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  • richardmitnick 8:17 am on September 15, 2022 Permalink | Reply
    Tags: "Put a Ring On It:: How Gravity Gives Astronomers a Powerful Lens On the Universe", , , , Radio Astronomy,   

    From The National Radio Astronomy Observatory: “Put a Ring On It:: How Gravity Gives Astronomers a Powerful Lens On the Universe” 

    NRAO Banner

    From The National Radio Astronomy Observatory

    9.14.22

    1
    The first deep field image from the James Webb Space Telescope. Notice the arcs of light caused by gravitational lensing. Credit: NASA, ESA, CSA, STScI.

    2
    The first image of an Einstein Ring. It was captured by the VLA [below] in 1987. Credit: NRAO/AUI/NSF.

    3
    ALMA’s [below] highest resolution image ever reveals the dust glowing inside the distant galaxy SDP.81. The ring structure was created by a gravitational lens that distorted the view of the distant galaxy into a ring-like structure. Credit: ALMA (NRAO/ESO/NAOJ)[below].

    In 1919 astronomers Arthur Eddington and Andrew Crommelin captured photographic images of a total solar eclipse.

    The Sun was in the constellation Taurus at the time, and a handful of its stars could be seen in the photographs. But the stars weren’t quite in their expected place. The tremendous gravity of the Sun had deflected the light of these stars, making them appear slightly out of place. It was the first demonstration that gravity could change the path of light, just as predicted by Albert Einstein in 1915.

    The bending of light by the mass of a star or galaxy is one of the central predictions of General Relativity. Although Einstein first predicted the deflection of light from a single star, others such as Oliver Lodge argued that a large mass could act as a gravitational lens, warping the path of light similar to the way a glass lens focuses light.

    By 1935, Einstein demonstrated how light from a distant galaxy could be warped by a galaxy in front of it to create a ring of light. Such an Einstein Ring, as it came to be known, would make the distant galaxy appear as a ring or arc of light around the closer galaxy. But Einstein thought this effect would never be observed. These arcs of light would be too faint for optical telescopes to capture. Einstein was right until 1998 when the Hubble Space Telescope captured a ring around the galaxy B1938+666.

    This was the first optical ring to be observed, but it wasn’t the first Einstein Ring. The first ring was seen in radio light, and it was captured by the Very Large Array (VLA)[below].

    In 1987, a team of students at the MIT Research Lab in Electronics under Prof. Bernard Burke, and led by PhD student Jackie Hewitt, used the VLA to make detailed images of known radio-emitting objects. One of them, known as MG1131+0456, showed a distinct oval shape with two bright lobes. Hewitt and her team considered several models to explain the unusual shape, but only an Einstein Ring matched the data. Einstein’s galactic prediction was finally observed.

    Radio astronomy is particularly good at capturing lensed galaxies. They have become a powerful tool for radio astronomers. Just as a glass lens focuses light to make an object appear brighter and larger, so does a gravitational lens. By observing lensed galaxies radio astronomers can study galaxies that would be too distant and faint to see on their own. Einstein rings can be used to measure the mass of the closer galaxy or galactic cluster since the amount of gravitational lensing depends on the mass of the foreground galaxy.

    One of the more interesting aspects of gravitational lensing is that it can be used to measure the rate at which the universe expands. Light from a distant galaxy can take many different paths as it passes the foreground galaxy. Each of these paths can have different distances, which means the light can reach us at different times. We might see a burst of light from the galaxy multiple times, each from a different path. Astronomers can use this to calculate galactic distance, and thus the scale of the cosmos.

    Since the first detection of an Einstein ring by the VLA, radio astronomers have found more of them, and have captured them in more detail. In 2015, for example, the Atacama Large Millimeter/submillimeter Array (ALMA) made a detailed image of the lensed arcs from a distant galaxy named SDP.81. The image was sharp enough that astronomers could trace the arcs back to their source to study how stars formed within the galaxy.

    Einstein rings are now commonly seen in astronomical images, particularly in deep field images, such as those of the James Webb Space Telescope and others. As radio astronomy has shown, they are more than just beautiful. They give us a new lens on the cosmos.

    See the full article here .


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    The National Radio Astronomy Observatory is a facility of The National Science Foundation, operated under cooperative agreement by The Associated Universities, Inc.


    National Radio Astronomy Observatory Karl G Jansky Very Large Array located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes.

    ngVLA, to be located near the location of the NRAO Karl G. Jansky Very Large Array site on the plains of San Agustin, fifty miles west of Socorro, NM, at an elevation of 6970 ft (2124 m) with additional mid-baseline stations currently spread over greater New Mexico, Arizona, Texas, and Mexico.

    National Radio Astronomy Observatory Very Long Baseline Array.

    The European Southern Observatory [La Observatorio Europeo Austral][Observatoire européen austral][Europäische Südsternwarte](EU)(CL))/National Radio Astronomy Observatory/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

    Access to ALMA observing time by the North American astronomical community will be through the North American ALMA Science Center (NAASC).

