The foreground cluster is 3.6 billion light-years away from Earth. The zoomed region on the right shows supernova H0pe triply imaged (labeled with white dashed circles) due to gravitational lensing. Credit: NASA, ESA, CSA, STScI, B. Frye (University of Arizona)" class="wp-image-1951711"/></a><figcaption class="wp-element-caption">NASA’s James Webb Space Telescope’s NIRCam (Near-Infrared Camera) image of the galaxy cluster PLCK G165.7+67.0, also known as G165, on the left shows the magnifying effect a foreground cluster can have on the distant universe beyond. The foreground cluster is 3.6 billion light-years away from Earth. The zoomed region on the right shows supernova H0pe triply imaged (labeled with white dashed circles) due to gravitational lensing. Credit: NASA, ESA, CSA, STScI, B. Frye (University of Arizona)</figcaption></figure>



While observing a densely populated cluster of galaxies, they noticed something unusual. "What are those three dots that weren’t there before? Could that be a supernova?" the team wondered. 



It turned out to be a <a href="https://www.earth.com/news/webb-travels-back-in-time-to-better-understand-supernovae-science/" target="_blank" rel="noreferrer noopener">Type Ia supernova</a>, an explosion of a <a href="https://www.earth.com/news/white-dwarf-stars-may-be-billions-of-years-older-than-estimated/" target="_blank" rel="noreferrer noopener">white dwarf star</a>, magnified and split into multiple images by the gravitational lensing effect of the intervening galaxy cluster.



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



<a href="https://www.earth.com/news/rare-carousel-lens-galaxy-alignment-reveals-dark-matter-secrets/" target="_blank" rel="noreferrer noopener">Gravitational lensing</a> is important to this experiment. The lens, consisting of a cluster of galaxies situated between the supernova and us, bends the supernova's light into multiple images. 



This effect not only magnifies the supernova but also allows scientists to measure the time delays between the images, providing another way to calculate the Hubble constant.



Their analyses confirmed that these dots corresponded to an exploding star with rare qualities. 



The team's work provided a Hubble constant value of 75.4 kilometers per second per megaparsec, plus 8.1 or minus 5.5. For context, one megaparsec is about 3.26 million light-years. 



"Our team’s results are impactful: The Hubble constant value matches other measurements in the local universe, and is somewhat in tension with values obtained when the universe was young," Frye concluded.



Another strikeout... add Brenda Frye to the long list of brilliant minds still probing the universe for an answer to Hubble tension.



<h2 class="wp-block-heading" id="h-this-is-getting-sad-now-what">This is getting sad, now what?</h2>



So, where does this leave us? 



The Hubble Tension isn't going away. It might be telling us that there's new physics waiting to be discovered. 



Perhaps our understanding of <a href="https://www.earth.com/news/dark-energy-could-explain-the-rapid-expansion-of-the-early-universe/" target="_blank" rel="noreferrer noopener">dark energy</a>, dark matter, or other fundamental forces needs to be revised. 



"We need to find out if we are missing something on how to connect the beginning of the universe and the present day," Riess pointed out. 



It's possible that new theories or modifications to existing ones could bridge the gap.



<h2 class="wp-block-heading" id="h-shaking-things-up-with-new-theories">Shaking things up with new theories</h2>



Could the solution lie in something entirely unexpected? Perhaps there's a <a href="https://www.earth.com/news/dark-matter-may-consist-of-particles-that-travel-faster-than-light/" target="_blank" rel="noreferrer noopener">new particle or force</a> that affects the expansion rate. Or maybe the nature of dark energy changes over time. 



Some theories even propose the existence of extra dimensions or modifications to gravity at large scales. It's also worth considering that the universe might not be uniform in all directions. 



If there are variations in the density of matter and energy across vast distances, this could affect expansion rates in ways we haven't fully accounted for. 



Maybe everyone is completely off base and <a href="https://www.earth.com/news/study-dark-matter-does-not-exist-and-the-universe-is-27-billion-years-old/" target="_blank" rel="noreferrer noopener">dark matter doesn't even exist</a>? Or maybe we're looking in the wrong place -- what if the answers can be found by looking for <a href="https://www.earth.com/news/scientists-are-now-searching-for-dark-matter-inside-old-earth-rocks-minerals-crystals/" target="_blank" rel="noreferrer noopener">dark matter in rocks on Earth</a>?



One thing's for sure: the cosmos isn't giving up its secrets easily. But that's part of the thrill of science. Every answer leads to new questions.



<h2 class="wp-block-heading" id="h-hubble-constant-hubble-tension-mysterious-universe">Hubble constant, Hubble tension, mysterious universe</h2>



In the end, the universe is reminding us that there's still so much we don't know. The quest to figure out how fast our universe is expanding has led to some fascinating discoveries and even more intriguing questions. 



Scientists like Adam Riess and Brenda Frye have used powerful tools like the Hubble and James Webb Space Telescopes to measure the Hubble constant with increasing precision. 



Their efforts confirm that the local universe is expanding at a certain rate, but this doesn't quite line up with measurements from the early universe.



This mismatch, known as the Hubble Tension, suggests there might be something we’re missing in our understanding of the cosmos. Maybe there are new physics to uncover, or perhaps our current models need some tweaking. 



What's clear is that the universe isn't giving up its secrets easily, and that keeps things exciting for astronomers and physicists alike.



As we look ahead, upcoming missions like NASA's <a href="https://roman.gsfc.nasa.gov/" target="_blank" rel="noreferrer noopener">Nancy Grace Roman Space Telescope</a> and ESA's <a href="https://www.esa.int/Science_Exploration/Space_Science/Euclid" target="_blank" rel="noreferrer noopener">Euclid mission</a> offer hope for new insights. Until then, we can marvel at the fact that we're part of an ever-expanding universe that's still full of surprises.



The full study was published in the <a href="https://iopscience.iop.org/article/10.3847/2041-8213/ad1ddd" target="_blank" rel="noreferrer noopener">Astrophysical Journal Letters</a>.



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Webb telescope confirms: What we think we know about the universe is very wrong

For decades, scientists have been grappling with what is considered to be the most fundamental question about the cosmos: How fast is our universe expanding? The rate of expansion influences everything from how galaxies form to how they might one day drift apart. Determining the expansion rate of the universe, a number called the "Hubble constant," shapes our entire understanding of the cosmos, its age, and its ultimate fate. "Hubble tension" expansion conundrum Unfortunately, though many brilliant minds have dedicated their lives to finding the answer to...

A new study from the <a href="https://www.sdu.dk/en">University of Southern Denmark</a> has revealed that songbirds have extremely high-resolution control over their vocal output. The experts report that birds can control single vocal muscle fibers while singing.

Songbirds have a unique vocal organ they use to produce their beautiful songs. This organ is surrounded by muscles that contract at high speeds.

"We found that songbirds have incredible fine control of their song, including frequency control below one Hertz," said study lead author Professor Iris Adam.

A motor unit refers to a motor neuron and all of the muscle fibers that it activates. The researchers found that a large portion of the motor units must be very small - even as small as single muscle fiber.

"Motor units vary in size from several hundreds or thousands of muscle fibers in our leg muscles down to only 5-10 in the muscles controlling eye position and the muscles in the larynx," explained study senior author Dr. Coen Elemans.

