Tagged: Discover Magazine Toggle Comment Threads | Keyboard Shortcuts

  • richardmitnick 7:46 am on August 13, 2020 Permalink | Reply
    Tags: "Trying to Forecast Earthquakes Near the Salton Sea", , Discover Magazine, , , , ,   

    From Discover Magazine: “Trying to Forecast Earthquakes Near the Salton Sea” 

    DiscoverMag

    From Discover Magazine

    August 12, 2020
    Erik Klemetti

    1
    A view across the Salton Sea in California. Credit: Moonjazz / Flickr.

    No one can “predict” an earthquake. Let’s get that out first. We don’t understand enough of exactly what triggers large earthquakes to ever say with any certainty that one will strike on a specific day in a specific location. However, by looking at patterns of earthquakes in the past and swarms of earthquakes in the present, seismologists can begin to forecast the likelihood of a big earthquake. This is like weather forecasting — we know there is a chance of something happening, but by no means is it a prediction of something happening at a specific time and date.

    Southern California has been experiencing an earthquake swarm near the Salton Sea for the past few days. None of the earthquakes have been big. They have mostly been in the magnitude 2-3 range with a few as large as M4.6. The smaller ones you might notice, the larger would definitely be felt, but none are widely destructive. So, where could all these earthquakes lead?

    Busy Geology of the Salton Sea

    The Salton Sea lies along the San Andreas Fault System, although it is a somewhat complicated area. The Sea lies in the Brawley Seismic Zone, where there is both the classic side-by-side motion (strike-slip) of the San Andreas Fault as well as pull-apart motion (extension) that makes the basin. In fact, the Brawley Seismic Zone is the northernmost piece of the Pacific Ocean spreading that extends to the southern hemisphere. North of the Salton Sea, this spreading becomes the side-by-side sliding of North America and the Pacific Plate.

    This means that multiple kinds of earthquakes can happen and some of them can be large. This seismic zone has produced two major earthquakes over the past 100 years: the M6.9 El Centro temblor in 1940 and the M6.5 Imperial Valley earthquake in 1979. As recently as 2012, an earthquake swarm in the area produced earthquakes up to M5. That swarm may have been triggered by the geothermal injections done in that area.

    The Salton Sea area is also home to potentially active volcanoes. The Salton Buttes are rhyolite volcanoes that lie in and along the Sea and may have erupted as recently as about 200 AD. Now, these earthquake swarms in 2012 and now are not connected to magma moving under the area, but it just shows how geologically active this area is.

    Current Earthquake Swarm

    2
    The current earthquake swarm in California’s Salton Sea that started on August 10, 2020. Credit: USGS.

    The current earthquake swarm started on August 10 and has already generated dozens of earthquakes underneath the Salton Sea. These swarms aren’t uncommon – this is now the fourth of this century and they usually end in less than a month., However, this activity did prompt the US Geologic Survey to release a forecast for the potential of a large earthquake. After the first day, they forecasted an 80% chance of the swarm continuing but not producing any temblors larger than M5. This would be the typical behavior for swarms like this in the area.

    However, they did say there was a 19% chance of the earthquakes in the swarm being foreshocks of a potentially larger earthquake in line with what has happened during the past 100 years. That’s not a high probability, but enough to note.

    An even smaller chance exists for a truly massive earthquake larger than M7, but that was only about a 1% chance. That’s because they occur much less frequently in that stretch of southern California. Unlike the M6 earthquakes that have happened multiple times in the past century, a M7 earthquake hasn’t happened in 300 years.

    The swarm has settled down a bit since its opening day, so the USGS has revised its initial estimates. Now they think that it is a 98% chance that the swarm continues much as it is going now and has dropped the chance of a large earthquake down to 2% (and very large to <1%).

    This is no guarantee, but with new data comes a new forecast. Think of this like trying to forecast how strong a hurricane might be when it makes landfall — new information about the winds and barometric pressure lead to a new forecast. For earthquakes, the changing frequency and size of the swarm might hint at new probabilities.

    We're still in the infancy of earthquake forecasting. The most important thing you can take away from all this is that if you live in one of these areas, you should always be prepared for the next big earthquakes. Earthquakes can happen almost anywhere in the country — just look at Sunday's M5.1 in North Carolina — but we can be prepared for their impact.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 2:02 pm on July 16, 2020 Permalink | Reply
    Tags: "Powerful Eruptions On The Sun Might Trigger Earthquakes", , Discover Magazine, , ESA/NASA SOHO which is located 900000 miles (1.45 million kilometers) from Earth keeps its sights set on the sun which helps scientists track how much solar material ends up striking our planet., Ground-shaking earthquakes occur all across the globe. And according to a new study many of them might be triggered by the sun., Reverse piezoelectric effect ?, Scientists have learned that large powerful earthquakes commonly occur in groups not in random patterns.   

    From Discover Magazine: “Powerful Eruptions On The Sun Might Trigger Earthquakes” 

    DiscoverMag

    From Discover Magazine

    July 14, 2020
    Mara Johnson-Groh

    Ground-shaking earthquakes occur all across the globe. And according to a new study, many of them might be triggered by the sun.

    1
    This false-color composite of the Sun was created using ultraviolet images taken by the Solar and Heliospheric Observatory (SOHO) satellite. (Credit: NASA/ESA)

    ESA/NASA SOHO

    Through decades of research, scientists have learned that large, powerful earthquakes commonly occur in groups, not in random patterns. But exactly why has so far remained a mystery. Now, new research published July 13 in Scientific Reports, asserts the first strong — though still disputed — evidence that powerful eruptions on the sun can trigger mass earthquake events on Earth.

    “Large earthquakes all around the world are not evenly distributed … there is some correlation among them,” says Giuseppe De Natale, research director at the National Institute of Geophysics and Volcanology in Rome and co-author of the new study. “We have tested the hypothesis that solar activity can influence the worldwide [occurrence of earthquakes].”

