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  • richardmitnick 9:04 am on March 7, 2019 Permalink | Reply
    Tags: , , , , , COSMOS, ,   

    From COSMOS Magazine: “Mechanics of coronal mass ejections revealed” 

    Cosmos Magazine bloc

    From COSMOS Magazine

    07 March 2019
    Lauren Fuge

    A coronal mass ejection captured by NASA’s Solar Dynamics Observatory in September, 2017. NASA/SDO.


    An international team of astronomers has untangled new insight into the birth of coronal mass ejections, the most massive and destructive explosions from the sun.

    In a paper published in the journal Science Advances, a team led by Tingyu Gou from the University of Science and Technology of China was able to clearly observe the onset and evolution of a major solar eruption for the first time.

    From a distance the sun seems benevolent and life-giving, but on closer inspection it is seething with powerful fury. Its outer layer – the corona – is a hot and wildly energetic place that constantly sends out streams of charged particles in great gusts of solar wind.

    It also emits localised flashes known as flares, as well as enormous explosions of billions of tons of magnetised plasma called coronal mass ejections (CMEs).

    These eruptions could potentially have a big effect on Earth. CMEs can damage satellite electronics, kill astronauts on space walks, and cause magnetic storms that can disrupt electricity grids.

    Studying CMEs is key to improving the capability to forecast them, and yet, for decades, their origin and evolution have remained elusive.

    “The underlying physics is a disruption of the coronal magnetic field,” explains Bernhard Kliem, co-author on the paper, from the University of Potsdam in Germany.

    Such a disruption allows an expanding bubble of plasma – a CME – to build up, driving it and the magnetic field upwards. The “bubble” can tear off and erupt, often accompanied by solar flares.

    The magnetic field lines then fall back and combine with neighbouring lines to form a less-stressed field, creating the beautiful loops seen in many UV and X-ray images of the sun.

    “This breaking and re-closing process is called magnetic reconnection, and it is of great interest in plasma physics, astrophysics, and space physics,” says Kliem.

    NASA Magnetic reconnection, Credit: M. Aschwanden et al. (LMSAL), TRACE, NASA

    NASA TRACE spacecraft (1998-2010)

    But the reason why the coronal magnetic field is disturbed at all is a matter of continuing debate.

    “To many, an instability of the magnetic field is the primary reason,” says Kliem. “This requires the magnetic field to form a twisted flux tube, known as magnetic flux rope, where the energy to be released in the eruption can be stored.”

    The theory holds that turbulence causes the magnetic flux ropes to become tangled and unstable, and if they suddenly rearrange themselves in the process of magnetic reconnection, they can release the trapped energy and trigger a CME.

    Others in the field think that it’s the other way around – magnetic reconnection is the trigger that forms the flux rope in the first place.

    It’s a tricky question to tease out because flux ropes and reconnection are so intertwined. Recent studies [Nature] even suggest that there’s another layer of complexity: smaller magnetic loops called mini flux ropes, or plasmoids, which continuously form in a fractal-like fashion and may have a cascading influence on bigger events like a CME.

    To get a better handle on this complex process, the team observed the evolution of a CME that erupted on May 13, 2013. By combining multi-wavelength data from NASA’s Solar Dynamics Observatory (SDO) with modern analysis techniques, they were able to determine the correct sequence of events: that a magnetic reconnection in the solar corona formed the flux rope, which then became unstable and erupted.

    Specifically, they found that the CME bubble continuously evolved from mini flux ropes, bridging the gap between micro- and macro-scale dynamics and thus illuminating a complete evolutionary path of CMEs.

    The next step, Kliem says, is to understand another important phenomenon in the eruption process: a thin, elongated structure known as a “current sheet”, in which the mini flux ropes were formed.

    “We need to study when and where the coronal magnetic field forms such current sheets that can build up a flux rope, which then, in turn, can erupt to drive a solar eruption,” he concludes.

    See the full article here .

    Please help promote STEM in your local schools.

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  • richardmitnick 11:12 am on January 9, 2019 Permalink | Reply
    Tags: , , , , COSMOS, , Galaxy clusters much more common than thought   

    From COSMOS Magazine: “Galaxy clusters much more common than thought” 

    Cosmos Magazine bloc

    From COSMOS Magazine

    09 January 2019
    Andrew Masterson

    Data mining exercise reveals a whole new class of astronomical structure.

    The MACS J0717 galaxy cluster, 5.6 billion light years from Earth, as seen by NASA’s Chandra X-ray Observatory.
    X-ray: NASA/CXC/SAO/van Weeren et al.; Optical: NASA/STScI; Radio: NSF/NRAO/VLA

    NASA/Chandra X-ray Telescope

    NRAO/Karl V Jansky Expanded Very Large Array, on the Plains of San Agustin fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m)

    A re-examination of data gathered a decade ago by astronomers using a 3.9-metre telescope [AAO Anglo Australian Telescope]located at the Siding Spring Observatory in the Australian state of New South Wales has revealed that the number of galaxy clusters in the universe has been underestimated by as much as a third.

    AAO Anglo Australian Telescope near Siding Spring, New South Wales, Australia, Altitude 1,100 m (3,600 ft)

    The finding is remarkable, because galaxy clusters – collections of individual galaxies bound together by gravity – are the largest structures in the universe and, by dint of containing billions or trillions of stars, relatively easy to see.

    The word “relatively”, in this case, is particularly apt, because stars, and whatever planets and other rocky bits and bobs accompany them, comprise only a very small fraction of any cluster’s mass.

    This was a discovery first made by American astronomer Fritz Zwicky in 1933, when he analysed the movements of stars within an enormous agglomeration called the COMA cluster and concluded that the mass of all the visible matter therein was insufficient to account for his findings. Something else – and something huge, at that – must have been in play.

    Fritz Zwicky discovered Dark Matter when observing the movement of the Coma Cluster.

