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  • richardmitnick 4:29 pm on December 7, 2022 Permalink | Reply
    Tags: "How far has nuclear fusion power come? We could be at a turning point for the technology", , , EAST experiment in China, , ITER Tokamak in Saint-Paul-lès-Durance France, Korea’s flagship experiment KSTAR, , , The Conversation (AU), The Joint European Torus [JET] tokamak generator based at the Culham Center for Fusion Energy located at the Culham Science Centre near Culham in Oxfordshire England, The National Ignition Facility at Lawrence Livermore National Laboratory in California   

    From “The Conversation (AU)” : “How far has nuclear fusion power come? We could be at a turning point for the technology” 

    From “The Conversation (AU)”

    12.6.22
    Nathan Garland
    Lecturer in Applied Mathematics and Physics
    Griffith University

    Matthew Hole
    Senior Research Fellow, Mathematical Sciences Institute
    Australian National University

    Our society faces the grand challenge of providing sustainable, secure and affordable means of generating energy, while trying to reduce carbon dioxide emissions to net zero around 2050.

    To date, developments in fusion power, which potentially ticks all these boxes, have been funded almost exclusively by the public sector. However, something is changing.

    Private equity investment in the global fusion industry has more than doubled in just one year – from US$2.1 billion in 2021 to US$4.7 billion in 2022, according to a survey from the Fusion Industry Association.

    So, what is driving this recent change? There’s lots to be excited about.

    The U.K.-based JET laboratory recently managed to produce and maintain a comparatively high level of thermal energy over a five-second period, a promising sign for the viability of nuclear fusion.
    Courtesy of Euro Fusion.

    Before we explore that, let’s take a quick detour to recap what fusion power is.

    Merging atoms together

    Fusion works the same way our Sun does, by merging two heavy hydrogen atoms under extreme heat and pressure to release vast amounts of energy.

    It’s the opposite of the fission process used by nuclear power plants, in which atoms are split to release large amounts of energy.

    Sustaining nuclear fusion at scale has the potential to produce a safe, clean, almost inexhaustible power source.

    Our Sun sustains fusion at its core with a plasma of charged particles at around 15 million degrees Celsius. Down on Earth, we are aiming for hundreds of millions of degrees Celsius, because we don’t have the enormous mass of the Sun compressing the fuel down for us.

    Scientists and engineers have worked out several designs for how we might achieve this, but most fusion reactors use strong magnetic fields to “bottle” and confine the hot plasma.

    Generally, the main challenge to overcome on our road to commercial fusion power is to provide environments that can contain the intense burning plasma needed to produce a fusion reaction that is self-sustaining, producing more energy than was needed to get it started.

    Joining the public and private

    Fusion development has been progressing since the 1950s. Most of it was driven by government funding for fundamental science.

    Now, a growing number of private fusion companies around the world are forging ahead towards commercial fusion energy. A change in government attitudes has been crucial to this.

    The US and UK governments are fostering public-private partnerships to complement their strategic research programs.

    For example, the White House recently announced it would develop a “bold decadal vision for commercial fusion energy”.

    In the United Kingdom, the government has invested in a program aimed at connecting a fusion generator to the national electricity grid.

    The technology has actually advanced, too.

    In addition to public-private resourcing, the technologies we need for fusion plants have come along in leaps and bounds.

    In 2021, MIT scientists and Commonwealth Fusion Systems developed a record-breaking magnet that will allow them to build a compact fusion device called SPARC “that is substantially smaller, lower cost, and on a faster timeline”.

    In recent years, several fusion experiments have also reached the all-important milestone of sustaining plasma temperatures of 100 million degrees Celsius or above. These include the EAST experiment in China, Korea’s flagship experiment KSTAR, and UK-based company Tokamak Energy.

    These incredible feats demonstrate an unprecedented ability to replicate conditions found inside our Sun and keep extremely hot plasma trapped long enough to encourage fusion to occur.

    In February, the Joint European Torus [above]– the world’s most powerful operational tokamak – announced world-record energy confinement.

    And the next-step fusion energy experiment to demonstrate net power gain, ITER, is under construction in France and now about 80% complete.

    Magnets aren’t the only path to fusion either. In November 2021, The National Ignition Facility at Lawrence Livermore National Laboratory in California achieved a historic step forward for inertial confinement fusion.

    By focusing nearly 200 powerful lasers to confine and compress a target the size of a pencil’s eraser, they produced a small fusion “hot spot” generating fusion energy over a short time period.

    In Australia, a company called HB11 is developing proton-boron fusion technology through a combination of high-powered lasers and magnetic fields.

    Fusion and renewables can go hand in hand

    It is crucial that investment in fusion is not at the cost of other forms of renewable energy and the transition away from fossil fuels.

    We can afford to expand adoption of current renewable energy technology like solar, wind, and pumped hydro while also developing next-generation solutions for electricity production.

    This exact strategy was outlined recently by the United States in its Net-Zero Game Changers Initiative. In this plan, resource investment will be targeted to developing a path to rapid decarbonization in parallel with the commercial development of fusion.

    History shows us that incredible scientific and engineering progress is possible when we work together with the right resources – the rapid development of COVID-19 vaccines is just one recent example.

    It is clear many scientists, engineers, and now governments and private investors (and even fashion designers) have decided fusion energy is a solution worth pursuing, not a pipe dream. Right now, it’s the best shot we’ve yet had to make fusion power a viable reality.

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation (AU) launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.

    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 12:03 pm on November 30, 2022 Permalink | Reply
    Tags: "Where did the Earth’s oxygen come from? New study hints at an unexpected source", A tantalizing new possibility for oxygenation: that at least some of the Earth’s early oxygen came from a tectonic source via the movement and destruction of the Earth’s crust., Aerobics, , , , , In the deep past — as far back as the Neoarchean era 2.8 to 2.5 billion years ago — this oxygen was almost absent., , The amount of oxygen in the Earth’s atmosphere makes it a habitable planet., The Archean eon represents one third of our planet’s history from 2.5 billion years ago to four billion years ago., The Conversation (AU), There is considerable debate over whether plate tectonics operated back in the Archean era., This early Earth was a water-world covered in green oceans and shrouded in a methane haze and completely lacking multi-cellular life., This research aimed to test whether the absence of oxidized materials in Archean bottom waters and sediments could prevent the formation of oxidized magmas.   

    From “The Conversation (AU)” : “Where did the Earth’s oxygen come from? New study hints at an unexpected source” 

    From “The Conversation (AU)”

    11.28.22
    David Mole
    Postdoctoral fellow, Earth Sciences
    Laurentian University

    Adam Charles Simon
    Arthur F. Thurnau Professor, Earth & Environmental Sciences
    University of Michigan

    Xuyang Meng
    Postdoctoral Fellow, Earth and Environmental Sciences
    University of Michigan

    1
    An artist’s impression of the Earth around 2.7 billion years ago in the Archean Eon. With green iron-rich seas, an orange methane-rich atmosphere and a surface dominated by oceans, the Archean Earth would have been a very different place. (Illustration by Andrey Atuchin), Author provided (no reuse)[Used under “Fair Use” for academic teaching purposes.]

    “The amount of oxygen in the Earth’s atmosphere makes it a habitable planet.

    Twenty-one per cent of the atmosphere consists of this life-giving element. But in the deep past — as far back as the Neoarchean era 2.8 to 2.5 billion years ago — this oxygen was almost absent [Science Advances (below)].

    So, how did Earth’s atmosphere become oxygenated?

    Our research, published in Nature Geoscience [below], adds a tantalizing new possibility: that at least some of the Earth’s early oxygen came from a tectonic source via the movement and destruction of the Earth’s crust.

    The Archean Earth

    The Archean eon represents one third of our planet’s history from 2.5 billion years ago to four billion years ago.

    This alien Earth was a water-world, covered in green oceans, shrouded in a methane haze and completely lacking multi-cellular life. Another alien aspect of this world was the nature of its tectonic activity.

    2
    The cross-section of a subduction zone, where oceanic lithosphere slides under a continental margin. (Xuyang Meng), Author provided (no reuse)[Used under “Fair Use” for academic teaching purposes.]

    On modern Earth, the dominant tectonic activity is called plate tectonics, where oceanic crust — the outermost layer of the Earth under the oceans — sinks into the Earth’s mantle (the area between the Earth’s crust and its core) at points of convergence called subduction zones.

    However, there is considerable debate over whether plate tectonics operated back in the Archean era.

    One feature of modern subduction zones is their association with oxidized magmas. These magmas are formed when oxidized sediments and bottom waters — cold, dense water near the ocean floor — are introduced into the Earth’s mantle [PNAS (below)]. This produces magmas with high oxygen and water contents.

    Our research aimed to test whether the absence of oxidized materials in Archean bottom waters and sediments could prevent the formation of oxidized magmas. The identification of such magmas in Neoarchean magmatic rocks could provide evidence that subduction and plate tectonics occurred 2.7 billion years ago.

    The experiment

    We collected samples of 2750- to 2670-million-year-old granitoid rocks from across the Abitibi-Wawa subprovince of the Superior Province — the largest preserved Archean continent stretching over 2000 km from Winnipeg, Manitoba to far-eastern Quebec. This allowed us to investigate the level of oxidation of magmas generated across the Neoarchean era.

    Measuring the oxidation-state of these magmatic rocks — formed through the cooling and crystalization of magma or lava — is challenging. Post-crystallization events may have modified these rocks through later deformation, burial or heating.

    So, we decided to look at the mineral apatite which is present in the zircon crystals in these rocks. Zircon crystals can withstand the intense temperatures and pressures of the post-crystallization events. They retain clues about the environments in which they were originally formed and provide precise ages for the rocks themselves.