"In zebra finch song muscles our models predicted that 13-17% of the motor neurons innervates a single muscle fiber."

The team developed a new technique to measure the activity of all muscle fibers within a small muscle.

"Our new method allowed us for the first time to activate single motor neurons and visualize and record the activity of all responding muscle fibers simultaneously," said Professor Adam.

"Like this we were able to show that the song muscles of zebra finches indeed contain motor units as small as one muscle fiber."

The researchers wanted to know what effect such small motor units may have on birdsong. They measured the amount of stress the muscles can make and how such stress changes the frequency of the sound.

"Next to small motor units, we discovered that songbird vocal muscles have the lowest stress measured in any vertebrate," said Professor Adam.

"To be able to study how changes in muscle force alter the sound made by the birds' vocal organ, the syrinx, we had to invent a new setup," said Dr. Elemans. "This setup blows air through the syrinx while we can control the muscles with small motors."

Professor Adam noted that songbird vocal muscles are among the fastest muscles known, and now we show that they are also the weakest with the highest level of control possible.

It is important for the songbirds to maintain this level of control. Previous research has shown that females can detect small changes that influence whether they are attracted to a male or not.

"We think that next to a special syrinx and their amazing ability to imitate sounds, the fine gradation of the song features such as pitch has increased the amount of different sounds a bird can make," said Professor Adam.

The study is published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Songbirds can control single muscle fibers while singing

A new study from the University of Southern Denmark has...

In a new study published by <a href="https://www.cell.com/">Cell Press</a>, experts have discovered that North <a href="https://www.earth.com/news/predatory-lionfish-have-arrived-in-the-south-atlantic/">Atlantic</a> right whales have become significantly shorter in the last three to four decades. The experts report that, since the 1980s, the average length of the whales has declined by about seven percent.

The research suggests that even though whales are now largely protected from direct catch, other stressors are having an impact on their fitness. 

"On average, a whale born today is expected to reach a total length about a meter shorter than a whale born in 1980," explained <a href="https://www.noaa.gov/">NOAA</a> scientist Joshua Stewart. "But that's just the average - there are also some extreme cases where young whales are several meters shorter than expected."

"Major impacts on life history like this have been documented in heavily exploited commercial species, especially fishes, but to our knowledge this is the first time these kinds of impacts are being recorded in a large mammal."

In collaboration with an international team of scientists, Stewart set out to document the challenges faced by right whales as indicated by changes in their life history characteristics, including size. The experts analyzed aerial photogrammetry measurements collected over 20 years.

"We were able to build on our previous work that used conventional aircraft in the early 2000s by adopting new drone technology to extend the time series in recent years," said John Durban at Oregon State University (formerly with NOAA). "In both cases, we were able to measure whales by flying a camera high above them, essentially giving them a health check without them knowing we were there."

The whales have been consistently monitored since the 1980s, including detailed records of attached-gear entanglements, age, and size. Beyond the effects of entanglements, the experts examined the potential impacts of other stressors such as noise, ship strikes, and prey availability.

"Fishing gear entanglements in this population are unfortunately fairly common, and entanglements resulting in attached gear and severe injuries have been generally increasing over the past several decades," Stewart said. 

"Previous studies have shown that the increased drag from entangling gear requires right whales to spend a lot of extra energy just to go about their normal activities, and that is energy they might otherwise spend on growth or reproduction. In some cases, entanglements can be lethal, but it turns out that even sub-lethal entanglements can have lasting impacts on right whales."

The findings show that entanglements are one of the stressors associated with shorter whales. According to the researchers, stunted growth in right whales may lead to a higher risk of life-threatening gear entanglements, as well as reduced reproductive success.

"The smaller you are, the less energetic reserves you have, and the harder it might be to survive a serious entanglement or sustained food shortage," explained Stewart. 

"So it's possible that these life history changes could translate into population viability impacts. But this really makes me wonder about how large whales worldwide are being impacted by entanglements. This is by no means a problem unique to right whales - entanglements are a major threat for whales, marine mammals, and other marine species worldwide."

"Because North Atlantic right whales have this incredibly detailed dataset with known ages, sizes, entanglement histories, and so forth, we could directly examine how these impacts are affecting growth rates. My guess is that many other species are being similarly affected, but we just don't have the ability to detect it in less well-studied populations."

The study is published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

North Atlantic right whales are getting shorter

In a new study published by Cell Press, experts have...

A recent study led by <a href="https://www.ucl.ac.uk/">University College London</a> suggests that sea ice in coastal regions of the <a href="https://www.earth.com/news/arctic-warming-is-not-properly-represented-in-climate-targets/">Arctic</a> is thinning at up to double the rate that was expected. 

The researchers used a new computer model designed to estimate snow depth as it varies year to year. The results showed that coastal Arctic sea ice is thinning 70 to 100 percent faster than previously thought.

"The thickness of sea ice is a sensitive indicator of the health of the Arctic," said study lead author Robbie Mallett. "It is important as thicker ice acts as an insulating blanket, stopping the ocean from warming up the atmosphere in winter, and protecting the ocean from the sunshine in summer. Thinner ice is also less likely to survive during the Arctic summer melt."

"Previous calculations of sea ice thickness are based on a snow map last updated 20 years ago. Because sea ice has begun forming later and later in the year, the snow on top has less time to accumulate. Our calculations account for this declining snow depth for the first time, and suggest the sea ice is thinning faster than we thought."

According to study co-author Professor Julienne Stroeve, there are a number of uncertainties in measuring sea ice thickness, but the researchers believe their new calculations represent a major step forward in terms of more accurately interpreting satellite data.

"We hope this work can be used to better assess the performance of climate models that forecast the effects of long-term climate change in the Arctic - a region that is warming at three times the global rate, and whose millions of square kilometres of ice are essential for keeping the planet cool."

The experts used radar from the European Space Agency's CryoSat-2 satellite to calculate sea ice thickness. They combined the data with a new computer model that calculates snow depth and density using inputs such as air temperature, snowfall, and ice motion. 

Based on this information, the team estimated the overall rate thinning sea ice in the Arctic, as well as the variability of sea ice thickness from year to year.

When compared to earlier calculations, the rate of decline had increased across the three coastal seas of Laptev, Kara and Chukchi seas by 70, 98, and 110 percent respectively. Furthermore, across all seven coastal seas, the variability in sea ice thickness from year to year increased by 58 percent.

The rapid thinning of sea ice in the coastal Arctic seas has implications for human activity in the region, both in terms of shipping along the Northern Sea Route for a larger part of the year, as well as the extraction of resources from the sea floor such as oil, gas and minerals.

"More ships following the route around Siberia would reduce the fuel and carbon emissions necessary to move goods around the world, particularly between China and Europe. However, it also raises the risk of fuel spillages in the Arctic, the consequences of which could be dire," said Mallett. 

"The thinning of coastal sea ice is also worrying for indigenous communities, as it leaves settlements on the coast increasingly exposed to strong weather and wave action from the emerging ocean."

The study is published in the journal <a href="https://www.the-cryosphere.net/">Cryosphere</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Coastal sea ice is thinning faster than expected in the Arctic

A recent study led by University College London suggests that...