    A Solar Origin for Earthquakes

    To the unaided eye, the sun might seem relatively docile. But our star is constantly bombarding the solar system with vast amounts of energy and particles in the form of the solar wind. Sometimes, however, formidable eruptions on the sun’s surface cause coronal mass ejections, or especially energetic floods of particles — including ions and electrons — that careen through the solar system at breakneck speeds. When they reach Earth, these charged particles can interfere with satellites, and under extreme circumstances, take down power grids. The new research suggests that particles from powerful eruptions like this — specifically, the positively charged ions — might be responsible for triggering groups of strong earthquakes.

    Earthquakes typically occur when rocks grind past one another as Earth’s tectonic plates shift and jostle for position. When the intense friction that’s locking plates together is overcome, the rocks break, releasing tremendous amounts of energy and shaking the ground.

    But scientists have also noticed a pattern in some large earthquakes around the planet: they tend to occur in groups, not at random. This suggests there may be some global phenomenon that’s triggering these worldwide earthquake parties. And though many researchers have done statistical studies to try to determine a cause before, no compelling theories have yet been rigorously proven.

    So, to tackle the lingering mystery, the researchers of this latest study combed through 20 years of data on both earthquakes and solar activity, searching for any possible correlations. Specifically, the team used data from NASA-ESA’s Solar and Heliospheric Observatory (SOHO) satellite [above], compiling measurements of protons (positively charged particles) that come from the sun and wash over our planet.

    3
    Central and South American earthquakes, shown as dots in this image, are documented as part of the ISC-GEM Global Instrumental Earthquake Catalogue project. (Credit: International Seismological Centre)

    SOHO, which is located 900,000 miles (1.45 million kilometers) from Earth, keeps its sights set on the sun, which helps scientists track how much solar material ends up striking our planet. By comparing the ISC-GEM Global Instrumental Earthquake Catalogue — a historical record of strong earthquakes — to SOHO data, the scientists noticed more strong earthquakes occurred when the number and velocities of incoming solar protons increased. Specifically, when protons streaming from the sun peaked, there was a spike in quakes above magnitude 5.6 for the next 24 hours.

    “This statistical test of the hypothesis is very significant,” De Natale says. “The probability that it’s just by chance that we observe this, is very, very low — less than 1 in 100,000.”

    A Piezoelectrical Origin for Earthquakes

    After noticing the correlation between solar proton flux and strong earthquakes, the researchers went on to propose a possible explanation: a mechanism called the reverse piezoelectric effect.

    Previous experiments have clearly shown that compressing quartz, a rock common in the Earth’s crust, can generate an electrical pulse through a process known as the piezoelectric effect. The researchers think that such small pulses could destabilize faults that are already close to rupturing, triggering earthquakes. In fact, signatures from electromagnetic events — such as earthquake lightning and radio waves — have been recorded occurring alongside earthquakes in the past. Some researchers think these events are caused by the earthquakes themselves. But several other studies have detected strong electromagnetic anomalies before large earthquakes, not after, so the exact nature of the relationship between earthquakes and electromagnetic events is still debated.

    The new explanation, however, flips this electromagnetic cause-and-effect on its head, suggesting electromagnetic anomalies aren’t the result of earthquakes, but instead cause them. It goes like this: As positively charged protons from the sun crash into Earth protective magnetic bubble, they create electromagnetic currents that propagate across the globe. Pulses created by these currents could then go on to deform quartz in Earth’s crust, ultimately triggering quakes.

    This is not the first time scientists have tried to link solar activity to earthquakes, however. In 1853, a Swiss astronomer named Rudolf Wolf tried to connect sunspots ­— locations of intense magnetic activity on the surface of the sun — to earthquakes. More recent experiments have also sought such a link, but strong statistical evidence remains out of reach. A 2013 paper published in Geophysical Review Letters, for instance, looked at 100 years of sunspot and geomagnetic data, finding no evidence of a connection between the sun and earthquakes.

    Partly because long-term efforts to find a link between the sun and earthquakes have come up short, this latest claim that solar protons may play a role has been met by notable skepticism in the research community. Some are wary of the statistical analysis performed on the data, while others take issue with how the data was selected.

    “The results [from the new paper] alone don’t tell you there’s actually any real physical connection, I think,” says Jeremy Thomas, a research scientist at NorthWest Research Associates who was not involved in the new research. “There could be, but I don’t think it’s proving that.”

    As is almost always the case with science, more research is required before we can know for sure if the sun can trigger earthquakes. But if future work manages to cement the proposed connection, keeping a close eye on our shining star might help us better predict and prepare for when the ground unexpectedly and violently shakes beneath our feet, possibly helping save lives.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 12:55 pm on July 3, 2020 Permalink | Reply
    Tags: "Thorne-Żytkow Objects: When a Supergiant Star Swallows a Dead Star", , , , Both theory and observation still have a long way to go., , Discover Magazine, HV 2112, HV 2112: A Strange Star Disputed, Thorne-Żytkow Object Discovered in 2014   

    From Discover Magazine: “Thorne-Żytkow Objects: When a Supergiant Star Swallows a Dead Star” 

    DiscoverMag

    From Discover Magazine

    July 3, 2020
    Eric Betz

    One of the universe’s strangest stars is thought to form when a neutron star gets sucked into a red supergiant. But despite 45 years of searching, astronomers still aren’t sure they’ve ever found one.

    1
    A Thorne-Żytkow object is a theoretical type of hybrid star created when a dense neutron star is swallowed by a puffy red supergiant star, as seen in this artist’s concept. (Credit: Astronomy Magazine)

    Nearly half a century ago, physicist Kip Thorne (now a Nobel laureate) and astronomer Anna Żytkow suggested a strange, Russian-nesting-doll-type star might be hiding in the cosmos, just waiting to be found by those who knew how to seek it. Astronomers named these theoretical stellar hybrids Thorne-Żytkow objects.