    *The Very Long Baseline Array (VLBA) comprises ten radio telescopes spanning 5,351 miles. It’s the world’s largest, sharpest, dedicated telescope array. With an eye this sharp, you could be in Los Angeles and clearly read a street sign in New York City!

    Astronomers use the continent-sized VLBA to zoom in on objects that shine brightly in radio waves, long-wavelength light that’s well below infrared on the spectrum. They observe blazars, quasars, black holes, and stars in every stage of the stellar life cycle. They plot pulsars, exoplanets, and masers, and track asteroids and planets.

     
  • richardmitnick 10:45 pm on September 12, 2022 Permalink | Reply
    Tags: "Astronomers discover new brown dwarf with quasi-spherical mass loss", , , , , , Radio Astronomy, SSTc2d J163134.1-24006 is most likely a brown dwarf with a mass of about 0.05 solar masses and an elliptical shell of carbon monoxide., , The newfound object designated SSTc2d J163134.1-24006   

    From The National Radio Astronomy Observatory Via “phys.org” : “Astronomers discover new brown dwarf with quasi-spherical mass loss” 

    NRAO Banner

    From The National Radio Astronomy Observatory

    Via

    “phys.org”

    9.12.22

    1
    Herschel column-density map of the Ophiuchus molecular cloud. The magenta star indicates the location of SSTc2d J163134.1. The Lynds L1709 dark cloud in the region is indicated. Credit: Ruiz-Rodriguez et al., 2022.

    Astronomers report the detection of a new brown dwarf as part of the Ophiuchus Disk Survey Employing ALMA [below] (ODISEA) program. The newfound object designated SSTc2d J163134.1-24006, appears to be experiencing a quasi-spherical mass loss. The discovery was detailed in a paper published September 2 for The Astrophysical Journal [below].

    Brown dwarfs are intermediate objects between planets and stars, occupying the mass range between 13 and 80 Jupiter masses (0.012 and 0.076 solar masses). They can burn deuterium but are unable to burn regular hydrogen, which requires a minimum mass of at least 80 Jupiter masses and a core temperature of about 3 million K.

    A team of astronomers led by Dary Ruiz-Rodriguez of the National Radio Astronomy Observatory (NRAO) in Charlottesville, Virginia, have investigated SSTc2d J163134.1-24006, initially identified as a faint stellar object, under the ODISEA project, which is dedicated to study the entire population of protoplanetary disks in the Ophiuchus Molecular Cloud. They found that SSTc2d J163134.1-24006 is most likely a brown dwarf with a mass of about 0.05 solar masses and an elliptical shell of carbon monoxide (CO).

    “SSTc2d J163134.1 was observed as part of the ‘Ophiuchus Disk Survey Employing ALMA’ (ODISEA) program (Project ID: 2016.1.00545.S PI: L. Cieza). ALMA Band 6 (1.3 mm) observations were performed on April 27 and August 22, 2018, during Cycle 5 using the C43-3 configuration (15–500 m baselines),” the researchers wrote in the paper.

    First of all, the team serendipitously discovered an expanding shell of carbon monoxide ejected from an object, with a temperature below 3,000 K, located in the direction of the Ophiuchus Molecular Cloud. Further observations revealed that this shell is associated with SSTc2d J163134.1.

    In order to explain the nature of SSTc2d J163134.1 and its expanding shell, Ruiz-Rodriguez’s team considered various scenarios, including the inside-out collapse of a dense molecular core in the Ophiuchus cloud, the mass loss of a giant star in the distant background, or a shell of gas expelled from a young brown dwarf. According to the researchers, the most plausible one is the brown dwarf hypothesis.

    “We conclude that the source is not a giant star in the distant background (>5–10 kpc) and is most likely to be a young brown dwarf in the Ophiuchus cloud, at a distance of just ∼139 pc,” the astronomers explained.

    Given that emission of carbon monoxide from SSTc2d J163134.1 has an elliptical shape, it was noted that this makes it the first brown dwarf known to exhibit a quasi-spherical mass loss. The authors of the paper assume that a deuterium flash could be responsible for this phenomenon, but more detailed theoretical work is required in order to verify this explanation.

    Science paper:
    The Astrophysical Journal

    See the full article here .


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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The National Radio Astronomy Observatory is a facility of The National Science Foundation, operated under cooperative agreement by The Associated Universities, Inc.


    National Radio Astronomy Observatory Karl G Jansky Very Large Array located in central New Mexico on the Plains of San Agustin, between the towns of Magdalena and Datil, ~50 miles (80 km) west of Socorro. The VLA comprises twenty-eight 25-meter radio telescopes.

    ngVLA, to be located near the location of the NRAO Karl G. Jansky Very Large Array site on the plains of San Agustin, fifty miles west of Socorro, NM, at an elevation of 6970 ft (2124 m) with additional mid-baseline stations currently spread over greater New Mexico, Arizona, Texas, and Mexico.