In a new study published by <a href="https://plos.org/">PLOS</a>, geophysicist Dr. Gidon Eshel has demonstrated that mixed farming methods could reduce greenhouse gas emissions and increase <a href="https://www.earth.com/news/food-waste-can-be-recycled-into-construction-materials/">food</a> productivity in the United States. 

Dr. Eshel reports that mixed farming, which also avoids synthetic fertilizers in favor of manure, could be established across the country's 100 million hectares of high quality cropland to help eliminate greenhouse gas emissions. In this scenario, beef consumption would need to decrease, but by only 20 percent. 

Beef is the most costly food item in terms of resources. For every gram of protein, beef uses seven times more cropland and 20 times more water. Beef production is also responsible for 11 times higher greenhouse gas emissions compared to other protein sources. 

On the other hand, cattle manure is a valuable source of natural fertilizer. Relying on cattle manure and nitrogen-fixing crops to replenish soil nutrients helps to eliminate harmful synthetic fertilizers.

To investigate whether these practices could support farming in the United States, Dr. Eshel created a mathematical model of nitrogen-sparing agriculture across all high quality cropland in the country, totaling 100 million hectares. He divided this area into identical mixed-use farm units that integrated intensive cattle farming with production of fruit, vegetables, grains, nuts, and cattle forage.

&nbsp;

The modeling study revealed that mixed farming practices could cut out 55 percent of current nitrogen fertilizer use while also eliminating agricultural greenhouse gas emissions. Nitrogen-sparing practices also increased productivity and total protein production - the modeled farms yielded 110 percent of current consumption and produced a more protein-rich diet. Meanwhile, mixed farming reduced beef production by 20 to 30 percent.

Nitrogen-sparing practices could help reduce agricultural greenhouse gas emissions and minimize harmful fertilizer run-off, but their success will depend on complex societal, economic, and political factors, said Dr. Eshel.

"While small-scale regenerative farming has been promoted for many years, nobody quite knew whether it can feed the populace. Without taking sides in this raging debate, I set out to agnostically test whether such practices can or cannot produce enough food."

"I developed a mathematical model of such farms dotting the contiguous U.S. landscape, but only where precipitation is bountiful and the soil of high quality, and found that such farms can in fact handily feed the U.S., including delivering four fifths of today's beef consumption and quite dramatically improve nutrition and by extension public health."

The study is published in the journal <a href="https://journals.plos.org/plosbiology/">PLOS Biology</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Mixed farming could increase food productivity and reduce emissions

In a new study published by PLOS, geophysicist Dr. Gidon...

A new study has confirmed that lionfish have invaded the South Atlantic Ocean off the coast of Brazil. An international team of experts led by the <a href="https://www.calacademy.org/">California Academy of Sciences</a> warns that management of the predatory fish is critical to protecting Brazil's coral reefs and marine biodiversity. 

According to <a href="https://www.fisheries.noaa.gov/southeast/ecosystems/impacts-invasive-lionfish">NOAA</a>, a single lionfish residing on a coral reef can reduce recruitment of native reef fish by 79 percent. "Lionfish feed on prey normally consumed by snappers, groupers, and other commercially important native species. This means their presence could negatively affect the well-being of valuable commercial and recreational fisheries," reports NOAA.

Less than 30 years after arriving in the northern Atlantic Ocean, lionfish have expanded at astonishing speeds to become one of the most widespread and destructive invasive species. They have negatively impacted coral reefs and other marine ecosystems from the northeast coast of the United States to the Caribbean Islands. 

"For a while it was uncertain whether or not lionfish would extend into the South Atlantic," said study co-author Luiz Rocha. "Now that we know they are here, it is imperative that we uncover how they arrived and work with local communities to keep the population under control." 

"If left unchecked, lionfish could have a huge impact on local species, particularly those that exist solely in the reefs surrounding Brazil's oceanic islands."

Lionfish have maroon stripes and more than a dozen venomous spines. They are native to the tropical waters of the South Pacific and Indian Oceans, but are very popular in the aquarium trade. It is likely that aquarium releases are responsible for the lionfish invasion in the Atlantic Ocean. 

Lionfish have expanded faster than any other invasive marine species. The researchers explain that the capacity to spread is due to their broad diet, lack of natural predators, unique hunting style, and year-round reproduction of eggs that can travel long distances on ocean currents.

Up until 2015, when a local diver photographed a lionfish swimming off the southern coast of Brazil, the predators remained noticeably absent in the South Atlantic. 

After the researchers were alerted to the sighting, they enlisted the help of local fishermen and divers to track down the initial specimen along with three additional lionfish in Brazil's waters.

"The arrival of lionfish to Brazil's oceanic islands is especially worrying," said study co-author Clara Buck. "These unique ecosystems have a high number of endemic species found nowhere else on Earth making them much more sensitive to adverse impacts."

To stop the invasion before it ramps up, scientists must determine how the lionfish are arriving in the region in the first place. Regardless of how they arrived, however, the researchers are urging the Brazilian government and local communities to stem the invasion. 

The experts say that keeping population numbers low could buy precious time for species to adapt to the voracious fish and ultimately avoid predation. Local fishermen and divers, such as those who assisted with this study, will play a critical role in managing the invasion.

"Brazil, and Fernando de Noronha in particular, have robust local diving and fishing communities," said Rocha. "If we put the right tools in their hands, it is absolutely possible to keep the invasion under control."

The study is published in the journal <a href="https://www.springer.com/journal/10530">Biological Invasions</a>.

---

By <a href="http://csexton@earth.com">Chrissy Sexton</a>, <a href="https://www.earth.com/staff/">Earth.com</a> Staff Writer

Predatory lionfish have arrived in the South Atlantic

A new study has confirmed that lionfish have invaded the...

Puppies have the capacity to interact with people at a very young age without any prior experience or training. In a new study published by <a href="https://www.cell.com/">Cell Press</a>, experts report that some puppies communicate better with people from the start based on their <a href="https://www.earth.com/news/genetics-will-show-which-corals-can-resist-bleaching/">genetics</a>.

"We show that puppies will reciprocate human social gaze and successfully use information given by a human in a social context from a very young age and prior to extensive experience with humans," said Emily E. Bray of the University of Arizona. 

"For example, even before puppies have left their littermates to live one-on-one with their volunteer raisers, most of them are able to find hidden food by following a human point to the indicated location."

The researchers also found that more than 40 percent of the variation in a puppy's ability to follow a human's finger pointing is explained by the genes they have inherited. Genetics were also tied to variation in gazing behavior during a human-interest task.

"These are quite high numbers, much the same as estimates of the heritability of intelligence in our own species," said Bray. "All these findings suggest that dogs are biologically prepared for communication with humans."

Over the last decade, Bray and her colleagues have been conducting research with dogs in collaboration with Canine Companions, the largest service dog organization in the United States. 

The goal of the research is to gain a better understanding of how dogs think and solve problems. The experts also want to learn how a dog's abilities develop and change over time, as well as how genetics and individual experiences contribute.

To investigate whether a dog's capacity for communication can be explained by biology, the researchers took advantage of their access to hundreds of budding service dogs at the same early age. All of the dogs had an extremely similar rearing history and a known pedigree going back multiple generations. 

The team tested 375 eight-week-old puppies on the exact same tasks. The results showed that social communication through gestures and eye contact came naturally to puppies from the start. 