    The possible existence of Thorne-Żytkow objects came to light when their namesake researchers ran early computer simulations. When they did, they found that a neutron star — a tiny, ultra-dense stellar remnant left behind when a star goes supernova — could be gobbled up by a red supergiant star.

    According to the simulations, if the “Twins” (in the Danny DeVito-Arnold Schwarzenegger sense) get too close to one another, instead of one star getting ejected, the two stars can merge together. The city-sized, solar-mass neutron star would carry on living inside its much larger host, almost like a cosmic parasite.

    But even if physics really allows for such stars to exist, finding them will be hard.

    In a study published in 1975 in The Astrophysical Journal, Thorne and Żytkow suggested these stars would look almost identical to red supergiants like Betelgeuse in the constellation Orion. Supergiant stars are relatively common and are some of the youngest and largest stars in the universe. Thorne-Żytkow objects (TZOs) would look very similar to red supergiants, but are suspected to survive up to 10 times longer.

    Ordinary red supergiants, like other stars, are powered by nuclear fusion in their cores. So when that energy runs out, their uncontested gravity causes them to implode before erupting as a supernova. But TZOs can live such long lives because they do not rely on sustained nuclear fusion in their cores to avoid collapse. Instead, a TZO’s neutron star core, which is already extremely compressed, largely prevents the rapid and uncontested gravitational collapse of the surrounding supergiant layers.

    Astronomers have two different theories for how TZOs form — and they both depend on the initial objects starting their lives as two gigantic stars in a close binary system. In one theory, the bigger of the two stars would explode as a supernova first, leaving behind a neutron star. But over time, the remaining supergiant would continue to balloon outward, growing until it fully swallowed the nearby neutron star remnant.

    Another possibility for the formation of TZOs is that when one star explodes as an asymmetric supernova, its remnant core could get a powerful “kick.” That could potentially fire the neutron star into the belly of the remaining red giant.

    2
    A candidate Thorne-Zytkow object (yellow box) shines among the stars of the Small Magellanic Cloud. (Credit: ESA/Hubble)

    Thorne-Żytkow Object Discovered

    But no matter how they form, astronomers in 2014 announced they may have discovered the first Thorne-Żytkow object. The star was hiding some 200,000 light-years away in the Small Magellanic Cloud, a dwarf galaxy that orbits the Milky Way.

    smc

    Small Magellanic Cloud. 10 November 2005. NASA/ESA Hubble and Digitized Sky Survey 2

    It was found by astronomer Emily Levesque, now at the University of Washington, with the help of her team of researchers. To find the suspected TZO, Levesque’s group used New Mexico’s Apache Point Observatory to study two dozen red supergiant stars in the Milky Way, as well as one of the Magellan Telescopes in Chile to study another group of supergiants in the Small Magellanic Cloud.

    Apache Point Observatory, near Sunspot, New Mexico Altitude 2,788 meters (9,147 ft)

    Carnegie 6.5 meter Magellan Baade and Clay Telescopes located at Carnegie’s Las Campanas Observatory, Chile. over 2,500 m (8,200 ft) high

    Upon reviewing the data, one star in particular stood out. The system, dubbed HV 2112, was initially cataloged as variable in 1908 by pioneering astronomer Henrietta Swan Leavitt. At the time, though, astronomers thought it was a red supergiant living out its dying days before going supernova.

    However, more than 100 years after Leavitt first noted the strange object, Levesque and her team’s analysis revealed unusual chemical signatures that they thought could be the tell-tale signs of a mythical Thorne-Żytkow object. The researchers saw excess amounts of lithium, calcium and other elements, which they could only explain through the unique nuclear reactions that would occur inside a TZO.

    But they couldn’t be completely sure; HV 2112 also seemed to have other strange chemical fingerprints that they didn’t expect to see. Based on these remaining mysteries, the team suggests that either theoretical models haven’t fully appreciated the nuances of Thorne-Żytkow objects, or HV 2112 simply wasn’t a TZO in the first place.

    HV 2112: A Strange Star Disputed

    The bizarre nature of the find sparked headlines at the time. But for astronomers, it was also an important discovery because it offered evidence for stars powered by processes beyond nuclear fusion.

    But four years later, in 2018, another group of astronomers pushed “pause” on this unique find [MNRAS]. They’d done their own analysis of HV 2112 and compared it to similar stars, but didn’t find the same levels of excess calcium or other elements spotted by Levesque’s team. The new analysis did show a surplus of lithium, but, other than that, the results suggested this star was basically an ordinary red supergiant.

    Though the team might have dashed HV 2112’s dreams of being different, they did offer up the hope a replacement candidate. They found another possible Thorne-Żytkow object, cataloged as HV 11417, which did sport some of tell-tale signs that astronomers predicted the objects should have.

    One thing the two teams do agree on is that when it comes to Thorne-Żytkow objects, both theory and observation still have a long way to go.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 2:15 pm on June 22, 2020 Permalink | Reply
    Tags: "How Many Extraterrestrial Civilizations Can Communicate In Our Galaxy Right Now? (Spoiler: It's More Than One)", Discover Magazine, ,   

    From Discover Magazine: “How Many Extraterrestrial Civilizations Can Communicate In Our Galaxy Right Now? (Spoiler: It’s More Than One)” 

    DiscoverMag

    From Discover Magazine

    A new way to count the number of intelligent ET cultures suggests we are far from alone; but also that we may never be able to find them, astronomers say.

    June 22, 2020

    1
    (Credit: sdecoret/Shutterstock)

    The Copernican principle is the idea that Earth does not sit at the center of universe or is otherwise special in any way. When Nicolaus Copernicus first stated it in the 16th century, it led to an entirely new way to think about our planet.

