ScienceAlert – Latest

ScienceAlert – Latest
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Anxious About Climate Change? This Interactive Atlas Lets You Explore The Future
<p>The latest <a href=”” target=”_blank” title=”climate change”>climate change</a> report from the UN Intergovernmental Panel on Climate Change (IPCC) makes for <a href=”” target=”_blank” rel=”noopener noreferrer”>grim reading</a>: our planet is heating up more quickly than previously predicted, and there’s no doubt that human activity is to blame.</p>
<p>Unless some seismic shifts in behavior and policy take place <a href=”” target=”_blank” rel=”noopener noreferrer”>over the next four years</a>, we’ve got no chance of limiting global warming to the 1.5 °C target put on record by the <a href=”” target=”_blank” rel=”noopener noreferrer”>Paris Agreement</a> in 2015.</p><p>Anything higher than that, and all the consequences of climate change get much worse: oceans rising higher, weather systems collapsing, more parts of the world becoming inhospitable, and extreme events like hurricanes and wildfires <a href=”” target=”_blank” rel=”noopener noreferrer”>becoming even more common</a>.</p><p>While we know that with enough work and political will, humanity can plot its way out&nbsp;of the worst-case scenario, a lot of change needs to happen very fast.</p><blockquote class=”twitter-tweet tw-align-center” readability=”11.466666666667″>
<p dir=”ltr” lang=”en”>The IPCC report is coming out tomorrow. As a climate scientist, I’d like you to know: I don’t have hope. </p><p>I have something better: certainty. </p><p>We know exactly what’s causing climate change. We can absolutely 1) avoid the worst and 2) build a better world in the process.</p>
— Kate Marvel (@DrKateMarvel) <a href=””>August 8, 2021</a></blockquote><p>To give us all a better idea of what lies ahead, the IPCC has also launched <a href=”” target=”_blank” rel=”noopener noreferrer”>a super-detailed, interactive map</a>, breaking down possible climate change scenarios across the globe. You can zoom right into your part of the planet and see what’s likely to change before the end of the century.</p><p>Whether you want to look up the rainfall over Africa, the top temperatures in the Arctic, or the sea level rise around Australia in the years to come, this atlas can help. There’s a wealth of data to look through, all presented in a clear and easy-to-read way.</p><p>You should see a tutorial when you open the map up for the first time, but in general if you just click around the atlas, it won’t take you long to figure out how it works.</p><p><span class=” wf_caption”><img src=”” alt=”A screenshot of the IPCC Atlas interface” width=”700″><span>(IPCC)</span></span></p><p>Under <em>Dataset</em> you can pick from a variety of the best climate models, including the latest and most detailed, <a href=”″ target=”_blank” rel=”noopener noreferrer”>CMIP6</a>. The <em>Variable</em> menu is where you set what you want to look at (temperature, precipitation, and so on), and under <em>Value &amp; Period</em> you can switch between spans of years and predicted scenarios (such as 3 °C or 4 °C of warming).</p><p>As well as checking out what’s going to happen in the future, you’re able to dip into the recent past too, to check how the statistics compare. Plus, besides checking your own particular area, you can also narrow down the results by the time of year as well.</p><p>The team behind the atlas has gone to great lengths to be as comprehensive as possible: When you bring up various graphs and forecasts, the areas of uncertainty are clearly marked, with more definite predictions in darker colors.</p><p>All the data that’s displayed can be downloaded and shared as well – perfect for getting your neighbors and relatives up to speed on where the planet is headed.</p><p>If we’re going to head off the worst of climate change, we’re going to need all the data we can get, and this map brings a wealth of it right to your fingertips.</p><p><a href=”” target=”_blank” rel=”noopener noreferrer”>You can peruse the IPCC interactive atlas here</a>.</p>