    Fritz Zwicky from http:// palomarskies.blogspot.com

    Coma cluster via NASA/ESA Hubble

    But most of the real work was done by Vera Rubin a Woman in STEM

    Astronomer Vera Rubin at the Lowell Observatory in 1965, worked on Dark Matter (The Carnegie Institution for Science)

    Vera Rubin measuring spectra, worked on Dark Matter (Emilio Segre Visual Archives AIP SPL)

    Vera Rubin, with Department of Terrestrial Magnetism (DTM) image tube spectrograph attached to the Kitt Peak 84-inch telescope, 1970. https://home.dtm.ciw.edu

    Dark Matter Research

    Universe map Sloan Digital Sky Survey (SDSS) 2dF Galaxy Redshift Survey

    Scientists studying the cosmic microwave background hope to learn about more than just how the universe grew—it could also offer insight into dark matter, dark energy and the mass of the neutrino.

    Dark matter cosmic web and the large-scale structure it forms The Millenium Simulation, V. Springel et al

    Dark Matter Particle Explorer China

    DEAP Dark Matter detector, The DEAP-3600, suspended in the SNOLAB deep in Sudbury’s Creighton Mine

    LUX Dark matter Experiment at SURF, Lead, SD, USA

    ADMX Axion Dark Matter Experiment, U Uashington

    And thus, the concept of dark matter entered the cosmological discourse.

    Current estimates suggest that in most galaxy clusters, the galaxies themselves – at least as defined by visible matter – comprise only 1% of the total mass. Hot gas clouds account for another 9%, and dark matter makes up the remaining 90%.

    The latest research, however, led by Luis Campusano from the Universidad de Chile, in Chile, suggests that in a substantial tranche of cases these percentages need to be revised, with the visible matter component declining even further.

    Campusano and colleagues revisited data gathered during a major galaxy redshift survey known as 2dFGRS, which was completed in 2003. The project looked at 191,440 galaxies.

    By carefully mining the information, and discarding some standard definitions, the astronomers identified 341 clusters – 87 of them previously unknown.

    The newly discovered groups, classified by the researchers as “late-type-rich clusters”, are described as being “high mass-to-light ratio systems”, which means that they contain fewer stars than other clusters. The stars are also less densely packed, meaning the galaxies contained in each cluster are less luminous than normal.

    Campusano and colleagues looked only at galaxies contained in the nearby universe – another highly relative term – but assume the results probably hold for the rest of the cosmos.

    The discovery – published in The Astrophysical Journal – seems likely to prompt a surge in newly focussed practical and theoretical astronomy. Not only are galaxy clusters about 33% more common than previously assumed, the astronomers report, but the newly defined “class of late-type-rich clusters is not predicted by current theory”.

    See the full article here .

    Please help promote STEM in your local schools.

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  • richardmitnick 12:36 pm on November 28, 2018 Permalink | Reply
    Tags: , COSMOS, , , Hints of a ‘sterile’ neutrino, ,   

    From FNAL via COSMOS Magazine: “Hints of a ‘sterile’ neutrino” 

    FNAL II photo

    FNAL Art Image
    FNAL Art Image by Angela Gonzales

    From Fermi National Accelerator Lab , an enduring source of strength for the US contribution to scientific research world wide.

    Cosmos Magazine bloc

    COSMOS Magazine

    Curious result could point to flaws in the Standard Model of particle physics.

    Standard Model of Elementary Particles

    Something missing? The Standard Model admits three types of neutrino. New evidences suggest a fourth might also exist. generalfmv/Getty Images

    Scientists may have caught a glimpse of a new breed of particle from an unseen side of the universe.

    Researchers conducting an exercise known as the Mini Booster Neutrino Experiment (MiniBooNE) at Fermilab near Chicago in the US have painstakingly compiled measurements of neutrinos over the last 15 years.


    The experiment has yielded only the three types of neutrinos described in the Standard model: electron neutrinos, muon neutrinos and tau neutrinos. But now the scientists have published a paper in the journal Physical Review Letters, reporting a possible trace of a fourth.

    Neutrinos are subatomic particles less than a million times lighter than electrons. They are one of the three components of matter, along with electrons and quarks, which make up the nuclei in atoms. Each component has two heavier counterparts, which decay after fractions of seconds: this array of particles in threes is known as the Standard Model.

    A fourth particle that bucks the threefold pattern could be big news says MiniBooNE spokesman Rex Tayloe, from Indiana University in the United States.

    “If that is the correct explanation of the signal, it is an important and far-reaching result as it opens up the field of particle physics to a new set of particles – beyond the current Standard Model,” he says.

    Neutrinos are already the most mysterious particle in the Standard Model. They are preposterously numerous – 100 million neutrinos pass through the human body every second, barely interacting.

    And because they interact so weakly, only a tiny number are ever detected. Their mass is still uncertain. It is so small that for a long time it was thought to be zero.

    Unlike quarks and electrons, which decay from unstable, heavy forms into lighter, stable ones, neutrinos continually change form, slipping between the three forms as they as they torpedo through space at close to the speed of light.

    It is this shape-changing that MiniBooNE has been studying, using a 541-metre beam of neutrinos. The scientists create them by smashing high-energy protons into a target of the metal beryllium, which creates unstable particles called pions that quickly decay, creating neutrinos.

    The process creates a type called muon neutrinos, which are directed to MiniBooNE’s detector, a 12.2-metre sphere filled with 818 tonnes of pure mineral oil, lined with 1520 photomultipliers that catch tiny flashes of light caused by the occasional neutrino interaction.

    The Standard Model predicts a small percentage of muon neutrinos will change into electron neutrinos in the half-kilometre flight. But MiniBooNE found more of these than expected.

    One possible explanation for this rapid oscillation is a fourth neutrino form – but because it has never been detected it must not even interact in the incredibly weak way that the other three forms do. The scientists term it a sterile neutrino.

    The hint of a new, invisible particle raises scientists’ hopes for a whole new family that could help solve puzzles of dark matter, dark energy and the imbalance of matter and antimatter in the universe.

    But the isuue is far from resolved. While MiniBooNE’s result is line with an experiment in the nineties at Los Alamos in New Mexico in the US, other experiments have failed to confirm the same effect, which has physicists scratching their heads.

    Solutions could be found by new larger experiments that are coming online, such as DUNE, which tracks neutrinos over a 1300-kilometre path under the US.

    SURF DUNE LBNF Caverns at Sanford Lab

    FNAL LBNF/DUNE from FNAL to SURF, Lead, South Dakota, USA

    There is also the huge Japanese detector Hyper-Kamiokande, and a larger scale version of MiniBooNE.