    Since then, scientists have applied the principle more broadly to suggest that humans have no special privileged view of the universe. We are just ordinary observers sitting on an ordinary planet in an ordinary part of an ordinary galaxy.

    This form of thinking has had profound consequences. It led Copernicus to the idea that Earth orbits the sun and Einstein to his general theory of relativity. And it regularly guides the thinking of physicists, astronomers and cosmologists about the nature of the universe.

    Now, Tom Westby and Christopher Conselice at the University of Nottingham in the U.K. have used the Copernican principle to come up with a new take on the existence of extraterrestrial civilizations. They point out that the principle implies there is nothing special about the conditions on Earth that allowed intelligent life to evolve. So, wherever these conditions exist, intelligent life is likely to evolve over about the same timescale as it evolved here.

    This “astrobiological Copernican principle” has important implications for the way astronomers estimate the number of extraterrestrial civilizations that might be capable of communicating with us. Indeed, Westby and Conselice have crunched the numbers and say that, given the strongest limits they can place on the numbers, there are probably about 36 civilizations in the galaxy right now with this capability. But the numbers come with a significant caveat that also throws light on the Fermi Paradox, which famously suggests that if intelligent aliens exist, surely we ought to have seen them by now.

    First, some background. Back in 1961, the American astrophysicist Frank Drake wrote down an equation of endless fascination that estimates the number of communicating extraterrestrial civilizations in our galaxy.

    Drake Equation

    Frank Drake with his Drake Equation. Credit Frank Drake


    Drake Equation, Frank Drake, Seti Institute

    The Drake Equation starts with an estimate of the number of stars in the galaxy, then calculates the fraction that have planets in the habitable zone. It then estimates the fraction on which life develops and then those on which life becomes intelligent and capable of communicating.

    The final term is the length of time over which this civilization broadcasts signals that we might be able to detect. The result is the number of civilizations that we might be capable of communicating with today.

    Over the years, astrophysicists have reinterpreted these numbers in numerous ways, revising their estimates as new ideas and observational data change the estimates. And, in the last few years, a great deal of new observational data have emerged that have the potential to firm up some of the numbers.

    In particular, astronomers have confirmed the existence of exoplanets and begun to understand just how common they are in habitable zones throughout the galaxy. That provides some hard numbers to enter into the Drake Equation. Westby and Conselice have duly updated the equation with the latest figures.

    But they have also gone significantly further using the astrobiological Copernican principle. This is the idea that if a planet sits in the habitable zone of a system that is rich in the heavier elements necessary for life, then intelligent life will emerge on the timescale of between 4.5 billion and 5.5 billion years.

    The rationale is that intelligent life emerged over 5 billion years on Earth, and there is nothing special about our corner of the universe. Therefore, the same thing will happen over the same timescale in other similar corners.

    Nevertheless, this is a much stricter assumption than imagining life can emerge at any time after a planet is 5 billion years old (many stars are 10 billion years old). That’s why the researchers call this the Strong Condition.

    When the astronomers enter these numbers into the Drake Equation, the number of civilizations is huge. But there is another limiting factor — the length of time over which these civilizations communicate — whether centuries, millennia or even longer. Obviously, the longer they are able to communicate, the more likely we are to overlap with them.

    However, Westby and Conselice decide on a figure of just 100 years. “We know that our own civilization has had radio communications for this time,” they say. So this is the lower limit on which they base their calculations.

    And the results make for interesting reading. “In the Strong Condition, we find there should be at least 36 civilizations within our galaxy,” say Westby and Conselice, although the number could be as many as 211 and as few as four.

    That may seem like a significant number, but the galaxy is large place. If spread uniformly throughout the galaxy, these civilizations would be a huge distance apart, say the researchers. “The nearest would be at a maximum distance given by 17,000 light-years, making communication or even detection of these systems nearly impossible with present technology,” they say.

    Fermi Paradox

    That provides an immediate rejoinder to the Fermi Paradox, which is sometimes used to suggest that we must be alone in the universe. It’s not that there aren’t any intelligent civilizations out there, it’s that they are distributed so thinly throughout the galaxy that we cannot spot them.

    As Douglas Adams has famously pointed out: Space is big. And the amount we have searched for signs of intelligent life is a tiny fraction. Westby and Conselice point to calculations suggesting the volume searched is equivalent to just 7,700 liters of Earth’s oceans.

    Of course, the researchers are well aware of the limitations of their argument. They acknowledge the well-known warning against drawing any inferences from a sample of just one. But that doesn’t stop them from speculating.

    The researchers also come to some other interesting conclusions. They point out that if they assume that primitive life arises wherever conditions are suitable for long enough, then the universe should be teeming with it. “Such generous assumptions lead to estimated numbers of habitats for primitive life in the Milky Way which reach into the tens of billions,” they say.

    The only question now is how long till we spot evidence of it.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 10:55 am on May 21, 2020 Permalink | Reply
    Tags: "There’s a Russian Volcano That Erupts Diamonds", , Discover Magazine, , Tolbachik volcano on the Kamchatka Peninsula in Russia   

    From Discover Magazine: “There’s a Russian Volcano That Erupts Diamonds” 

    DiscoverMag

    From Discover Magazine

    May 12, 2020
    Erik Klemetti

    Researchers looking at the 2012-13 eruption from Russia’s Tolbachik found tiny diamonds, but where are they from?

    1
    Tolbachik in Russia, with the cones from the 2012-13 eruption in the middle foreground. (Credit: kuhnmi/Flickr)

    Diamonds are remarkable. Most form deep within Earth, 62 miles or more beneath our feet and are brought to the surface in powerful explosive eruptions. Yet researchers looking at the 2012-13 eruption of Tolbachik on the Kamchatka Peninsula in Russia found tiny diamonds in the volcanic debris. This was not one of those powerful explosions but a massive series of lava flows. So why were there diamonds showing up unexpectedly?