    Small apatite crystals that are less than 30 microns wide — the size of a human skin cell — are trapped in the zircon crystals. They contain sulfur. By measuring the amount of sulfur in apatite, we can establish whether the apatite grew from an oxidized magma.

    3
    Map of the Superior Province that stretches from central Manitoba to eastern Quebec in Canada. (Xuyang Meng), Author provided.

    We were able to successfully measure the oxygen fugacity of the original Archean magma — which is essentially the amount of free oxygen in it — using a specialized technique called X-ray Absorption Near Edge Structure Spectroscopy (S-XANES) at the Advanced Photon Source synchrotron at The DOE’s Argonne National Laboratory in Illinois.

    Creating oxygen from water?

    We found that the magma sulfur content, which was initially around zero, increased to 2000 parts per million around 2705 million years. This indicated the magmas had become more sulfur-rich. Additionally, the predominance of S6+ — a type of sulfer ion — in the apatite [Journal of Petrology (below)] suggested that the sulfur was from an oxidized source, matching the data from the host zircon crystals [Precambrian Research (below)].

    These new findings indicate that oxidized magmas did form in the Neoarchean era 2.7 billion years ago. The data show that the lack of dissolved oxygen in the Archean ocean reservoirs did not prevent the formation of sulfur-rich, oxidized magmas in the subduction zones. The oxygen in these magmas must have come from another source, and was ultimately released into the atmosphere during volcanic eruptions.

    We found that the occurrence of these oxidized magmas correlates with major gold mineralization events in the Superior Province and Yilgarn Craton (Western Australia), demonstrating a connection between these oxygen-rich sources and global world-class ore deposit formation.

    The implications of these oxidized magmas go beyond the understanding of early Earth geodynamics. Previously, it was thought unlikely that Archean magmas could be oxidized, when the ocean water [Science (below)] and ocean floor rocks or sediments [Nature (below)] were not.

    While the exact mechanism is unclear, the occurrence of these magmas suggests that the process of subduction, where ocean water is taken hundreds of kilometres into our planet, generates free oxygen. This then oxidizes the overlying mantle.

    Our study shows that Archean subduction could have been a vital, unforeseen factor in the oxygenation of the Earth, the early whiffs of oxygen 2.7 billion years ago [Nature Geoscience (below)] and also the Great Oxidation Event, which marked an increase in atmospheric oxygen by two per cent 2.45 to 2.32 billion years ago [Treatise on Geochemistry (Second Edition) (below)].

    As far as we know, the Earth is the only place in the solar system — past or present — with plate tectonics and active subduction. This suggests that this study could partly explain the lack of oxygen and, ultimately, life on the other rocky planets in the future as well.”

    Science papers:
    PNAS 2019
    Science Advances 2020
    Journal of Petrology 2021
    Precambrian Research 2021
    See these above science papers for instructive material with images and tables.
    Treatise on Geochemistry (Second Edition) 2014
    Nature Geoscience 2017
    Nature 2018
    Science 2002
    Nature Geoscience

    See the full article here .

    Comments are invited and will be appreciated, especially if the reader finds any errors which I can correct. Use “Reply”.

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation (AU) launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.

    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 10:08 pm on November 16, 2022 Permalink | Reply
    Tags: "Powerful linear accelerator begins smashing atoms – 2 scientists on the team explain how it could reveal rare forms of matter", 1. What are the properties of atomic nuclei with a large difference between the numbers of protons and neutrons?, 2. How are elements formed in the cosmos?, 3. Do physicists understand the fundamental symmetries of the universe like why there is more matter than antimatter in the universe?, 4. How can the information from rare isotopes be applied in medicine and industry and national security?, A community of roughly 1600 nuclear scientists from all over the world has been waiting for a decade to begin doing science enabled by the new particle accelerator., At full strength the FRIB will be the most powerful heavy-ion accelerator on Earth., , , Even though the facility is currently running at only a fraction of its full power multiple scientific collaborations working at FRIB have already produced and detected about 100 rare isotopes., Experiments at FRIB promise to provide new insights into the fundamental nature of the universe., Nuclear Chemistry, , Over the coming years FRIB is set to explore four big questions in nuclear physics:, , The Conversation (AU), The Facility for Rare Isotope Beams [FRIB], , The study of rare isotopes   

    From The Facility for Rare Isotope Beams [FRIB] At The Michigan State University Via “The Conversation (AU)” : “Powerful linear accelerator begins smashing atoms – 2 scientists on the team explain how it could reveal rare forms of matter” 

    From The Facility for Rare Isotope Beams [FRIB]

    At

    Michigan State Bloc

    The Michigan State University

    Via

    “The Conversation (AU)”

    11.14.22

    1
    A new particle accelerator at Michigan State University is set to discover thousands of never-before-seen isotopes. Facility for Rare Isotope Beams, CC BY-ND

    Sean Liddick
    Associate Professor of Chemistry, Michigan State University

    Artemis Spyrou
    Professor of Nuclear Physics, Michigan State University

    “Just a few hundred feet from where we are sitting is a large metal chamber devoid of air and draped with the wires needed to control the instruments inside. A beam of particles passes through the interior of the chamber silently at around half the speed of light until it smashes into a solid piece of material, resulting in a burst of rare isotopes.

    This is all taking place in the Facility for Rare Isotope Beams, or FRIB, which is operated by Michigan State University for The DOE Office of Science. Starting in May 2022, national and international teams of scientists converged at Michigan State University and began running scientific experiments at FRIB with the goal of creating, isolating and studying new isotopes. The experiments promised to provide new insights into the fundamental nature of the universe.

    We are two professors in nuclear chemistry and nuclear physics who study rare isotopes. Isotopes are, in a sense, different flavours of an element with the same number of protons in their nucleus but different numbers of neutrons.

    The accelerator at FRIB started working at low power, but when it finishes ramping up to full strength, it will be the most powerful heavy-ion accelerator on Earth. By accelerating heavy ions – electrically charged atoms of elements – FRIB will allow scientists like us to create and study thousands of never-before-seen isotopes. A community of roughly 1,600 nuclear scientists from all over the world has been waiting for a decade to begin doing science enabled by the new particle accelerator.

    The first experiments at FRIB were completed over the summer of 2022. Even though the facility is currently running at only a fraction of its full power, multiple scientific collaborations working at FRIB have already produced and detected about 100 rare isotopes. These early results are helping researchers learn about some of the rarest physics in the universe.


    Put some Uranium 238 in a cloud chamber to see the radioactive particles.

    What is a rare isotope?

    It takes incredibly high amounts of energy to produce most isotopes. In nature, heavy rare isotopes are produced during the cataclysmic deaths of massive stars called supernovas or during the merging of two neutron stars.

    To the naked eye, two isotopes of any element look and behave the same way – all isotopes of the element mercury would look just like the liquid metal used in old thermometers. However, because the nuclei of isotopes of the same element have different numbers of neutrons, they differ in how long they live, what type of radioactivity they emit and in many other ways.

    For example, some isotopes are stable and do not decay or emit radiation, so they are common in the universe. Other isotopes of the very same element can be radioactive so they inevitably decay away as they turn into other elements. Since radioactive isotopes disappear over time, they are relatively rarer.

    Not all decay happens at the same rate though. Some radioactive elements – like potassium-40 – emit particles through decay at such a low rate that a small amount of the isotope can last for billions of years. Other, more highly radioactive isotopes like magnesium-38 exist for only a fraction of a second before decaying away into other elements. Short-lived isotopes, by definition, do not survive long and are rare in the universe. So if you want to study them, you have to make them yourself.

    2
    FRIB at Michigan State University for the DOE delineated.

    Creating isotopes in a lab

    While only about 250 isotopes naturally occur on Earth, theoretical models predict that about 7,000 isotopes should exist in nature. Scientists have used particle accelerators to produce around 3,000 of these rare isotopes.

    3
    The green-colored chambers use electromagnetic waves to accelerate charged ions to nearly half the speed of light. Facility for Rare Isotope Beams, CC BY-ND.

    The FRIB accelerator is 1,600 feet long and made of three segments folded in roughly the shape of a paperclip. Within these segments are numerous, extremely cold vacuum chambers that alternatively pull and push the ions using powerful electromagnetic pulses. FRIB can accelerate any naturally occurring isotope – whether it is as light as oxygen or as heavy as uranium – to approximately half the speed of light.

    To create radioactive isotopes, you only need to smash this beam of ions into a solid target like a piece of beryllium metal or a rotating disk of carbon.

    4
    There are many different instruments designed to measure specific attributes of the particles created during experiments at FRIB – like this instrument called FDSi, which is built to measure charged particles, neutrons and photons. Facility for Rare Isotope Beams, CC BY-ND.

    The impact of the ion beam on the fragmentation target breaks the nucleus of the stable isotope apart and produces many hundreds of rare isotopes simultaneously. To isolate the interesting or new isotopes from the rest, a separator sits between the target and the sensors. Particles with the right momentum and electrical charge will be passed through the separator while the rest are absorbed. Only a subset of the desired isotopes will reach the many instruments built to observe the nature of the particles.

    The probability of creating any specific isotope during a single collision can be very small. The odds of creating some of the rarer exotic isotopes can be on the order of 1 in a quadrillion – roughly the same odds as winning back-to-back Mega Millions jackpots. But the powerful beams of ions used by FRIB contain so many ions and produce so many collisions in a single experiment that the team can reasonably expect to find even the rarest of isotopes. According to calculations, FRIB’s accelerator should be able to produce approximately 80% of all theorized isotopes.