    National Radio Astronomy Observatory Very Long Baseline Array.

    The European Southern Observatory [La Observatorio Europeo Austral][Observatoire européen austral][Europäische Südsternwarte](EU)(CL))/National Radio Astronomy Observatory/National Astronomical Observatory of Japan(JP) ALMA Array in Chile in the Atacama at Chajnantor plateau, at 5,000 metres.

    Access to ALMA observing time by the North American astronomical community will be through the North American ALMA Science Center (NAASC).

    *The Very Long Baseline Array (VLBA) comprises ten radio telescopes spanning 5,351 miles. It’s the world’s largest, sharpest, dedicated telescope array. With an eye this sharp, you could be in Los Angeles and clearly read a street sign in New York City!

    Astronomers use the continent-sized VLBA to zoom in on objects that shine brightly in radio waves, long-wavelength light that’s well below infrared on the spectrum. They observe blazars, quasars, black holes, and stars in every stage of the stellar life cycle. They plot pulsars, exoplanets, and masers, and track asteroids and planets.

     
  • richardmitnick 10:28 am on September 7, 2022 Permalink | Reply
    Tags: "'Lopsided' Universe could mean revision of standard cosmological model", , , , , , , Radio Astronomy,   

    From The University of Oxford (UK): “‘Lopsided’ Universe could mean revision of Standard Cosmological Model – ΛCDM Model of Cosmology” 

    U Oxford bloc

    From The University of Oxford (UK)

    9.7.22

    1

    Dr Sebastian von Hausegger and Professor Subir Sarkar from the Rudolf Peierls Centre for Theoretical Physics at Oxford, together with their collaborators Dr Nathan Secrest (US Naval Observatory, Washington), Dr Roya Mohayaee (Institut d’Astrophysique, Paris) and Dr Mohamed Rameez (Tata Institute of Fundamental Research, Mumbai), have made a surprising discovery about the Universe. Their paper is in press in The Astrophysical Journal Letters [below].

    The researchers used observations of over a million quasars and half a million radio sources to test the ‘cosmological principle’ which underlies modern cosmology. It says that when averaged on large scales the Universe is isotropic and homogeneous. This allows a simple mathematical description of space-time – the Friedmann-Lemaître-Robertson-Walker (FLRW) metric – which enormously simplifies the application of Albert Einstein’s General Theory of Relativity to the Universe as a whole, thus yielding the “standard cosmological model”. Interpretation of observational data in the framework of this model has however led to the astounding conclusion that about 70% of the Universe is in the form of a mysterious “dark energy” which is causing its expansion rate to accelerate.

    ___________________________________________________________________
    The Dark Energy Survey

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

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

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

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

    According to Albert Einstein’s Theory of General Relativity, gravity should lead to a slowing of the cosmic expansion. Yet, in 1998, two teams of astronomers studying distant supernovae made the remarkable discovery that the expansion of the universe is speeding up.
    Saul Perlmutter (center) [The Supernova Cosmology Project] shared the 2006 Shaw Prize in Astronomy, the 2011 Nobel Prize in Physics, and the 2015 Breakthrough Prize in Fundamental Physics with Brian P. Schmidt (right) and Adam Riess (left) [The High-z Supernova Search Team] for providing evidence that the expansion of the universe is accelerating.

    To explain cosmic acceleration, cosmologists are faced with two possibilities: either 70% of the universe exists in an exotic form, now called Dark Energy, that exhibits a gravitational force opposite to the attractive gravity of ordinary matter, or General Relativity must be replaced by a new theory of gravity on cosmic scales.

    The Dark Energy Survey is designed to probe the origin of the accelerating universe and help uncover the nature of Dark Energy by measuring the 14-billion-year history of cosmic expansion with high precision. More than 400 scientists from over 25 institutions in the United States, Spain, the United Kingdom, Brazil, Germany, Switzerland, and Australia are working on the project. The collaboration built and is using an extremely sensitive 570-Megapixel digital camera, DECam, mounted on the Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory, high in the Chilean Andes, to carry out the project.

    Over six years (2013-2019), the Dark Energy Survey collaboration used 758 nights of observation to carry out a deep, wide-area survey to record information from 300 million galaxies that are billions of light-years from Earth. The survey imaged 5000 square degrees of the southern sky in five optical filters to obtain detailed information about each galaxy. A fraction of the survey time is used to observe smaller patches of sky roughly once a week to discover and study thousands of supernovae and other astrophysical transients.
    ___________________________________________________________________
    This has been interpreted as arising from the zero-point fluctuations of the quantum vacuum, with the associated energy scale set by HØ, the present rate of expansion of the universe. However, this is quite inexplicable in the successful Standard Model (quantum field theory) of fundamental interactions, the characteristic energy scale of which is higher by a factor of 1044. So, while the standard cosmological model (called ΛCDM) describes the observational data well, its main component, dark energy, has no physical basis.