However, social communication cues only worked when a person initiated the interaction by speaking to the puppy in a high-pitched voice. Otherwise, the puppies did not usually look to people for answers in a task which involved food locked in a container.

"From a young age, dogs display human-like social skills, which have a strong genetic component, meaning these abilities have strong potential to undergo selection," said Bray. 

"Our findings might therefore point to an important piece of the domestication story, in that animals with a propensity for communication with our own species might have been selected for in the wolf populations that gave rise to dogs."

According to Bray, the next step in the research is to explore whether puppies can identify some of the specific genes that contribute to social behaviors. The team is currently collecting cognitive data and blood samples from adult dogs for a genome-wide association study, which will aim to identify genetic markers associated with social behaviors. 

The researchers will also follow up to see if performance on any of the social tasks at eight weeks predicts successful graduation as a service dog. 

The study is published in the journal <a href="https://www.cell.com/current-biology/home">Current Biology</a>.

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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

Puppies can communicate with people at a very young age

Puppies have the capacity to interact with people at a...

The world must honor its commitment to restore at least one billion degraded hectares of land in the next decade in order to address the triple threat of climate change, <a href="https://www.earth.com/news/changes-in-fish-biodiversity-lead-to-lower-nutritional-quality/">biodiversity</a> loss, and pollution. This is the message of a new report from the <a href="https://www.unep.org/">UN Environment Programme</a> (UNEP) and the <a href="http://www.fao.org/home/en/">Food and Agriculture Organization of the UN</a> (FAO).

According to the study authors, humanity is using about 1.6 times the amount of services that nature can provide sustainably. In order words, conservation efforts will not be enough to prevent large-scale ecosystem collapse and biodiversity loss. 

Worldwide, the costs of terrestrial restoration are estimated to reach at least $200 billion per year by 2030. The researchers found that every $1 invested in restoration creates up to $30 in economic benefits.

Restoration is urgently needed for terrestrial ecosystems including farmlands, forests, grasslands and savannahs. The experts report that some of the world's poorest communities are living across two billion degraded hectares of land.

"This report presents the case for why we must all throw our weight behind a global restoration effort. Drawing on the latest scientific evidence, it sets out the crucial role played by ecosystems, from forests and farmland to rivers and oceans, and it charts the losses that result from a poor stewardship of the planet," wrote UNEP Executive Director Inger Andersen and FAO Director-General QU Dongyu.

"Degradation is already affecting the well-being of an estimated 3.2 billion people - that is 40 percent of the world's population. Every single year we lose ecosystem services worth more than 10 percent of our global economic output."

Ecosystem restoration leads to "massive gains," explained the study authors, such as cleaner air and water, extreme weather mitigation, improved human health, and recovered biodiversity. The restoration process involves practices ranging from reforestation to re-wetting peatlands.

Actions that prevent, halt and reverse degradation are necessary to meet the Paris Agreement target of keeping global temperature rise below two degrees Celsius, noted the researchers. 

The experts also pointed out that restoration, if combined with the protection of natural ecosystems, may help avoid 60 percent of expected biodiversity extinctions. 

The study is published in the journal <a href="https://advances.sciencemag.org/">Science Advances</a>.

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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

Intense nature restoration needed to address the climate crisis

The world must honor its commitment to restore at least...

In a new study from <a href="https://www.cornell.edu/">Cornell University</a>, experts are describing how declining fish biodiversity can affect human <a href="https://www.earth.com/news/nutritional-value-of-crops-varies-by-location/">nutrition</a>. 

The research was focused on the Loreto region of the Peruvian Amazon, where inland fisheries serve as a critically important source of nutrition for 800,000 people. 

The findings are also applicable to fish biodiversity elsewhere. Worldwide, more than two billion people depend on fish as their primary source of animal-derived nutrients.

"Investing in safeguarding biodiversity can deliver both on maintaining ecosystem function and health, and on food security and fisheries sustainability," said study first author Sebastian Heilpern.

In Loreto, individuals eat about 110 pounds of fish annually. The experts report that this is one the highest fish consumption rates in the world and about half the amount of meat an average American consumes each year. 

According to catch data, Loreto residents eat a wide variety of fish, including about 60 species like large predatory catfish.  These migratory fish are declining due to overfishing and hydropower dams that block their paths. At the same time, however, the amount of fish caught has remained relatively consistent over time. 

"You have this pattern of biodiversity change but a constancy of biomass," said Heilpern. "We wanted to know: How does that affect nutrients that people get from the system?"

In collaboration with experts at Columbia University, the researchers took all these factors into account and ran extinction scenarios. They wanted to predict which species are more likely to go extinct, and which species are likely to replace those to compensate for a void in the ecosystem.

The model tracked seven essential animal-derived nutrients, including protein, iron, zinc, calcium and three omega-3 fatty acids, and simulated how changing fish stocks might affect nutrient levels across the population. 

The computer simulations revealed risks in the system regarding fish biodiversity. For example, when small sedentary fish species compensated for declines in large migratory species, fatty acids increased as zinc and iron supplies decreased. The region already suffers from high anemia rates.

"As you lose biodiversity, you have these tradeoffs that play out in terms of the aggregate quantity of nutrients," said Heilpern. "As you lose species, the system also becomes more and more risky to further shocks."

The study is published in the journal <a href="https://advances.sciencemag.org/">Science Advances</a>.

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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

Changes in fish biodiversity lead to lower nutritional quality

In a new study from Cornell University, experts are describing...

A new study from <a href="https://www.berkeley.edu/">UC Berkeley</a> reveals that young tyrannosaurs practiced their biting and strengthened their jaws before their adult <a href="https://www.earth.com/news/some-ancient-whales-had-both-teeth-and-baleen/">teeth</a> came in. The researchers determined that a juvenile Tyrannosaurus rex exerted a powerful bite force that was about one-sixth the force of an adult. 

Professor Jack Tseng teamed up with Professor Joseph Peterson of the University of Wisconsin to examine fossilized dinosaur bones that had teeth marks from a young tyrannosaur. 

The experts decided to replicate the bite marks and measure the force behind the bites. They developed a metal replica of a scimitar-shaped tooth of a 13-year-old T. rex, mounted it on a mechanical testing frame, and tried to crack a cow legbone with it.

"What we did, an actualistic study, is to say, 'Let's actually stab the thing with a tooth and see what it does,'" said Professor Peterson. "What we are finding is that our estimates are slightly different than other models, but they are within a close enough range - we are on the same page."

After 17 successful attempts to match the depth and shape of the bite marks on the fossils, the scientists determined that young tyrannosaurs exerted up to 5,641 newtons of force, somewhere between that of a hyena and a crocodile. By comparison, an adult T. rex applied about 35,000 newtons of force, while humans exert about 300 newtons.

Bite force measurements can help paleontologists understand the ecosystem in extinct animals lived, as well as which predators ate which prey.

"If you are up to almost 6,000 newtons of bite force, that places them in a slightly different weight class," said Professor Tseng. "By really refining our estimates of juvenile bite force, we can more succinctly place them in a part of the food web and think about how they may have played the role of a different kind of predator from their larger, adult parents."

The study reveals that juvenile T. rexes were developing their biting techniques and strengthening their jaw muscles to prepare for using their adult teeth.