Wed, 11 Aug 2021 18:00:01 +0000 David Nield

Apes Have Been Observed Starting And Ending Interactions Just Like Humans Do
<div><img src=”” class=”ff-og-image-inserted”></div><p>When humans interact with each other, we tend to follow invisible rules. We may greet each other with ‘hi, how are you?’ to indicate the start of a conversation; once someone starts using phrases like ‘oh, it was nice to see you’, we know the chat has reached its end.&nbsp;</p>
<p>Until now, we thought we were the only species that conducted these conversational niceties. As it turns out, some of our close primate relatives do too.&nbsp;</p><p>In a new study, researchers have <a href=”″>documented</a> apes purposefully using signals to start and end their interactions.</p><p>The team analyzed 1,242 interactions within groups of bonobos and chimpanzees in zoos, finding that the apes would frequently gaze and use signals to initiate or end exchanges – something we typically associate with human interactions.</p><p>The authors believe these findings contribute to a better understanding of the origin and evolution of ‘joint commitment’ as a process not just in humans, but in great apes more broadly; this refers to processes where we share intentions and work together towards common goals.</p><p>”Joint commitment as process refers to the exchange of signals necessary for would-be co-participants to&nbsp;arrive at the mutual belief that they are committed to a course of action where each has his or her part to&nbsp;play,” the team <a href=”″ target=”_blank” rel=”noopener noreferrer”>writes in their paper</a>. Starting a conversation by exchanging greetings is a simple example of this.</p><p>”Behavior doesn’t fossilize. You can’t dig up bones to look at how behavior has evolved. But you can study our closest living relatives: great apes like chimpanzees and bonobos,”&nbsp;<a href=”″>says</a>&nbsp;Raphaela Heesen, a social cognition researcher at Durham University, and co-author of the study.</p><p>In the study, bonobos shared entry signals and a mutual gaze prior to playing 90 percent of the time, while chimps did so 69 percent of the time.</p><p>Exiting signals were even more common, with 92 percent of bonobo and 86 percent of chimp interactions involving an exit communication. The various types of signalling included gestures like touching each other, holding hands, butting heads, or gazing at each, before and after interactions like grooming or play.</p><p><iframe src=”” width=”700″ height=”414″ allowfullscreen=”allowfullscreen”>[embedded content]</iframe></p><p>The study, which was published in <em>iScience</em>, also looked at factors such as the closeness of relationships, and the power dynamics between the apes that were interacting. For bonobos, the closer they were to each other socially, the shorter the lengths of their entry and exit phases, or they didn’t even bother.&nbsp;</p><p>The authors believe this mirrors how humans tend to communicate with one another.</p><p>”When you’re interacting with a good friend, you’re less likely to put in a lot of effort in communicating politely,”&nbsp;<a href=”″>notes</a>&nbsp;Heesen.&nbsp;</p><p>Conversely, the strength of social bonds and friendships didn’t seem to affect entries and exits to interactions in chimpanzees. This could be down to the authoritarian power hierarchies observed in chimps, whereas bonobo groups appear to be more egalitarian in their social structure.</p><p>”This ability [to share intentions] has been suggested to be at the heart of human nature,” <a href=”″ target=”_blank” rel=”noopener noreferrer”>says Heesen</a>. “Whether this type of communication is present in other species will also be interesting to study in the future.”</p><p>With this research in mind, if you ever encounter a great ape, you might not want to skip the pleasantries.&nbsp;</p><p>The research was published in the journal <em><a href=””>iScience</a></em>.&nbsp;</p>
Wed, 11 Aug 2021 15:00:01 +0000 Conor Feehly

You Won’t Believe These 10 Incredible Photos Are Pictures of Earth