    Diamonds from the Deep

    The “easiest” way to form diamonds is taking carbon and exposing it to the immense pressure within Earth’s mantle. Then they get coughed up with other chunks of rock from the mantle in these giant explosive eruptions called kimberlites. They’re named after one of the world’s most famous and productive diamond mines in Kimberley, South Africa. The places where we find most diamonds today are from the rocks created by these eruptions, found in places like northern Canada and Arkansas. Sometimes, glaciers or rivers have moved the diamonds from their sources, but they can be traced back to their original volcano sources.

    There hasn’t a kimberlite eruption in recent human history. The most recent known kimberlite eruption might have happened 10,000 to 20,000 years ago in Tanzania, and that is controversial. The last confirmed kimberlite erupted 30 million years ago in the Democratic Republic of the Congo. Both of those places (and the locations of most kimberlite eruptions) are old continental areas called “cratons,” away from active tectonic zones like volcanic arcs.

    So, what are diamonds doing in Kamchatka? The easternmost peninsula in Russia is a subduction zone, where the Pacific plate is sliding under Eurasia. There is a string of active volcanoes starting in Japan and running north into Kamchatka. In Russia, these include highly active volcanoes like Sheveluch, Klyuchevskoi and Bezymianny. So, not really the types of places we would normally expect to find those eruptions that bring diamonds up from the mantle.

    Yet, Erik Galimov and his colleagues found just that at Tolbachik. This Russian volcano produced one of the largest lava flow eruptions of the 21st century (so far), dumping over 1/10 of a cubic mile of lava. There were some explosions as part of the eruption, producing lava fountains that reached hundreds of meters upwards.

    From Russia, With Carbon

    A recent paper by Galimov and others in American Mineralogist details the tiny diamonds they found in lavas from Tolbachik. These crystals are less an a 0.03 inches and mostly found in the rocks made during the lava fountain phase of the eruption. So, how did these mysterious diamonds form?

    Normally, diamonds would be part of a foreign rock brought up in a kimberlite eruption. Geologists call these xenoliths, and the diamonds themselves are xenocrysts. They aren’t really related to the magma erupting, but they came along for the ride. However, these Tolbachik diamonds don’t seem to be from xenoliths because there isn’t much other evidence for these chunks of foreign debris in 2012-13 lava.

    2
    Microdiamonds found in lava from the 2012-13 eruption at Tolbachik. “Mkm” scale is micrometer (0.00003 inch). (Credit: Galimov et al. 2020 American Mineralogist)

    If they didn’t come from deep in the mantle, what are their sources? Galimov and others decided to look at the composition of the diamonds. Surprisingly enough, the composition of impurities in the diamonds in elements like nitrogen, fluorine, chlorine and silicon matched the composition of the volcanic gases from Tolbachik. This suggested that they may actually have been forming from the gases being released during the eruption.

    However, there was one more potential source for these diamonds: people! Could the microdiamonds actually just be contamination from drilling or the sampling instruments themselves? Most diamonds used in industry are synthetic and would have a specific nitrogen isotopic composition. Galimov and others looked at the nitrogen isotope composition of the Tolbachik diamonds and, sure enough, they weren’t synthetic. These diamonds formed naturally from the volcanic gases being released from the lava. [Author’s note: I’ve had a brief discussion with Dr. Ryan Ickert (Purdue University) and it seems like it might not be as simple at the paper portrays. It doesn’t change the idea that these diamonds are likely crystallized from the volcanic gases at Tolbachik, but the isotope argument might be messier.]

    This type of crystallization, directly from a gas, isn’t a new observation. In some rhyolite eruptions, the hot gases that get released after a massive explosive eruption form minerals like topaz. These diamonds at Tolbachik likely formed the same way, where hot volcanic gases laden in carbon dioxide and other elements cooled in bubbles and rapidly crystallized minerals like diamonds.

    Now, don’t rush out to Kamchatka. You’re not going to get rich from these tiny diamonds from Tolbachik. However, these little crystals show just how bizarre volcanic activity can be, where diamonds can form directly from a gas, high pressure not needed.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 6:25 pm on January 23, 2020 Permalink | Reply
    Tags: "Astronomers Find a New Explanation for a Super-Bright Supernova", , , , , Discover Magazine, Finding so much iron means the star that exploded was a white dwarf and not a large massive star that collapsed explosively., Finding the gassy material must have been released outward only 100 years or so before the supernova explosion — barely any time at all on astronomical scales., It was the brightest superluminous supernova they’d ever seen., or the two phenomena are somehow linked., , The team found that the stellar explosion must have contained iron — and a lot of it.   

    From Discover Magazine: “Astronomers Find a New Explanation for a Super-Bright Supernova” 

    DiscoverMag

    From Discover Magazine

    January 23, 2020
    Erika K. Carlson

    1
    The supernova SN 2006gy, shown in this illustration, was the brightest supernova discovered yet when it was spotted in 2006. (Credit: NASA/CXC/M.Weiss)

    Many stars end their lives as bright explosions called supernovas. Some of these explosions are much brighter than typical and give off up to 100 times more energy. Astronomers call these “superluminous supernovas,” and they don’t yet understand exactly what makes them super-bright.

    Now, a team of researchers has proposed an origin story for one of these superluminous supernovas, SN 2006gy. They suggest that the explosion happened in a binary star system when a small, dense white dwarf star spiraled into the core of its giant star companion.

    The researchers presented their findings in a new paper published Jan. 23 in Science.

    A Strange Explosion

    When astronomers spotted SN 2006gy in 2006, it was the brightest superluminous supernova they’d ever seen.

    Later, a group of researchers led by Koji Kawabata, now at Hiroshima University in Japan, managed to capture a detailed picture of the light that the supernova was emitting at various wavelengths, or colors. They saw that SN 2006gy was emitting light in combinations of wavelengths that hadn’t been seen in supernovas before.