"This actually gives us a little bit of a metric to help us gauge how quickly the bite force is changing from juvenile to adulthood, and something to compare with how the body is changing during that same period of time," said Professor Peterson. 

"Are they already crushing bone? No, but they are puncturing it. It allows us to get a better idea of how they are feeding, what they are eating. It is just adding more to that full picture of how animals like tyrannosaurs lived and grew and the roles that they played in that ecosystem."

Professor Tseng emphasized that there is no one number describing the bite force of any animal - it depends on how the creature bites and adjusts the prey in its mouth for the best leverage.

"They probably were not just chomping down. If you look at modern predators, even reptilian predators, sometimes there is adjustment. Maybe they are finding the most mechanically advantageous place, or the strongest tooth to make their bite," said Professor Tseng. 

"Presumably, there is some tuning involved before they make that bite, so they can literally take the best bite forward to make that kill or to damage whatever they are trying to get into."

The measurements provide a starting point for charting the increase in young tyrannosaurs' bite force as they mature.

"Just as you can do a growth curve for such an organism, you can also do a strength curve for their bite force - what was their bite force at 12 or 13 years old, what was it at 30, 35 or 40 years old. And what does that potentially mean about the role that those animals played in that ecosystem at the time?" said Professor Peterson. 

"What's cool about finding bite marks in bone from a juvenile tyrannosaur is that it is tells us that at 13 years old, they weren't capable of crushing bone yet, but they were already trying, they were puncturing bone, pretty deep. They are probably building up their strength as they get older."

The study is published in the journal <a href="https://peerj.com/">PeerJ</a>.

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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

Young tyrannosaurs practiced biting as they waited for adult teeth

A new study from UC Berkeley reveals that young tyrannosaurs...

A new study from <a href="https://www.ucsc.edu/">UC Santa Cruz</a> has revealed that over the past 1.2 million years, low-oxygen dead zones have repeatedly emerged in the subarctic North Pacific Ocean during warm <a href="https://www.earth.com/video/satellite-data-helps-scientists-predict-the-impacts-of-climate-change/">climates</a>. The findings provide critical information about the causes of low oxygen - or hypoxia - in the North Pacific, and will help to predict these conditions in the future.

"It is essential to understand whether climate change is pushing the oceans toward a 'tipping point' for abrupt and severe hypoxia that would destroy ecosystems, food sources, and economies," said study first author Karla Knudson.

The investigation was focused on the analysis of deep sediment cores from the Bering Sea. When organisms living in the seafloor sediments have been killed due to hypoxia, an orderly pattern of layers is preserved. Thus provides experts with a record of past low-oxygen events. 

At the end of the last ice age, a massive influx of fresh water into the ocean caused widespread hypoxia. The new study has produced the first records of earlier low-oxygen events.

"It doesn't take a huge perturbation like melting ice sheets for this to happen," said study co-author Professor Ana Christina Ravelo. "These abrupt hypoxic events are actually common in the geologic record, and they are not typically associated with deglaciation. They almost always happen during the warm interglacial periods, like the one we're in now."

While it remains unclear what triggers a hypoxic event, there is evidence that ocean warming, rising sea levels, and iron availability play a role. Hypoxia occurs after a surge in phytoplankton, which ultimately deplete the water of oxygen. 

"Our study shows that high sea levels, which occur during warm interglacial climates, contributed to these hypoxic events," said Knudson. "During high sea levels, dissolved iron from the flooded continental shelves can be transferred to the open ocean and promote intense phytoplankton growth in the surface waters."

Changes in ocean circulation - including intensified upwelling to bring more nutrients into the surface waters and stronger currents that could transfer iron from the continental shelf to the open ocean - likely play a critical role in triggering a hypoxic event, explained Knudson.

The sediment cores examined for the study were collected from a single site, which means the researchers do not know if the low-oxygen dead zones extended beyond the Bering Sea into other parts of the Pacific Ocean.

"We don't know how extensive they were, but we do know they were very intense and lasted longer than the deglaciation event that has been so well studied," said Professor Ravelo.

The findings raise new concerns about whether climate change and ocean warming will lead to a tipping point that will trigger widespread hypoxia in the North Pacific Ocean.

"The system is primed for this type of event happening," said Professor Ravelo. "We need to know how extensive they were, and we need to rethink how these events are triggered, because we now know that it doesn't take a huge perturbation. This study sets the stage for a lot of follow-up work."

The study is published in the journal <a href="https://advances.sciencemag.org/">Science Advances</a>.

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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

Warm climates linked to low-oxygen dead zones in the North Pacific

A new study from UC Santa Cruz has revealed that...

Oxygen levels are rapidly declining in the world's freshwater lakes. This trend, which is driven primarily by climate change, poses a threat to biodiversity and the quality of drinking <a href="https://www.earth.com/news/water-reservoirs-generate-much-higher-emissions-than-expected/">water</a>.
In lakes that were surveyed across the temperate zone, researchers found that oxygen levels have declined by 5.5 percent at the surface and by 18.6 percent in deep waters since 1980. 
Across some of the more nutrient-polluted lakes, the experts found that surface oxygen levels increased as water temperatures crossed a threshold favoring cyanobacteria.

"All complex life depends on oxygen. It's the support system for aquatic food webs. And when you start losing oxygen, you have the potential to lose species," said study co-author Professor Kevin Rose of the <a href="https://www.rpi.edu/">Rensselaer Polytechnic Institute</a>. "Lakes are losing oxygen 2.75 - 9.3 times faster than the oceans, a decline that will have impacts throughout the ecosystem."

The researchers analyzed more than 45,000 dissolved oxygen levels and temperature profiles that were collected from nearly 400 lakes worldwide. 

Study lead author Stephen F. Jane said the changes are concerning both for their potential impact on freshwater ecosystems and for what they suggest about environmental change in general.

"Lakes are indicators or 'sentinels' of environmental change and potential threats to the environment because they respond to signals from the surrounding landscape and atmosphere," said Jane.  

"We found that these disproportionally more biodiverse systems are changing rapidly, indicating the extent to which ongoing atmospheric changes have already impacted ecosystems."

The link between global warming and changing freshwater oxygen levels is controlled by mechanisms between surface water and deep water.

The study shows that as surface water temperatures increased by .38 degrees Centigrade per decade, dissolved oxygen concentrations declined by .11 milligrams per liter.

"Oxygen saturation, or the amount of oxygen that water can hold, goes down as temperatures go up. That's a known physical relationship and it explains most of the trend in surface oxygen that we see," said Professor Rose.

At the same time, some lakes experienced increasing dissolved oxygen concentrations as the temperature rose. According to the researchers, these lakes tended to be more polluted with nutrient-rich runoff from agricultural and developed watersheds and have high chlorophyll concentrations. 

"The fact that we're seeing increasing dissolved oxygen in those types of lakes is potentially an indicator of widespread increases in algal blooms, some of which produce toxins and are harmful," said Professor Rose. "Absent taxonomic data, however, we can't say that definitively, but nothing else we're aware of can explain this pattern."

In deeper waters, temperatures have remained largely stable. The loss of oxygen in this part of the lake follows a more complex path that is most likely tied to increasing surface water temperatures and a longer warm period each year. 

The combination of warming surface waters and stable deep-water temperatures means that the difference in density between these layers, known as "stratification," is increasing.