    Hyper-Kamiokande, a neutrino physics laboratory located underground in the Mozumi Mine of the Kamioka Mining and Smelting Co. near the Kamioka section of the city of Hida in Gifu Prefecture, Japan.

    It’s possible the new data will overturn the sterile neutrino theory as a systematic error of some sort. But even if so, given their history, the mysterious particles are still likely to have some surprises in store.

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 2:15 pm on November 21, 2018 Permalink | Reply
    Tags: a tadpole-shaped galaxy, , , , , COSMOS, Crippled and gigantic   

    From COSMOS Magazine: “Crippled and gigantic, a tadpole-shaped galaxy” 

    Cosmos Magazine bloc

    From COSMOS Magazine

    21 November 2018
    Andrew Masterson

    Deep in Hickson’s Local Group 98, a profoundly damaged galaxy persists. N. Brosch / Tel Aviv University

    A huge but profoundly damaged galaxy has been identified by a team of researchers from Israel, the US and Russia.

    The galaxy, which bears a passing resemblance to a tadpole, is more than 300 million light years away from Earth. It is described by lead researcher Noah Brosch, of the Florence and George Wise Observatory at Tel Aviv University as “disrupted”, because it has clearly been subjected to massive outside forces.

    Usually, disrupted galaxies are relatively small – a result of their stars being either incorporated into a nearby more massive galaxy, or being ejected en masse into space as a result of a titanic collision between two star systems.

    The latest find, however, will very likely prompt a re-examination of the constraints for the survival of such systems.

    “We have found a giant, exceptional relic of a disrupted galaxy,” says Brosch.

    The structure, which is inside a cluster of smaller galaxies called Hickson’s Compact Group 98, is enormous. At approximately one million light-years long from end to end, it is 10 times the size of the Milky Way.

    “What makes this object extraordinary is that the tail alone is almost 500,000 light-years long,” says co-author Michael Rich of the University of California, Los Angeles.

    “If it were at the distance of the Andromeda galaxy, which is about 2.5 million light years from Earth, it would reach a fifth of the way to our own Milky Way.”

    Brosch and his colleagues suggest that the galactic tadpole formed as the result of a previous invisible star-filled dwarf galaxy being ripped apart by the gravitational force of two larger galaxies, and its components being dramatically redistributed.

    “The extragalactic tadpole contains a system of two very close ‘normal’ disc galaxies, each about 40,000 light-years across,” says Brosch. “Together with other nearby galaxies, the galaxies form a compact group.”

    That group, the scientists stay, is far from a settled system. All the members of Hickson’s Compact Group 98 are expected to merge into a single giant galaxy in about one billion years – at which time, presumably, the extragalactic tadpole will turn into a cosmic frog.

    The research is published in the Monthly Notices of the Royal Astronomical Society.

    See the full article here .

    Please help promote STEM in your local schools.

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  • richardmitnick 5:44 pm on October 29, 2018 Permalink | Reply
    Tags: , , , , , COSMOS,   

    From COSMOS Magazine: “Signs of mergers may help us prove supermassive black holes exist” 

    Cosmos Magazine bloc

    From COSMOS Magazine

    28 October 2018
    Martin Krause

    Black holes with masses billions of times that of the sun have long been theorised. Now, research takes astronomy closer to proving the contention.

    Visible light image of the radio galaxy Hercules A obtained by the Hubble Space Telescope superposed with a radio image taken by the Very Large Array of radio telescopes in New Mexico, USA. NASA

    NASA/ESA Hubble Telescope

    NRAO/Karl V Jansky Expanded Very Large Array, on the Plains of San Agustin fifty miles west of Socorro, NM, USA, at an elevation of 6970 ft (2124 m)

    Observations of nature tend to throw up unexpected results and new mysteries – whether you’re investigating the rain forest or outer space. When radio astronomy took off in the 1950s, we had no idea that it would lead to the discovery that galaxies including our own seem to have terrifyingly large black holes at their centre – millions to billions of times the mass of the sun.

    A few decades later, we still haven’t been able to prove that these beasts – dubbed supermassive black holes – actually exist. But our new research, published in the Monthly Notices of the Royal Astronomical Society, could one day help us do so.

    Early radio astronomers discovered that some galaxies emit radio waves (a type of electromagnetic radiation). They knew that galaxies sometimes collide and merge, and naturally wondered whether this could have something to do with the radio emission. Better observations, however, refuted this idea over the years.

    They also discovered that the radio waves were emitted as narrow jets, meaning that the power came from a tiny region in the nucleus. The radio power was indeed huge – often surpassing the luminosity of all the stars in the galaxy taken together. Various suggestions were made as to how such a huge amount of energy could be produced, and it was in the 1970s that scientists finally proposed [Astronomy and Astrophysics] that a supermassive black hole could be the culprit. The objects are nowadays known as quasars.

    Women in STEM – Dame Susan Jocelyn Bell Burnell

    Dame Susan Jocelyn Bell Burnell, discovered pulsars with radio astronomy. Jocelyn Bell at the Mullard Radio Astronomy Observatory, Cambridge University, taken for the Daily Herald newspaper in 1968. Denied the Nobel.

    Dame Susan Jocelyn Bell Burnell 2009

    Dame Susan Jocelyn Bell Burnell (1943 – ), still working from http://www. famousirishscientists.weebly.com

    Theoretical models estimated that these objects would have a mass of an entire small galaxy concentrated in a space comparable to Earth’s orbit around the sun. But because only some galaxies produce energetic outbursts, it was unclear how common supermassive black holes would be. With the advent of the Hubble Space Telescope in 1990, the centres of nearby galaxies that did not emit radio bursts could finally be investigated. Did they contain supermassive black holes too?

    It turned out that many did – astronomers saw signs of gravitating masses influencing the matter around it without emitting any light. Even the Milky Way showed evidence of having a supermassive black hole at the centre, now known as Sgr A*.

    Sgr A* from ESO VLT

    SgrA* NASA/Chandra

    SGR A* , the supermassive black hole at the center of the Milky Way. NASA’s Chandra X-Ray Observatory

    At this point, astronomers became increasingly convinced that supermassive black holes were a reality and could plausibly explain the extreme energetic outbursts from some galaxies.