    Testing foundational assumptions

    This is what motivated the researchers to re-examine its underlying assumptions. Professor Sarkar says: “When the foundations of today’s standard cosmological model were laid a hundred years ago, there was no data. We didn’t even know then that we live in a galaxy – just one among a hundred billion others. Now that we do have data, we can, and should, test these foundational assumptions since a lot rests on them – in particular the inference that dark energy dominates the Universe.”

    In fact, the Universe today is manifestly not homogeneous and isotropic. Astronomical surveys reveal a filamentary structure of galaxies, clusters of galaxies, and superclusters of clusters … and this ‘cosmic web’ extends to the deepest scales currently probed of about 2 billion light years.

    The conventional wisdom is that, while clumpy on small scales, the distribution of matter becomes homogeneous when averaged on scales larger than about 300 million light years. The Hubble expansion is smooth and isotropic on large scales, while on small scales the gravitational effect of inhomogeneities give rise to ‘peculiar’ velocities eg our nearest neighbor the Andromeda galaxy is not receding in the Hubble flow – rather it is falling towards us.

    Back in 1966, the cosmologist Dennis Sciama noted that because of this, the cosmic microwave background (CMB) radiation from the Big Bang could not be uniform on the sky.

    It must exhibit a ‘dipole anisotropy’ ie appear hotter in the direction of our local motion and colder in the opposite direction. This was indeed found soon afterwards and is attributed to our motion at about 370 km/s towards a particular direction (in the constellation of Crater). Accordingly, a special relativistic ‘boost’ is applied to all cosmological data (redshifts, apparent magnitudes etc) to transform them to the reference frame in which the universe is isotropic, since it is in this ‘cosmic rest frame’ that the Friedmann-Lemaître equations of the standard cosmological model hold. Application of these equations to the corrected data then indicates that the Hubble expansion rate is accelerating, as if driven by Einstein’s Cosmological Constant “L”, aka dark energy.

    The cosmological principle

    How can we check if this is true? If the dipole anisotropy in the CMB is due to our motion, then there must be a similar dipole in the sky distribution of all cosmologically distant sources. This is due to ‘aberration’ because of the finite speed of light – as was recognized by Oxford astronomer James Bradley in 1727, long before Albert Einstein’s formulation of the Special Theory of Relativity which predicts this effect. Such sources were first identified with radio telescopes; the relativist George Ellis and radio astronomer John Baldwin noted in 1984 that with a uniform sky map of at least a few hundred thousand such sources, this dipole could be measured and compared with the standard expectation. It was not however until this millennium that the first such data became available – the NRAO VLA Sky Survey (NVSS) catalogue of radio sources.

    The dipole amplitude turned out to be higher than expected, although its direction was consistent with that of the CMB. However, the uncertainties were large, so the significance of the discrepancy was not compelling. Two years ago, the present team of researchers upped the stakes by analyzing a bigger catalogue of 1.4 million quasars mapped by NASA’s Wide-field Infrared Explorer (WISE).

    They found a similar discrepancy but at much higher significance. Dr von Hausegger comments: “If distant sources are not isotropic in the rest frame in which the CMB is isotropic, it implies a violation of the cosmological principle … which means going back to square one! So, we must now seek corroborating evidence to understand what causes this unexpected result.”

    In their recent paper, the researchers have addressed this by performing a joint analysis of the NVSS and WISE catalogues after performing various detailed checks to demonstrate their suitability for the purpose. These catalogues are systematically independent and have almost no shared objects so this is equivalent to performing two independent experiments. The dipoles in the two catalogues, made at widely different wavelengths, are found to be consistent with each other. The consistency of the two dipoles improves upon boosting to the frame in which the CMB is isotropic (assuming its dipole to be kinematic in origin), which suggests that cosmologically distant radio galaxies and quasars may have an intrinsic anisotropy in this frame. The joint significance of the discrepancy between the rest frames of radiation and matter now exceeds 5σ (ie a probability of less than 1 in 3.5 million of being a fluke). “This issue can no longer be ignored,” comments Professor Sarkar. “The validity of the FLRW metric itself is now in question!”

    Potential paradigm-changing finding

    New data with which to check this potentially paradigm-changing finding will soon come from the Legacy Survey of Space and Time (LSST) to be carried out at the Vera C Rubin Observatory in Chile.

    Oxford Physics is closely involved in this project, along with many other institutions in the UK and all over the world. Professor Ian Shipsey who has been a member of LSST since 2008, is excited about the prospect of carrying out fundamental cosmological tests. ‘As a particle physicist, I am acutely aware that the foundations of the Standard Model of particle physics are constantly under scrutiny.

    One of the reasons I joined LSST, and have worked for so long on it, is precisely to enable powerful tests of the foundations of the standard cosmological model,’ he says. To this end, Dr Hausegger and Professor Sarkar are leading projects in the LSST Dark Energy Science Collaboration to use the forthcoming data to test the homogeneity and isotropy of the Universe. ‘We will soon know if the standard cosmological model and the inference of dark energy are indeed valid,’ concludes Professor Sarkar.

    Science paper:
    The Astrophysical Journal Letters

    See the full article here.

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    Please help promote STEM in your local schools.

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    U Oxford campus

    The University of Oxford

    1
    Universitas Oxoniensis

    The University of Oxford [a.k.a. The Chancellor, Masters and Scholars of the University of Oxford] is a collegiate research university in Oxford, England. There is evidence of teaching as early as 1096, making it the oldest university in the English-speaking world and the world’s second-oldest university in continuous operation. It grew rapidly from 1167 when Henry II banned English students from attending the University of Paris [Université de Paris] (FR). After disputes between students and Oxford townsfolk in 1209, some academics fled north-east to Cambridge where they established what became the University of Cambridge (UK). The two English ancient universities share many common features and are jointly referred to as Oxbridge.

    The university is made up of thirty-nine semi-autonomous constituent colleges, six permanent private halls, and a range of academic departments which are organized into four divisions. All the colleges are self-governing institutions within the university, each controlling its own membership and with its own internal structure and activities. All students are members of a college. It does not have a main campus, and its buildings and facilities are scattered throughout the city centre. Undergraduate teaching at Oxford consists of lectures, small-group tutorials at the colleges and halls, seminars, laboratory work and occasionally further tutorials provided by the central university faculties and departments. Postgraduate teaching is provided predominantly centrally.

    Oxford operates the world’s oldest university museum, as well as the largest university press in the world and the largest academic library system nationwide. In the fiscal year ending 31 July 2019, the university had a total income of £2.45 billion, of which £624.8 million was from research grants and contracts.

    Oxford has educated a wide range of notable alumni, including 28 prime ministers of the United Kingdom and many heads of state and government around the world. As of October 2020, 72 Nobel Prize laureates, 3 Fields Medalists, and 6 Turing Award winners have studied, worked, or held visiting fellowships at the University of Oxford, while its alumni have won 160 Olympic medals. Oxford is the home of numerous scholarships, including the Rhodes Scholarship, one of the oldest international graduate scholarship programmes.

    The University of Oxford’s foundation date is unknown. It is known that teaching at Oxford existed in some form as early as 1096, but it is unclear when a university came into being.

    It grew quickly from 1167 when English students returned from The University of Paris-Sorbonne [Université de Paris-Sorbonne](FR). The historian Gerald of Wales lectured to such scholars in 1188, and the first known foreign scholar, Emo of Friesland, arrived in 1190. The head of the university had the title of chancellor from at least 1201, and the masters were recognized as a universitas or corporation in 1231. The university was granted a royal charter in 1248 during the reign of King Henry III.

    The students associated together on the basis of geographical origins, into two ‘nations’, representing the North (northerners or Boreales, who included the English people from north of the River Trent and the Scots) and the South (southerners or Australes, who included English people from south of the Trent, the Irish and the Welsh). In later centuries, geographical origins continued to influence many students’ affiliations when membership of a college or hall became customary in Oxford. In addition, members of many religious orders, including Dominicans, Franciscans, Carmelites and Augustinians, settled in Oxford in the mid-13th century, gained influence and maintained houses or halls for students. At about the same time, private benefactors established colleges as self-contained scholarly communities. Among the earliest such founders were William of Durham, who in 1249 endowed University College, and John Balliol, father of a future King of Scots; Balliol College bears his name. Another founder, Walter de Merton, a Lord Chancellor of England and afterwards Bishop of Rochester, devised a series of regulations for college life. Merton College thereby became the model for such establishments at Oxford, as well as at the University of Cambridge. Thereafter, an increasing number of students lived in colleges rather than in halls and religious houses.

    In 1333–1334, an attempt by some dissatisfied Oxford scholars to found a new university at Stamford, Lincolnshire, was blocked by the universities of Oxford and Cambridge petitioning King Edward III. Thereafter, until the 1820s, no new universities were allowed to be founded in England, even in London; thus, Oxford and Cambridge had a duopoly, which was unusual in large western European countries.

    The new learning of the Renaissance greatly influenced Oxford from the late 15th century onwards. Among university scholars of the period were William Grocyn, who contributed to the revival of Greek language studies, and John Colet, the noted biblical scholar.

    With the English Reformation and the breaking of communion with the Roman Catholic Church, recusant scholars from Oxford fled to continental Europe, settling especially at the University of Douai. The method of teaching at Oxford was transformed from the medieval scholastic method to Renaissance education, although institutions associated with the university suffered losses of land and revenues. As a centre of learning and scholarship, Oxford’s reputation declined in the Age of Enlightenment; enrollments fell and teaching was neglected.

    In 1636, William Laud, the chancellor and Archbishop of Canterbury, codified the university’s statutes. These, to a large extent, remained its governing regulations until the mid-19th century. Laud was also responsible for the granting of a charter securing privileges for The University Press, and he made significant contributions to the Bodleian Library, the main library of the university. From the beginnings of the Church of England as the established church until 1866, membership of the church was a requirement to receive the BA degree from the university and “dissenters” were only permitted to receive the MA in 1871.

    The university was a centre of the Royalist party during the English Civil War (1642–1649), while the town favored the opposing Parliamentarian cause. From the mid-18th century onwards, however, the university took little part in political conflicts.

    Wadham College, founded in 1610, was the undergraduate college of Sir Christopher Wren. Wren was part of a brilliant group of experimental scientists at Oxford in the 1650s, the Oxford Philosophical Club, which included Robert Boyle and Robert Hooke. This group held regular meetings at Wadham under the guidance of the college’s Warden, John Wilkins, and the group formed the nucleus that went on to found the Royal Society.

    Before reforms in the early 19th century, the curriculum at Oxford was notoriously narrow and impractical. Sir Spencer Walpole, a historian of contemporary Britain and a senior government official, had not attended any university. He said, “Few medical men, few solicitors, few persons intended for commerce or trade, ever dreamed of passing through a university career.” He quoted the Oxford University Commissioners in 1852 stating: “The education imparted at Oxford was not such as to conduce to the advancement in life of many persons, except those intended for the ministry.” Nevertheless, Walpole argued:

    “Among the many deficiencies attending a university education there was, however, one good thing about it, and that was the education which the undergraduates gave themselves. It was impossible to collect some thousand or twelve hundred of the best young men in England, to give them the opportunity of making acquaintance with one another, and full liberty to live their lives in their own way, without evolving in the best among them, some admirable qualities of loyalty, independence, and self-control. If the average undergraduate carried from university little or no learning, which was of any service to him, he carried from it a knowledge of men and respect for his fellows and himself, a reverence for the past, a code of honor for the present, which could not but be serviceable. He had enjoyed opportunities… of intercourse with men, some of whom were certain to rise to the highest places in the Senate, in the Church, or at the Bar. He might have mixed with them in his sports, in his studies, and perhaps in his debating society; and any associations which he had this formed had been useful to him at the time, and might be a source of satisfaction to him in after life.”

    Out of the students who matriculated in 1840, 65% were sons of professionals (34% were Anglican ministers). After graduation, 87% became professionals (59% as Anglican clergy). Out of the students who matriculated in 1870, 59% were sons of professionals (25% were Anglican ministers). After graduation, 87% became professionals (42% as Anglican clergy).

    M. C. Curthoys and H. S. Jones argue that the rise of organized sport was one of the most remarkable and distinctive features of the history of the universities of Oxford and Cambridge in the late 19th and early 20th centuries. It was carried over from the athleticism prevalent at the public schools such as Eton, Winchester, Shrewsbury, and Harrow.

    All students, regardless of their chosen area of study, were required to spend (at least) their first year preparing for a first-year examination that was heavily focused on classical languages. Science students found this particularly burdensome and supported a separate science degree with Greek language study removed from their required courses. This concept of a Bachelor of Science had been adopted at other European universities (The University of London (UK) had implemented it in 1860) but an 1880 proposal at Oxford to replace the classical requirement with a modern language (like German or French) was unsuccessful. After considerable internal wrangling over the structure of the arts curriculum, in 1886 the “natural science preliminary” was recognized as a qualifying part of the first-year examination.

    At the start of 1914, the university housed about 3,000 undergraduates and about 100 postgraduate students. During the First World War, many undergraduates and fellows joined the armed forces. By 1918 virtually all fellows were in uniform, and the student population in residence was reduced to 12 per cent of the pre-war total. The University Roll of Service records that, in total, 14,792 members of the university served in the war, with 2,716 (18.36%) killed. Not all the members of the university who served in the Great War were on the Allied side; there is a remarkable memorial to members of New College who served in the German armed forces, bearing the inscription, ‘In memory of the men of this college who coming from a foreign land entered into the inheritance of this place and returning fought and died for their country in the war 1914–1918’. During the war years the university buildings became hospitals, cadet schools and military training camps.

    Reforms

    Two parliamentary commissions in 1852 issued recommendations for Oxford and Cambridge. Archibald Campbell Tait, former headmaster of Rugby School, was a key member of the Oxford Commission; he wanted Oxford to follow the German and Scottish model in which the professorship was paramount. The commission’s report envisioned a centralized university run predominantly by professors and faculties, with a much stronger emphasis on research. The professional staff should be strengthened and better paid. For students, restrictions on entry should be dropped, and more opportunities given to poorer families. It called for an enlargement of the curriculum, with honors to be awarded in many new fields. Undergraduate scholarships should be open to all Britons. Graduate fellowships should be opened up to all members of the university. It recommended that fellows be released from an obligation for ordination. Students were to be allowed to save money by boarding in the city, instead of in a college.

    The system of separate honor schools for different subjects began in 1802, with Mathematics and Literae Humaniores. Schools of “Natural Sciences” and “Law, and Modern History” were added in 1853. By 1872, the last of these had split into “Jurisprudence” and “Modern History”. Theology became the sixth honor school. In addition to these B.A. Honors degrees, the postgraduate Bachelor of Civil Law (B.C.L.) was, and still is, offered.

    The mid-19th century saw the impact of the Oxford Movement (1833–1845), led among others by the future Cardinal John Henry Newman. The influence of the reformed model of German universities reached Oxford via key scholars such as Edward Bouverie Pusey, Benjamin Jowett and Max Müller.

    Administrative reforms during the 19th century included the replacement of oral examinations with written entrance tests, greater tolerance for religious dissent, and the establishment of four women’s colleges. Privy Council decisions in the 20th century (e.g. the abolition of compulsory daily worship, dissociation of the Regius Professorship of Hebrew from clerical status, diversion of colleges’ theological bequests to other purposes) loosened the link with traditional belief and practice. Furthermore, although the university’s emphasis had historically been on classical knowledge, its curriculum expanded during the 19th century to include scientific and medical studies. Knowledge of Ancient Greek was required for admission until 1920, and Latin until 1960.

    The University of Oxford began to award doctorates for research in the first third of the 20th century. The first Oxford D.Phil. in mathematics was awarded in 1921.

    The mid-20th century saw many distinguished continental scholars, displaced by Nazism and communism, relocating to Oxford.

    The list of distinguished scholars at the University of Oxford is long and includes many who have made major contributions to politics, the sciences, medicine, and literature. As of October 2020, 72 Nobel laureates and more than 50 world leaders have been affiliated with the University of Oxford.

    To be a member of the university, all students, and most academic staff, must also be a member of a college or hall. There are thirty-nine colleges of the University of Oxford (including Reuben College, planned to admit students in 2021) and six permanent private halls (PPHs), each controlling its membership and with its own internal structure and activities. Not all colleges offer all courses, but they generally cover a broad range of subjects.

    The colleges are:

    All-Souls College
    Balliol College
    Brasenose College
    Christ Church College
    Corpus-Christi College
    Exeter College
    Green-Templeton College
    Harris-Manchester College
    Hertford College
    Jesus College
    Keble College
    Kellogg College
    Lady-Margaret-Hall
    Linacre College
    Lincoln College
    Magdalen College
    Mansfield College
    Merton College
    New College
    Nuffield College
    Oriel College
    Pembroke College
    Queens College
    Reuben College
    St-Anne’s College
    St-Antony’s College
    St-Catherines College
    St-Cross College
    St-Edmund-Hall College
    St-Hilda’s College
    St-Hughs College
    St-John’s College
    St-Peters College
    Somerville College
    Trinity College
    University College
    Wadham College
    Wolfson College
    Worcester College

    The permanent private halls were founded by different Christian denominations. One difference between a college and a PPH is that whereas colleges are governed by the fellows of the college, the governance of a PPH resides, at least in part, with the corresponding Christian denomination. The six current PPHs are:

    Blackfriars
    Campion Hall
    Regent’s Park College
    St Benet’s Hall
    St-Stephen’s Hall
    Wycliffe Hall

    The PPHs and colleges join as the Conference of Colleges, which represents the common concerns of the several colleges of the university, to discuss matters of shared interest and to act collectively when necessary, such as in dealings with the central university. The Conference of Colleges was established as a recommendation of the Franks Commission in 1965.

    Teaching members of the colleges (i.e., fellows and tutors) are collectively and familiarly known as dons, although the term is rarely used by the university itself. In addition to residential and dining facilities, the colleges provide social, cultural, and recreational activities for their members. Colleges have responsibility for admitting undergraduates and organizing their tuition; for graduates, this responsibility falls upon the departments. There is no common title for the heads of colleges: the titles used include Warden, Provost, Principal, President, Rector, Master and Dean.

    Oxford is regularly ranked within the top 5 universities in the world and is currently ranked first in the world in the Times Higher Education World University Rankings, as well as the Forbes’s World University Rankings. It held the number one position in The Times Good University Guide for eleven consecutive years, and the medical school has also maintained first place in the “Clinical, Pre-Clinical & Health” table of The Times Higher Education World University Rankings for the past seven consecutive years. In 2021, it ranked sixth among the universities around the world by SCImago Institutions Rankings. The Times Higher Education has also recognised Oxford as one of the world’s “six super brands” on its World Reputation Rankings, along with The University of California-Berkeley, The University of Cambridge (UK), Harvard University, The Massachusetts Institute of Technology, and Stanford University. The university is fifth worldwide on the US News ranking. Its Saïd Business School came 13th in the world in The Financial Times Global MBA Ranking.
    Oxford was ranked ninth in the world in 2015 by The Nature Index, which measures the largest contributors to papers published in 82 leading journals. It is ranked fifth best university worldwide and first in Britain for forming CEOs according to The Professional Ranking World Universities, and first in the UK for the quality of its graduates as chosen by the recruiters of the UK’s major companies.