    The first two FRIB scientific experiments

    A multi-institution team led by researchers at The DOE’s Lawrence Berkeley National Laboratory, The DOE’s Oak Ridge National Laboratory, University of Tennessee, Knoxville, Mississippi State University and Florida State University, together with researchers at MSU, began running the first experiment at FRIB on May 9, 2022. The group directed a beam of calcium-48 – a calcium nucleus with 48 neutrons instead of the usual 20 – into a beryllium target at 1 kW of power. Even at one quarter of a percent of the facility’s 400-kW maximum power, approximately 40 different isotopes passed through the separator to the instruments.

    The FDSi device recorded the time each ion arrived, what isotope it was and when it decayed away. Using this information, the collaboration deduced the half-lives of the isotopes; the team has already reported on five previously unknown half-lives.

    The second FRIB experiment began on June 15, 2022, led by a collaboration of researchers from The DOE’s Lawrence Livermore National Laboratory, ORNL, UTK and MSU. The facility accelerated a beam of selenium-82 and used it to produce rare isotopes of the elements scandium, calcium and potassium. These isotopes are commonly found in neutron stars, and the goal of the experiment was to better understand what type of radioactivity these isotopes emit as they decay. Understanding this process could shed light on how neutron stars lose energy.

    The first two FRIB experiments were just the tip of the iceberg of this new facility’s capabilities. Over the coming years, FRIB is set to explore four big questions in nuclear physics: First, what are the properties of atomic nuclei with a large difference between the numbers of protons and neutrons? Second, how are elements formed in the cosmos? Third, do physicists understand the fundamental symmetries of the universe, like why there is more matter than antimatter in the universe? Finally, how can the information from rare isotopes be applied in medicine, industry and national security?”

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Michigan State Campus

    Michigan State University is a public research university located in East Lansing, Michigan, United States. Michigan State University was founded in 1855 and became the nation’s first land-grant institution under the Morrill Act of 1862, serving as a model for future land-grant universities.

    The university was founded as the Agricultural College of the State of Michigan, one of the country’s first institutions of higher education to teach scientific agriculture. After the introduction of the Morrill Act, the college became coeducational and expanded its curriculum beyond agriculture. Today, Michigan State University is one of the largest universities in the United States (in terms of enrollment) and has approximately 634,300 living alumni worldwide.

    U.S. News & World Report ranks its graduate programs the best in the U.S. in elementary teacher’s education, secondary teacher’s education, industrial and organizational psychology, rehabilitation counseling, African history (tied), supply chain logistics and nuclear physics in 2019. Michigan State University pioneered the studies of packaging, hospitality business, supply chain management, and communication sciences. Michigan State University is a member of the Association of American Universities and is classified among “R1: Doctoral Universities – Very high research activity”. The university’s campus houses the National Superconducting Cyclotron Laboratory, the W. J. Beal Botanical Garden, the Abrams Planetarium, the Wharton Center for Performing Arts, the Eli and Edythe Broad Art Museum, the Facility for Rare Isotope Beams, and the country’s largest residence hall system.

    Research

    The university has a long history of academic research and innovation. In 1877, botany professor William J. Beal performed the first documented genetic crosses to produce hybrid corn, which led to increased yields. Michigan State University dairy professor G. Malcolm Trout improved the process for the homogenization of milk in the 1930s, making it more commercially viable. In the 1960s, Michigan State University scientists developed cisplatin, a leading cancer fighting drug, and followed that work with the derivative, carboplatin. Albert Fert, an Adjunct professor at Michigan State University, was awarded the 2007 Nobel Prize in Physics together with Peter Grünberg.

    Today Michigan State University continues its research with facilities such as the Department of Energy -sponsored Plant Research Laboratory and a particle accelerator called the National Superconducting Cyclotron Laboratory [below]. The Department of Energy Office of Science named Michigan State University as the site for the Facility for Rare Isotope Beams (FRIB). The $730 million facility will attract top researchers from around the world to conduct experiments in basic nuclear science, astrophysics, and applications of isotopes to other fields.

    Michigan State University FRIB [Facility for Rare Isotope Beams] .

    In 2004, scientists at the Cyclotron produced and observed a new isotope of the element germanium, called Ge-60 In that same year, Michigan State University, in consortium with the University of North Carolina at Chapel Hill and the government of Brazil, broke ground on the 4.1-meter Southern Astrophysical Research Telescope (SOAR) in the Andes Mountains of Chile.

    The consortium telescope will allow the Physics & Astronomy department to study galaxy formation and origins. Since 1999, MSU has been part of a consortium called the Michigan Life Sciences Corridor, which aims to develop biotechnology research in the State of Michigan. Finally, the College of Communication Arts and Sciences’ Quello Center researches issues of information and communication management.


    The Michigan State University Spartans compete in the NCAA Division I Big Ten Conference. Michigan State Spartans football won the Rose Bowl Game in 1954, 1956, 1988 and 2014, and the university claims a total of six national football championships. Spartans men’s basketball won the NCAA National Championship in 1979 and 2000 and has attained the Final Four eight times since the 1998–1999 season. Spartans ice hockey won NCAA national titles in 1966, 1986 and 2007. The women’s cross country team was named Big Ten champions in 2019. In the fall of 2019, MSU student-athletes posted all-time highs for graduation success rates and federal graduation rates, according to NCAA statistics.

     
  • richardmitnick 2:11 pm on November 11, 2022 Permalink | Reply
    Tags: , , , , , The Conversation (AU), , , "We tested Einstein’s theory of gravity on the scale of the universe – here’s what we found"   

    From The University of Portsmouth (UK) And Simon Fraser University (CA) Via “The Conversation (AU)” : “We tested Einstein’s theory of gravity on the scale of the universe – here’s what we found” 

    From The University of Portsmouth (UK)

    And

    Simon Fraser University (CA)

    Via

    “The Conversation (AU)”

    11.10.11

    Kazuya Koyama
    Professor of Cosmology, University of Portsmouth

    Levon Pogosian
    Professor of Physics, Simon Fraser University

    1
    Thousands of galaxies seen by the James Webb Space Telescope. Credit: NASA

    Everything in the universe has gravity – and feels it too. Yet this most common of all fundamental forces is also the one that presents the biggest challenges to physicists. Albert Einstein’s Theory of General Relativity has been remarkably successful in describing the gravity of stars and planets, but it doesn’t seem to apply perfectly on all scales.

    General Relativity has passed many years of observational tests, from Eddington’s measurement of the deflection of starlight by the Sun in 1919 to the recent detection of gravitational waves.

    However, gaps in our understanding start to appear when we try to apply it to extremely small distances, where the laws of quantum mechanics operate, or when we try to describe the entire universe.

    Our new study, published in Nature Astronomy [below], has now tested Einstein’s theory on the largest of scales. We believe our approach may one day help resolve some of the biggest mysteries in Cosmology, and the results hint that the Theory of General Relativity may need to be tweaked on this scale.

    Faulty model?

    Quantum theory predicts that empty space, the vacuum, is packed with energy. We do not notice its presence because our devices can only measure changes in energy rather than its total amount.

    However, according to Einstein, the vacuum energy has a repulsive gravity – it pushes the empty space apart. Interestingly, in 1998, it was discovered that the expansion of the universe is in fact accelerating (a finding awarded with the 2011 Nobel prize in physics).

    However, the amount of vacuum energy, or dark energy as it has been called, necessary to explain the acceleration is many orders of magnitude smaller than what quantum theory predicts.

    Hence the big question, dubbed “the old cosmological constant problem”, is whether the vacuum energy actually gravitates – exerting a gravitational force and changing the expansion of the universe.

    If yes, then why is its gravity so much weaker than predicted? If the vacuum does not gravitate at all, what is causing the cosmic acceleration?

    We don’t know what dark energy is, but we need to assume it exists in order to explain the universe’s expansion. Similarly, we also need to assume there is a type of invisible matter presence, dubbed dark matter, to explain how galaxies and clusters evolved to be the way we observe them today.

    These assumptions are baked into scientists’ standard cosmological theory, called the lambda cold dark matter (LCDM) model – suggesting there is 70% dark energy, 25% dark matter and 5% ordinary matter in the cosmos. And this model has been remarkably successful in fitting all the data collected by cosmologists over the past 20 years.

    But the fact that most of the universe is made up of dark forces and substances, taking odd values that don’t make sense, has prompted many physicists to wonder if Einstein’s theory of gravity needs modification to describe the entire universe.

    A new twist appeared a few years ago when it became apparent that different ways of measuring the rate of cosmic expansion, dubbed the “Hubble constant”, give different answers – a problem known as the “Hubble tension”.

    The disagreement, or tension, is between two values of the Hubble constant. One is the number predicted by the LCDM cosmological model, which has been developed to match the light left over from the Big Bang (the cosmic microwave background radiation). The other is the expansion rate measured by observing exploding stars known as supernovas in distant galaxies.

    Many theoretical ideas have been proposed for ways of modifying LCDM to explain the Hubble tension. Among them are alternative gravity theories.

    Digging for answers

    We can design tests to check if the universe obeys the rules of Einstein’s theory. General Relativity describes gravity as the curving or warping of space and time, bending the pathways along which light and matter travel. Importantly, it predicts that the trajectories of light rays and matter should be bent by gravity in the same way.

    Together with a team of cosmologists, we put the basic laws of general relativity to test. We also explored whether modifying Einstein’s theory could help resolve some of the open problems of cosmology, such as the Hubble tension.

    To find out whether General Relativity is correct on large scales, we set out, for the first time, to simultaneously investigate three aspects of it. These were the expansion of the universe, the effects of gravity on light and the effects of gravity on matter.