    However, there is no definitive proof yet. That is despite the fact that some supermassive black holes emit jets – these come from the surroundings of the black hole rather than the black hole itself. So how do you prove the existence of something completely dark? A black hole as defined by Einstein’s theory of general relativity is a region of space bounded by a horizon – a surface from inside of which no light or material object can ever escape. So, it’s a pretty difficult task for astronomers: they need to see something that emits nothing.

    For smaller black holes the size of a stellar mass, a proof was indeed found: when two such objects merge, they emit gravitational waves, a tiny wobbling of space that was for the first time registered in 2015. The detection proved that black holes exist, that they sometimes form pairs and that they indeed merge. This was a tremendous success, honoured with the Nobel prize in 2017.

    We also have a good understanding of where normal sized black holes come from – they are what is left after a star much more massive than the sun has arrived at the end of its lifetime. But both the existence and the origin of supermassive black holes are shrouded in mystery.

    Spinning black holes

    We have now found indications that many of the radio jets produced by supermassive black holes may in fact be the result of these objects forming pairs, orbiting each other. We did this by comparing the observed radio maps of their regions with our computer models.

    The presence of a second black hole would make the jets produced by the first one change direction in a periodic way over hundreds of thousands of years. We realised that the cyclic change in jet direction would cause a very specific appearance in radio maps of the galaxy centre.

    Lobes are created by the jets depositing energy to surrounding particles. Author provided.

    We found evidence of such a pattern in about 75% of our sample of “radio galaxies” (galaxies that emit radio waves), suggesting that supermassive black hole pairs are the rule, not the exception. Such pairs are actually expected to form after galaxies merge. Each galaxy contains a supermassive black hole, and since they are heavier than all the individual stars, they sink to the centre of the newly formed galaxy where they first form a close pair and then merge under emission of gravitational waves.

    While our observation provides an important piece of evidence for the existence of pairs of supermassive black holes, it’s not a proof either. What we observe are still the effects that the black holes somehow cause indirectly. Just like with normal black holes, a full proof of the existence of supermassive black hole pairs requires detection of gravitational waves emitted by them.

    Current gravitational wave telescopes can only detect gravitational waves from stellar mass black holes.

    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation

    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project

    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger

    Skymap showing how adding Virgo to LIGO helps in reducing the size of the source-likely region in the sky. (Credit: Giuseppe Greco (Virgo Urbino group)

    The reason is that they orbit around one another much faster, which leads to the production of higher frequency gravitational waves that we can detect. The next generation of instruments will however be able to register low frequency gravitational waves as well – potentially from supermassive black hole pairs.

    ESA/eLISA the future of gravitational wave research

    This would finally prove their existence – half a century after they were first proposed. It’s an exciting time to be a scientist.

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 10:29 am on October 25, 2018 Permalink | Reply
    Tags: , , , COSMOS, NASA ANITA balloon, Similar to the light blue glow of Chernekov light emitted in water surrounding nuclear reactors, Something energetic has travelled through the planet – a phenomenon that is just not allowed within the Standard Model of particle physics, The Askaryan effect, UHECRs- ultra-high energy cosmogenic neutrinos   

    From University of Hawaii via COSMOS: ““Upside down” cosmic rays may be new particle” 

    U Hawaii

    From University of Hawaii


    25 October 2018
    Alan Duffy

    In the vastness of Antarctica, two subatomic particles are challenging the standard model. Credit: Joseph Van Os/Getty Images

    A handful of particles erupting from the ice of Antarctica may well be the first indication of a new particle of nature.

    Each and every second your body is struck by hundreds of cosmic rays, particles that are created from some of the most energetic events in the known universe, such as exploding stars or accreting blackholes.

    Cosmic rays, as the name suggests, are of cosmic origin and tend to strike the ground from space. Yet NASA’s Antarctic Impulsive Transient Antenna (ANITA) – an array of radio antennas dangling from a balloon 37 metres above the ground – has spotted particles emanating from the ground. This suggests that something energetic has travelled through the planet – a phenomenon that is just not allowed within the Standard Model of particle physics.

    NASA ANITA balloon to detect cosmic ray showers and will monitor 32 potential gaseous contaminants, including formaldehyde, ammonia and carbon monoxide,

    NASA ANITA balloon team

    NASA ANITA balloon carrries scientific instruments above will detect cosmic ray showers

    The intriguing findings are reported in the journal Physical Review Letters, by a team led by Peter Gorham from the University of Hawaii, in the US.

    ANITA’s a balloon circumnavigates Antarctica, detecting cosmic ray showers, in particular ultra-high energy cosmogenic neutrinos (UHECRs), as they collide with ice below.

    The system detects these collisions by the emission of radio waves from the burst of secondary particles generated as the neutrinos move in the ice more quickly than light.

    This process is known as the Askaryan effect, and is similar to the light blue glow of Chernekov light emitted in water surrounding nuclear reactors.

    In its first flight ANITA detected 16 such events, showing the power of this technique to detect the otherwise ghost-like neutrinos. The radio waves reflected back towards the balloon became horizontally polarised – in much the same way that light becomes horizontally polarised when it reflects off a puddle.

    Surprisingly, hidden in the first run of data, a single UHECR was detected from below the horizon from the ice, but without any polarisation from reflection. This was noted at the time, but the evidence wasn’t strong enough to rule out the particle being produced in the ice itself.

    In the third flight of ANITA another 20 UHECRs were detected – and again a single event was detected from the ice without the reflected polarisation.

    The two events now suggest that high energy particles have travelled all the way through the earth, creating a burst of Askaryan radio waves in the ice, like upside-down cosmic rays.

    While standard neutrinos are famously non-interacting, capable of flying through light years of solid lead, their high energy counterparts have a much greater cross-section, or chance, of collision. In fact, the UHECRs spotted by ANITA can’t possibly have travelled through the earth without collision, at least according to the Standard Model of particle physics.

    Possible solutions include interactions beyond the Standard Model, or even an entirely new particle, such as a sterile neutrino. More such detections are required to confirm any such claims but for now these tentative signals are exciting hints of a new era of physics.

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    System Overview

    The University of Hawai‘i System includes 10 campuses and dozens of educational, training and research centers across the Hawaiian Islands. As the public system of higher education in Hawai‘i, UH offers opportunities as unique and diverse as our Island home.