"The increase in stratification makes the mixing or renewal of oxygen from the atmosphere to deep waters more difficult and less frequent, and deep-water dissolved oxygen drops as a result," said Professor Rose. 

Some bacteria thrive in environments without oxygen, such as those that produce methane. This indicates that lakes have the potential to release more methane as they lose oxygen. 

"Ongoing research has shown that oxygen levels are declining rapidly in the world's oceans. This study now proves that the problem is even more severe in fresh waters, threatening our drinking water supplies and the delicate balance that enables complex freshwater ecosystems to thrive," said Dr. Curt Breneman. 

"We hope this finding brings greater urgency to efforts to address the progressively detrimental effects of climate change."

The study is published in the journal <a href="https://www.nature.com/">Nature</a>.

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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

Lakes are losing oxygen much faster than oceans

Oxygen levels are rapidly declining in the world's freshwater lakes....

In a new study from <a href="https://vt.edu/">Virginia Tech</a>, researchers have discovered a method that ducks use to balance water pressure in their feathers while diving. The investigation is part of a decade of research in fluid mechanics by Professor Jonathan Boreyko.

"I got this idea when I was at Duke University," said Professor Boreyko. "I had a really bad parking spot, but my walk took me right through the scenic Duke Gardens. I passed by ponds with lots of ducks, and I noticed that when a duck comes out of the water, they'd shake their feathers and water would fly off."

"I realized that what they were doing was a de-wetting transition, releasing water that was partially inside of their feathers. That was the germ of the idea. In my research, purely by coincidence, I was studying the same kind of thing. I realized that these transitions work only if the water isn't allowed to get all the way to the bottom of the porous feather structure."

Professor Boreyko was intrigued with this delicate balance, and was curious about the mechanisms that allow ducks to hold water in their feathers without sinking. In collaboration with PhD student Farzad Ahmadi, Professor Boreyko attempted to force a single drop of water through a natural duck feather.

"It didn't work," said Ahmadi. "Then we had the idea to build a pressure chamber to force a pool of water through several layers of feathers."

First, the researchers needed to ensure the water could only penetrate directly through the feathers, as opposed to simply leaking around their outer edges. They sealed each layer of feathers, leaving an area exposed in the same place on each surface.

Ultimately, the experts found that as the number of feather layers increases, the pressure required to push water through all the layers must also increase. This establishes a maximum pressure up to which feathers hold the water entering them, but do not allow the water to reach a duck's skin.

"Our hypothesis was to use multiple layers of feathers so that the water only comes in part way, but there are air pockets under that," explained Professor Boreyko. "As long as those air pockets are present, it prevents something called irreversible wetting. As long as the wetting is only partial, they can shake it out when they surface."

Ahmadi discovered that various species of ducks tend to have the exact number of feather layers needed to avoid irreversible wetting during their dives. At least one layer of feathers remains dry after a dive, and this allows the duck to shake out the water when it emerges.

Professor Boreyko believes there is potential for applying layered synthetic feathers to the exterior of a boat to make the boat travel more easily through the water.

"If we think of a ship moving over the water as an engineered bird, right now it's swimming naked," said Professor Boreyko. "We wonder if clothing the ship in feathers could impart the same enhancements that waterfowl benefit from."

The study is published in the journal ACS <a href="https://pubs.acs.org/journal/aamick">Applied Materials &amp; Interfaces</a>.

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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

How ducks balance water pressure while diving

In a new study from Virginia Tech, researchers have discovered...

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



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



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



Video Credit: American Chemical Society&nbsp;



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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.

Detecting mercury contamination with the tap of a finger

[sendtonews key="LvS8v8bp9z-2564889-12187" 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 Kainji Lake, a reservoir on the Niger River.



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



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



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



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



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



Video/ Image Credit: European Space Agency&nbsp;



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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.

Kainji Lake in north central Nigeria

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

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Today’s Video of the Day from <a href="https://www.igb.illinois.edu/">Carl R. Woese Institute for Genomic Biology</a> reveals how scientists can modify common crops like soybean, rice, and wheat to protect them from heat stress.



“We need to double crop production by 2050 to feed a growing global population, and not only are we not on track to do that, but climate change is further complicating things,” said Amanda Cavanagh, a lecturer at the University of Essex. 



The study is part of Realizing Increased Photosynthetic Efficiency (RIPE), an international research project that aims to develop food crops that turn the sun’s energy into food more efficiently.



“Using an engineering approach we designed multiple alternative metabolic pathways to photorespiration. Testing them in the field showed increases in productivity which led Amanda to significantly move the project forward by showing our engineered plants can withstand pretty extreme temperature stress,” said study co-author and RIPE researcher Paul South.&nbsp;



“As the climate changes and temperature stresses increase the pressure on our global food supply, farmers will need every tool available including engineering approaches like the synthetic biology used here to maintain safe and productive harvests.”



The experts tested plants modified to have more efficient photorespiration to see if they were better adapted to warmer temperatures.&nbsp;



The team found that the engineered plants produced 26 percent more biomass than the wild-type plants exposed to the same temperatures, and had 15 percent less yield loss under the higher temperatures.



Video Credit: Amanda Nguyen/University of Illinois



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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.

Designing crops that can beat the heat

[sendtonews key="QGPzYnXEtN-1712599-12187" type="single"] Today’s Video of the Day from Carl...

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Today’s Video of the Day from the <a href="https://www.acs.org/">American Chemical Society</a> explores the ability of salt to transform the way that foods and beverages taste. Salt is known to cover up undesirable flavors, such as bitterness in coffee or beer, but how exactly does sodium chloride change the taste of other compounds?



One previous study showed that, not only does salt suppress bitterness, but also enhances sweetness and sourness. Another study revealed that bitterness reduction by salt seems to be happening at the tongue receptor level as well as in the brain.&nbsp;



While it is known that salt taste is mediated by the presence of sodium channels in the form of taste buds, experts believe that there is also an unknown receptor responsible for how we taste salt that has not yet been identified.&nbsp;



Video Credit: ACS Reactions



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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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How does salt makes things taste better?

[sendtonews key="X0f6OHYoI4-2310561-12187" 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 Santiago, the capital city of Chile. The city is located in the center of the Santiago Metropolitan Region, which has a population of about eight million people.&nbsp;



'The weather of Santiago resembles the Mediterranean climate with dry and warm summers with temperatures reaching up to 35°C (from October to March) and cool and humid winters that can drop to 0°C (from April to September)."



"The city lies in the centre of the country’s central valley around 80 km from the Pacific Ocean to the west and borders Argentina to the east. A tiny part of Argentina is visible in the top-right corner of the image where the mountain crest of the Andes Mountains acts as a divider between the two countries," says ESA.



Video/ Image Credit: ESA



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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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Santiago, Chile in South America

[sendtonews key="JRaP49ISmm-2357509-12187" type="single"] Today’s Video of the Day from the...

Spiral,Galaxy,,Illustration,Of,Milky,Way

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Astronomers at <a href="https://www.jhu.edu/">Johns Hopkins University</a> have created an interactive map of the universe, including the actual position and real colors of 200,000 galaxies. The map allows the public to access data that was previously only available to scientists.