    Using a statistical method known as the Bayesian inference, we reconstructed the gravity of the universe through cosmic history in a computer model based on these three parameters. We could estimate the parameters using the cosmic microwave background data from the Planck satellite, supernova catalogues as well as observations of the shapes and distribution of distant galaxies by the SDSS and DES telescopes. We then compared our reconstruction to the prediction of the LCDM model (essentially Einstein’s model).

    ___________________________________________________________________
    Apache Point Observatory
    SDSS Telescope at Apache Point Observatory, near Sunspot NM, USA, Altitude 2,788 meters (9,147 ft).

    Apache Point Observatory near Sunspot, New Mexico Altitude 2,788 meters (9,147 ft).
    ___________________________________________________________________
    The Dark Energy Survey

    Dark Energy Camera [DECam] built at The DOE’s Fermi National Accelerator Laboratory.

    NOIRLab National Optical Astronomy Observatory Cerro Tololo Inter-American Observatory (CL) Victor M Blanco 4m Telescope which houses the Dark-Energy-Camera – DECam at Cerro Tololo, Chile at an altitude of 7200 feet.

    NOIRLabNSF NOIRLab NOAO Cerro Tololo Inter-American Observatory(CL) approximately 80 km to the East of La Serena, Chile, at an altitude of 2200 meters.

    The Dark Energy Survey is an international, collaborative effort to map hundreds of millions of galaxies, detect thousands of supernovae, and find patterns of cosmic structure that will reveal the nature of the mysterious dark energy that is accelerating the expansion of our Universe. The Dark Energy Survey began searching the Southern skies on August 31, 2013.

    According to Albert Einstein’s Theory of General Relativity, gravity should lead to a slowing of the cosmic expansion. Yet, in 1998, two teams of astronomers studying distant supernovae made the remarkable discovery that the expansion of the universe is speeding up.

    Nobel Prize in Physics for 2011 Expansion of the Universe

    4 October 2011

    The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2011

    with one half to

    Saul Perlmutter
    The Supernova Cosmology Project
    The DOE’s Lawrence Berkeley National Laboratory and The University of California-Berkeley,

    and the other half jointly to

    Brian P. SchmidtThe High-z Supernova Search Team, The Australian National University, Weston Creek, Australia.

    and

    Adam G. Riess

    The High-z Supernova Search Team,The Johns Hopkins University and The Space Telescope Science Institute, Baltimore, MD.

    Written in the stars

    “Some say the world will end in fire, some say in ice…” *

    What will be the final destiny of the Universe? Probably it will end in ice, if we are to believe this year’s Nobel Laureates in Physics. They have studied several dozen exploding stars, called supernovae, and discovered that the Universe is expanding at an ever-accelerating rate. The discovery came as a complete surprise even to the Laureates themselves.

    In 1998, cosmology was shaken at its foundations as two research teams presented their findings. Headed by Saul Perlmutter, one of the teams had set to work in 1988. Brian Schmidt headed another team, launched at the end of 1994, where Adam Riess was to play a crucial role.

    The research teams raced to map the Universe by locating the most distant supernovae. More sophisticated telescopes on the ground and in space, as well as more powerful computers and new digital imaging sensors (CCD, Nobel Prize in Physics in 2009), opened the possibility in the 1990s to add more pieces to the cosmological puzzle.

    The teams used a particular kind of supernova, called Type 1a supernova. It is an explosion of an old compact star that is as heavy as the Sun but as small as the Earth. A single such supernova can emit as much light as a whole galaxy. All in all, the two research teams found over 50 distant supernovae whose light was weaker than expected – this was a sign that the expansion of the Universe was accelerating. The potential pitfalls had been numerous, and the scientists found reassurance in the fact that both groups had reached the same astonishing conclusion.

    For almost a century, the Universe has been known to be expanding as a consequence of the Big Bang about 14 billion years ago. However, the discovery that this expansion is accelerating is astounding. If the expansion will continue to speed up the Universe will end in ice.

    The acceleration is thought to be driven by dark energy, but what that dark energy is remains an enigma – perhaps the greatest in physics today. What is known is that dark energy constitutes about three quarters of the Universe. Therefore the findings of the 2011 Nobel Laureates in Physics have helped to unveil a Universe that to a large extent is unknown to science. And everything is possible again.

    *Robert Frost, Fire and Ice, 1920
    ______________________________________________________________________________

    We found interesting hints of a possible mismatch with Einstein’s prediction, albeit with rather low statistical significance. This means that there is nevertheless a possibility that gravity works differently on large scales, and that the theory of general relativity may need to be tweaked.

    Our study also found that it is very difficult to solve the Hubble tension problem by only changing the theory of gravity. The full solution would probably require a new ingredient in the cosmological model, present before the time when protons and electrons first combined to form hydrogen just after the Big Bang, such as a special form of dark matter, an early type of dark energy or primordial magnetic fields. Or, perhaps, there’s a yet unknown systematic error in the data.

    That said, our study has demonstrated that it is possible to test the validity of general relativity over cosmological distances using observational data. While we haven’t yet solved the Hubble problem, we will have a lot more data from new probes in a few years.

    This means that we will be able to use these statistical methods to continue tweaking general relativity, exploring the limits of modifications, to pave the way to resolving some of the open challenges in cosmology.

    Science paper:
    Nature Astronomy

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Simon Fraser University (CA) is a public research university in British Columbia, Canada, with three campuses: Burnaby (main campus), Surrey, and Vancouver. The 170-hectare (420-acre) main Burnaby campus on Burnaby Mountain, located 20 kilometres (12 mi) from downtown Vancouver, was established in 1965 and comprises more than 30,000 students and 160,000 alumni. The university was created in an effort to expand higher education across Canada.

    Simon Fraser University (CA) is a member of multiple national and international higher education, including the Association of Commonwealth Universities, International Association of Universities, and Universities Canada (CA). Simon Fraser University has also partnered with other universities and agencies to operate joint research facilities such as the TRIUMF- Canada’s particle accelerator centre [Centre canadien d’accélération des particules] (CA) for particle and nuclear physics, which houses the world’s largest cyclotron, and Bamfield Marine Station, a major centre for teaching and research in marine biology.

    Undergraduate and graduate programs at Simon Fraser University (CA) operate on a year-round, three-semester schedule. Consistently ranked as Canada’s top comprehensive university and named to the Times Higher Education list of 100 world universities under 50, Simon Fraser University (CA)is also the first Canadian member of the National Collegiate Athletic Association, the world’s largest college sports association. In 2015, Simon Fraser University (CA) became the second Canadian university to receive accreditation from the Northwest Commission on Colleges and Universities. Simon Fraser University (CA) faculty and alumni have won 43 fellowships to the Royal Society of Canada [Société royale du Canada](CA), three Rhodes Scholarships and one Pulitzer Prize. Among the list of alumni includes two former premiers of British Columbia, Gordon Campbell and Ujjal Dosanjh, owner of the Vancouver Canucks NHL team, Francesco Aquilini, Prime Minister of Lesotho, Pakalitha Mosisili, director at the MPG Society [MPG Gesellschaft](DE) , Robert Turner, and humanitarian and cancer research activist, Terry Fox.

    The University of Portsmouth (UK) is a public university in the city of Portsmouth, Hampshire, England. The history of the university dates back to 1908, when the Park building opened as a Municipal college and public library. It was previously known as Portsmouth Polytechnic until 1992, when it was granted university status through the Further and Higher Education Act 1992. It is ranked among the Top 100 universities under 50 in the world.

    We’re a New Breed of University
    We’re proud to be a breath of fresh air in the academic world – a place where everyone gets the support they need to achieve their best.
    We’re always discovering. Through the work we do, we engage with our community and world beyond our hometown. We don’t fit the mould, we break it.
    We educate and transform the lives of our students and the people around us. We recruit students for their promise and potential and for where they want to go.
    We stand out, not just in the UK but in the world, in innovation and research, with excellence in areas from cosmology and forensics to cyber security, epigenetics and brain tumour research.
    Just as the world keeps moving, so do we. We’re closely involved with our local community and we take our ideas out into the global marketplace. We partner with business, industry and government to help improve, navigate and set the course for a better future.
    Since the first day we opened our doors, our story has been about looking forward. We’re interested in the future, and here to help you shape it.
    The university offers a range of disciplines, from Pharmacy, International relations and politics, to Mechanical Engineering, Paleontology, Criminology, Criminal Justice, among others. The Guardian University Guide 2018 ranked its Sports Science number one in England, while Criminology, English, Social Work, Graphic Design and Fashion and Textiles courses are all in the top 10 across all universities in the UK. Furthermore, 89% of its research conducted in Physics, and 90% of its research in Allied Health Professions (e.g. Dentistry, Nursing and Pharmacy) have been rated as world-leading or internationally excellent in the most recent Research Excellence Framework (REF2014).

    The University is a member of the University Alliance and The Channel Islands Universities Consortium. Alumni include Tim Peake, Grayson Perry, Simon Armitage and Ben Fogle.
    Portsmouth was named the UK’s most affordable city for students in the Natwest Student Living Index 2016. On Friday 4 May 2018, the University of Portsmouth was revealed as the main shirt sponsor of Portsmouth F.C. for the 2018–19, 2019–20 and 2020–21 seasons.

     
  • richardmitnick 9:45 am on November 9, 2022 Permalink | Reply
    Tags: "1. A cat can be dead and alive", "2. Simple analogies can explain entanglement", "3. Nature is unreal and ‘non-local’", "4. Nobody understands quantum mechanics", "Four common misconceptions about quantum physics", , Bell’s theorem (a theoretical test created by the physicist John Stewart Bell), Entanglement is a quantum property which links two different particles so that if you measure one you automatically and instantly know the state of the other – no matter how far apart they are., From a 21st-century perspective quantum physics is neither mathematically nor conceptually particularly difficult for scientists., In quantum physics each particle’s state is also a wave., , Quantum Mechanics is bizarre and counter-intuitive., Quantum particles can be in two states – for example in two locations – at the same time. We call this a superposition., The Conversation (AU), , The idea that measuring one entangled card changes the state of the other is not true. Quantum particles are mysteriously correlated in ways we can’t describe with everyday logic or language.   