    “It was kind of a very exciting mystery,” said Anders Jerkstrand, an astronomer at Stockholm University. He teamed up with Kawabata and another researcher to figure out what was going on and write the new paper.

    2
    The supernova SN 2006gy. (Credit: Fox et al 2015)

    A New Explanation

    By modeling what elements could have produced the wavelengths of light that SN 2006gy emitted, the team found that the stellar explosion must have contained iron — and a lot of it. Finding so much iron means the star that exploded was a white dwarf and not a large, massive star that collapsed explosively.

    The wavelengths SN 2006gy emitted also showed that the explosion must have rammed into and interacted with a slower-moving shell of gassy material around it, as other astronomers had previously pointed out. The collision with the surrounding material likely caused the explosion to convert a lot of its energy into light and produce such a bright supernova, Jerkstrand said.

    But the team found that the gassy material must have been released outward only 100 years or so before the supernova explosion — barely any time at all, on astronomical scales. Either it’s a coincidence that the shell of gases was ejected just before the supernova explosion, or the two phenomena are somehow linked.

    So the team came up with a scenario to explain both events. A dense white dwarf and a giant star with a stretched-out gassy atmosphere orbit each other in a binary system. The two stars are close enough that the white dwarf orbits inside the giant star’s gaseous outer layers. The resulting drag sends the white dwarf spiraling in toward the larger star’s core and also pushes gassy material outward.

    If the white dwarf colliding into the larger star’s core caused the supernova, the explosion would interact with the ejected gas on its way out, as astronomers observed. But the team can’t yet say that this is the case with SN 2006gy, because they don’t know for sure that the inspiraling would lead to the white dwarf’s explosion.

    “What we are saying is that if that happens, you get a supernova that looks just like 2006gy,” Jerkstrand said.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 11:20 am on January 16, 2020 Permalink | Reply
    Tags: "Why is Puerto Rico Being Struck by Earthquakes?", , Discover Magazine, ,   

    From Discover Magazine: “Why is Puerto Rico Being Struck by Earthquakes?” 

    DiscoverMag

    From Discover Magazine

    January 7, 2020
    Erik Klemetti

    Multiple large earthquakes have hit Puerto Rico over the past week, all thanks to the geologically-active Caribbean Plate.

    The tectonic plates of the world were mapped in 1996, USGS.

    1
    Map of recent earthquakes from late December into early January 2020 near Puerto Rico. Credit: USGS.

    Since Monday, Puerto Rico has been struck by multiple magnitude 5 and 6 earthquakes. These earthquakes caused significant damage on an island still recovering from the devastation of Hurricane Maria in 2017.

    Most people don’t think of the Caribbean as an area rife for geologic activity, but earthquakes and eruptions are common. The major earthquakes in Puerto Rico and Haiti, as well as eruptions on Montserrat are all reminders that complex interactions between tectonic plates lie along the Caribbean Ocean’s margins.

    The Caribbean plate lies beneath much of the ocean of the same name (see below). It is bounded in the north and east by the North American plate, to the south by the South American plate and to the west by the Cocos plate. There isn’t much land mass above sea level on the plate beyond the islands that stretch from southern Cuba to the Lesser Antilles, along with parts of Central America like Costa Rica and Panama. A few small platelets have been identified along the margins of the plate as well.

    2
    Tectonic plates in the eastern Caribbean with historical earthquakes from 1900-2016 marked. Source: USGS.

    The northern edge of the plate is a transform boundary, where the two plates are sliding by each other. This causes stress that leads to earthquakes, much the same as the earthquakes generated along the San Andreas fault in California. This is why we’ve seen large earthquakes in places like Haiti, the Dominican Republic and now Puerto Rico.

    Head to the east and you reach the curving arc of islands that form the Lesser Antilles. Many of these islands are homes to potentially active volcanoes, such as Soufrière Hills on Montserrat, Pelée on Martinique, La Soufrière on St. Vincent and more. Other islands are homes to relict volcanoes as well. All these volcanoes have been formed by the North American plate sliding underneath the Caribbean, similar to the Cascade Range in the western United States and Canada.

    So, Puerto Rico doesn’t have active volcanoes, but it can experience large earthquakes. One of the most famous in the 1918 San Fermín earthquake that was a magnitude 7.1. Unlike the current temblors, the San Fermín earthquake occurred north of the island under the sea, generating a tsunami. More than 100 people likely died in that event.

    The current spate of earthquakes struck near the southern coast of the island. Both of the largest earthquakes — Monday’s M5.8 and Tuesday’s M6.4 — occurred during the early morning hours, when most people are at home. This heightens the risk of injuries and fatalities if homes collapse, but luckily so far the number of deaths is low. However, there has been significant damage to home and infrastructure already made precarious by the devastation of Hurricane Maria. This means longer-term hazards for the people of Puerto Rico.

    On top of this, the earthquakes have triggered landslides and rockfalls, increasing the threat to the island’s residents. The shaking also destroyed a picturesque natural bridge on the coast of the island. With dozens of aftershocks so far, it may be quite some time before people feel secure again.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 12:38 pm on January 11, 2020 Permalink | Reply
    Tags: "Crater From Giant Meteorite Strike Might Be Hidden Under Volcanic Plateau", Although the evidence they present is thorough it’s not quite rock-solid., , Discover Magazine, Earth Observatory of Singapore, , New York Times, PNAS, , The first clue to the meteorite’s impact site came from the bits of glassy debris called tektites that it launched into the air about 800000 years ago., Ultimately a lava field in southern Laos turned up promising results.,   

    From smithsonian.com: “Crater From Giant Meteorite Strike Might Be Hidden Under Volcanic Plateau” 

    smithsonian
    From smithsonian.com

    January 10, 2020
    Theresa Machemer

    1
    A large meteorite can launch bits of molten rock into the atmosphere when it impacts Earth. When that molten rock cools, it forms tektites, shown here. (Photo by Robert Eastman / Alamy Stock Photo)

    Debris from the strike scattered across Earth, but the exact point of impact has been a mystery.