    The 10 UH campuses and educational centers on six Hawaiian Islands provide unique opportunities for both learning and recreation.

    UH is the State’s leading engine for economic growth and diversification, stimulating the local economy with jobs, research and skilled workers.

  • richardmitnick 1:27 pm on October 24, 2018 Permalink | Reply
    Tags: Biermann battery effect, COSMOS, , , ,   

    From COSMOS Magazine: “Supercomputer finds clues to violent magnetic events” 

    Cosmos Magazine bloc

    From COSMOS Magazine

    24 October 2018
    Phil Dooley

    An aurora over Iceland, the product of sudden magnetic reconnection. Credit Natthawat/Getty Images

    Researchers are a step closer to understanding the violent magnetic events that cause the storms on the sun’s surface and fling clouds of hot gas out into space, thanks to colossal computer simulations at Princeton University in the US.

    The disruptions in the magnetic field, known as magnetic reconnections, are common in the universe – the same process causes the aurora in high latitude skies – but existing models are unable to explain how they happen so quickly.

    A team led by Jackson Matteucci decided to investigate by building a full three-dimensional simulation of the ejected hot gas, something that required enormous computing power. The results are published in the journal Physical Review Letters.

    The researchers modelled more than 200 million particles using Titan, the biggest supercomputer [no longer true, the writer should have known that] in the US.

    ORNL Cray Titan XK7 Supercomputer, once the fastest in the world.

    They discovered that a three-dimensional interaction called the Biermann battery effect was at the heart of the sudden reconnection process.

    Discovered in the fifties by German astrophysicist Ludwig Biermann, the Biermann battery effect shows how magnetic fields can be generated in charged gases, known as plasma.

    In such plasmas, if a region develops in which there is a temperature gradient at right angles to a density gradient, a magnetic field is created that encircles it.

    Astrophysicists propose that this effect might take place in interstellar plasma clouds, such as nebulae, and generate the cosmic magnetic fields that we see throughout the universe.

    In contrast with the huge scale of cosmic plasma clouds, magnetic reconnection happens at a scale of microns when two magnetic fields collide, says Matteucci.

    He likens the process to collisions between two sizable handfuls of rubber bands. In stable circumstances the magnetic field lines are loops, like the bands. But sometimes turbulence in the plasma pushes these band analogues together so forcefully that they sever and reconnect to different ones, thus forming loops at different orientations.

    Some of the new loops are stretched taut and snap back, providing the energy that ejects material so violently, and causes magnetic storms or glowing auroras.

    The Princeton simulation showed that as the fields collide there is a sudden spike in the temperature in a very localised region, which sets off the Biermann battery effect, suddenly creating a new magnetic field in the midst of the collision. It’s this newly-appearing field that severs the lines and allows them to reconfigure.

    Although Matteucci’s simulations are for tiny plasma clouds generated by lasers hitting foil, he says they could help us understand large-scale processes in the atmosphere.

    “If you do a back of the envelope calculation, you find it could play an important role in reconnection in the magnetosphere, where the solar wind collides with the Earth’s magnetic field,” he says.

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

  • richardmitnick 1:27 pm on October 17, 2018 Permalink | Reply
    Tags: , , , , COSMOS, from Euclid to LIGO, , , The Australian International Gravitational Research Centre   

    From The Australian International Gravitational Research Centre via COSMOS: “A short [?] history of spacetime from Euclid to LIGO” 

    From The Australian International Gravitational Research Centre



    17 October 2018
    David Blair

    A year ago today, the world learned that a huge team of scientists around the world had confirmed the existence of gravitational waves, the long history of discovery that led to breakthrough.

    The discovery of gravitational waves marked an important step on a never-ending journey of discovery regarding the nature of the universe.
    sakkmesterke/Getty Images

    In 2015 we first heard the whooping sound made by a pair of colliding black holes. Two years later it was the unique chirp made by a pair of colliding neutron stars. Our newfound ability to eavesdrop on cataclysmic events at the far reaches of the universe is thanks to a new generation of gravitational wave detectors. The gravitational sound show is just beginning, and it promises to reveal the nature of spacetime as never before.

    The quest to understand space

    What is space? We know thinkers have pondered that question at least for as long as there are recorded texts. The clay tablets left by Ancient Babylonians show they were toying with the nature of triangles.

    But, 2300 years ago, the Greek mathematician Euclid revolutionised the science of geometry with systematic thinking that captured the descriptive work of the past and elevated it to the level of universal truths or axioms.

    His 13-volume treatise Elements uncovered the perfection of lines and shapes and put it all together in the most influential science book of all time, in print for 2000 years and published in 1000 editions. It is still taught in schools today.

    But are Euclid’s axioms truly universal?

    In the early 1800s, German mathematician and physicist Carl Gauss was the first to challenge Euclid’s laws of geometry, especially his fifth axiom, which states that parallel lines can never meet.

    Gauss observed that on curved surfaces, parallel lines – such as longitude lines at the earth’s equator – intersect at the poles. He also realised that space could have shape, and his Egregium Theorem showed that you could measure its shape if you measured distances and angles.

    Imagine you’re an ant living on a balloon; your world would seem flat. But an ant familiar with the Egregium Theorem would stretch strings and draw triangles. If the angles of the triangle added up to more than 180 degrees, the ant would know it’s living on curved space.

    Egregium, by the way, is Latin for “exceptional”.

    Gauss’ determination to put Euclid’s theorems to the test set the scene for Einstein.

    By 1905, he had already come up with his theory of Special Relativity. This was the theory that gave us E=Mc2, which means that energy has mass and mass has energy.

    In 1907 Einstein had another revelation that he later described as “the happiest thought of my life”. He realised that gravity is indistinguishable from acceleration. If you’re riding an elevator with your bathroom scales, you’ll find you’re lighter as the elevator accelerates down and heavier when it decelerates. So, Einstein realised, gravity is the force you feel when you prevent free fall.

    It took eight more years and help from his friends for him to combine this happy thought with Gauss’s thinking about the shape of space, to create his final theory of gravity: General Relativity. Published in 1915, it was based on the revolutionary idea that mass and energy deform space and time, and that deformed spacetime itself has energy. In a certain sense spacetime is an elastic material: immensely stiff but deformable – like a trampoline.