    From “The Conversation (AU)” : “Four common misconceptions about quantum physics” 

    From “The Conversation (AU)”

    11.8.22

    1
    Shrödinger’s cat is world famous, but what does it really mean? Robert Couse-Baker/Flickr, CC BY-SA.

    Quantum mechanics, the theory which rules the microworld of atoms and particles, certainly has the X factor. Unlike many other areas of physics, it is bizarre and counter-intuitive, which makes it dazzling and intriguing. When the 2022 Nobel prize in physics was awarded to Alain Aspect, John Clauser and Anton Zeilinger for research shedding light on quantum mechanics, it sparked excitement and discussion.

    But debates about quantum mechanics – be they on chat forums, in the media or in science fiction – can often get muddled thanks to a number of persistent myths and misconceptions. Here are four.

    1. A cat can be dead and alive

    Erwin Schrödinger could probably never have predicted that his thought experiment, Schrödinger’s cat, would attain internet meme status in the 21st century.

    It suggests that an unlucky feline stuck in a box with a kill switch triggered by a random quantum event – radioactive decay, for example – could be alive and dead at the same time, as long as we don’t open the box to check.

    We’ve long known that quantum particles can be in two states – for example in two locations – at the same time. We call this a superposition.

    Scientists have been able to show this in the famous double-slit experiment, where a single quantum particle, such as a photon or electron, can go through two different slits in a wall simultaneously. How do we know that?

    In quantum physics, each particle’s state is also a wave. But when we send a stream of photons – one by one – through the slits, it creates a pattern of two waves interfering with each other on a screen behind the slit. As each photon didn’t have any other photons to interfere with when it went through the slits, it means it must simultaneously have gone through both slits – interfering with itself (image below).

    2
    Interference pattern. grayjay

    For this to work, however, the states (waves) in the superposition of the particle going through both slits need to be “coherent” – having a well defined relationship with each other.

    These superposition experiments can be done with objects of ever increasing size and complexity. One famous experiment by Anton Zeilinger in 1999 demonstrated quantum superposition with large molecules of Carbon-60 known as “buckyballs”.

    So what does this mean for our poor cat? Is it really both alive and dead as long as we don’t open the box? Obviously, a cat is nothing like an individual photon in a controlled lab environment, it is much bigger and more complex. Any coherence that the trillions upon trillions of atoms that make up the cat might have with each other is extremely shortlived.

    This does not mean that quantum coherence is impossible in biological systems, just that it generally won’t apply to big creatures such as cats or a human.

    2. Simple analogies can explain entanglement

    Entanglement is a quantum property which links two different particles so that if you measure one, you automatically and instantly know the state of the other – no matter how far apart they are.

    Common explanations for it typically involve everyday objects from our classical macroscopic world, such as dice, cards or even pairs of odd-colored socks. For example, imagine you tell your friend you have placed a blue card in one envelope and an orange card in another. If your friend takes away and opens one of the envelopes and finds the blue card, they will know you have the orange card.

    But to understand quantum mechanics, you have to imagine the two cards inside the envelopes are in a joint superposition, meaning they are both orange and blue at the same time (specifically orange/blue and blue/orange). Opening one envelope reveals one colour determined at random. But opening the second still always reveals the opposite colour because it is “spookily” linked to the first card.

    One could force the cards to appear in a different set of colours, akin to doing another type of measurement. We could open an envelope asking the question: “Are you a green or a red card?”. The answer would again be random: green or red. But crucially, if the cards were entangled, the other card would still always yield the opposite outcome when asked the same question.

    Albert Einstein attempted to explain this with classical intuition, suggesting the cards could have been provided with a hidden, internal instruction set which told them in what colour to appear given a certain question. He also rejected the apparent “spooky” action between the cards that seemingly allows them to instantly influence each other, which would mean communication faster than the speed of light, something forbidden by Einstein’s theories.

    However, Einstein’s explanation was subsequently ruled out by Bell’s theorem (a theoretical test created by the physicist John Stewart Bell) and experiments by 2022’s Nobel laureates. The idea that measuring one entangled card changes the state of the other is not true. Quantum particles are just mysteriously correlated in ways we can’t describe with everyday logic or language – they don’t communicate while also containing a hidden code, as Einstein had thought. So forget about everyday objects when you think about entanglement.

    3. Nature is unreal and ‘non-local’

    Bell’s theorem is often said to prove that nature isn’t “local”, that an object isn’t just directly influenced by its immediate surroundings. Another common interpretation is that it implies properties of quantum objects aren’t “real”, that they do not exist prior to measurement.

    But Bell’s theorem only allows us to say that quantum physics means nature isn’t both real and local if we assume a few other things at the same time. These assumptions include the idea that measurements only have a single outcome (and not multiple, perhaps in parallel worlds), that cause and effect flow forward in time and that we do not live in a “clockwork universe” in which everything has been predetermined since the dawn of time.

    2
    Entanglement concept. Jurik Peter/Shuttestock.

    Despite Bell’s theorem, nature may well be real and local, if you allowed for breaking some other things we consider common sense, such as time moving forward. And further research will hopefully narrow down the great number of potential interpretations of quantum mechanics. However, most options on the table — for example, time flowing backwards, or the absence of free will — are at least as absurd as giving up on the concept of local reality.

    4. Nobody understands quantum mechanics

    A classic quote (attributed to physicist Richard Feynman, but in this form also paraphrasing Niels Bohr) surmises: “If you think you understand quantum mechanics, you don’t understand it.”

    This view is widely held in public. Quantum physics is supposedly impossible to understand, including by physicists. But from a 21st-century perspective, quantum physics is neither mathematically nor conceptually particularly difficult for scientists. We understand it extremely well, to a point where we can predict quantum phenomena with high precision, simulate highly complex quantum systems and even start to build quantum computers.

    Superposition and entanglement, when explained in the language of quantum information, requires no more than high-school mathematics. Bell’s theorem doesn’t require any quantum physics at all. It can be derived in a few lines using probability theory and linear algebra.

    Where the true difficulty lies, perhaps, is in how to reconcile quantum physics with our intuitive reality. Not having all the answers won’t stop us from making further progress with quantum technology. We can simply just shut up and calculate.

    Fortunately for humanity, Nobel winners Aspect, Clauser, and Zeilinger refused to shut up and kept asking why. Others like them may one day help reconcile quantum weirdness with our experience of reality.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation (AU) launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.

    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 9:01 pm on October 11, 2022 Permalink | Reply
    Tags: "Climate tipping points could lock in unstoppable changes to the planet – how close are they?", , , , The Conversation (AU)   

    From “The Conversation (AU)” : “Climate tipping points could lock in unstoppable changes to the planet – how close are they?” 

    From “The Conversation (AU)”

    10.6.22
    David Armstrong McKay

    “Continued greenhouse gas emissions risk triggering climate tipping points. These are self-sustaining shifts in the climate system that would lock-in devastating changes, like sea-level rise, even if all emissions ended.

    The first major assessment in 2008 [PNAS] identified nine parts of the climate system that are sensitive to tipping, including ice sheets, ocean currents and major forests. Since then, huge advances in climate modelling and a flood of new observations and records of ancient climate change have given scientists a far better picture of these tipping elements. Extra ones have also been proposed, like permafrost around the Arctic (permanently frozen ground that could unleash more carbon if thawed).

    Estimates of the warming levels at which these elements could tip have fallen since 2008. The collapse of the west Antarctic ice sheet was once thought to be a risk when warming reached 3°C-5°C above Earth’s pre-industrial average temperature. Now it’s thought to be possible at current warming levels [Nature (below)].

    In our new assessment [Science] of the past 15 years of research, myself and colleagues found that we can’t rule out five tipping points being triggered right now when global warming stands at roughly 1.2°C. Four of these five become more likely as global warming exceeds 1.5°C.

    These are sobering conclusions. Not all of the news coverage captured the nuance of our study, though. So here’s what our findings actually mean.

    Uncertain thresholds

    We synthesized the results of more than 200 studies to estimate warming thresholds for each tipping element. The best estimate was either one that multiple studies converged on or which a study judged to be particularly reliable reported. For example, records of when ice sheets had retreated in the past and modelling studies indicate the Greenland ice sheet is likely to collapse beyond 1.5°C. We also estimated the minimum and maximum thresholds at which collapse is possible: model estimates for Greenland range between 0.8°C and 3.0°C.

    2
    Greenland’s ice sheet is showing signs of destabilizing at current warming levels. David Dennis/Shutterstock.

    Within this range, tipping becomes more likely as warming increases. We defined tipping as possible (but not yet likely) when warming is above the minimum but below the best estimate, and likely above the best estimate. We also judged how confident we are with each estimate. For example, we are more confident in our estimates for Greenland’s ice sheet collapse than those for abrupt permafrost thaw.

    This uncertainty means that we do not expect four climate tipping points to be triggered the first year global temperatures reach 1.5°C (which climate scientists suggest is possible in the next five years), or even when temperatures averaged over several years reach 1.5°C sometime in the next couple of decades. Instead, every fraction of a degree makes tipping more likely, but we can’t be sure exactly when tipping becomes inevitable.