    The impact of a meteorite ranges from an Alabama woman’s giant bruise to the end of the dinosaurs. But one meteorite’s crater has eluded scientists for almost a century, despite the fact that it scattered glass confetti across one-tenth of the Earth’s surface. Now, experts at the Earth Observatory of Singapore have released a study, published in the Proceedings of the National Academy of Sciences, providing new evidence for the crater’s location.

    The first clue to the meteorite’s impact site came from the bits of glassy debris, called tektites, that it launched into the air about 800,000 years ago. The tektites landed across Antarctica, Australia and Asia, so geologist Kerry Sieh searched for signs of the crater in satellite imagery. Sieh’s search has taken years and led him down many dead-ends, Katherine Kornei reports for the New York Times-Hints of Phantom Crater Found Under Volcanic Plateau in Laos, but ultimately a lava field in southern Laos turned up promising results. There, volcanic eruptions long ago covered the land in molten rock, building a layer of igneous rock up to 1,000 feet deep, which could have easily obscured the impact crater.

    The research team began by analyzing previously published chemical characteristics of tektites found in Australia and Asia, and found evidence linking them to the Laotian lava field. They then estimated the age of the tektites and lava flows—the lava at the suspect site was younger than the lava around it—and measured the local gravitational field of the lava bed. Craters are often filled with less dense material that was broken apart on impact, and Sieh’s findings of a weaker gravitational pull provide more evidence of the impact crater’s existence.

    “There have been many, many attempts to find the impact site,” Sieh tells CNN’s Michelle Lim [A huge meteorite smashed into Earth nearly 800,000 years ago. We may have finally found the crater]. “But our study is the first to put together so many lines of evidence, ranging from the chemical nature of the tektites to their physical characteristics, and from gravity measurements to measurements of the age of lavas that could bury the crater.”

    By the new study’s calculations, the meteorite was about 1.2 miles wide and created a crater 8 miles wide and 11 miles long. It would have struck our planet at a speed fast enough to melt the Earth beneath it, material that was thrown into the air to create tektites. The impact also would have sent boulders flying at 1,500 feet per second, Leslie Nemo writes for Discover [Found: Crater From Asteroid Impact That Covered 10% of Earth’s Surface in Debris], some of which Sieh spotted in a hill that was cut through by a road a few miles away from the suspected impact site.

    Although the evidence they present is thorough, it’s not quite rock-solid. In a commentary [PNAS] that accompanied the study, impact crater expert Henry Melosh writes that Sieh and his team “present the best candidate yet for the long-sought source crater,” but adds, “one of my impact-savvy colleagues read the paper and was unconvinced. As with all possible impact craters, proof will rest on finding shock-metamorphosed rocks, minerals, and melt.”

    Melosh points out that the crater is smaller than previously expected for this meteorite, and that it would have had to land at an unusually shallow angle to create the oval shape that Sieh’s team proposes. To provide the strongest evidence that this is the crater they’ve been looking for, scientists would have to drill through the lava flows, which are in a tropical jungle, and recover rock samples from below.

    Sieh tells Nemo that he would be supportive of anyone who wants to complete that work.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Smithsonian magazine and Smithsonian.com place a Smithsonian lens on the world, looking at the topics and subject matters researched, studied and exhibited by the Smithsonian Institution — science, history, art, popular culture and innovation — and chronicling them every day for our diverse readership.

     
  • richardmitnick 1:27 pm on December 28, 2019 Permalink | Reply
    Tags: Discover Magazine,   

    From Discover Magazine: “Quantum Computers Finally Beat Supercomputers in 2019” 

    DiscoverMag

    From Discover Magazine

    December 28, 2019
    Stephen Ornes

    1
    LSU physicist Jonathan Dowling (right), shown with alumnus Todd Moulder, has pushed the growth rate in quantum computing. (Credit: LSU)

    In his 2013 book, Schrödinger’s Killer App, Louisiana State University theoretical physicist Jonathan Dowling predicted what he called “super exponential growth.” He was right. Back in May, during Google’s Quantum Spring Symposium, computer engineer Hartmut Neven reported the company’s quantum computing chip had been gaining power at breakneck speed.

    2
    Google’s Sycamore chip is kept cool inside their quantum cryostat.
    (Image: © Eric Lucero/Google, Inc.)

    The subtext: We are venturing into an age of quantum supremacy — the point at which quantum computers outperform the best classical supercomputers in solving a well-defined problem.

    Engineers test the accuracy of quantum computing chips by using them to solve a problem, and then verifying the work with a classical machine. But in early 2019, that process became problematic, reported Neven, who runs Google’s Quantum Artificial Intelligence Lab. Google’s quantum chip was improving so quickly that his group had to commandeer increasingly large computers — and then clusters of computers — to check its work. It’s become clear that eventually, they’ll run out of machines.

    Case in point: Google announced in October that its 53-qubit quantum processor had needed only 200 seconds to complete a problem that would have required 10,000 years on a supercomputer.

    Neven’s group observed a “double exponential” growth rate in the chip’s computing power over a few months. Plain old exponential growth is already really fast: It means that from one step to the next, the value of something multiplies. Bacterial growth can be exponential if the number of organisms doubles during an observed time interval. So can computing power of classical computers under Moore’s Law, the idea that it doubles roughly every year or two. But under double exponential growth, the exponents have exponents. That makes a world of difference: Instead of a progression from 2 to 4 to 8 to 16 to 32 bacteria, for example, a double-exponentially growing colony in the same time would grow from 2 to 4 to 16 to 256 to 65,536.

    Neven credits the growth rate to two factors: the predicted way that quantum computers improve on the computational power of classical ones, and quick improvement of quantum chips themselves. Some began referring to this growth rate as “Neven’s Law.” Some theorists say such growth was unavoidable.

