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  • richardmitnick 5:36 pm on November 20, 2017 Permalink | Reply
    Tags: , , , , Messier 60,   

    From Universe Today: “Messier 60 – the NGC 4649 Galaxy” 


    Universe Today

    20 Nov , 2017
    Tammy Plotner

    Messier 60. Credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona

    U Arizona Mt Lemon Sky Center, in the Santa Catalina Mountains approximately 28 kilometers (17 mi) northeast of Tucson, Arizona (USA)

    Welcome back to Messier Monday! Today, we continue in our tribute to our dear friend, Tammy Plotner, by looking at the elliptical galaxy known as Messier 60.

    In the 18th century, while searching the night sky for comets, French astronomer Charles Messier kept noting the presence of fixed, diffuse objects he initially mistook for comets. In time, he would come to compile a list of approximately 100 of these objects, hoping to prevent other astronomers from making the same mistake. This list – known as the Messier Catalog – would go on to become one of the most influential catalogs of Deep Sky Objects.

    One of the notable objects in this catalog is Messier 60, an elliptical galaxy located approximately 55 million light-years away in the Virgo constellation. Measuring some 60,000 light years across, this galaxy is only about half as large as the Milky Way. However, it still manages to pack in an estimated 400 billion stars which, depending on which estimates you go by, is between four times and the same amount as our own.
    What You Are Looking At:

    Located about 60 million light years away and spanning about 120 million light years of space, M60 is the third brightest elliptical in the Virgo group and and is the dominant member of a subcluster of four galaxies, which is the closest-known isolated compact group of galaxies. In larger telescopes, you’ll see another nearby galaxy – NGC 4647 – which might first be taken for a interactor, but may very well lay at a different distance since there is no tidal evidence so far found.

    See the full article here .

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  • richardmitnick 5:13 pm on November 20, 2017 Permalink | Reply
    Tags: , , , , , Kepler Planets Tend to Have Siblings of the Same Size   

    From AAS NOVA: “Kepler Planets Tend to Have Siblings of the Same Size” 



    20 November 2017
    Susanna Kohler

    Artist’s impression of a Kepler multiplanet system. A new study has found that planets within the same system tend to share similar masses as well as radii. [NASA / JPL-Caltech]

    NASA/Kepler Telescope

    After 8.5 years of observations with the Kepler space observatory, we’ve discovered a large number of close-in, tightly-spaced, multiple-planet systems orbiting distant stars. In the process, we’ve learned a lot about the properties about these systems — and discovered some unexpected behavior. A new study explores one of the properties that has surprised us: planets of the same size tend to live together.

    Orbital architectures for 25 of the authors’ multiplanet systems. The dots are sized according to the planets’ relative radii and colored according to mass. Planets of similar sizes and masses tend to live together in the same system. [Millholland et al. 2017]

    Ordering of Systems

    From Kepler’s observations of extrasolar multiplanet systems, we have seen that the sizes of planets in a given system aren’t completely random. Systems that contain a large planet, for example, are more likely to contain additional large planets rather than additional planets of random size. So though there is a large spread in the radii we’ve observed for transiting exoplanets, the spread within any given multiplanet system tends to be much smaller.

    This odd behavior has led us to ask whether this clustering occurs not just for radius, but also for mass. Since the multiplanet systems discovered by Kepler most often contain super-Earths and mini-Neptunes, which have an extremely large spread in densities, the fact that two such planets have similar radii does not guarantee that they have similar masses.

    If planets don’t cluster in mass within a system, this would raise the question of why planets coordinate only their radii within a given system. If they do cluster in mass, it implies that planets within the same system tend to have similar densities, potentially allowing us to predict the sizes and masses of planets we might find in a given system.

    Insight into Masses

    Led by NSF graduate research fellow Sarah Millholland, a team of scientists at Yale University used recently determined masses for planets in 37 Kepler multiplanet systems to explore this question of whether exoplanets in a multiplanet system are more likely to have similar masses rather than random ones.

    Millholland and collaborators find that the masses do show the same clustering trend as radii in multiplanet systems — i.e., sibling planets in the same system tend to have both masses and radii that are more similar than if the system were randomly assembled from the total population of planets we’ve observed. Furthermore, the masses and radii tend to be ordered within a system when the planets are ranked by their periods.

    The host star’s metallicity is correlated with the median planetary radius for a system. [Adapted from Millholland et al. 2017]

    The authors note two important implications of these results:

    The scatter in the relation between mass and radius of observed exoplanets is primarily due to system-to-system variability, rather than the variability within each system.
    Knowing the properties of a star and its primordial protoplanetary disk might allow us to predict the outcome of the planet formation process for the system.

    Following up on the second point, the authors test whether certain properties of the host star correlate with properties of the planets. They find that the stellar mass and metallicity have a significant effect on the planet properties and the structure of the system.

    Continuing to explore multiplanet systems like these appears to be an excellent path forward for understanding the hidden order in the broad variety of exoplanets we’ve observed.


    Sarah Millholland et al 2017 ApJL 849 L33. doi:10.3847/2041-8213/aa9714

    Related Journal Articles
    See the full article for further references with links.

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    AAS Mission and Vision Statement

    The mission of the American Astronomical Society is to enhance and share humanity’s scientific understanding of the Universe.

    The Society, through its publications, disseminates and archives the results of astronomical research. The Society also communicates and explains our understanding of the universe to the public.
    The Society facilitates and strengthens the interactions among members through professional meetings and other means. The Society supports member divisions representing specialized research and astronomical interests.
    The Society represents the goals of its community of members to the nation and the world. The Society also works with other scientific and educational societies to promote the advancement of science.
    The Society, through its members, trains, mentors and supports the next generation of astronomers. The Society supports and promotes increased participation of historically underrepresented groups in astronomy.
    The Society assists its members to develop their skills in the fields of education and public outreach at all levels. The Society promotes broad interest in astronomy, which enhances science literacy and leads many to careers in science and engineering.