    This is especially true for the Greenland and west Antarctic ice sheets. While our assessment suggests their collapse becomes likely beyond 1.5°C, ice sheets are so massive that they change very slowly. Collapse would take thousands of years, and the processes driving it require warming to remain beyond the threshold for several decades. If warming returned below the threshold before tipping kicked in, it may be possible for ice sheets to temporarily overshoot their thresholds without collapsing.

    For some other tipping points, change is likely to be more dispersed. We estimate that both tropical coral reef death and abrupt permafrost thaw are possible at the current warming level. But thresholds vary between reefs and patches of permafrost. Both are already happening [Nature (below)] in some places, but in our assessment, these changes become much more widespread at a similar time beyond 1.5°C.

    Elsewhere, small patches of the Amazon and northern forests might tip and transition to a savannah-like state first, bypassing a more catastrophic dieback across the whole forest. Model results that are yet to be published suggest that Amazon tipping might occur in several regions at varying warming levels rather than as one big event.

    3
    The Amazon may not collapse from forest to grassland all at once. Paralaxis/Shutterstock.

    There may also be no well-defined threshold for some tipping elements. Ancient climate records suggest ocean currents in the North Atlantic can dramatically flip from being strong, as they are now, to weak as a result of both warming and melting freshwater from Greenland disrupting circulation. Recent modelling suggests that the threshold for the collapse of Atlantic circulation depends on how fast warming increases alongside other hard-to-measure factors, making it highly uncertain.

    Into the danger zone

    There are signs that some tipping points are already approaching. Degradation and drought have caused parts of the Amazon to become less resilient to disturbances like fire and emit more carbon [Nature] than they absorb.

    The front edge of some retreating west Antarctic glaciers are only kilometres away from the unstoppable retreat. Early warning signals in climate monitoring data (such as bigger and longer swings in how much glaciers melt each year) suggest that parts of the Greenland ice sheet and Atlantic circulation are also destabilizing.

    These signals can’t tell us exactly how close we are to tipping points, only that destabilization is underway and a tipping point may be approaching. The most we can be sure of is that every fraction of further warming will destabilize these tipping elements more and make the initiation of self-sustaining changes more likely.

    This strengthens the case for ambitious emissions cuts in line with the Paris agreement’s aim of halting warming at 1.5°C. This would reduce the chances of triggering multiple climate tipping points – even if we can’t rule out some being reached soon.”

    Science papers:
    Nature
    Science
    Nature
    Nature
    See the science papers for detailed material with images.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation (AU) launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.

    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 8:32 am on October 3, 2022 Permalink | Reply
    Tags: "‘Sad and distressing’:: massive numbers of bird deaths in Australian heatwaves reveal a profound loss is looming", , , The Conversation (AU)   

    From CSIRO (AU)-Commonwealth Scientific and Industrial Research Organization Via “The Conversation (AU)” : “‘Sad and distressing’:: massive numbers of bird deaths in Australian heatwaves reveal a profound loss is looming” 

    CSIRO bloc

    From CSIRO (AU)-Commonwealth Scientific and Industrial Research Organization

    Via

    “The Conversation (AU)”

    9.28.22
    Janet Gardner
    Adjunct Research Scientist, CSIRO

    Suzanne Prober
    Senior Principal Research Scientist, CSIRO

    5
    Credit: Shutterstock.

    1
    A Jacky Winter at the study site showing signs of dehydration on the morning following a 47℃ day. Author provided.

    2
    Lead author Janet Gardner with two Jacky Winter birds, during research for the study. Author provided.

    Heatwaves linked to climate change have already led to mass deaths of birds and other wildlife around the world. To stem the loss of biodiversity as the climate warms, we need to better understand how birds respond.

    The new study [Global Ecology and Biogeography (below]] set out to fill this knowledge gap by examining Australian birds. Alarmingly, we found birds at our study sites died at a rate three times greater during a very hot summer compared to a mild summer.

    And the news gets worse. Under a pessimistic emissions scenario, just 11% of birds at the sites would survive.

    The findings have profound implications for our bird life in a warming world – and underscore the urgent need to both reduce greenhouse gas emissions, and help animals find cool places to shelter.

    Feeling the heat

    The study examined native birds in two parts of semi-arid New South Wales: Weddin Mountains National Park near Grenfell and Charcoal Tank Nature Reserve near West Wyalong. At both locations, citizen scientists have been catching, marking and releasing birds regularly since 1986.

    This has produced data for 22,000 individual birds spanning 37 species. They include honeyeaters, thornbills, fairy-wrens, whistlers, treecreepers, finches and doves.

    Data from the past 30-odd years showed cold winters led only to a relatively small drop in survival rates. But it was a far starker picture in summer.

    3
    Sadly, many birds at the study site died on hot days. Author provided.

    During a mild summer with no days above 38℃, 86% of the birds survived. But in a hot summer with 30 days above 38℃, just 59% survived.

    We then used these real-life findings to model future survival, to the end of the century, for birds at our study sites.

    Worryingly, climate projections for the sites we studied show the number of days above 38℃ will at least double by the end of the century (or the year 2104). Meanwhile, days below 0℃ will disappear during this time.

    These projections are broadly similar for all arid and semi-arid regions across Australia.

    As winters warm, we predict bird survival in winter would increase slightly by the end of this century. But this would not offset the many more birds killed by extreme heat as summers warm.

    But to what extent will populations decline? To answer this question, we considered an optimistic scenario of rapid emissions reduction – resulting in about 1℃ warming compared to pre-industrial levels. Under this scenario, we predict annual survival will fall by one-third, from 63% to 43%.

    Under a pessimistic scenario, involving very little emissions reduction and 3.7℃ warming this century, the survival rate falls to a shocking 11%.

    Other lab-based studies around the world have made similar projections for bird populations. But our projections are unusual because they’re based on actual survival rates in wild populations measured over decades.

    What happens to birds in heatwaves?

    Some birds do manage to survive extreme heat. We then wondered: how does a bird protect itself from soaring temperatures? And can its habitat offer life-saving shelter?

    We addressed these questions in a complementary study led by zoologist Lynda Sharpe. It involved comparing the behaviour of individual birds on mild and hot days.

    We chose as our subject the Jacky Winter, a small robin common across Australia. Between 2018 and 2021 we followed the fates of 40 breeding pairs living in semi-arid mallee woodland in South Australia. There, the annual number of days above 42℃ has more than doubled over the past 25 years.

    As heat escalated, Jacky Winters showed a broad range of behavioural responses. This included adjusting their posture, activity levels and habitat use to avoid gaining heat and to increase heat dissipation.

    As air temperatures approached 35℃, birds moved to the top of the highest trees where greater wind speeds cooled their bodies. The birds also began to pant, which can lead to fatal dehydration.

    Once air temperatures climbed above 40℃, exceeding the birds’ body temperature, they moved to the ground to shelter in tree-base hollows and crevices. They remained in these “thermal refuges” for as long as it took for air temperatures to drop to about 38℃ – sometimes for up to eight hours. But this made foraging impossible and the birds lost body mass.

    We then examined what parts of the birds’ habitat offered the coolest place to shelter on extremely hot days. Hollows in tree bases were significantly cooler than all other locations we measured. The best of these cool hollows were rare and found only in the largest eucalypt mallees.

    Even with their flexible behaviour, the ability of Jacky Winters to survive heatwaves was finite – and apparently dependent on whether large trees were available. Some 29% percent of adults we studied disappeared (and were presumed dead) within 24 hours of air temperatures reaching a record-breaking 49℃ in 2019.

    Similarly, during two months of heatwaves in 2018, 20% of adults studied were lost, compared with only 6% in the two months prior.

    Eggs and nestlings were even more susceptible to heat. All 41 egg clutches and 21 broods exposed to air temperatures above 42℃ died.

    We found it distressing to witness such losses among birds we had followed for months and years. And it was deeply sad to see the breeding failures after the parent birds had invested so much effort in caring for eggs and tending to young.

    5
    A dead chick in a nest, identified in the study. Eggs and nestlings were especially susceptible to heat. Author provided.

    We need to act

    Our studies show extremely high temperatures are already killing troubling numbers of birds in Australia’s arid and semi-arid regions. These regions comprise 70% of the Australian continent and 40% of the global landmass.

    Such losses will only worsen as climate change escalates. This has profound implications for biodiversity in Australia and more broadly.

    Obviously, humanity must urgently reduce greenhouse gas emissions to limit global warming. But we must also better manage our biodiversity as the climate changes.

    Key to this is identifying and protecting thermal refuges such as tree hollows by, for example, managing fire to reduce the loss of large trees.

    Science paper:
    Global Ecology and Biogeography

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    CSIRO campus

    CSIRO (AU)-Commonwealth Scientific and Industrial Research Organization, is Australia’s national science agency and one of the largest and most diverse research agencies in the world.

    CSIRO works with leading organizations around the world. From its headquarters in Canberra, CSIRO maintains more than 50 sites across Australia and in France, Chile and the United States, employing about 5,500 people.

    Federally funded scientific research began in Australia 104 years ago. The Advisory Council of Science and Industry was established in 1916 but was hampered by insufficient available finance. In 1926 the research effort was reinvigorated by establishment of the Council for Scientific and Industrial Research (CSIR), which strengthened national science leadership and increased research funding. CSIR grew rapidly and achieved significant early successes. In 1949 further legislated changes included renaming the organization as CSIRO.

    Notable developments by CSIRO have included the invention of atomic absorption spectroscopy; essential components of Wi-Fi technology; development of the first commercially successful polymer banknote; the invention of the insect repellent in Aerogard and the introduction of a series of biological controls into Australia, such as the introduction of myxomatosis and rabbit calicivirus for the control of rabbit populations.