<p>The&nbsp;<a href=”” data-component-tracked=”1″>Landsat project</a>, a joint venture between NASA and the US Geological Survey, is the longest continuous space-based record of&nbsp;<a href=”” data-component-tracked=”1″>Earth</a>&nbsp;in existence. A total of eight Landsat satellites have been launched into space since 1972, with a ninth set to launch in September.</p>
<p>In that time, the satellites have captured more than 9 million images of the planet’s surface, which have been used in more than 18,000 scientific papers, according to&nbsp;<a href=”” data-component-tracked=”1″>NASA’s Earth Observatory</a>.&nbsp;</p><p>To celebrate the upcoming 50th anniversary of the Landsat project, the Earth Observatory is running a public competition to choose the best Landsat pictures of all time.</p><p>People can pick their favorites from 32 final images – so that’s exactly what we’ve done.</p><h2 id=”winds-trigger-pond-growth-xa0″>Winds trigger pond growth&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”(Joshua Stevens/NASA Earth Observatory)” width=”700″><span>The Atchafalaya Delta. (Joshua Stevens/NASA Earth Observatory)</span></span></p><p>This striking image of the Atchafalaya Delta in Louisiana was taken by Landsat 8 on 1 December, 2016.</p><p>It is a false-color image, meaning that the colors have been altered, which “emphasizes the difference between land and water, while allowing viewers to observe waterborne sediment,” according to the&nbsp;<a href=”” data-component-tracked=”1″>Earth Observatory</a>.</p><p>It is one of 10,000 Landsat images of the region taken between 1982 and 2016, which were used in a study published in&nbsp;<a href=”″ data-component-tracked=”1″>Geophysical Research Letters</a>&nbsp;that looked at the role wind plays in pond expansion on the Mississippi River Delta Plain.&nbsp;</p><h2 id=”where-the-dunes-end-xa0″>Where the dunes end&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”(Image credit: Joshua Stevens/NASA Earth Observatory)” width=”700″><span>Namib-Naukluft Park. (Joshua Stevens/NASA Earth Observatory)</span></span></p><p>This image, captured by Landsat 8 on 13 November 2019, shows the striking color contrast between the Namib Sand Sea, the world’s only coastal desert, covering more than 10,000 square miles (26,000 square kilometers), and the rocky mountains of the Namib-Naukluft Park, both in Namibia.</p><p>The&nbsp;<a href=”” data-component-tracked=”1″>sand</a>&nbsp;appears a reddish-orange color due to the presence of&nbsp;<a href=”” data-component-tracked=”1″>iron</a>&nbsp;oxide. The Kuiseb River, which is prone to flooding, stops the sand from spilling over into the mountains, according to the&nbsp;<a href=”” data-component-tracked=”1″>Earth Observatory</a>.&nbsp;</p><h2 id=”yukon-kuskokwim-in-colorful-transition-xa0″>Yukon-Kuskokwim in colorful transition&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”The Yukon-Kuskokwim Delta. (Joshua Stevens/NASA Earth Observatory)” width=”700″><span>The Yukon-Kuskokwim Delta. (Joshua Stevens/NASA Earth Observatory)</span></span></p><p>This image of the Yukon-Kuskokwim Delta, where the Yukon River spills into the Bering Sea in Alaska, was taken on 19 May 2021, by Landsat 8. The colors on land have been enhanced in this photo: Green highlights the area of live vegetation; yellow is bare ground; and light brown is dead vegetation.</p><p>”The Yukon Delta is an exceptionally vivid landscape, whether viewed from the ground, from the air or from low-Earth orbit,” Gerald Frost, a scientist at ABR, Inc – Environmental Research and Services in Alaska, told the&nbsp;<a href=”” data-component-tracked=”1″>Earth Observatory</a>.&nbsp;</p><h2 id=”from-russia-with-questions-xa0″>From Russia with questions&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”AmpFX5cbkgnEnQqAaMbSa5 970 80″ width=”700″><span>The Markha River. (Joshua Stevens/NASA Earth Observatory)</span></span></p><p>Landsat 8 captured this photo of bizarre ripples in the hills surrounding the Markha River in northern Russia on 29 October 2020. The alternating light and dark stripes are visible throughout the year but are more pronounced in winter.