The map was developed using data collected by the Sloan Digital Sky Survey. For over two decades, a telescope in New Mexico was aimed at slightly different locations to capture the night sky.&nbsp;



"Growing up I was very inspired by astronomy pictures, stars, nebulae and galaxies, and now it's our time to create a new type of picture to inspire people," said map creator Brice Ménard, a professor at Johns Hopkins. "Astrophysicists around the world have been analyzing this data for years, leading to thousands of scientific papers and discoveries. But nobody took the time to create a map that is beautiful, scientifically accurate, and accessible to people who are not scientists. Our goal here is to show everybody what the universe really looks like."



"In this map, we are just a speck at the very bottom, just one pixel. And when I say we, I mean our galaxy, the Milky Way which has billions of stars and planets. We are used to seeing astronomical pictures showing one galaxy here, one galaxy there or perhaps a group of galaxies. But what this map shows is a very, very different scale."



"From this speck at the bottom, we are able to map out galaxies across the entire universe, and that says something about the power of science."



The <a href="https://mapoftheuniverse.net/">interactive map</a> is available online, where it can be downloaded for free.



Video Credit: Johns Hopkins&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.

Interactive map of the universe includes 200,000 galaxies

[sendtonews key="e4ZG0Jawp3-2374785-12187" type="single"] Astronomers at Johns Hopkins University have created...

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes the first comprehensive estimate of carbon density in the Saharan, Sahel, and Sudanian zones of Africa. In an effort to measure the amount of carbon stored across these drylands, a team of scientists used high-resolution satellite images and artificial intelligence to map nearly 10 billion individual trees. 



"The high spatial resolution (50 cm) combined with AI and field measurements used in this study is key to improving tree inventories in drylands," said Pierre Hiernaux, a French researcher working for NASA. "The ever-increasing availability of very high-resolution satellite imagery will make it possible to assess carbon pools and their dynamics at the individual tree level on a global scale."



"This study is exceptional because it is pioneering a type of approach that will revolutionize the monitoring of trees and forests on a global scale: in the short term, it will be possible to map the world's trees from the centre of the Amazon to our schoolyards," said <a href="https://www.inrae.fr/en">INRAE</a> researcher Jean-Pierre Wigneron.



"Many fields of application will become much more efficient and accurate, such as tracking carbon stocks, biodiversity, monitoring logging and protection against illegal forest degradation, in near real time.”



Video Credit: NASA Goddard&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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Remote sensing will revolutionize the way we monitor trees

[sendtonews key="EjmSP20gQK-2593093-12187" type="single"] Today's Video of the Day from NASA...

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Today's Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features Dublin, the capital and largest city of Ireland. Beyond its pub culture, Dublin is known as a modern culinary destination and a UNESCO City of Literature.



"Dublin is located near the midpoint of Ireland’s east coast in the province of Leinster. The city, which covers an area of around 115 square kilometers, is bordered by the Dublin Mountains, a low mountain range to the south, and is surrounded by flat farmland to the north and west," says ESA.



"The city straddles the River Liffey, which rises in the Wicklow Mountains and flows around 80 kilometers eastwards through the city of Dublin, in which it is canalised and bordered with quays. It then empties into Dublin Bay, an arm of the Irish Sea."



Dublin has an abundance of green spaces, including one of the largest enclosed public parks in any European capital city. Phoenix Park, which was originally formed as a royal hunting park in the 1660s, includes 707 hectares of green space.



Video Credit: ESA&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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The city of Dublin on Ireland's east coast

[sendtonews key="qjvhBOBnY8-2426650-12187" 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 the province of Zaragoza in northeast Spain. The image was captured by the Copernicus Sentinel-2 mission.



"Together with the provinces of Huesca and Teruel, Zaragoza formed the old kingdom of Aragon. Its capital, also called Zaragoza (not visible in this image) is home to around half of Aragon’s population," says ESA.



"The Ebro River can be seen winding its way through the province from west to east in this image. Between its source in the Cantabrian Mountains in the northwest and its delta on the Mediterranean coast, the Ebro River is fed by more than 200 tributaries as it flows 910 km across much of northern Spain."



Since rainfall is very scarce in this region, irrigation in the Ebro basin is critically important. In the valleys surrounding the Ebro River, many fields are used for growing crops such as corn, wheat, and barley.



Video/ Image Credit: ESA



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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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The province of Zaragoza in northeast Spain

[sendtonews key="oL4FnPTGCV-2384527-12187" type="single"] Today's Video of the Day from the...

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> features a visual dataset of.methane emissions from wetlands across the globe. Atmospheric methane levels have reached record highs in recent years, and wetlands are a major source of these emissions.&nbsp;



"Methane is an important greenhouse gas that contributes substantially to global warming. On a molecule by molecule basis, methane is much more efficient at trapping heat than carbon dioxide, the main driver of warming," says NASA.



"Though human activities, including agriculture, oil and natural gas production and use, and waste disposal, collectively contribute the majority of methane to the atmosphere, about a third of total methane emissions comes from wetlands."&nbsp;



According to NASA, understanding methane emissions from wetlands and other natural sources is critically important for scientists and policymakers who are working to combat climate change by reducing emissions from human activities.



Video Credit: NASA Goddard



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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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Wetlands are a major source of methane emissions

[sendtonews key="f8fukm28Vz-2491833-12187" type="single"] Today's Video of the Day from NASA...

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Today’s Video of the Day from <a href="https://earthobservatory.nasa.gov/">NASA Earth Observatory</a> reveals the evolution of the Columbia Glacier in southeastern Alaska. Columbia is among the fastest shrinking glaciers in the world, and the video documents its rapid retreat over the years.&nbsp;



Columbia Glacier is a large, multi-branched calving glacier that flows out of the Chugach Mountains to the Prince William Sound.&nbsp;



According to USGS, Columbia had a long history of stability prior to 1980, with a length 41 miles, and small, short-lived advances or retreats.



In the years since 1980, however, satellite images have captured Columbia’s alarming retreat. By using false-color images, scientists can distinguish between snow and ice, open water, vegetation, and rocky debris on the glacier’s surface.



The series of false-color images featured in today's video were acquired over the span of 35 years. You can see that by 2021, the glacier’s main branch had retreated about 15 miles from its initial position.



The Columbia Glacier has also lost more than 50 percent of its volume, mostly due to calving. <a href="https://www.earth.com/video/nasa-reveals-3d-visual-of-an-atmospheric-river/">NASA</a> reports that while climate change likely started the retreat, mechanical processes kept the disintegration going.



The NASA images are provided by Jesse Allen, Robert Simmon, Joshua Stevens, and Lauren Dauphin using data from Landsat satellites, from the U.S. Geological Survey, and data from MODIS on NASA’s Terra satellite. The structure of Columbia’s moraine played a large role in the stability of the glacier before 1980. 



Like other tidewater glaciers, the Columbia built up a moraine over time, and the mixture of ice and rock functioned like a dam keeping out the sea. It was supported on one end by the shoreline and by the underwater terminal moraine at the other.



Video Credit: NASA Earth Observatory/&nbsp; NASA’s Scientific Visualization Studio



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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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The rapid retreat of the Columbia Glacier

[sendtonews key="0879czfG3k-1785905-12187" type="single"] Today’s Video of the Day from NASA...

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Today’s Video of the Day from the <a href="https://www.esa.int/">European Space Agency</a> features the Pyrenees Mountains, which form a natural boundary between France and Spain in southwest Europe.