    Research and focus areas

    Research Business Units

    As at 2019, CSIRO’s research areas are identified as “Impact science” and organized into the following Business Units:

    Agriculture and Food
    Health and Biosecurity
    Data 61
    Energy
    Land and Water
    Manufacturing
    Mineral Resources
    Oceans and Atmosphere

    National Facilities
    CSIRO manages national research facilities and scientific infrastructure on behalf of the nation to assist with the delivery of research. The national facilities and specialized laboratories are available to both international and Australian users from industry and research. As at 2019, the following National Facilities are listed:

    Australian Animal Health Laboratory (AAHL)
    Australia Telescope National Facility – radio telescopes included in the Facility include the Australia Telescope Compact Array, the Parkes Observatory, Mopra Radio Telescope Observatory and the Australian Square Kilometre Array Pathfinder.

    STCA CSIRO Australia Compact Array (AU), six radio telescopes at the Paul Wild Observatory, is an array of six 22-m antennas located about twenty five kilometres (16 mi) west of the town of Narrabri in Australia.

    CSIRO-Commonwealth Scientific and Industrial Research Organization (AU) Parkes Observatory [Murriyang, the traditional Indigenous name], located 20 kilometres north of the town of Parkes, New South Wales, Australia, 414.80m above sea level.

    NASA Canberra Deep Space Communication Complex, AU, Deep Space Network. Credit: NASA.

    CSIRO Canberra campus.

    ESA DSA 1, hosts a 35-metre deep-space antenna with transmission and reception in both S- and X-band and is located 140 kilometres north of Perth, Western Australia, near the town of New Norcia.

    CSIRO-Commonwealth Scientific and Industrial Research Organisation (AU) CSIRO R/V Investigator.

    UK Space NovaSAR-1 satellite (UK) synthetic aperture radar satellite.

    CSIRO Pawsey Supercomputing Centre AU)

    Magnus Cray XC40 supercomputer at Pawsey Supercomputer Centre Perth Australia.

    Galaxy Cray XC30 Series Supercomputer at at Pawsey Supercomputer Centre Perth Australia.

    Pausey Supercomputer CSIRO Zeus SGI Linux cluster.

    Others not shown

    SKA

    SKA- Square Kilometer Array.

    SKA Square Kilometre Array low frequency at Murchison Widefield Array, Boolardy station in outback Western Australia on the traditional lands of the Wajarri peoples.

    EDGES telescope in a radio quiet zone at the Murchison Radio-astronomy Observatory in Western Australia, on the traditional lands of the Wajarri peoples.

     
  • richardmitnick 11:46 am on September 19, 2022 Permalink | Reply
    Tags: "Super-Earths are bigger and more common and more habitable than Earth itself – and astronomers are discovering more of the billions they think are out there", , Based on current projections about a third of all exoplanets are super-Earths., , Most super-Earths orbit cool dwarf stars which are lower in mass and live much longer than the Sun., , The Conversation (AU)   

    From “The Conversation (AU)” : “Super-Earths are bigger and more common and more habitable than Earth itself – and astronomers are discovering more of the billions they think are out there” 

    From “The Conversation (AU)”

    9.19.22
    Chris Impey
    University Distinguished Professor of Astronomy
    University of Arizona

    1
    Astronomers think the most likely place to find life in the galaxy is on super-Earths, like Kepler-69c, seen in this artist’s rendering. NASA Ames/JPL-CalTech.

    “Astronomers now routinely discover planets orbiting stars outside of the solar system – they’re called exoplanets. But in summer 2022, teams working on NASA’s Transiting Exoplanet Survey Satellite found a few particularly interesting planets orbiting in the habitable zones of their parent stars.

    One planet is 30% larger than Earth and orbits its star in less than three days. The other is 70% larger than the Earth and might host a deep ocean. These two exoplanets are super-Earths – more massive than the Earth but smaller than ice giants like Uranus and Neptune.

    I’m a professor of astronomy who studies galactic cores, distant galaxies, astrobiology and exoplanets. I closely follow the search for planets that might host life.

    Earth is still the only place in the universe scientists know to be home to life. It would seem logical to focus the search for life on Earth clones – planets with properties close to Earth’s. But research has shown that the best chance astronomers have of finding life on another planet is likely to be on a super-Earth similar to the ones found recently.

    2
    A super-Earth is any rocky planet that is bigger than Earth and smaller than Neptune. Credit: Aldaron, CC BY-SA.

    Common and easy to find

    Most super-Earths orbit cool dwarf stars which are lower in mass and live much longer than the Sun. There are hundreds of cool dwarf stars for every star like the Sun, and scientists have found super-Earths orbiting 40% of cool dwarfs they have looked at. Using that number, astronomers estimate that there are tens of billions of super-Earths in habitable zones where liquid water can exist in the Milky Way alone. Since all life on Earth uses water, water is thought to be critical for habitability.

    Based on current projections about a third of all exoplanets are super-Earths, making them the most common type of exoplanet in the Milky Way. The nearest is only six light-years away from Earth. You might even say that our solar system is unusual since it does not have a planet with a mass between that of Earth and Neptune.

    2
    Most exoplanets are discovered by looking for how they dim the light coming from their parent stars, so bigger planets are easier to find. Credit: Nikola Smolenski, CC BY-SA.

    Another reason super-Earths are ideal targets in the search for life is that they’re much easier to detect and study than Earth-sized planets. There are two methods astronomers use to detect exoplanets. One looks for the gravitational effect of a planet on its parent star and the other looks for brief dimming of a star’s light as the planet passes in front of it. Both of these detection methods are easier with a bigger planet.

    Super-Earths are super habitable

    Over 300 years ago, German philosopher Gottfried Wilhelm Leibniz argued that Earth was the “best of all possible worlds.” Leibniz’s argument was meant to address the question of why evil exists, but modern astrobiologists have explored a similar question by asking what makes a planet hospitable to life. It turns out that Earth is not the best of all possible worlds.

    Due to Earth’s tectonic activity and changes in the brightness of the Sun, the climate has veered over time from ocean-boiling hot to planet wide, deep-freeze cold. Earth has been uninhabitable for humans and other larger creatures for most of its 4.5-billion-year history. Simulations suggest the long-term habitability of Earth was not inevitable [Communications Earth & Environment (below)], but was a matter of chance. Humans are literally lucky to be alive.

    Researchers have come up with a list of the attributes that make a planet very conducive to life. Larger planets are more likely to be geologically active, a feature that scientists think would promote biological evolution. So the most habitable planet would have roughly twice the mass of the Earth and be between 20% and 30% larger by volume. It would also have oceans that are shallow enough for light to stimulate life all the way to the seafloor and an average temperature of 77 degrees Fahrenheit (25 degrees Celsius). It would have an atmosphere thicker than the Earth’s that would act as an insulating blanket. Finally, such a planet would orbit a star older than the Sun to give life longer to develop, and it would have a strong magnetic field that protects against cosmic radiation. Scientists think that these attributes combined will make a planet super habitable.

    By definition, super-Earths have many of the attributes of a super habitable planet. To date, astronomers have discovered two dozen super-Earth exoplanets that are, if not the best of all possible worlds, theoretically more habitable than Earth.

    Recently, there’s been an exciting addition to the inventory of habitable planets. Astronomers have started discovering exoplanets that have been ejected from their star systems, and there could be billions of them roaming the Milky Way. If a super-Earth is ejected from its star system and has a dense atmosphere and watery surface, it could sustain life for tens of billions of years, far longer than life on Earth could persist before the Sun dies.

    4
    One of the newly discovered super-Earths, TOI-1452b, might be covered in a deep ocean and could be conducive to life. Credit: Benoit Gougeon, Université de Montréal, CC BY-ND.

    Detecting life on super-Earths

    To detect life on distant exoplanets, astronomers will look for biosignatures, byproducts of biology that are detectable in a planet’s atmosphere.

    NASA’s James Webb Space Telescope was designed before astronomers had discovered exoplanets, so the telescope is not optimized for exoplanet research. But it is able to do some of this science and is scheduled to target two potentially habitable super-Earths in its first year of operations. Another set of super-Earths with massive oceans discovered in the past few years, as well as the planets discovered this summer, are also compelling targets for James Webb.

    But the best chances for finding signs of life in exoplanet atmospheres will come with the next generation of giant, ground-based telescopes: the 39-meter Extremely Large Telescope, the Thirty Meter Telescope and the 24.5-meter Giant Magellan Telescope. These telescopes are all under construction and set to start collecting data by the end of the decade.

    Astronomers know that the ingredients for life are out there, but habitable does not mean inhabited. Until researchers find evidence of life elsewhere, it’s possible that life on Earth was a unique accident. While there are many reasons why a habitable world would not have signs of life, if, over the coming years, astronomers look at these super habitable super-Earths and find nothing, humanity may be forced to conclude that the universe is a lonely place.”

    Science paper:
    Communications Earth & Environment

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Conversation (AU) launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.
    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 9:01 am on August 27, 2022 Permalink | Reply
    Tags: , "Our atom-moving laser sculpts matter into weird new shapes – new research", , , , The Conversation (AU)   

    From “The Conversation (AU)” : “Our atom-moving laser sculpts matter into weird new shapes – new research” 

    From “The Conversation (AU)”

    8.24.22
    Grant Henderson
    PhD candidate in Physics,
    University of Strathclyde

    Alison Yao
    Senior Lecturer of Physics
    University of Strathclyde

    1
    MENALABA/Flickr, CC BY-ND

    Getting atoms to do what you want isn’t easy – but it’s at the heart of a lot of groundbreaking research in physics.

    Creating and controlling the behavior of new forms of matter is of particular interest, and an active area of research. Our new study, published in Physical Review Letters [below], has uncovered a brand new way of sculpting ultra-cold atoms into different shapes using laser light.