    Adopted June 7, 2009

  • richardmitnick 4:43 pm on November 20, 2017 Permalink | Reply
    Tags: , , , , ESO Observations Show First Interstellar Asteroid is Like Nothing Seen Before, , , , The interstellar asteroid 'Oumuamua   

    From ESO: “ESO Observations Show First Interstellar Asteroid is Like Nothing Seen Before” 

    ESO 50 Large

    European Southern Observatory

    20 November 2017
    Olivier Hainaut
    Garching, Germany
    Tel: +49 89 3200 6752

    Karen Meech
    Institute for Astronomy
    Honolulu, Hawai`i, USA
    Cell: +1-720-231-7048
    Email: meech@IfA.Hawaii.Edu

    Richard Hook
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591

    For the first time ever astronomers have studied an asteroid that has entered the Solar System from interstellar space. Observations from ESO’s Very Large Telescope in Chile and other observatories around the world show that this unique object was traveling through space for millions of years before its chance encounter with our star system. It appears to be a dark, reddish, highly-elongated rocky or high-metal-content object. The new results appear in the journal Nature on 20 November 2017.

    This very deep combined image shows the interstellar asteroid ‘Oumuamua at the centre of the picture. It is surrounded by the trails of faint stars that are smeared as the telescopes tracked the moving asteroid. This image was created by combining multiple images from ESO’s Very Large Telescope as well as the Gemini South Telescope. The object is marked with a blue circle and appears to be a point source, with no surrounding dust. Credit: ESO/K. Meech et al.

    Gemini South telescope, Cerro Tololo Inter-American Observatory (CTIO) campus near La Serena, Chile, at an altitude of 7200 feet

    This diagram shows the orbit of the interstellar asteroid ‘Oumuamua as it passes through the Solar System. Unlike all other asteroids and comets observed before, this body is not bound by gravity to the Sun. It has come from interstellar space and will return there after its brief encounter with our star system. Its hyperbolic orbit is highly inclined and it does not appear to have come close to any other Solar System body on its way in. Credit: ESO/K. Meech et al.

    This plot shows how the interstellar asteroid ‘Oumuamua varied in brightness during three days in October 2017. The large range of brightness — about a factor of ten (2.5 magnitudes) — is due to the very elongated shape of this unique object, which rotates every 7.3 hours. The different coloured dots represent measurements through different filters, covering the visible and near-infrared part of the spectrum. The dotted line shows the light curve expected if ‘Oumuamua were an ellipsoid with a 1:10 aspect ratio, the deviations from this line are probably due to irregularities in the object’s shape or surface albedo. Credit: ESO/K. Meech et al.

    For the first time ever astronomers have studied an asteroid that has entered the Solar System from interstellar space. Observations from ESO’s Very Large Telescope in Chile and other observatories around the world show that this unique object was travelling through space for millions of years before its chance encounter with our star system. It appears to be a dark, reddish, highly-elongated rocky or high-metal-content object. The video is available in 4K UHD. Credit: ESO

    This animation shows the path of the interstellar asteroid 1I/2017 (‘Oumuamua) through the Solar System. Observations with ESO’s Very Large Telescope and others have shown that this unique object is dark, reddish in colour and highly elongated. Credit:ESO, M. Kornmesser, L.Calcada. Music: Azul Cobalto

    On 19 October 2017, the Pan-STARRS 1 telescope in Hawai`i picked up a faint point of light moving across the sky.

    Pann-STARS telescope, U Hawaii, Mauna Kea, Hawaii, USA, 4,207 m (13,802 ft) above sea level

    It initially looked like a typical fast-moving small asteroid, but additional observations over the next couple of days allowed its orbit to be computed fairly accurately. The orbit calculations revealed beyond any doubt that this body did not originate from inside the Solar System, like all other asteroids or comets ever observed, but instead had come from interstellar space. Although originally classified as a comet, observations from ESO and elsewhere revealed no signs of cometary activity after it passed closest to the Sun in September 2017. The object was reclassified as an interstellar asteroid and named 1I/2017 U1 (‘Oumuamua) [1].

    “We had to act quickly,” explains team member Olivier Hainaut from ESO in Garching, Germany. “’Oumuamua had already passed its closest point to the Sun and was heading back into interstellar space.”

    ESO’s Very Large Telescope was immediately called into action to measure the object’s orbit, brightness and colour more accurately than smaller telescopes could achieve. Speed was vital as ‘Oumuamua was rapidly fading as it headed away from the Sun and past the Earth’s orbit, on its way out of the Solar System. There were more surprises to come.

    Combining the images from the FORS instrument on the VLT using four different filters with those of other large telescopes, the team of astronomers led by Karen Meech (Institute for Astronomy, Hawai`i, USA) found that ‘Oumuamua varies dramatically in brightness by a factor of ten as it spins on its axis every 7.3 hours.


    Karen Meech explains the significance: “This unusually large variation in brightness means that the object is highly elongated: about ten times as long as it is wide, with a complex, convoluted shape. We also found that it has a dark red colour, similar to objects in the outer Solar System, and confirmed that it is completely inert, without the faintest hint of dust around it.”

    These properties suggest that ‘Oumuamua is dense, possibly rocky or with high metal content, lacks significant amounts of water or ice, and that its surface is now dark and reddened due to the effects of irradiation from cosmic rays over millions of years. It is estimated to be at least 400 metres long.

    Preliminary orbital calculations suggested that the object had come from the approximate direction of the bright star Vega, in the northern constellation of Lyra. However, even travelling at a breakneck speed of about 95 000 kilometres/hour, it took so long for the interstellar object to make the journey to our Solar System that Vega was not near that position when the asteroid was there about 300 000 years ago. ‘Oumuamua may well have been wandering through the Milky Way, unattached to any star system, for hundreds of millions of years before its chance encounter with the Solar System.

    Astronomers estimate that an interstellar asteroid similar to ‘Oumuamua passes through the inner Solar System about once per year, but they are faint and hard to spot so have been missed until now. It is only recently that survey telescopes, such as Pan-STARRS, are powerful enough to have a chance to discover them.

    “We are continuing to observe this unique object,” concludes Olivier Hainaut, “and we hope to more accurately pin down where it came from and where it is going next on its tour of the galaxy. And now that we have found the first interstellar rock, we are getting ready for the next ones!”