    Einstein’s publication gave rise to a succession of remarkable discoveries.

    Within months, while serving in the German army, physicist and astronomer Karl Schwarzschild solved Einstein’s equations to reveal how the curvature of space and the warping of time depends on distance from a central mass. The closer the distance and the larger the mass, the more warping there is, and at a certain distance from a central point mass space and time actually come to an end.

    He was of course imagining a ‘black hole’, but it would take 50 years before the term was coined.

    A few months later, in 1916, Einstein found a solution to his own equations. It predicted the existence of gravitational waves, ripples in spacetime that would travel at the speed of light.

    And in the following years, discoveries provided support for the notion that space was a deformable elastic medium – one that could propagate gravitational waves.

    In 1919, English physicist Sir Arthur Eddington’s observation of an eclipse from the island of Principe near West Africa proved that space is curved by the Sun. In 1922 Russian scientist Alexander Friedmann showed that Einstein’s equations predicted a dynamic universe in which space itself must either expand or contract. And in 1929 American astronomer Edwin Hubble discovered that the universe was in fact expanding.

    When Einstein predicted gravitational waves in 1916 he realised that they could be generated by pair of stars circling each other. He came up with a formula that describes how gravitational wave power depends on their masses, the speeds and the spacing – all measurable numbers.

    But there was a catch: in his formula, the wave power was divided by an enormous number, a crazy number, that I call Einstein’s number. Algebraically, Einstein’s number is c5/G – the speed of light multiplied by itself five times, divided by G, the tiny number that tells us the weakness of gravity.

    Put together, c5/G is more than 1054. If you divide anything by a number this vast, you get next to nothing. Einstein realised this. Nothing he could conceive of could possibly produce measurable gravitational waves. The waves were of academic interest only, he concluded.

    What Einstein hadn’t been aware of was that Schwarzschild, who died of an auto-immune disease in 1916, had left him a hidden treasure. The trouble was that Schwarzschild’s solution, which described a singularity where space and time cease to exist, was viewed by Einstein and others as a mathematical oddity, not a description of anything that could possibly be real.

    But 50 years on, black holes – as these singularities were later dubbed – were the best hypothesis to explain a strange x-ray emitting star called Cygnus X-1.

    A tiny object with vast gravity was needed to explain this powerful erratic x-ray emission. People began to think that black holes might be real.

    Then someone took Einstein’s 1916 equation for wave power, and substituted in Schwarzschild’s black hole formula. A school kid could have done it. The result was miraculous!

    With Schwarzschild’s formula, the division by Einstein’s number that made gravitational waves merely academic is transformed into a multiplication by the same number. Suddenly the wave power for a pair of black holes circling each other up-close becomes almost as big as Einstein’s number itself.

    This is roughly the power of all the stars in the visible universe! The catch is it lasts for only an instant. This was Schwarzschild’s hidden treasure.

    Schwarzschild’s work tells us that when black holes collide they create a pure gravitational explosion, more powerful than a supernova or a gamma ray burst. Nothing beats it except the Big Bang itself.

    However, as an explosion of rippling space, it would pass freely through you. Even if it happened as nearby to Earth as the Sun, you would feel no more than a tiniest shudder. Yet each such gravitational explosion would in principle be detectable across the entire universe.

    Harnessing inertia to build a gravitational wave detector

    I was inspired to join the quest to detect colliding black holes by the eccentric pioneer of gravitational wave astronomy, American physicist Joseph Weber. Back then, we reasoned that explosions so vast must be detectable. We thought that if we worked hard at inventing a gravitational detector, we might pick up a signal by Christmas! That was in 1973.

    Our ability to detect gravitational waves relies on the concept of inertia – the tendency of matter to continue in its state of motion unless acted on by an external force.

    Scientists have been relying on inertia to detect relative motion for nearly 2000 years. In 132 AD, Chinese scientist Zhang Heng harnessed inertia to build the first seismometer.

    Inside a big bronze urn he suspended a mass so that it could swing freely in the horizontal plane. If the ground moved, so would the urn, but the mass, anchored to space by the law of inertia, would stay in place.

    Inside, the movement dislodged a ball from the mouth of one of eight dragons that marked the cardinal directions. The ball rolled out and was caught in the mouth of a bronze toad. This way he detected an earthquake hundreds of kilometres away.

    Heng’s seismometer allowed him to detect the motion of the earth against unchanging space. But what if space suddenly stretches? You won’t feel a thing, and nor will a seismometer, just as you do not feel the universe expanding. But, you might notice that a distant object has just moved away from you. It did this because inertia caused it to follow expanding space.

    Modern day gravitational wave detectors like the Laser Interferometer Gravitational-Wave Observatory (LIGO) in the US detect the stretching and shrinking of space caused by a passing wave by suspending two 40 kilogram masses four kilometres apart.

    These masses are coated with near-perfect mirrors, so changes in the distance between them can be measured by using a beam of laser light as a ruler. The catch is the minuscule size of the change. Like ripples in a pond, gravitational waves diminish as they expand away from the source.

    Even though LIGO was aiming to measure the space distortion created by colliding black holes – the biggest dynamic distortion possible – the ripples they create reduce to half every time you double the distance.

    By the time the wave reaches the Earth from a black hole collision a billion light years away, the stretching and shrinking of space in a LIGO detector has reduced to a hundredth of a billionth of a billionth of a metre – much smaller than the size of a proton.

    VIRGO Gravitational Wave interferometer, near Pisa, Italy

    Caltech/MIT Advanced aLigo Hanford, WA, USA installation

    Caltech/MIT Advanced aLigo detector installation Livingston, LA, USA

    Cornell SXS, the Simulating eXtreme Spacetimes (SXS) project

    Gravitational waves. Credit: MPI for Gravitational Physics/W.Benger

    ESA/eLISA the future of gravitational wave research

    Skymap showing how adding Virgo to LIGO helps in reducing the size of the source-likely region in the sky. (Credit: Giuseppe Greco (Virgo Urbino group)

    A dream fulfilled

    It took more than 40 years and several generations of detectors, before, finally, the pair of advanced LIGO detectors were ready to begin listening for the sounds of gravitational waves. The new detectors were three times more sensitive than previous ones, but still three times below their ultimate design specification. We were hopeful but not optimistic.