    Ultracold atoms, cooled to temperatures close to absolute zero (-273°C), are of great interest to researchers as they allow them to see and explore physical phenomena that would otherwise be impossible. At these temperatures, cooler than outer space, groups of atoms form a new state of matter (not solid, liquid or gas) known as Bose–Einstein condensates (BEC). In 2001, physicists were awarded the Nobel prize for generating such a condensate.

    The defining feature of a BEC is that its atoms behave very differently to what we normally expect. Instead of acting as independent particles, they all have the same (very low) energy and are coordinated with each other.

    This is similar to the difference between photons (light particles) coming from the Sun, which may have many different wavelengths (energies) and oscillate independently, and those in laser beams, which all have the same wavelength and oscillate together.

    In this new state of matter, the atoms act much more like a single, wave-like structure than a group of individual particles. Researchers have been able to demonstrate wave-like interference patterns between two different BECs and even produce moving “BEC droplets”. The latter can be thought of as the atomic equivalent of a laser beam [Physica Scripta (below)].

    Moving droplets

    In our latest study, performed with our colleagues Gordon Robb and Gian-Luca Oppo, we investigated how specially shaped laser beams can be used to manipulate ultracold atoms of a BEC. The idea of using light to move objects is not new: when light falls on an object it can exert a (very small) force. This radiation pressure is the principle behind the idea of solar sails, where the force exerted by sunlight on large mirrors can be used to propel a spacecraft through space.

    In this study, however, we used a particular type of light that is capable of not just “pushing” the atoms, but also rotating them around, a bit like an “optical spanner”. These laser beams look like bright rings (or doughnuts) rather than spots and they have a twisted (helical) wavefront, as shown in the image below.

    1
    Light carrying orbital angular momentum (OAM, m) ‘twists’ as it moves. Author provided.

    Under the correct conditions, when such twisted light is shone on to a moving BEC the atoms in it are first attracted towards the bright ring before being rotated around it. As the atoms rotate, both light and atoms start to form droplets which orbit the original direction of the laser beam before being ejected outwards, away from the ring.

    The number of droplets is equal to twice the number of light twists. By changing the number, or direction, of the twists in the initial laser beam, we had full control over the number of droplets that formed, and the speed and direction of their subsequent rotation (see the image below). We could even prevent the atomic droplets from escaping from the ring so that they continued to orbit for much longer, producing a form of ultracold atomic current.

    2
    Twisted light shines on to a moving BEC, sculpting it into a ring before breaking it into a number of BEC droplets that orbit the direction of the light before breaking free and twisting away. Author provided.

    Ultracold atomic currents

    This approach of shining twisted light through ultracold atoms opens a new and simple way of controlling and sculpting matter into further unconventional and complex shapes.

    One of the most exciting potential applications of BECs is the generation of “atomtronic circuits”, where matter waves of ultracold atoms are guided and manipulated by optical and/or magnetic fields to form advanced equivalents of electronic circuits and devices such as transistors and diodes. Being able to reliably manipulate a BEC’s shape will ultimately help create atomtronic circuits.

    Our ultracold atoms, acting here like an “atomtronic superconducting quantum interference device” [Nano Letters (below)], have the potential to provide far superior devices than conventional electronics. That’s because neutral atoms result in less information loss than electrons which normally make up current. We also have the ability to change features of the device more easily.

    Most excitingly, however, is the fact that our method allows us the possibility to produce complex atomtronic circuits that would simply be impossible to design with normal materials. This could help design highly controllable and easily reconfigurable quantum sensors capable of measuring tiny magnetic fields that would otherwise be immeasurable. Such sensors would be useful in areas ranging from basic physics research to discovering new materials or measuring signals from the brain.

    Science papers:
    Physical Review Letters
    Physica Scripta 1996
    Nano Letters 2020

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    “The Conversation (AU)” launched as a pilot project in October 2014. It is an independent source of news and views from the academic and research community, delivered direct to the public.
    Our team of professional editors work with university and research institute experts to unlock their knowledge for use by the wider public.

    Access to independent, high quality, authenticated, explanatory journalism underpins a functioning democracy. Our aim is to promote better understanding of current affairs and complex issues. And hopefully allow for a better quality of public discourse and conversation.

     
  • richardmitnick 7:11 am on August 20, 2022 Permalink | Reply
    Tags: "Astronomers have detected one of the biggest black hole jets in the sky", , , , , NGC2663, The Conversation (AU),   

    From Western Sydney University (AU) Via “The Conversation (AU)” : “Astronomers have detected one of the biggest black hole jets in the sky” 

    From Western Sydney University (AU)

    Via

    “The Conversation (AU)”

    8.18.22
    Luke Barnes
    Lecturer in Physics, Western Sydney University

    Miroslav Filipovic
    Professor, Western Sydney University

    Ray Norris
    Professor, School of Science, Western Sydney University

    Velibor Velović
    PhD Candidate, Western Sydney University

    1
    Credit: Jurik Peter/Shutterstock.

    Astronomers at Western Sydney University have discovered one of the biggest black hole jets in the sky.

    Spanning more than a million light years from end to end, the jet shoots away from a black hole with enormous energy, and at almost the speed of light. But in the vast expanses of space between galaxies, it doesn’t always get its own way.

    Taking a closer look

    At a mere 93 million light-years away, the galaxy NGC2663 is in our neighborhood, cosmically speaking. If our galaxy were a house, NGC2663 would be a suburb or two away.

    Looking at its starlight with an ordinary telescope, we see the familiar oval shape of a “typical” elliptical galaxy, with about ten times as many stars as our own Milky Way.

    Typical, that is, until we observed NGC2663 with CSIRO’s Australian Square Kilometre Array Pathfinder (ASKAP) in Western Australia – a network of 36 linked radio dishes forming a single super-telescope.

    The radio waves reveal a jet of matter, shot out of the galaxy by a central black hole. This high-powered stream of material is about 50 times larger than the galaxy: if our eyes could see it in the night sky, it would be bigger than the Moon.

    While astronomers have found such jets before, the immense size (more than a million light years across) and relative closeness of NGC2663 make these some of the biggest known jets in the sky.

    Shock diamonds

    So, what did we see, when the precision and power of ASKAP got a “close-up” (astronomically speaking!) view of an extragalactic jet?

    This research is led by doctoral student Velibor Velović of Western Sydney University, and has been accepted for publication in the journal MNRAS [below]. Our Evolutionary Map of the Universe (EMU) survey sees evidence of the matter between galaxies pushing back on the sides of the jet.

    This process is analogous to an effect seen in jet engines. As the exhaust plume blasts through the atmosphere, it is pushed from the sides by the ambient pressure. This causes the jet to expand and contract, pulsing as it travels.

    As the image below shows, we see regular bright spots in the jet, known as “shock diamonds” because of their shape. As the flow compresses, it glows more brightly.

    2
    Black hole jets from NGC2663 compared to a jet engine. Top image: observations from the ASKAP radio telescope. Bottom: a methane rocket successfully being tested in the Mojave Desert. Note the patterns of compression ( Mike Massee/XCOR, used with permission, Author provided.

    Biggest one yet

    As well as in jet engines, shock diamonds have been seen in smaller, galaxy-sized jets. We’ve seen jets slam into dense clouds of gas, lighting them up as they bore through. But jets being constricted from the sides is a more subtle effect, making it harder to observe.

    However, until NGC2663, we’ve not seen this effect on such enormous scales.

    This tells us there is enough matter in the intergalactic space around NGC2663 to push against the sides of the jet. In turn, the jet heats and pressurizes the matter.

    This is a feedback loop: intergalactic matter feeds into a galaxy, galaxy makes black hole, black hole launches jet, jet slows supply of intergalactic matter into galaxies.

    These jets affect how gas forms into galaxies as the universe evolves. It’s exciting to see such a direct illustration of this interaction.

    The EMU survey, which is also responsible for identifying a new type of mysterious astronomical object called an “Odd Radio Circle”, is continuing to scan the sky.

    3
    The ghostly ORC1 (blue/green fuzz), on a backdrop of the galaxies at optical wavelengths. There’s an orange galaxy at the centre of the ORC, but we don’t know whether it’s part of the ORC, or just a chance coincidence. Image by Bärbel Koribalski, based on ASKAP data, with the optical image from the [Dark Energy Survey](https://www.darkenergysurvey.org), Author provided

    This remarkable radio jet will soon be joined by many more discoveries.

    As we do, we’ll build up a better understanding of how black holes intimately shape the galaxies forming around them.

    Science paper:
    MNRAS

    See the full article here.

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    Western Sydney University (AU), formerly the University of Western Sydney, is an Australian multi-campus university in the Greater Western region of Sydney, Australia. The university in its current form was founded in 1989 under the terms of the State Legislature “Western Sydney University Act 1997 No 116”, which created a federated network university with an amalgamation between the Nepean College of Advanced Education and the Hawkesbury Agricultural College. The Macarthur Institute of Higher Education was incorporated in the university in 1989. In 2001, the University of Western Sydney was restructured as a single multi-campus university rather than as a federation. In 2015, the university underwent a rebranding which resulted in a change in name from the University of Western Sydney to Western Sydney University. It is a provider of undergraduate, postgraduate, and higher research degrees with campuses in Bankstown, Blacktown, Campbelltown, Hawkesbury, Liverpool, Parramatta, and Penrith.

    In 2021, the QS World University Rankings ranks the university 474th in the world, coming 26th in Australia and 5th in Sydney. In 2021, it was ranked in the top 300 in the world and 18th in Australia in The Times Higher Education World University Rankings.

     
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