    [1] The Pan-STARRS team’s proposal to name the interstellar objet was accepted by the International Astronomical Union, which is responsible for granting official names to bodies in the Solar System and beyond. The name is Hawaiian and more details are given here. The IAU also created a new class of objects for interstellar asteroids, with this object being the first to receive this designation. The correct forms for referring to this object are now: 1I, 1I/2017 U1, 1I/’Oumuamua and 1I/2017 U1 (‘Oumuamua). Note that the character before the O is an okina. So, the name should sound like H O u mu a mu a. Before the introduction of the new scheme, the object was referred to as A/2017 U1.

    More information

    This research was presented in a paper entitled A brief visit from a red and extremely elongated interstellar asteroid, by K. Meech et al., to appear in the journal Nature on 20 November 2017.

    The team is composed of Karen J. Meech (Institute for Astronomy, Honolulu, Hawai`i, USA [IfA]) Robert Weryk (IfA), Marco Micheli (ESA SSA-NEO Coordination Centre, Frascati, Italy; INAF–Osservatorio Astronomico di Roma, Monte Porzio Catone, Italy), Jan T. Kleyna (IfA) Olivier Hainaut (ESO, Garching, Germany), Robert Jedicke (IfA) Richard J. Wainscoat (IfA) Kenneth C. Chambers (IfA) Jacqueline V. Keane (IfA), Andreea Petric (IfA), Larry Denneau (IfA), Eugene Magnier (IfA), Mark E. Huber (IfA), Heather Flewelling (IfA), Chris Waters (IfA), Eva Schunova-Lilly (IfA) and Serge Chastel (IfA).

    See the full article here .

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    ESO is the foremost intergovernmental astronomy organisation in Europe and the world’s most productive ground-based astronomical observatory by far. It is supported by 16 countries: Austria, Belgium, Brazil, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Poland, Portugal, Spain, Sweden, Switzerland and the United Kingdom, along with the host state of Chile. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world’s most advanced visible-light astronomical observatory and two survey telescopes. VISTA works in the infrared and is the world’s largest survey telescope and the VLT Survey Telescope is the largest telescope designed to exclusively survey the skies in visible light. ESO is a major partner in ALMA, the largest astronomical project in existence. And on Cerro Armazones, close to Paranal, ESO is building the 39-metre European Extremely Large Telescope, the E-ELT, which will become “the world’s biggest eye on the sky”.

    ESO LaSilla
    ESO/Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres.

    VLT at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level.

    ESO Vista Telescope
    ESO/Vista Telescope at Cerro Paranal, with an elevation of 2,635 metres (8,645 ft) above sea level.

    ESO/NTT at Cerro LaSilla 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO VLT Survey telescope
    VLT Survey Telescope at Cerro Paranal with an elevation of 2,635 metres (8,645 ft) above sea level.

    ALMA Array
    ALMA on the Chajnantor plateau at 5,000 metres.

    ESO/E-ELT to be built at Cerro Armazones at 3,060 m.

    APEX Atacama Pathfinder 5,100 meters above sea level, at the Llano de Chajnantor Observatory in the Atacama desert.

    Leiden MASCARA instrument, La Silla, located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)

    Leiden MASCARA cabinet at ESO Cerro la Silla located in the southern Atacama Desert 600 kilometres (370 mi) north of Santiago de Chile at an altitude of 2,400 metres (7,900 ft)

    ESO Next Generation Transit Survey at Cerro Paranel, 2,635 metres (8,645 ft) above sea level

    SPECULOOS four 1m-diameter robotic telescopes 2016 in the ESO Paranal Observatory, 2,635 metres (8,645 ft) above sea level

    ESO TAROT telescope at Paranal, 2,635 metres (8,645 ft) above sea level

  • richardmitnick 10:29 am on November 20, 2017 Permalink | Reply
    Tags: "A Model of Leptons", , , , , , ,   

    From CERN: “50 years since iconic ‘A Model of Leptons’ published” 

    Cern New Bloc

    Cern New Particle Event

    CERN New Masthead


    20 Nov 2017
    Harriet Kim Jarlett

    This event shows the real tracks produced in the 1200 litre Gargamelle bubble chamber that provided the first confirmation of a neutral current interaction. (Image: CERN)


    Steven Weinberg

    Today, 50 years ago, Steven Weinberg published the iconic paper A Model of Leptons [Physical Review Letters], which explains the profound link between mathematics and nature.


    This paper lies at the core of the Standard Model, our most complete theory of how particles interact in our universe.

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.

    Just two pages long, Weinberg’s elegant and simply written theory was revolutionary at the time, yet was virtually ignored for many years. But now, it is cited at least three times a week.

    The paper uses the idea of symmetry – that everything in our universe has a corresponding mirror image – between particles called pions to build Weinberg’s theory of the fundamental forces.

    From 1965 Weinberg had been building a mathematical structure and theorems based on this symmetry that explained why physicists had observed certain interactions between pions and nucleons and how pions behave when they are scattered from one another. This paved the way for a whole theory of hadronic physics at low energy.

    “It’s what keeps you going as a theoretical physicist to hope that one of your squiggles will turn out to describe reality.”
    Steven Weinberg, Nobel prize winner and author of A Model of Leptons

    Physicists had been using the concept of symmetry since the 1930’s, but had not yet been able to unite the electromagnetic and weak forces. Uniting the two forces would bring physicists closer to a single theory describing how and why all the fundamental interactions in our universe occur. The mathematics needed the particles carrying these two forces to be massless, but Weinberg and other physicists knew that if the particles really created these forces in nature, they had to be very heavy.

    One day, as the 34-year-old Weinberg was driving his red Camero to work, he had a flash of insight – he had been looking for massless particles in the wrong place. He applied his theory to a rarely mentioned and often disregarded particle, the massive W boson, and paired it with a massless photon. Theorists accounted for the mass of the W by introducing another unseen mechanism. This later became known as the Higgs mechanism, which calls for the existence of a Higgs boson.