The mountain range is 430 kilometers in length. It stretches from the Mediterranean Sea on the east to the Atlantic Ocean on the west.



At an elevation of 3404 meters, Pico de Aneto is the highest mountain peak in the Pyrenees, and the third-highest peak in Spain. Pico de Aneto is located in the Posets-Maladeta Natural Park, which spans more than 82,000 acres.&nbsp;



"Geological studies have revealed that the Pyrenees Mountains have been around for longer than the Alps, with their sediments first deposited in coastal basins during the Paleozoic and Mesozoic eras," reports ESA.



"The entire mountain range formed due to the upwelling of large sedimentary rocks by the collision of the Iberian and the Eurasian plate around 100 to 150 million years ago, followed by intense erosion from ice and water."



The western Pyrenees receive more precipitation due to moisture blowing in from the Atlantic Ocean. The mountain range contains many lakes, several small glaciers, and some of the highest waterfalls in Europe.



Video &amp; Image Credit: ESA



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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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The Pyrenees Mountains in southwest Europe

[sendtonews key="6HyfrAJTBI-1831843-12187" type="single"] Today’s Video of the Day from the...

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Today’s Video of the Day from <a href="https://www.stowers.org/">Stowers Institute for Medical Research</a> describes why experts are studying zebrafish to gain a better understanding of how the immune system responds to injury. Zebrafish have the ability to repair and regenerate organs.



“Organ regeneration offers an exciting opportunity for studying the immune system and to inquire why some species can regenerate organs like the heart or missing limbs while others like humans cannot,” explained Dr. Tatjana Piotrowski.



Zebrafish sensory organ hair cells are an ideal system to investigate the pathways and cell types involved in regeneration since they are easily destroyed with antibiotics and begin regenerating within five hours. This enabled the researchers to identify the exact timing and genetic programs for each anti-inflammatory macrophage activation state.&nbsp;



“Our hypothesis is that human macrophages do not receive the proper chemical activation 'cocktail' to instruct pro-regenerative processes,” said Dr. Nicolas Denans. “Identifying the molecular recipe of macrophage activation in zebrafish may one day enable us to design regenerative immunotherapies in humans.”&nbsp;&nbsp;&nbsp;



“The new evidence is a valuable resource for comparative studies on the genetic programs involved in macrophage-mediated repair and regeneration. In other words, different types of injuries may induce different kinds of inflammatory responses. We want to decipher whether this 'language' is universal or if there are a variety of dialects."



Video Credit: Stowers Institute for Medical Research&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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How the immune system responds to injury

[sendtonews key="0dEcERCq61-2283382-12187" type="single"] Today’s Video of the Day from Stowers...

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes how record-breaking heat expressed itself around the world in 2022.



Scientists have determined that 2022 was the 5th warmest year since 1880. Furthermore, the last nine consecutive years have been the warmest on record.



From devastating floods and wildfires to natural disasters like Hurricane Ian, 2022 showed us yet again how a warming climate affects people across the globe.&nbsp;



"As we look back at 20:22 and years past, we see that each year we better understand the challenges we face and how important it is to meet them," says NASA.



Video/ Image Credit: NASA Goddard



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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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2022 illustrated the consequences of a warming climate

[sendtonews key="3UUsNkFOuS-2487333-12187" type="single"] Today's Video of the Day from NASA...

Earth,Like,Exoplanet,3d,Render

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Today's Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes two exoplanets that are orbiting a star 218 light-years away. A team of researchers led by the University of Montreal has found evidence that these planets are "water worlds."



The experts used data from NASA’s Hubble and Spitzer Space Telescopes. They discovered that exoplanets Kepler-138 c and Kepler-138 could be composed largely of water.



"We previously thought that planets that were a bit larger than Earth were big balls of metal and rock, like scaled-up versions of Earth, and that's why we called them super-Earths," explained study co-author Björn Benneke.&nbsp;



"However, we have now shown that these two planets, Kepler-138 c and d, are quite different in nature and that a big fraction of their entire volume is likely composed of water. It is the best evidence yet for water worlds, a type of planet that was theorized by astronomers to exist for a long time."



Video Credit: NASA Goddard



Image Credit: NASA, ESA, and Leah Hustak (STScI)



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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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Two distant planets may be "water worlds"

[sendtonews key="QIoVYJqRBi-2434608-12187" type="single"] Today's Video of the Day from NASA...

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Satellites reveal how Earth's systems are interconnected Today’s Video of the Day from <a href="https://www.nasa.gov/goddard">NASA Goddard</a> describes Earth’s interconnected systems, and how this network is affected by rising temperatures.&nbsp;



During 2020, average global temperatures matched the hottest year on record. The hurricane season was also record-breaking, with many of the storms intensifying at extraordinary speeds. Hot water in the ocean is fuel for hurricanes. The satellite data shows that it's all one interconnected system showing how Satellites reveal how Earth's systems are interconnected.



According to NASA, dust swept up from Northern Africa plays a major role in the formation of hurricanes, and is also a key source of fertilization in the Amazon rainforest. As a result of<a href="https://www.earth.com/news/seagrass-wasting-disease-is-fueled-by-climate-change/"> climate</a> change, dust plumes are expected to decline, which will have an effect on vegetation far away.&nbsp;



Images from Earth-observing satellites show how the world’s plant life is affected by natural disasters, fires, and deforestation. Satellites also reveal how widespread changes in vegetation impact waterways,&nbsp; the climate, air quality. Satellites communicate by using radio waves to send signals to the antennas on the Earth. "Earth From Space" is a groundbreaking two-hour special that reveals a spectacular new space-based vision of our planet. 



Video Credit: NASA Goddard&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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Satellites reveal how Earth's systems are interconnected

[sendtonews key="JbW4VsY53O-1632195-12187" type="single"] Satellites reveal how Earth's systems are interconnected...

Today’s Video of the Day from the <a href="https://welcome.miami.edu/">University of Miami</a> Rosenstiel School of Marine and Atmospheric Science explores how changes in water temperatures have affected tiger shark habitats and movements in the North Atlantic Ocean. The study reveals that rising temperatures have caused the sharks to shift toward the poles over the past 40 years.



“Tiger shark annual migrations have expanded poleward, paralleling rising water temperatures,” explained study lead author Neil Hammerschlag. “These results have consequences for tiger shark conservation, since shifts in their movements outside of marine protected areas may leave them more vulnerable to commercial fishing.”



The researchers analyzed nine years of tracking data from satellite-tagged tiger sharks, combined with four decades of conventional tag and recapture data provided by National Oceanic and Atmospheric Administration (NOAA) Cooperative Shark Tagging Program.



The experts found that during the last decade of record heat, for every one-degree Celsius increase in water temperatures, tiger sharks migrated further poleward by over 400 kilometers. They also migrated two weeks earlier than usual to waters off the northeastern coast of the United States.



“Given their role as apex predators, these changes to tiger shark movements may alter predator-prey interactions, leading to ecological imbalances, and more frequent encounters with humans,” concluded Professor Hammerschlag.



Video Credit: University of Miami Rosenstiel School of Marine and Atmospheric Science



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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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Tiger sharks are shifting poleward as temperatures rise

Today’s Video of the Day from the University of Miami...