    On September 14, 2015, a few days before the official start date, the first signal came in. Was it a hoax? Was it accidental? A short rapidly rising pitch, from two octaves below to middle-C made a brief whoop sound. It was heard in two detectors 3000 kilometres apart and had a time delay just right for a wave travelling at the speed of light. After months of investigation there was no doubt that it was real.

    All our dreams were finally fulfilled on February 11, 2016, when gravitational wave astronomers announced in a Washington press conference, that they had indeed detected a pair of black holes spiralling together and merging into a single black hole.

    And since that first detection, more whoops from other colliding black holes have followed.

    You might think that detecting the collision of a pair black holes would be a hard act to follow. Yet a year and a half after that announcement, the world was again thrilling to the news of another type of cosmic cataclysm.

    We had not been optimistic about detecting colliding black holes because we had very little idea how many pairs of black holes might exist. Instead we had placed our hopes on something we knew much more about: neutron stars.

    Neutron stars are one step away from becoming a black hole. Many exist as pulsars: rapidly spinning remnants of supernova explosions that emit powerful flickering beams of radio waves. They have a dimeter of about 20 kilometres, are composed of neutrons, and are denser than an atomic nucleus.

    Thousands of them are known in the Milky Way, and the predictions were that out in the distant universe we might be able to detect one or two of them merging every year.

    Little did we know that we were already detecting those events.

    During the 1980s astronomers were puzzling over vast bursts of gamma rays being detected by orbiting gamma ray telescopes, on average one every day.

    In 1989 a paper published in Nature by Hebrew University physicist Tsvi Piran proposed these bursts were created by merging neutron stars, spiralling together at 10% of light speed, and flinging some of their nearly pure neutron matter out into space. Here it would go off like an enormous nuclear fission bomb, giving off bursts of gamma rays. The process would also be a forge for heavy elements in the universe like platinum and gold.

    Since the advanced LIGO detectors started working in 2015, our 1000-strong team comprising researchers based at more than 80 universities around the world were hoping for all of this: a long slow chirp of gravitational waves as a pair of neutron stars spiralled together, a burst of gamma rays produced when they collided, and an atomic explosion where we might see the signature of gold production.

    Most of us thought the chances of all of this was very small. The gamma ray beam might miss the earth. The explosion, called a macronova or kilonova, is much weaker than a supernova and would be hard to detect.

    However, more than 100 telescopes around the world had already signed up to receive alerts from the LIGO detectors on either side of the US, and the European Virgo detector in Pisa, Italy, in the event of a gravitational wave signal.

    On August 17, 2017, all of our Christmases came at once.

    It was exactly what we had dreamed of. The gravitational wave signal was loud and clear in the two LIGO detectors in the US, but very weak in the European Virgo detector because of its orientation.

    The non-detection by Virgo told us roughly where to look in the sky. The Fermi gamma ray observatory out in space detected a burst of gamma rays 1.7 seconds later, coming from the same region of sky. A few hours later the Swope telescope in Chile detected the fading glow of a vast explosion, in that same region, at the edge of a known galaxy, 130 million light years away.

    Before long 100 telescopes across the southern hemisphere were watching it. The colours in the light indicated the presence of heavy elements like gold and platinum.

    The future

    We called this the birth of multi-messenger astronomy: the gravity wave messenger and the electromagnetic messenger worked in unison. This discovery was a stupendous example of scientific prediction. It confirmed Einstein’s 102 year-old prediction that gravity waves travel at the speed of light, and Piran’s 28 year-old prediction that gamma ray bursts were the signature of colliding neutron stars, and that gold and platinum were formed in this explosion.

    Think about this: that gold on your finger is a fossil from the collision of two neutron stars.

    From these recent discoveries we can predict what lies ahead. As sensitivity improves, we’ll exponentially increase our reach into the universe. Increase the sensitivity by two and you’re reaching into a volume 23 times larger, which means eight times as many signals.

    In the next few years the world’s existing three detectors, plus two more under construction in Japan and India, should be tuning in to the sounds of hundreds of black hole and neutron stars collisions every year.

    More detectors will help to pinpoint the source of the signals, but the biggest pay-off comes from increasing sensitivity. Just a four-fold increase in sensitivity would expand our horizon to more than half of the visible universe. A 10-fold improvement would give us the whole universe! Detectors with this capability have been suggested for Australia, China, Europe and the USA.

    The legacy of Einstein, the recent Nobel Prize winners and the huge international LIGO and Virgo team, will be the ability to listen to the symphony of the universe. It will be in a minor key because the truth is that our universe is winding down as black holes form, grow and gobble up each other.

    But I can’t end on a melancholy note. Rather I want to sing in celebration of gravitational waves as humanity’s new set of ears. We are no longer deaf to the sounds of space. And we can be pretty certain that our cosmic ears will give us deeper understanding of the nature of space.

    We are still groping to understand its microstructure and its reason for being. Is it a quantum foam inhabited by strings, or is it something else?

    Stay tuned for surprises, unforeseen revelations, and an avalanche of discoveries as our remarkable new technology develops.

    An extra treat https://sciencesprings.wordpress.com/2017/10/20/from-ucsc-neutron-stars-gravitational-waves-and-all-the-gold-in-the-universe/

    See the full article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition

    The Australian International Gravitational Observatory (AIGO) Located at Gingin

    Welcome to the Australian International Gravitational Research Centre. The Australian International Gravitational Research Centre is based in the School of physics of the University of Western Australia (UWA) and is part of the Australian Consortium for Interferometric Gravitational Astronomy (ACIGA). It was established in 1990 to enable a cooperative research centre providing a national focus in a major frontier in physics: the detection of gravitational waves and the development of gravitational astronomy. Through strong national and international participation, the research centre concentrates on the development of advanced technologies driven by the goal of the next generation large scale gravitational observatory construction.

  • richardmitnick 11:53 am on October 17, 2018 Permalink | Reply
    Tags: Closing in on a giant ringed planet, COSMOS, Currently the existence of the exoplanet dubbed J1407b is only hypothetical, The mystery of an exoplanet with a ring system more than 100 times larger than the one that girdles Saturn will not be resolved until at least 2021 evidence suggests., The star J140747.93−394542.6,   

    From Universiteit Leiden via COSMOS: “Closing in on a giant ringed planet” 

    From Universiteit Leiden



    17 October 2018
    Andrew Masterson

    Century-old photographs aid in the hunt for a massive and elusive system observed just once in more than a century.