</p><p>Scientists aren’t exactly sure why the pattern exists. It could have emerged because of the constant freezing and melting of permafrost or due to some kind of unique erosion from rainfall or snowmelt, but NASA remains unsure,&nbsp;<a href=”” data-component-tracked=”1″>Live Science previously reported</a>.&nbsp;</p><h2 id=”ginseng-farms-in-northern-china-xa0″>Ginseng farms in northern China&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”(Joshua Stevens/NASA Earth Observatory)” width=”700″><span>Farmland in Heilongjiang province. (Joshua Stevens/NASA Earth Observatory)</span></span></p><p>On 25 September 2017, Landsat 8 captured this image of blue, purple and yellow structures covering large areas of farmland in Heilongjiang province in northeastern China.</p><p>The structures are plastic shade covers used to grow ginseng – a slow-growing root plant that looks very similar to ginger but can’t &nbsp;survive in direct sunlight. In many Asian countries, ginseng is believed to have a wide range of medicinal properties, and farming the plant has become a multi-billion dollar business, according to the&nbsp;<a href=”” data-component-tracked=”1″>Earth Observatory</a>.&nbsp;</p><h2 id=”painting-pennsylvania-hills-xa0″>Painting Pennsylvania hills&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”(Joshua Stevens/NASA Earth Observatory)” width=”700″><span>Tectonic plates in central Pennsylvania. (Joshua Stevens/NASA Earth Observatory)</span></span></p><p>This impressive image combines a satellite image of folded mountains – warped mountains formed at the boundary between two&nbsp;<a href=”” data-component-tracked=”1″>tectonic plates</a>&nbsp;- in central Pennsylvania, taken by Landsat 8 on 9 November, 2020, with a digital elevation model to highlight the topography of the area.</p><p>The mountains are part of a unique geological region of the Appalachian Mountains, known as the&nbsp;<a href=”” data-component-tracked=”1″>Valley and Ridge province</a>, which stretches from New York to Alabama. As well as showing off the unusual shapes of the mountains, this natural-color image also reveals the autumnal palette of colors created as leaves turn red and begin to fall from deciduous trees, according to the&nbsp;<a href=”” data-component-tracked=”1″>Earth Observatory</a>.&nbsp;</p><h2 id=”jason-and-the-bloomonauts-xa0″>Jason and the Bloomonauts&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”(Joshua Stevens/NASA Earth Observatory)” width=”700″><span>(Joshua Stevens/NASA Earth Observatory)</span></span></p><p>This stunning natural-color image of an algal bloom surrounding the western Jason Islands, an archipelago in the South Atlantic Ocean, was taken by Landsat 8 on 18 October, 2020.</p><p>The milky blue swirls are caused by the rapid growth of photosynthetic&nbsp;<a href=”” data-component-tracked=”1″>algae</a>, which thrive in the nutrient-rich waters that have been enriched by the Malvinas Current – a spin-off of the Circumpolar Current of the Southern Ocean, which draws up nutrients from the deep ocean, according to the&nbsp;<a href=”” data-component-tracked=”1″>Earth Observatory</a>.&nbsp;</p><h2 id=”lake-natron-xa0″>Lake Natron&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”(Joshua Stevens/NASA Earth Observatory)” width=”700″><span>(Joshua Stevens/NASA Earth Observatory)</span></span></p><p>This striking aerial photo of the blood-red Lake Natron in Tanzania was taken by Landsat 8 on 6 March 2017. Lake Natron is an alkaline lake. The dramatic color is fueled by molten mixtures of&nbsp;<a href=”” data-component-tracked=”1″>sodium</a>&nbsp;carbonate and&nbsp;<a href=”” data-component-tracked=”1″>calcium</a>&nbsp;carbonate salts from nearby&nbsp;<a href=”” data-component-tracked=”1″>volcanoes</a>&nbsp;that enter the water via hot springs.</p><p>With temperatures averaging 104 degrees Fahrenheit (40 degrees Celsius) and less than 19.7 inches (500 millimeters) of rainfall a year, it is one of the harshest environments on Earth, according to the&nbsp;<a href=”” data-component-tracked=”1″>Earth Observatory</a>.&nbsp;</p><h2 id=”icy-art-in-the-sannikov-strait-xa0″>Icy art in the Sannikov Strait&nbsp;&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”(Lauren Dauphin/NASA Earth Observatory)” width=”700″><span>(Lauren Dauphin/NASA Earth Observatory)</span></span></p><p>This fascinating photo of the Sannikov Strait – a body of water sandwiched between the New Siberian Islands north of mainland Russia – was taken by Landsat 8 on 5 June 2016.</p><p>The strait connects the Laptev Sea to the west with the Siberian Sea to the east; the strait remains covered in ice for the majority of the year,&nbsp;<a href=”” data-component-tracked=”1″>Live Science previously reported</a>. This photo shows the ice sheet breaking apart during the summer melt and creating a picturesque panorama of icy puzzle pieces.&nbsp;</p><h2 id=”xa0-where-batteries-begin-xa0″>Where batteries begin&nbsp;</h2><p><span class=” wf_caption”><img src=”” alt=”(Lauren Dauphin/NASA Earth Observatory)” width=”700″><span>(Lauren Dauphin/NASA Earth Observatory)</span></span></p><p>This colorful array of cuboids found in the Salar de Atacama – a salt flat surrounded by mountains in Chile – is actually the world’s largest&nbsp;<a href=”” data-component-tracked=”1″>lithium</a>&nbsp;plant, photographed by Landsat 8 on 4 November 2018.</p><p>Lithium is the main component of batteries needed to power our cars, cellphones, laptops and other rechargeable gadgets.</p><p>This plant pumps lithium-rich brine from below the surface and diverts it into evaporation pools, where the sun evaporates the water away, leaving pure lithium. The different colors are a result of the varying stages of the evaporating process, according to the&nbsp;<a href=”” data-component-tracked=”1″>Earth Observatory</a>.&nbsp;</p><p><strong>This article was originally published by <a href=””>Live Science</a>. Read the original article <a href=”” target=”_blank” rel=”noopener noreferrer”>here</a>.</strong></p>
Wed, 11 Aug 2021 07:44:17 +0000 Harry Baker, Live Science

COVID-19 Could Disrupt The Fight-or-Flight Response For Months, Study Suggests
<div><img src=”” class=”ff-og-image-inserted”></div><p>Young people who contract <a href=”” target=”_blank” title=”COVID-19″>COVID-19</a>, but who are otherwise healthy, show a disrupted fight-or-flight response that can last for months, according to new research.</p><p>In a six-month study monitoring 30 participants (16 of whom had contracted COVID-19), what researchers ultimately found falls largely in line with what many <a href=”” target=”_blank” rel=”noopener noreferrer”>COVID-19 ‘long haulers'</a> have been reporting to date.</p>
<p>Even while at rest, the nerves of young, COVID-19 survivors seem to work much harder than those who have not contracted the <a href=”” target=”_blank” title=”virus”>virus</a>.</p><p>In the study, a tiny electrode, inserted into the back of the knee, found reduced electrical activity in the muscles of those recovering from COVID-19.</p><p>These nerves receive messages from the sympathetic nervous system, which controls our fight-or-flight response, and for those who are recovering from the virus, this system appears abnormally active.</p><p>When going from lying down to tilted upright, for instance, the 16 COVID survivors showed elevated sympathetic activity, followed by an exaggerated heart rate response to the change in blood pressure.</p><p>It’s worth noting that this is only a small study,&nbsp;but even though the cohort was tiny, the&nbsp;findings do match up with&nbsp;<a href=”” target=”_blank” rel=”noopener noreferrer”>recent reports</a> suggesting many long haulers – people experiencing COVID-19 symptoms for months on end – are unable to keep their standing heart rate from beating out of control.</p><p>In other cases, however, the sympathetic nervous system of COVID-19 patients appears to be seriously under-active.</p><p>When the young participants stuck their hands in ice cold water, for example, their muscle nerve activity was lower than normal and the participants reported feeling substantially less pain than 14 healthy control subjects.</p><p>This isn’t a perfect comparison; it would be better to have tested survivors before and after contracting COVID-19, to see how their personal physiological responses might have changed over time. But given the surprising nature of this disease, using healthy participants who have not been exposed to the virus as a control is our next best option.</p><p>The results suggest <a href=”” target=”_blank” title=”SARS-CoV-2″>SARS-CoV-2</a> can somehow throw off the sympathetic nervous system, making it work too hard at rest and not hard enough during stressful situations, even among young people who are not as vulnerable to severe illness.</p><p>”If similar autonomic dysregulation, like that found here in young individuals, is present in older adults following SARS-CoV-2 infection,” the authors <a href=”″ target=”_blank” rel=”noopener noreferrer”>write</a>, “there may be substantial adverse implications for cardiovascular health.”</p><p>But for now, there’s just a whole lot of ‘ifs’, with not a whole lot of answers.</p><p>Higher resting activity in the sympathetic nervous system is known to increase a person’s heart rate and cardiac output, possibly putting stress on the cardiovascular system over time. But this is the first study to examine nervous system activity after SARS-CoV-2 infects the body.</p><p>Today, some 200 million people around the world have survived COVID-19, and if the new findings can be verified among much larger cohorts, then it means millions of people might have suffered from an abnormal sympathetic nervous system for months during their recovery.</p><p>How long those symptoms lasted before they cleared up remains unknown. The current study tracked participants for six months, but some long-haulers are still showing high standing heart rates and other cardiovascular issues long after that.</p><p>The authors are not sure what it is about SARS-CoV-2 that is disrupting the sympathetic nervous system of patients to such a degree, but they suspect oxidative stress and inflammation might be to blame.</p><p>High levels of sympathetic nervous activity in the muscles have been linked to increased arterial stiffness in the past, and interestingly enough, young adults with COVID-19 <a href=”” target=”_blank” rel=”noopener noreferrer”>have shown greater stiffness in their arteries</a> up to three months after testing positive for the virus.</p><p>This reduced elasticity can change how much oxygen is being carried to a person’s head or heart, and this, in turn, could be kickstarting the body’s fight-or-flight response. On the other hand, inflammation, brought on by the immune system, could also be triggering the sympathetic nervous system.</p><p>”If, in fact, our [COVID positive] participants also have increased resting vessel diameters, the higher resting [muscle sympathetic nervous system activity] could serve as an acute adaptation to systemic vasodilation,” the authors <a href=”″ target=”_blank” rel=”noopener noreferrer”>suggest</a>.</p><p>”Certainly, we are limited in these interpretations given the cross-sectional nature and short time-frame of this study.”</p><p>It’s hard to conclude much from the results, but the implications are worrisome. Given the possible health issues that can arise from an overactive sympathetic nervous system, it’s important we find out more.</p><p>The study was published in the <a href=”″ target=”_blank” rel=”noopener noreferrer”><em>Journal of Physiology</em></a>.</p>
Wed, 11 Aug 2021 07:30:20 +0000 Carly Cassella

Epic Nova Eruption From Rare Star Is So Bright You Can See It With The Naked Eye
<div><img src=”” class=”ff-og-image-inserted”></div><p>If you look carefully into the night sky, you might see a star that wasn’t visible last week.</p><p>In the equatorial constellation of Ophiuchus, a star named <a href=””>RS Ophiuchi</a> about <a href=”″>4,566 light-years</a> away has just had an epic eruption. This nova was so bright that the star is now visible to the naked eye, at a magnitude of around 4.8 – a whopping seven magnitudes brighter than its usual 12th magnitude dimness.</p>
<p>Novae are rare enough to spot at the best of times, but what makes this occasion so special is the rarity of the star. RS Ophiuchi is what is known as a recurrent nova – a star that erupts periodically – and only 10 of these stars have ever been discovered in the Milky Way.</p><p>RS Ophiuchi typically erupts every 15 years or so. Its last nova was in 2006, so the new burst is right on schedule, and was first reported on 8 August 2021 <a href=”″>by Irish amateur astronomer Keith Geary</a>. That detection was rapidly followed by reports of <a href=”″>others around the world</a>.</p><blockquote class=”twitter-tweet tw-align-center” readability=”9.84″>
<p dir=”ltr” lang=”en”>RS Ophiuchi OUTBURST<br>Taken by Ernesto Guido, Marco Rocchetto &amp; Adriano Valvasori on August 9, 2021 @ Remotely from Australia through TELESCOPE LIVE network<a href=””></a></p><p>recurrent nova RS Oph is in Outburst. The last large outburst of RS Oph occurred in Feb. 2006, → <a href=””></a></p>
— mizuho kai (@mizuho73700856) <a href=””>August 9, 2021</a></blockquote><p>What causes the star’s repeated novae is overenthusiastic snacking. RS Ophiuchi is a binary star, a white dwarf in close orbit with a red giant. As the two whirl around each other, material – primarily hydrogen – is siphoned off the red giant by the smaller, denser white dwarf.</p><p>This hydrogen accumulates on the white dwarf’s surface, where it heats up. Periodically, the mass becomes so great that the pressure and temperature at the bottom of the layer is sufficient to trigger a thermonuclear explosion, violently expelling the excess material into space. This is the nova.</p><p>According to <a href=”″>spectroscopic observations of the star</a>, the brightening is consistent with a nova – so violent that the material is being ejected into space at velocities around 2,600 kilometers per second.</p><p>The Fermi Gamma Ray Telescope also detected a gamma-ray source at the time and location of the nova, confirming that an <a href=”″>outburst was indeed taking place</a>.</p><p>If the white dwarf accumulates so much mass that it exceeds a critical mass threshold called the Chandrasekhar limit, it will become unstable and explode in a Type Ia supernova, which will spell the end of the binary.</p><p>That may happen to RS Ophiuchi one day, but it’s not today – the two stars will live on to continue their spectacular dance, and explode another day.</p><blockquote class=”twitter-tweet tw-align-center” readability=”5.8932806324111″>
<p dir=”ltr” lang=”en”>Recurrent Nova RS Ophiuchi is currently in outburst at magnitude +4.5/+5.0 over the past weekend… the last outburst was 2006. Look for the novae due south at dusk. More to come! <a href=””></a></p>
— Dave Dickinson (@Astroguyz) <a href=””>August 9, 2021</a></blockquote><p>Generally, what will happen next based on previous observations of the star’s novae is that RS Ophiuchi, after a rapid burst into brightness, will gradually fade over the next few weeks, and eventually from view.</p><p>The <a href=””>maximum magnitude visible to the naked eye is about 6.5</a>, so you’ll want to get in quickly if you want to check it out – obviously binoculars or a telescope will improve the view.</p><p>The next outburst won’t take place until RS Ophiuchi has once again transferred sufficient hydrogen from the red giant to the white dwarf to trigger the thermonuclear explosion.</p><p>That won’t happen for another 15 to 20 years, probably (it does vary a little), so if you want to enjoy the light show, you should look towards the coordinates RA 17h 50m 13.17s, Dec –06° 42′ 28.6″.</p><p>Scientists will also likely be getting in on the action. Although several of the star’s eruptions have been observed, every nova affords new opportunities to learn more, since the technology to conduct observations will have improved since the last one.</p><p>Making a careful study of RS Ophiuchi with the current set of tools available to do so may very well yield new information about these fascinating explosive events.</p>
Wed, 11 Aug 2021 07:03:56 +0000 Michelle Starr

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