    Proving the validity of Weinberg’s theory inspired one of the biggest experimental science programmes ever seen and CERN has built major projects with these discoveries at their heart: the Gargamelle bubble chamber found the first evidence of the electroweak current in 1973; the Super Proton Synchrotron showed, in 1982, the first evidence of the W boson; and most recently the Large Hadron Collider, in 2012, confirmed the existence of the Higgs Boson.

    CERN Super Proton Synchrotron


    CERN/LHC Map

    CERN LHC Tunnel

    CERN LHC particles

    CERN CMS Higgs Event

    CERN/CMS Detector

    CERN ATLAS Higgs Event

    CERN/ATLAS detector

    Steven Weinberg visiting the ATLAS collaboration in 2009. (Image: Maximilien Brice/CERN)

    Speaking to the CERN Courier Weinberg, now 84, describes what it’s like to see his work confirmed: “It’s what keeps you going as a theoretical physicist to hope that one of your squiggles will turn out to describe reality.” He received the Nobel Prize for this iconic, game-changing theory in 1979.

    Half a century after this publication, it’s hard to find a theory that explains fundamental physics as clearly as Weinberg’s, which brought together all the different pieces of the puzzle and assembled them into one, very simple idea.

    Read more about the original theory, and an interview with Steven Weinberg in this month’s CERN Courier.

    See the full article here.

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  • richardmitnick 9:15 am on November 20, 2017 Permalink | Reply
    Tags: , , , , , Exoplanet HD76920b   

    From COSMOS: “We’ve found an exo-planet with an extraordinarily eccentric orbit” 

    Cosmos Magazine bloc

    COSMOS Magazine

    18 November 2017
    Jonti Horner
    Vice Chancellor’s Senior Research Fellow, University of Southern Queensland

    Jake Clark
    PhD Student, University of Southern Queensland

    Rob Wittenmyer
    Associate Professor (Astrophysics), University of Southern Queensland

    Stephen Kane
    Associate Professor, University of California, Riverside

    A newly discovered world could expand our understanding of planet formation.

    An artist’s impression of the exoplanet in close orbit to a star.
    ESA, NASA, G. Tinetti (University College London, UK & ESA) and M. Kornmesser (NASA/ESA Hubble)

    The discovery of a planet with a highly elliptical orbit around an ancient star could help us understand more about how planetary systems form and evolve over time.

    The new planet, HD76920b, is four times the mass of Jupiter, and can be found some 587 light years away in the southern constellation Volans, the Flying Fish. At its furthest, it orbits almost twice as far from its star as Earth does from the Sun.

    Superimposing HD76920b’s orbit on the Solar system shows how peculiar it is. Its orbit is more like that of the asteroid Phaethon than any of the Solar system’s planets. Jake Clark

    Details of the planet and its discovery are published today [Accepted for publication in AJ]. So how does this fit into the planet formation narrative, and are planets like it common in the cosmos?

    The Solar system

    Before the first exoplanet discovery, our understanding of how planetary systems formed came from the only example we had at the time: our Solar system.

    Close to the Sun orbit four rocky planets – Mercury, Venus, Earth and Mars. Further out are four giants – Jupiter, Saturn, Uranus and Neptune.

    Scattered in their midst we have debris – comets, asteroids and the dwarf planets.

    The eight planets move in almost circular orbits, close to the same plane. The bulk of the debris also lies close to that plane, although on orbits that are somewhat more eccentric and inclined.

    How did this system form? The idea was that it coalesced from a disk of material surrounding the embyronic Sun. The colder outer reaches were rich in ices, while the hotter inner regions contained just dust and gas.

    The Solar system formed from a protoplanetary disk, surrounding the young Sun. NASA/JPL-Caltech

    Over millions of years, the tiny particles of dust and ice collided with one another, slowly building ever larger objects. In the icy depths of space, the giant planets grew rapidly. In the hot, rocky interior, growth was slower.

    Eventually, the Sun blew away the gas and dust leaving a (relatively) orderly system – roughly co-planar planets, moving on near-circular orbits.

    The exoplanet era

    The first exoplanets, discovered in the 1990s, shattered this simple model of planet formation. We quickly learned that they are far more diverse than we could have possibly imagined.

    Some systems feature giant planets, larger than Jupiter, orbiting incredibly close to their star. Others host eccentric, solitary worlds, with no companions to call their own.

    Artist’s impression of the Hot Jupiter HD209458b – a planet so close to its star that its atmosphere is evaporating to space.
    European Space Agency, A.Vidal-Madjar (Institut d’Astrophysique de Paris, CNRS, France) and NASA

    This wealth of data reveals one thing – planet formation and evolution is more complicated and diverse than we ever imagined.

    Core accretion vs dynamical instability

    Massive protoplanetary disks can become unstable, rapidly giving birth to giant planets. No video credit.

    Both models can explain some, but not all, of the newly discovered planets. Depending on the initial conditions around the star, it seems that both processes can occur.

    Each theory offers potential to explain eccentric worlds in somewhat different ways.

    How do you get an eccentric planet?

    In the dynamical instability model you can easily get several clumps forming and interacting, slinging one another around until their orbits are both tilted and eccentric.

    Under the core accretion model things are a bit harder, as this method naturally creates co-planar, ordered planetary systems. But over time those systems can become unstable.

    One possible outcome is for one planet to eject the others through a series of chaotic encounters. That would naturally leave it as a solitary body, following a highly elongated orbit.

    Chaotic planetary systems can eject planets entirely, leading to lonely rogue planets. NASA/JPL-Caltech.

    But there is another option. Many stars in our galaxy are binary – they have stellar companions. The interactions between a planet and its host star’s sibling could readily stir it up and eventually eject it, or place it on an extreme orbit.

    An eccentric planet

    This brings us to our newly discovered world, HD76920b. A handful of similarly eccentric worlds have been found before, but HD76920b is unique. It orbits an ancient star, more than two billion years older than the Sun.

    The orbit HD76920b is following is not tenable in the long-term. As it swings close to its host star, it will experience dramatic tides.

    A gaseous planet, HD76920b will change shape as it swings past its star, stretched by its enormous gravity. Those tides will be far greater than any we experience on Earth.

    That tidal interaction will act over time to circularise the planet’s orbit. The point of closest approach to the star will remain unchanged, but the most distant point will gradually be dragged closer in, driving the orbit towards circularity.

    All of this suggests that HD76920b cannot have occupied its current orbit since its birth. If that were the case, the orbit would have circularised aeons ago.

    Extremely eccentric planets have been discovered before, but this is the first around such an ancient star. Goddard Space Flight Center/NASA.

    Perhaps what we’re seeing is evidence of a planetary system gone rogue. A system that once contained several planets on circular (or near circular) orbits.

    Over time, those planets nudged one another around, eventually hitting a chaotic architecture as their star evolved. The result – chaos – with most planets scattered and flung to the depths of space leaving just one – HD76920b.

    The truth is, we just don’t know – yet. As is always the case in astronomy, more observations are needed to truly understand the life story of this peculiar planet.

    One thing we do know is the story is coming to a fiery end. In the next few million years, the star will swell, devouring its final planet. Then, HD76920b will be no more.

    See the full article here .

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  • richardmitnick 8:50 am on November 20, 2017 Permalink | Reply
    Tags: , , , , , , Dying star blows aluminium, , , silicon into space, The silicon is there but remains as silicon oxide gas rather than condensing into dust particles, W-Hydrae   

    From COSMOS: “Dying star blows aluminium, silicon into space” 

    Cosmos Magazine bloc

    COSMOS Magazine

    20 November 2017
    Richard A Lovett

    Research adds clues to how old stars supply the building blocks for new planets.

    ESO/NRAO/NAOJ ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres

    ALMA’s telescopes are watching as a dying star flings aluminium into space. ESO/NRAO/NAOJ

    Astronomers using a giant telescope array on high in the Chilean desert are mapping how solar winds blowing off a dying star distribute important planet-forming materials into space, adding a new layer to our understanding of how the death of old stars helps fuel the birth of planets such as ours.

    The star in question, called W-Hydrae, is a large red one 254 light years away in the constellation Hydrae. It is slightly too dim to be seen with the naked eye.

    Nearing the end of its life, W-Hydrae is in a phase of stellar evolution during which stars are known to eject significant quantities of elements heavier than hydrogen and helium into space. This process enriches the gas and dust clouds from which new stars and planetary systems will later form.

    “Some of the ejected materials form the next generation of stars and planets,” says Aki Takigawa, an astromineralogist at Kyoto University, Japan.

    Using a collection of 66 radio telescopes known as the Atacama Large Millimetre/submillimetre Array (ALMA), Takigawa’s team was able to zoom in on this star so closely that they could see features as small as 0.035 arc-seconds, or one-one-thousandth of a degree. At that distance, Takigawa says, it is possible to see features smaller than the star itself, although the star is so huge that it would fill our entire solar system well out into the Asteroid Belt.

    These molecules included aluminium monoxide (AlO), which condenses into aluminium-containing grains as it cools, and silicon oxide (SiO), which condenses into rock-like silicate dust. They escape the star not just because they are blasted off its surface at high speeds, but because radiation pressure from the star’s light creates a stellar wind that steadily accelerates them and sweeps them off toward interstellar space.

    One of the mysteries of this process, however, has been that while silicon is much more common in the galaxy as a whole than aluminium, the regions around stars such as W-Hydrae appear to be unexpectedly rich in aluminium oxide particles.

    The new research, published earlier this month in Science Advances, found that this might be due to a combination of factors. One is that aluminium oxide particles condense from vapour at a higher temperature than silicate particles. That means that they form closer to the star than the silicates.

    Once formed and accumulated to sufficient quantities, the particles are subject to radiation pressure, which accelerates them outward, carrying other gases with them. The result is that the later-to-condense silicon oxide molecules are picked up in the maelstrom and blown away from the star so fast that by the time they have cooled enough to condense they are too dispersed to do so.

    In other words, the silicon is there, but remains as silicon oxide gas, rather than condensing into dust particles.

    “Our estimation showed that more than 70% of SiO molecules remain in the gas phase,” Takigawa says.

    All of this is important, she adds, because planetary scientists studying our own solar system have found “pre-solar” aluminium oxide and silicate grains in primitive meteorites — grains that were formed before the solar system and have remained unaltered over the ensuing billions of years.

    The stars that formed these grains died more than 4.6 billion years ago, she says, “but we can now study similar stars with telescopes”.

    Brad Tucker, an astrophysicist and cosmologist at Australian National University, agrees. Finding large amounts of aluminum oxide dust, he adds, is quite interesting because some of the first exoplanet atmospheres that have been measured contain another metal oxide, titanium oxide.

    “I bring this up because the dust and gas that leaves [stars like W-Hydrae] will eventually form new star systems and planets,” he says, “and some of the new planets we are finding are weird.

    “A big question has always been to try to understand where all the gas and dust in the universe comes from, because eventually that will help tell us how new things are formed.”

    An important next step, he notes, will be to use ALMA to take images of exploding stars. “The dust involved in supernova explosions has lots of questions that need to be solved,” he says.

    See the full article here .

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  • richardmitnick 8:25 am on November 20, 2017 Permalink | Reply
    Tags: , Inbound Controlled Air-Releasable Unrecoverable Systems (ICARUS) program, , the MORSE Corp, Using Daylight to Make Drones Disappear   

    From MIT: “Using Daylight to Make Drones Disappear” 

    MIT News

    MIT Widget


    November 6, 2017
    Jay London

    An MIT alum-founded startup has developed a polymer that disappears when exposed to sunlight. Credit: DARPA

    In 2016, the MORSE Corp. began a project with the US Department of Defense (DoD) centered on a request that seems more science fiction than reality. The MIT alumni-founded company was asked to develop a small, single-use autonomous aircraft that can fly nearly 100 miles and land within roughly 30 feet of its target. And then it had to completely disappear within four hours after landing or 30 minutes after sunrise.

    “Developing an aircraft that can meet the accuracy and range requirement alone is a challenge,” says MORSE CEO Andreas Kellas SM ’07. “But add in the disappearing requirement and the problem becomes nearly impossible. That’s when you have to apply the MIT mentality: be creative, tenacious, and figure out how to make the impossible happen.”

    The result, which is in the advanced research stage, is the Inbound, Controlled, Air-Releasable, Unrecoverable Systems (ICARUS) program, a collaboration between MORSE and the DoD’s Defense Advanced Research Projects Agency (DARPA). The agency hopes the drones could be used to deliver critical supplies to isolated individuals in combat or civilians in need during epidemics or natural disasters.

    “This is critical capability that could save countless lives,” Kellas says. “Our warfighters and those of our allies often operate in forward areas where their discovery would compromise their safety. This system would enable the resupply of lifesaving antivenin, blood transfusion kit, and other critical items without compromising their position.”

    To make the disappearing drones a reality, MORSE developed a self-flying vehicle that is made from lightweight film that contains a guidance system smaller than a tennis ball. The vehicle is made of specially developed polymers that, when exposed to heat or sunlight, quickly depolymerize, or disintegrate, into a clear liquid substance, leaving only the guidance system and delivered supplies upon landing.

    The vehicle is made of specially developed polymers that, when exposed to heat or sunlight, quickly disintegrate. Credit: DARPA

    The MORSE team demonstrated a successful official high altitude flight test earlier this summer, followed by a successful depolymerization demo of its disappearing material.

    The ICARUS program, while unique in its goal, is similar to other technology-transfer projects executed by MORSE (which stands for Mission-Oriented Rapid-Solution Engineering). In 2016, the Cambridge-based MORSE worked with the DoD to create an Avalanche Prediction App, which the department hopes will help soldiers avoid disaster in remote, avalanche-prone mountainous regions like Afghanistan.

    “We combined nearly 100 years of alpine mountaineering knowledge, real-time weather forecasts, digital terrain data, in-situ measurements, and historical avalanche data,” Kellas says. “It’s an intelligent assimilation system that helps users visually map out and quantify risk.”

    Kellas and fellow AeroAstro alumnus Bobby Cohanim SM ’04, ScD ’13 started MORSE in 2014 after working together for nearly a decade at Draper Laboratory, when they saw a need for a company that could work with clients and quickly turn basic research into a field-ready operational system. MORSE’s 25 employees—who each own a percentage of the company—are nearly half MIT alumni.

    “For one person at MORSE to be successful, we all have to be successful,” says Cohanim. “We’re a group of individuals with disparate disciplines and broad skillsets. Our goal is to solve hard problems quickly and put the solutions in the field as soon as possible.”

    See the full article here .

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    The mission of MIT is to advance knowledge and educate students in science, technology, and other areas of scholarship that will best serve the nation and the world in the twenty-first century. We seek to develop in each member of the MIT community the ability and passion to work wisely, creatively, and effectively for the betterment of humankind.

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  • richardmitnick 8:10 am on November 20, 2017 Permalink | Reply
    Tags: , , , , , , NGC 7822   

    From Manu Garcia: “NGC 7822” 

    Manu Garcia, a friend from IAC.

    The universe around us.
    Astronomy, everything you wanted to know about our local universe and never dared to ask.


    The young stars are cleaning their nursery in NGC 7822. Within The Nebula, the bright edges and complex dust sculptures dominate this detailed deep image taken in infrared light by NASA’s wide field asteroid survey explorer.

    NASA/WISE Telescope

    NGC 7822 is located on the edge of a giant molecular cloud to the Northern Constellation Cepheus, a bright star formation region that is about 3.000 Light-years away. The atomic emission of light by the gas of the nebula is driven by the energy radiation of the hot stars, whose powerful winds and light also sculpt and erode the denser forms of the pillars. The Stars could still be forming within the pillars by the gravitational collapse, but as the pillars erode, any star that is formed will eventually isolate itself from its stellar matter reserve. This field covers about 40 Light-years at the estimated distance of NGC 7822.

    See the full article here .

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  • richardmitnick 6:55 pm on November 18, 2017 Permalink | Reply
    Tags: , , , , , , ,   

    From Futurism: “Measurements From CERN Suggest the Possibility of a New Physics” 



    November 18, 2017
    Brad Bergan

    A New Quantum Physics?


    During the mid- to late-twentieth century, quantum physicists picked apart the unified theory of physics that Einstein’s theory of relativity offered. The physics of the large was governed by gravity, but only quantum physics could describe observations of the small. Since then, a theoretical tug-o-war between gravity and the other three fundamental forces has continued as physicists try to extend gravity or quantum physics to subsume the other as more fundamental.

    Recent measurements from the Large Hadron Collider show a discrepancy with Standard Model predictions that may hint at entirely new realms of the universe underlying what’s described by quantum physics.


    CERN/LHC Map

    CERN LHC Tunnel

    CERN LHC particles

    The Standard Model of elementary particles (more schematic depiction), with the three generations of matter, gauge bosons in the fourth column, and the Higgs boson in the fifth.

    Although repeated tests are required to confirm these anomalies, a confirmation would signify a turning point in our most fundamental description of particle physics to date.

    Image credit: starsandspirals

    Quantum physicists found in a recent study [JHEP} that mesons don’t decay into kaon and muon particles often enough, according to the Standard Model predictions of frequency. The authors agree that enhancing the power [The Guardian] of the Large Hadron Collider (LHC) will reveal a new kind of particle responsible for this discrepancy. Although errors in data or theory may have caused the discrepancy, instead of a new particle, an improved LHC would prove a boon for several projects on the cutting edge of physics.

    The Standard Model

    The Standard Model is a well-established fundamental theory of quantum physics that describes three of the four fundamental forces believed to govern our physical reality. Quantum particles occur in two basic types, quarks and leptons. Quarks bind together in different combinations to build particles like protons and neutrons. We’re familiar with protons, neutrons, and electrons because they’re the building blocks of atoms.

    The “lepton family” features heavier versions of the electron — like the muon — and the quarks can coalesce into hundreds of other composite particles. Two of these, the Bottom and Kaon mesons, were culprits in this quantum mystery. The Bottom meson (B) decays to a Kaon meson (K) accompanied by a muon (mu-) and anti-muon (mu+) particle.

    The Anomaly

    They found a 2.5 sigma variance, or 1 in 80 probability, “which means that, in the absence of unexpected effects, i.e. new physics, a distribution more deviant than observed would be produced about 1.25 percent of the time,” Professor Spencer Klein, senior scientist at Lawrence Berkeley National Laboratory, told Futurism. Klein was not involved in the study.

    This means the frequency of mesons decaying into strange quarks during the LHC proton-collision tests fell a little below the expected frequency. “The tension here is that, with a 2.5 sigma [or standard deviation from the normal decay rate], either the data is off by a little bit, the theory is off by a little bit, or it’s a hint of something beyond the standard model,” Klein said. “I would say, naïvely, one of the first two is correct.”

    To Klein, this variance is inevitable considering the high volume of data run by computers for LHC operations. “With Petabyte-(1015 bytes)-sized datasets from the LHC, and with modern computers, we can make a very large number of measurements of different quantities,” Klein said. “The LHC has produced many hundreds of results. Statistically, some of them are expected to show 2.5 sigma fluctuations.” Klein noted that particle physicists usually wait for a 5-sigma fluctuation before crying wolf — corresponding to roughly a 1-in-3.5-million fluctuation in data [].

    These latest anomalous observations do not exist in a vacuum. “The interesting aspect of the two taken in combination is how aligned they are with other anomalous measurements of processes involving B mesons that had been made in previous years,” Dr. Tevong You, co-author of the study and junior research fellow in theoretical physics at Gonville and Caius College, University of Cambridge, told Futurism. “These independent measurements were less clean but more significant. Altogether, the chance of measuring these different things and having them all deviate from the Standard Model in a consistent way is closer to 1 in 16000 probability, or 4 sigma,” Tevong said.

    Extending the Standard Model

    Barring statistical or theoretical errors, Tevong suspects that the anomalies mask the presence of entirely new particles, called leptoquarks or Z prime particles. Inside bottom mesons, quantum excitations of new particles could be interfering with normal decay frequency. In the study, researchers conclude that an upgraded LHC could confirm the existence of new particles, making a major update to the Standard Model in the process.

    “It would be revolutionary for our fundamental understanding of the universe,” said Tevong. “For particle physics […] it would mean that we are peeling back another layer of Nature and continuing on a journey of discovering the most elementary building blocks. This would have implications for cosmology, since it relies on our fundamental theories for understanding the early universe,” he added. “The interplay between cosmology and particle physics has been very fruitful in the past. As for dark matter, if it emerges from the same new physics sector in which the Zprime or leptoquark is embedded, then we may also find signs of it when we explore this new sector.”

    The Power to Know

    So far, scientists at the LHC have only observed ghosts and anomalies hinting at particles that exist at higher energy levels. To prove their existence, physicists “need to confirm the indirect signs […], and that means being patient while the LHCb experiment gathers more data on B decays to make a more precise measurement,” Tevong said.


    “We will also get an independent confirmation by another experiment, Belle II, that should be coming online in the next few years. After all that, if the measurement of B decays still disagrees with the predictions of the Standard Model, then we can be confident that something beyond the Standard Model must be responsible, and that would point towards leptoquarks or Zprime particles as the explanation,” he added.

    To establish their existence, physicists would then aim to produce the particles in colliders the same way Bottom mesons or Higgs bosons are produced, and watch them decay. “We need to be able to see a leptoquark or Zprime pop out of LHC collisions,” Tevong said. “The fact that we haven’t seen any such exotic particles at the LHC (so far) means that they may be too heavy, and more energy will be required to produce them. That is what we estimated in our paper: the feasibility of directly discovering leptoquarks or Zprime particles at future colliders with higher energy.”

    Quantum Leap for the LHC

    Seeking out new particles in the LHC isn’t a waiting game. The likelihood of observing new phenomena is directly proportional to how many new particles pop up in collisions. “The more the particle appears the higher the chances of spotting it amongst many other background events taking place during those collisions,” Tevong explained. For the purposes of finding new particles, he likens it to searching for a needle in a haystack; it’s easier to find a needle if the haystack is filled with them, as opposed to one. “The rate of production depends on the particle’s mass and couplings: heavier particles require more energy to produce,” he said.

    This is why Tevong and co-authors B.C. Allanach and Ben Gripaios recommend either extending the LHC loop’s length, thus reducing the amount of magnetic power needed to accelerate particles, or replacing the current magnets with stronger ones.

    According to Tevong, the CERN laboratory is slated to keep running the LHC in present configuration until mid-2030s. Afterwards, they might upgrade the LHC’s magnets, roughly doubling its strength. In addition to souped-up magnets, the tunnel could see an enlargement from present 27 to 100 km (17 to 62 miles). “The combined effect […] would give about seven times more energy than the LHC,” Tevong said. “The timescale for completion would be at least in the 2040s, though it is still too early to make any meaningful projections.”

    If the leptoquark or Z prime anomalies are confirmed, the Standard Model has to change, Tevong reiterates. “It is very likely that it has to change at energy scales directly accessible to the next generation of colliders, which would guarantee us answers,” he added. While noting that there’s no telling if dark matter has anything to do with the physics behind Zprimes or leptoquarks, the best we can do is seek “as many anomalous measurements as possible, whether at colliders, smaller particle physics experiments, dark matter searches, or cosmological and astrophysical observations,” he said. “Then the dream is that we may be able to form connections between various anomalies that can be linked by a single, elegant theory.”

    See the full article here .

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    Futurism covers the breakthrough technologies and scientific discoveries that will shape humanity’s future. Our mission is to empower our readers and drive the development of these transformative technologies towards maximizing human potential.

  • richardmitnick 2:52 pm on November 18, 2017 Permalink | Reply
    Tags: , , , , , Could Matter Escape The Event Horizon During A Black Hole Merger?,   

    From Ethan Siegel: ” Could Matter Escape The Event Horizon During A Black Hole Merger?” 

    Ethan Siegel

    Nov 18, 2017

    Nothing can escape from a black hole… but could another black hole pull something out?

    Even though black holes should have accretion disks, and matter falling in from them, it doesn’t appear to be possible to escape from inside the event horizon once you cross over. Could anything change that? Image credit: NASA / Dana Berry (Skyworks Digital).

    Once you fall into the event horizon of a black hole, you can never escape. There’s no speed you could travel at, not even the speed of light, that would enable you to get out. But in General Relativity, space gets curved by the presence of mass and energy, and merging black holes are one of the most extreme scenarios of all. Is there any way that you could fall into a black hole, cross the event horizon, and then escape as your black hole’s event horizon gets distorted from a massive merger? That’s the question of Chris Mitchell, who asks:

    If two black holes merge, is it possible for matter that was within the event horizon of one black hole to escape? Could it escape and migrate to the other (more massive black hole)? What about escape to outside of both horizons?

    It’s a crazy idea, to be certain. But is it crazy enough to work? Let’s find out.

    When a massive enough star ends its life, or two massive enough stellar remnants merge, a black hole can form, with an event horizon proportional to its mass and an accretion disk of infalling matter surrounding it. Image credit: NASA/ESA Hubble, ESO, M. Kornmesser.

    The way you form a black hole is typically from the collapse of a massive star’s core, either in the aftermath of a supernova explosion, a neutron star merger, or via direct collapse. As far as we know, every black hole is formed out of matter that was once a part of a star, and so in many ways black holes are the ultimate stellar remnant. Some black holes form in isolation; others form as part of a binary system or even one with multiple stars. Over time, black holes can not only inspiral and merge, but devour other matter that falls inside the event horizon.

    In a Schwarzschild black hole, falling in leads you to the singularity, and darkness. No matter which direction you travel in, how you accelerate, etc., a crossover into the event horizon means an inevitable encounter with a singularity. Image credit: (Illustration) ESO, NASA/ESA Hubble, M. Kornmesser.

    When anything crosses into a black hole’s event horizon from the outside, that matter is immediately doomed. Inevitably, in a matter of mere seconds, it will find itself encountering the singularity at the center of a black hole: a single point for a non-rotating black hole, and a ring for a rotating one. The black hole itself will have no memory of which particles fell in or what their quantum state was. Instead, all that will remain, information-wise, is what the total mass, charge, and angular momentum of the black hole now is.

    In the final pre-merger stages, the spacetime surrounding a black hole pair will be distorted, as matter continues to fall into both black holes from the surrounding environment. At no point does it appear that anything will have the opportunity to escape from the inside to the outside of an event horizon. Image credit: NASA/Ames Research Center/C. Henze.

    So you might envision a scenario, then, where matter falls into a black hole during the final pre-merger stages, when one black hole is about to combine with another. Since black holes are always expected to have accretion disks, and throughout interstellar space there’s material simply zipping through, you should have particles crossing the event horizon all the time. That part’s a no-brainer, and so it makes sense to consider a particle that’s just entered the event horizon prior to the final moments of a merger.

    Could it possibly escape? Could it “jump” from one black hole to the other? Let’s examine the situation from a spacetime perspective.

    Computer simulation of two merging black holes and the spacetime distortions that they cause. While gravitational waves are copiously emitted, matter itself isn’t expected to escape. Image credit: MPI for Gravitational Physics Werner Benger, cc by-sa 4.0.

    When two black holes merge, they do so only after a long period of inspiral, where energy is radiated away via gravitational waves. Leading up to the final pre-merger moments, energy is radiated away. But that doesn’t cause the event horizon of either black hole to shrink; rather, that energy comes from spacetime in the center-of-mass region getting more and more heavily deformed. It’s the same as if you stole energy away from the planet Mercury; it would orbit closer to the Sun, but no properties of Mercury or the Sun would need to change.

    However, when the final moments of the merger are upon us, the event horizons of the two black holes do get deformed by the gravitational presence of one another. Fortunately, numerical relativists [Physical Review D] have already worked out exactly how this merger affects the event horizons, and it’s spectacularly informative.

    Despite the fact that up to ~5% of the total pre-merger mass of the black holes can be radiated away in the form of gravitational waves, you’ll notice that the event horizons never shrink; they simply grow a connection, distort a little bit, and then increase in total volume. That last point is important: if I have two black holes of equal mass, their event horizons take up a certain amount of volume in space. If I merge them to create a single black hole of double the mass of the two originals, the amount of volume taken up by the event horizon is now four times the original volume of the combined black holes. The mass of a black hole is directly proportional to its radius, but volume is proportional to radius cubed.

    While we’ve discovered a great many black holes, note that the radius of each one’s event horizon is directly proportional to its mass. Double the mass, double the radius, but that means the area increases fourfold and the volume increases eightfold! Image credit: LIGO/Caltech/Sonoma State (Aurore Simonnet).

    As it turns out, even if you kept a particle as close to stationary inside a black hole as possible, and made it fall towards the singularity as slowly as possible, there’s no way for it to get out. The total volume of the combined event horizons during a black hole merger goes up, not down, and no matter what the trajectory of an event-horizon-crossing particle is, it’s forever destined to be swallowed by the combined singularity of both black holes together.

    In many collision scenarios in astrophysics, there are ejecta, where matter from inside an object escapes during a cataclysmic event. But in the case of merging black holes, everything from inside remains inside; most of what was outside gets sucked in; and only a little bit of what was outside could conceivably escape. Once you fall in, you’re doomed, and nothing you throw at that black hole — even another black hole — will change that!

    See the full article here .

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    “Starts With A Bang! is a blog/video blog about cosmology, physics, astronomy, and anything else I find interesting enough to write about. I am a firm believer that the highest good in life is learning, and the greatest evil is willful ignorance. The goal of everything on this site is to help inform you about our world, how we came to be here, and to understand how it all works. As I write these pages for you, I hope to not only explain to you what we know, think, and believe, but how we know it, and why we draw the conclusions we do. It is my hope that you find this interesting, informative, and accessible,” says Ethan

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