    An artist’s impression of the mystery exoplanet surrounded by a massive ring system. Credit Ron Miller

    The mystery of an exoplanet with a ring system more than 100 times larger than the one that girdles Saturn will not be resolved until at least 2021, evidence suggests.

    Currently, the existence of the exoplanet, dubbed J1407b, is only hypothetical – a speculative answer to the question of why in 2007 a star, J140747.93−394542.6, or J1407 for short, 460 light-years from Earth in the constellation of Centaurus, appeared to undergo “a series of symmetric, deep eclipsing events”.

    The ostensible eclipses – detected as a periodic dimming of the star’s light – occurred over a 52-day period. However, only one of them was observed in detail, limiting, thus, the amount of information that could be gleaned. A favoured, if tentative, explanation for the phenomenon was that light from J1407 was temporarily obscured (from the point of view of Earth observers) by an object surrounded by a vast array of rings.

    In 2012, American Association of Variable Star Observers (AAVSO) relayed a request from Eric Mamajek of the Cerro Tololo Interamerican Observatory in Chile for assistance in monitoring the star in the hope of seeing another fade-out.

    CTIO an astronomical observatory located on Cerro Tololo in the Coquimbo Region of northern Chile, with additional facilities located on Cerro Pachón about 10 kilometres (6.2 mi) to the southeast. Altitude 2,207 m (7,241 ft)

    The suggested “ringed companion”, wrote the AAVSO’s Elizabeth Waagen, was “likely to be a brown dwarf or giant planet” that “may constitute a moon-forming ‘protoexosatellite disk’.”

    Thus far, however, the world’s astronomers have come up with bupkis.

    Now Robin Mentel of Leiden University in the Netherlands has come up with at least partial evidence to explain why.

    In a paper published in the journal Astronomy and Astrophysics, he and colleagues detail a novel investigation that involved looking to the past in order to constrain possibilities in the future.

    Over a period of two years, Mentel studied historical photographic plates showing the star, comparing its brightness with that of other, known, nearby stars to see if any dimming – and thus a likely eclipse – could be seen.

    By the end of the investigation, 490 plates had been studied, the oldest dating to 1890.

    And the result? Once again, bupkis. In every shot, J1407 shone fine and bright, its intensity never wavering.

    This, however, Mentel and colleagues are quick to point out, does not mean that there wasn’t an eclipse in the 107 years between the earliest image being recorded and the 2007 dimming being observed – after all, the plate collection did not constitute a continuous, unbroken record – but it does make it possible to suggest how much time elapses between events.

    On that basis, Mentel suggests that the ringed planet – or ringed brown dwarf – will transit the star again in either 2021 and 2024.

    Providing, of course, that it exists at all. One thing, however, is sure: In three years, the hunt for the possible “protoexosatellite disk” will kick up a gear.

    See the full COSMOS article here.
    See the full Leiden article here .


    Please help promote STEM in your local schools.

    Stem Education Coalition


    Leiden University was founded in 1575 and is one of Europe’s leading international research universities. It has seven faculties in the arts, sciences and social sciences, spread over locations in Leiden and The Hague. The University has over 6,500 staff members and 26,900 students. The motto of the University is ‘Praesidium Libertatis’ – Bastion of Freedom.

  • richardmitnick 7:46 am on September 18, 2018 Permalink | Reply
    Tags: , , , Ceres’ lonely ice volcano is only one of many, , COSMOS,   

    From COSMOS Magazine: “Ceres’ lonely ice volcano is only one of many” 

    Cosmos Magazine bloc

    From COSMOS Magazine

    Bill Condie

    The mysterious mountain Ahuna Mons is seen in this mosaic of images from NASA’s Dawn spacecraft. Dawn took these images from its low-altitude mapping orbit, from an altitude of 385 kilometres in December 2015. Credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

    NASA Dawn Spacescraft

    The dwarf planet Ceres has had as many as 22 ice volcanoes, new research suggests.

    Images from NASA’s Dawn mission has revealed there is currently a single volcano, an icy peak known as Ahuna Mons.

    But research based on data from the mission suggests that new volcanoes have appeared around every 50 million years over the past billion. They erupt, build up and then sink back into the surface.

    The research, published in Nature Astronomy, suggests that Ahuna Mons is relatively young.

    “Ahuna Mons has an upper age limit of 240 million years derived from crater size,” the researchers, led by University of Arizona planetary scientists Michael Sori, write. “But it may be much younger because the mountain itself is too small and has too few craters to be reliably dated.”

    Ice volcanoes, or cryovolcanoes, leave less impact on the surface than volcanoes on planets such as Earth.

    A simulated perspective view of Ceres’ lonely mountain, Ahuna Mons. NASA/JPL-Caltech/UCLA/MPS/DLR/IDA

    Instead of molten rock, they erupt liquid or gaseous ammonia, water or methane.

    Traces of cryovolcanism have been found on several bodies in the outer Solar System. “Cryovolcanism may be an important planetary phenomenon in shaping the surfaces of many worlds in the outer Solar System and revealing their thermal histories,” the researchers say.

    “However, the physics, chemistry and ubiquity of this geologic process remain poorly understood, especially in comparison to the better-studied silicate volcanism on the terrestrial planets.”

    NASA’s Dawn spacecraft discovered Ahuna Mons while orbiting Ceres in 2015.

    Sori and colleagues used models of relaxing dome shapes to identify 22 former cryovolcanoes on Ceres in images taken by the Dawn mission. 

The authors also estimate that the total amount of icy material that has been erupted onto the surface of Ceres is one hundred to one hundred-thousand times less than the volumes of molten rock erupted on the Earth, Moon, Venus or Mars.

    Ceres was the first object discovered in the main asteroid belt when Italian astronomer Father Giuseppe Piazzi spotted the object in 1801. It was initially classified as a planet but later classified as an asteroid as more objects were found in the same region.

    In recognition of its planet-like qualities, Ceres was designated a dwarf planet in 2006 along with Pluto and Eris.

    See the full article here .

    Please help promote STEM in your local schools.

    Stem Education Coalition

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