    We talked to Dowling (who suggests a more fitting moniker: the “Dowling-Neven Law”) about double exponential growth, his prediction and his underappreciated Beer Theory of Quantum Mechanics.

    Q: You saw double exponential growth on the horizon long before it showed up in a lab. How?

    A: Anytime there’s a new technology, if it is worthwhile, eventually it kicks into exponential growth in something. We see this with the internet, we saw this with classical computers. You eventually hit a point where all of the engineers figure out how to make this work, miniaturize it and then you suddenly run into exponential growth in terms of the hardware. If it doesn’t happen, that hardware falls off the face of the Earth as a nonviable technology.

    Q: So you weren’t surprised to see Google’s chip improving so quickly?

    A: I’m only surprised that it happened earlier than I expected. In my book, I said within the next 50 to 80 years. I guessed a little too conservatively.

    Q: You’re a theoretical physicist. Are you typically conservative in your predictions?

    People say I’m fracking nuts when I publish this stuff. I like to think that I’m the crazy guy that always makes the least conservative prediction. I thought this was far-out wacky stuff, and I was making the most outrageous prediction. That’s why it’s taking everybody by surprise. Nobody expected double exponential growth in processing power to happen this soon.

    Q: Given that quantum chips are getting so fast, can I buy my own quantum computer now?

    A: Most of the people think the quantum computer is a solved problem. That we can just wait, and Google will sell you one that can do whatever you want. But no. We’re in the [prototype] era. The number of qubits is doubling every six months, but the qubits are not perfect. They fail a lot and have imperfections and so forth. But Intel and Google and IBM aren’t going to wait for perfect qubits. The people who made the [first computers] didn’t say, “We’re going to stop making bigger computers until we figure out how to make perfect vacuum tubes.”

    Q: What’s the big deal about doing problems with quantum mechanics instead of classical physics?

    A: If you have 32 qubits, it’s like you have 232 parallel universes that are working on parts of your computation. Or like you have a parallel processor with 232 processors. But you only pay the electric bill in our universe.

    Q: Quantum mechanics gets really difficult, really fast. How do you deal with that?

    A: Everybody has their own interpretation of quantum mechanics. Mine is the Many Beers Interpretation of Quantum Mechanics. With no beer, quantum mechanics doesn’t make any sense. After one, two or three beers, it makes perfect sense. But once you get to six or 10, it doesn’t make any sense again. I’m on my first bottle, so I’m in the zone.

    See the full article here .

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
  • richardmitnick 2:18 pm on December 10, 2019 Permalink | Reply
    Tags: "Scientists Find a Shipworm That Eats and Lives Inside Rocks", , , Discover Magazine, , Lithoredo abatanica   

    From Discover Magazine : “Scientists Find a Shipworm That Eats, and Lives Inside, Rocks” 

    DiscoverMag

    From Discover Magazine

    1
    Unlike any other shipworm known to science, Lithoredo abatanica chews through, leaving behind twisted tunnels. (Credit: Marvin A. Altamia and J. Reuben Shipway)

    Between a rock and a hard place? That’s just where Lithoredo likes it.

    Researchers found the new-to-science shipworm, a kind of clam, in the Abatan River on the Philippines’ Bohol Island. It was a stunning sight.

    “It is unlike any other shipworm, both in its appearance and its unusual habits, and this was apparent from the very first moment I laid eyes on it,” says marine biologist Dan Distel, executive director of the Ocean Genome Legacy Center at Northeastern University and senior author of the June paper describing the animal in the journal Proceedings of the Royal Society B.

    Shipworms got their name because they bore through wood that’s in contact with water, eating the material. They leave behind tunnels lined with the calcium carbonate that they secrete, similar to the way their clam kin build shells. Shipworms have been a maritime plague for millennia, destroying boats and piers. But Lithoredo abatanica nibbled its way down a different evolutionary path. This shipworm eats rock.

    2
    Individuals such as this 4-inch-long specimen secrete calcium carbonate that hardens into a burrow lining. (Credit: Marvin A. Altamia and J. Reuben Shipway)

    Distel’s field colleagues, acting on a tip from an earlier French expedition about shipworms apparently boring into the Abatan River’s bedrock, had to strap on snorkeling gear to search for the animals.

    “[We] picked up these rocks, swam them over to the bank and proceeded to crack [them] open with a hammer and chisel,” says Reuben Shipway, the paper’s lead author and a marine biologist at the University of Portsmouth. “Splitting the rock open to reveal several shipworms inside was just so bizarre.”

    Specimens of Lithoredo range from less than an inch to more than a foot long. Perhaps not surprisingly, given its unique diet, the animal lacks the sharp, wood-chewing pseudo-teeth of all its relatives and instead has broad, spatula-like chompers.

    2
    Holes in a piece of limestone made by the new species of shipworm. (Credit: Marvin A. Altamia and J. Reuben Shipway)

    Finding the rock-eating shipworm raises a broader issue. Because the shell-like burrow linings of shipworms can survive in the fossil record long after the wood around them is gone, these tube-like structures have been used by researchers as a proxy for the presence of woody material in ancient environments.

    Lithoredo’s dining preference for limestone means that scientists can no longer make such an assumption. The animals who left the linings behind might have just been rocking out.

    “I think people tend to assume that nearly everything is known about the diversity of life on our planet, but nothing could be further from the truth,” says Distel. “The world is full of amazing creatures that have yet to be discovered, creatures that are stranger than fiction.”

    See the full article here.

    five-ways-keep-your-child-safe-school-shootings

    Please help promote STEM in your local schools.

    Stem Education Coalition

     
c
Compose new post
j
Next post/Next comment
k
Previous post/Previous comment
r
Reply
e
Edit
o
Show/Hide comments
t
Go to top
l
Go to login
h
Show/Hide help
shift + esc
Cancel
%d bloggers like this: