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In a dramatic, multi-staged eruption, the sun has revealed new clues that could help scientists solve the long-standing mystery of what causes the sun's powerful and unpredictable eruptions. Uncovering this fundamental physics could help scientists better predict the eruptions that cause dangerous space weather conditions at Earth. This explosion contained components of three different types of solar eruptions that usually occur separately—making it the first time such an event has been reported. Having all three eruption types together in one event provides scientists with something of a solar Rosetta Stone, allowing them to translate what they know about each type of solar eruption to understand other types and uncover an underlying mechanism that could explain all types of solar eruptions. "This event is a missing link, where we can see all of these aspects of different types of eruptions in one neat little package," said Emily Mason, lead author on the new study and solar scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland. "It drives home the point that these eruptions are caused by the same mechanism, just at different scales." Eruptions on the sun usually come in one of three forms: a coronal mass ejection, a jet, or a partial eruption. Coronal mass ejections—CMEs—and jets are both explosive eruptions that cast energy and particles into space, but they look very different. While jets erupt as narrow columns of solar material, CMEs form huge bubbles that expand out, pushed and sculpted by the sun's magnetic fields. Partial eruptions, on the other hand, start erupting from the surface but don't conjure enough energy to leave the sun, so most of the material falls back down onto the solar surface. An unusual eruption on the Sun may offer clues to understanding our star’s mysterious explosions. The new research studied an event named the “Rosetta Stone'' of solar eruptions. Just as the Rosetta Stone was the key to understanding Egyptian hieroglyphics, studying this eruption could be the key to understanding all types of solar eruptions. Credit: NASA/Mara Johnson-Groh/Haley Reed In this eruption—observed with NASA's Solar Dynamics Observatory and the European Space Agency and NASA's Solar and Heliospheric Observatory on March 12 and 13, 2016—the scientists saw the ejection of a hot layer of solar material above a magnetically active region on the sun's surface. The ejection was too big to be a jet, but too narrow to be a CME. Within a half an hour, a second cooler layer of material on the surface also started to erupt from the same place, but ultimately it fell back down as a partial eruption. Seeing an eruption with both jet and CME characteristics tells scientists they're likely caused by a singular mechanism. With this new understanding, scientists can apply what they know about jets to CMEs. The event also tells scientists that partial eruptions occur on the same spectrum but encounter some yet-unknown limiter that restricts their energy and doesn't allow them to make it off the sun. Understanding the mechanism behind these events, especially CMEs, is of critical importance to predicting when a large eruption might cause disruptions at Earth. CMEs in particular release large clouds of high-energy charged particles and magnetic fields that stream out across the solar system and can result in the space weather—a storm of high-energy particles and activity that can be dangerous to astronauts and technology in space and, in extreme cases, utility grids on Earth. By modeling the new Rosetta eruption and others since discovered like it, the scientists hope they can figure out what root mechanism causes solar eruptions and determines their characteristics. Finding a trigger could ultimately allow scientists to predict when a large eruption could threaten Earth and Mars several hours in advance—providing enough time for astronauts and spacecraft operators to take precautionary measures. The new study was presented on June 7, 2021, by Mason at the AAS 238 meeting and has been accepted for publication in Astrophysical Journal Letters. https://phys.org/news/2021-06-rosetta-stone-eruption-sun-solar.html
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We must also keep in mind several Countries have their own UFOs (secret) especially the USA, Russia, and China which may account for many sightings worldwide .. The US military has released previously classified photos and films related to unidentified flying object (UFO) sightings, which mostly show something blurry moving strangely. Still, I hear that a friend of a friend has gone from thinking there's a 1% chance that UFOs are aliens to now believing it is 50%. Is he rational? People are constantly seeing things in the sky they don't understand. The vast majority are airplanes, satellites, weather balloons, clouds, rocket launches, auroras, optical reflections and so on. But for some sightings, there's no known explanation. The problem is that people jump to the conclusion "unknown = aliens". And when you think about it, this is fairly odd. Why not angels? Anyway, I like to do maths instead. The Bayes formula (below), a mainstay of statistics, gives the probability (Pr) of something, given some evidence. Spelled out, it says that the probability that UFOs are aliens given some evidence is equal to how likely it is that the evidence would appear if UFOs really were aliens, times how likely it is that there are aliens. That needs to be divided by how likely the actual evidence is, which is notoriously difficult to work out. But what we are really interested in is if the evidence tells us we should believe in aliens compared to not believing in aliens. We can do this by dividing the equation above with the counterpart for UFOs not being aliens: When we do this, we also get rid of that pesky factor for how probable the evidence is. The equation now shows how likely it is that UFOs are aliens compared to how likely it is that they are not—after looking at the footage. The result will be one if the options are equally likely, and high if aliens are the stronger bet. It tells us how we should update our beliefs based on new evidence. There are two factors in the equation. One (second bracket) is how likely we think aliens are. Some might say 50:50, making this factor one, while others may make it very low, like 10-23. This is a statement of belief based on knowledge of the world (using for example the famous Drake equation). This needs to be multiplied by another factor (first bracket), often called the Bayes factor. It denotes how specific the evidence we see is for aliens v no aliens. If I meet a little green blob claiming to be from Epsilon Eridani, that is relatively specific (but could still somewhat be explained by a prank or me being mad). In this case, the factor may be much bigger than 1 and I get to shift towards thinking there are aliens. If I see a mysterious blob of light in the sky that could be aliens but could also be a lot of other things, then the factor would not be much different from 1—the evidence is as specific for aliens as it is for no aliens, and I don't get much change in belief. In other words, specificity is hugely important. Weird and unknown things may happen, but if the lights could equally well be faeries, intrusions from the fifth dimension, swamp gas, Chinese drones, sapient octopuses, or anything else, the Bayes factor will still be close to 1. That the world is strange is not evidence for aliens. My verdict https://phys.org/news/2021-06-ufos-odds-alien-spaceship.html
55 views · Jun 8th
Using the Hubble Space Telescope (HST), astronomers have conducted near-ultraviolet through near-infrared observations of a young planetary nebula (PN) known as NGC 6302. Results of the monitoring campaign, presented May 28 on arXiv.org, could help us better understand the nature of this PN. PNe are expanding shells of gas and dust that have been ejected from a star during the process of its evolution from a main sequence star into a red giant or white dwarf. They are relatively rare, but are important for astronomers studying the chemical evolution of stars and galaxies. Located some 3,400 light years away in the constellation Scorpius, NGC 6302 (also known as the Bug Nebula, Butterfly Nebula, or Caldwell 69) is a bi-lobed, pinched-waist PN rich in dust and molecular gas. Its relative proximity makes it a great target for high-resolution imaging aimed at understanding the origin and evolution of bipolar structures in the population of known PNe. Therefore, a group of astronomers led by Joel H. Kastner of the Rochester Institute of Technology (RIT) employed Hubble's Wide Field Camera 3 (WFC3) in order to obtain comprehensive, contemporaneous sets of near-UV through near-IR (243 nm to 1.6 µm) emission-line images of NGC 6302. "Here, we present the full suite of HST/WFC3 images of NGC 6302, along with various line ratio images and a detailed examination of the key results gleaned from these images thus far," the researchers wrote in the paper. Hubble images show that NGC 6302 has a dusty toroidal equatorial structure that bisects the PN's polar lobes, and fine structures (like clumps, knots, and filaments) within the lobes. Such morphology is highly unusual for bipolar PNe, apart from certain multipolar PNe. The study identified an unexpected bright, S-shaped 1.64 µm [Fe II] emission in NGC 6302 that traces the southern interior of the east lobe rim and the northern interior of the west lobe rim. The astronomers assume that this could be a zone of shocks caused by ongoing, fast, collimated winds from the PN's central star. Furthermore, the research found that the object previously identified as the central star of NGC 6302 is in fact a foreground field star. The scientists added that a pair of bubble-like features in the core region of NGC 6302 likely indicates the central star's actual position within the PN's dusty central torus. However, more subarcsecond-resolution observations in the mid-IR and submillimeter wavebands are required to confirm this. In concluding remarks, the authors of the paper noted that the results emphasize the mysterious nature of NGC 6302. "The features revealed by our panchromatic HST/WFC3 images of NGC 6302—in particular, its distinct azimuthal structural zones and nested bubble system, and the surprising misalignment of the central engine's present collimated fast wind direction (as traced by 1.64 µm [Fe II] emission) and the nebula's main axis of symmetry (as defined by its dusty molecular torus, polar-axis clump system, and outer lobe walls)—presents an especially daunting challenge for models of the origin and evolution of bipolar structures in PNe," the scientists concluded. https://phys.org/news/2021-06-astronomers-probe-planetary-nebula-ngc.html
49 views · Jun 8th
For the first time, a unique study conducted at Lund University in Sweden has tracked the meteorite flux to Earth over the past 500 million years. Contrary to current theories, researchers have determined that major collisions in the asteroid belt have not generally affected the number of impacts with Earth to any great extent. Researchers have been studying geological series since the 19th century in order to reconstruct how flora, fauna and the climate have changed over millions of years. Until now, however, almost nothing has been known about ancient meteorite flux—which makes sense since impact is rare, and the battered celestial bodies quickly break down as they encounter Earth's oxygen. A new study published in PNAS shows how researchers in Lund have reconstructed meteorite bombardment towards Earth over the past 500 million years. "The research community previously believed that meteorite flux to Earth was connected to dramatic events in the asteroid belt. The new study, however, shows that the flux has instead been very stable," says Birger Schmitz, professor of geology at Lund University. To conduct the study, researchers at Lund University's Astrogeobiology Laboratory dissolved almost ten tons of sedimentary rocks from ancient seabeds in strong acids because the sediment contains residue from the meteorites dating back to when they fell to Earth. Meteorites contain a small fraction of a mineral, a chromium oxide, which is very resistant to degradation. The microscopic chromium oxide grains were sifted out in the laboratory and serve as time capsules with an abundance of information. "The dissolved sediment represents 15 periods over the past 500 million years. In total, we have extracted chromium oxide from almost 10 000 different meteorites. Chemical analyses then enabled us to determine which types of meteorites the grains represent," says Birger Schmitz. A couple of thousand meteorites land on the Earth's surface every year, and approximately 63 000 space rocks have been documented by science. The space rocks originate from the asteroid belt between Mars and Jupiter where battered celestial bodies from gigantic collisions revolve around the sun. "We were very surprised to learn that only one of the 70 largest asteroid collisions that took place over the past 500 million years resulted in an increased flux of meteorites to Earth. For some reason, most of the rocks stay in the asteroid belt," says Birger Schmitz. The study not only upends generally accepted meteorite flux theories; it also provides entirely new perspectives on which types of celestial bodies are at greatest risk of colliding with Earth and where in the solar system they originate. From a geological time perspective, kilometer-sized celestial bodies collide with the Earth on a regular basis. One such event took place 66 million years ago, when a celestial body stretching over 10 kilometers in size hit the Yucatán Peninsula. The impact was part of the reason the Earth went dark and dinosaurs starved to death. "Future impact from even a small asteroid for example in the sea close to a populated area could lead to disastrous outcomes. This study provides important understanding that we can use to prevent this from happening; for example, by attempting to influence the trajectory of rapidly approaching celestial bodies," concludes Birger Schmitz. https://phys.org/news/2021-06-earth-meteorite-impacts-million-years.html
48 views · Jun 8th

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We must also keep in mind several Countries have their own UFOs (secret) especially the USA, Russia, and China which may account for many sightings worldwide .. The US military has released previously classified photos and films related to unidentified flying object (UFO) sightings, which mostly show something blurry moving strangely. Still, I hear that a friend of a friend has gone from thinking there's a 1% chance that UFOs are aliens to now believing it is 50%. Is he rational? People are constantly seeing things in the sky they don't understand. The vast majority are airplanes, satellites, weather balloons, clouds, rocket launches, auroras, optical reflections and so on. But for some sightings, there's no known explanation. The problem is that people jump to the conclusion "unknown = aliens". And when you think about it, this is fairly odd. Why not angels? Anyway, I like to do maths instead. The Bayes formula (below), a mainstay of statistics, gives the probability (Pr) of something, given some evidence. Spelled out, it says that the probability that UFOs are aliens given some evidence is equal to how likely it is that the evidence would appear if UFOs really were aliens, times how likely it is that there are aliens. That needs to be divided by how likely the actual evidence is, which is notoriously difficult to work out. But what we are really interested in is if the evidence tells us we should believe in aliens compared to not believing in aliens. We can do this by dividing the equation above with the counterpart for UFOs not being aliens: When we do this, we also get rid of that pesky factor for how probable the evidence is. The equation now shows how likely it is that UFOs are aliens compared to how likely it is that they are not—after looking at the footage. The result will be one if the options are equally likely, and high if aliens are the stronger bet. It tells us how we should update our beliefs based on new evidence. There are two factors in the equation. One (second bracket) is how likely we think aliens are. Some might say 50:50, making this factor one, while others may make it very low, like 10-23. This is a statement of belief based on knowledge of the world (using for example the famous Drake equation). This needs to be multiplied by another factor (first bracket), often called the Bayes factor. It denotes how specific the evidence we see is for aliens v no aliens. If I meet a little green blob claiming to be from Epsilon Eridani, that is relatively specific (but could still somewhat be explained by a prank or me being mad). In this case, the factor may be much bigger than 1 and I get to shift towards thinking there are aliens. If I see a mysterious blob of light in the sky that could be aliens but could also be a lot of other things, then the factor would not be much different from 1—the evidence is as specific for aliens as it is for no aliens, and I don't get much change in belief. In other words, specificity is hugely important. Weird and unknown things may happen, but if the lights could equally well be faeries, intrusions from the fifth dimension, swamp gas, Chinese drones, sapient octopuses, or anything else, the Bayes factor will still be close to 1. That the world is strange is not evidence for aliens. My verdict https://phys.org/news/2021-06-ufos-odds-alien-spaceship.html
55 views · Jun 8th
Using the Hubble Space Telescope (HST), astronomers have conducted near-ultraviolet through near-infrared observations of a young planetary nebula (PN) known as NGC 6302. Results of the monitoring campaign, presented May 28 on arXiv.org, could help us better understand the nature of this PN. PNe are expanding shells of gas and dust that have been ejected from a star during the process of its evolution from a main sequence star into a red giant or white dwarf. They are relatively rare, but are important for astronomers studying the chemical evolution of stars and galaxies. Located some 3,400 light years away in the constellation Scorpius, NGC 6302 (also known as the Bug Nebula, Butterfly Nebula, or Caldwell 69) is a bi-lobed, pinched-waist PN rich in dust and molecular gas. Its relative proximity makes it a great target for high-resolution imaging aimed at understanding the origin and evolution of bipolar structures in the population of known PNe. Therefore, a group of astronomers led by Joel H. Kastner of the Rochester Institute of Technology (RIT) employed Hubble's Wide Field Camera 3 (WFC3) in order to obtain comprehensive, contemporaneous sets of near-UV through near-IR (243 nm to 1.6 µm) emission-line images of NGC 6302. "Here, we present the full suite of HST/WFC3 images of NGC 6302, along with various line ratio images and a detailed examination of the key results gleaned from these images thus far," the researchers wrote in the paper. Hubble images show that NGC 6302 has a dusty toroidal equatorial structure that bisects the PN's polar lobes, and fine structures (like clumps, knots, and filaments) within the lobes. Such morphology is highly unusual for bipolar PNe, apart from certain multipolar PNe. The study identified an unexpected bright, S-shaped 1.64 µm [Fe II] emission in NGC 6302 that traces the southern interior of the east lobe rim and the northern interior of the west lobe rim. The astronomers assume that this could be a zone of shocks caused by ongoing, fast, collimated winds from the PN's central star. Furthermore, the research found that the object previously identified as the central star of NGC 6302 is in fact a foreground field star. The scientists added that a pair of bubble-like features in the core region of NGC 6302 likely indicates the central star's actual position within the PN's dusty central torus. However, more subarcsecond-resolution observations in the mid-IR and submillimeter wavebands are required to confirm this. In concluding remarks, the authors of the paper noted that the results emphasize the mysterious nature of NGC 6302. "The features revealed by our panchromatic HST/WFC3 images of NGC 6302—in particular, its distinct azimuthal structural zones and nested bubble system, and the surprising misalignment of the central engine's present collimated fast wind direction (as traced by 1.64 µm [Fe II] emission) and the nebula's main axis of symmetry (as defined by its dusty molecular torus, polar-axis clump system, and outer lobe walls)—presents an especially daunting challenge for models of the origin and evolution of bipolar structures in PNe," the scientists concluded. https://phys.org/news/2021-06-astronomers-probe-planetary-nebula-ngc.html
49 views · Jun 8th
For the first time, a unique study conducted at Lund University in Sweden has tracked the meteorite flux to Earth over the past 500 million years. Contrary to current theories, researchers have determined that major collisions in the asteroid belt have not generally affected the number of impacts with Earth to any great extent. Researchers have been studying geological series since the 19th century in order to reconstruct how flora, fauna and the climate have changed over millions of years. Until now, however, almost nothing has been known about ancient meteorite flux—which makes sense since impact is rare, and the battered celestial bodies quickly break down as they encounter Earth's oxygen. A new study published in PNAS shows how researchers in Lund have reconstructed meteorite bombardment towards Earth over the past 500 million years. "The research community previously believed that meteorite flux to Earth was connected to dramatic events in the asteroid belt. The new study, however, shows that the flux has instead been very stable," says Birger Schmitz, professor of geology at Lund University. To conduct the study, researchers at Lund University's Astrogeobiology Laboratory dissolved almost ten tons of sedimentary rocks from ancient seabeds in strong acids because the sediment contains residue from the meteorites dating back to when they fell to Earth. Meteorites contain a small fraction of a mineral, a chromium oxide, which is very resistant to degradation. The microscopic chromium oxide grains were sifted out in the laboratory and serve as time capsules with an abundance of information. "The dissolved sediment represents 15 periods over the past 500 million years. In total, we have extracted chromium oxide from almost 10 000 different meteorites. Chemical analyses then enabled us to determine which types of meteorites the grains represent," says Birger Schmitz. A couple of thousand meteorites land on the Earth's surface every year, and approximately 63 000 space rocks have been documented by science. The space rocks originate from the asteroid belt between Mars and Jupiter where battered celestial bodies from gigantic collisions revolve around the sun. "We were very surprised to learn that only one of the 70 largest asteroid collisions that took place over the past 500 million years resulted in an increased flux of meteorites to Earth. For some reason, most of the rocks stay in the asteroid belt," says Birger Schmitz. The study not only upends generally accepted meteorite flux theories; it also provides entirely new perspectives on which types of celestial bodies are at greatest risk of colliding with Earth and where in the solar system they originate. From a geological time perspective, kilometer-sized celestial bodies collide with the Earth on a regular basis. One such event took place 66 million years ago, when a celestial body stretching over 10 kilometers in size hit the Yucatán Peninsula. The impact was part of the reason the Earth went dark and dinosaurs starved to death. "Future impact from even a small asteroid for example in the sea close to a populated area could lead to disastrous outcomes. This study provides important understanding that we can use to prevent this from happening; for example, by attempting to influence the trajectory of rapidly approaching celestial bodies," concludes Birger Schmitz. https://phys.org/news/2021-06-earth-meteorite-impacts-million-years.html
48 views · Jun 8th