    In the 2018 Complete University Guide, all 38 subjects offered by Oxford rank within the top 10 nationally meaning Oxford was one of only two multi-faculty universities (along with Cambridge) in the UK to have 100% of their subjects in the top 10. Computer Science, Medicine, Philosophy, Politics and Psychology were ranked first in the UK by the guide.

    According to The QS World University Rankings by Subject, the University of Oxford also ranks as number one in the world for four Humanities disciplines: English Language and Literature, Modern Languages, Geography, and History. It also ranks second globally for Anthropology, Archaeology, Law, Medicine, Politics & International Studies, and Psychology.

     
  • richardmitnick 1:15 pm on July 18, 2022 Permalink | Reply
    Tags: "Can Shock Waves Create the Conditions for Molecule Formation?", , , , , , , Interstellar chemistry, Radio Astronomy,   

    From AAS NOVA: “Can Shock Waves Create the Conditions for Molecule Formation?” 

    AASNOVA

    From AAS NOVA

    18 July 2022
    Kerry Hensley

    1
    This infrared image from the Spitzer Space Telescope shows the dark, dusty cloud Lynds 1157, which hosts young protostars. [NASA/JPL-Caltech/UIUC]

    The dark, dusty clouds surrounding young, hot protostars are the sites of molecule formation. What can new radio observations tell us about the potential for molecule formation in the shocked surroundings of a nearby protostar system?

    Making Molecules

    2
    A visible-light image of the interstellar dark cloud Lynds 1157. Infrared or radio observations are needed to reveal the young stars hidden by the dust. [NASA/JPL-Caltech/AURA]

    Over the past century, astronomers have discovered more than a hundred kinds of molecules in space. Exactly how these molecules form and survive in the cold, tenuous gas of the interstellar medium is an active area of research. One of several ways that molecules are thought to form is in the wake of a shock wave, which condenses and warms the interstellar medium, helping lone atoms link up in the vastness of space.

    Shock waves can be produced by outflows from newly forming stars called protostars, which are still wrapped in dense clouds of gas and dust. Luckily, infrared and radio observations allow us to draw back this dusty curtain and peer into the birthplaces of young stars and watch as they collect gas and shoot out jets of material. In a new publication, a team led by Siyi Feng (冯思轶) from Xiamen University presents new radio data that probes the surroundings of a young protostellar system at the heart of the dark cloud Lynds 1157 — one of the best places to study how shocks impact interstellar chemistry.

    3
    Example maps of an outflowing jet from Lynds 1157 in two emission lines of ammonia. The shocks are located at the places labeled B0, B1, and B2, while smaller structures are labeled with additional letters. The protobinary is labeled “mm.” [Adapted from Feng et al. 2022]

    Peering at Protostars

    Previous observations of Lynds 1157 have shown that the region hosts organic molecules like methanol and cyanoacetylene — a clear sign of ongoing interstellar chemistry. What makes the region especially interesting is the series of shocks that have formed along a jet that flows outward from the central source, which is likely a protobinary system. Observations show that the outermost shock is 1,000 years old, while the inner shocks are younger, allowing us to study how the temperature and density of the gas changed over time as the shocks passed through.

    Using the Karl G. Jansky Very Large Array, Feng and collaborators observed emission lines of ammonia (NH3) to make high-resolution maps of Lynds 1157 and measure how the temperature and density of the gas vary throughout the cloud.

    Studying Shocks

    4
    Maps of the mean temperature (left), density (center), and ratio of ammonia molecules in an excited state to those in an unexcited state (right). [Adapted from Feng et al. 2022]

    The ammonia emission lines trace the jet as it moves outward from the central protobinary, and the observations show that the gas is warmest close to the protobinary, cooler farther out along the jet, and densest at the locations of the shocks. And at the locations of the shocks, the team found evidence for ammonia molecules in an excited state, a clear indication that the gas has been heated by the shocks.

    The team’s observations show that the passage of shocks heated and compressed the gas, and that as the shocks moved outward, the gas cooled. This illustrates that shocks can provide the warm, dense environment needed for molecules to form. The measurements made in this work should enable detailed chemical modeling, allowing for an even better understanding of how shocks have transformed the gas around these young protostars and paved the way for molecule formation.

    Citation

    A Detailed Temperature Map of the Archetypal Protostellar Shocks in L1157, S. Feng et al 2022 ApJL 933 L35.
    https://iopscience.iop.org/article/10.3847/2041-8213/ac75d7/pdf

    See the full article here .


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    1

    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

    The society was founded in 1899 through the efforts of George Ellery Hale. The constitution of the group was written by Hale, George Comstock, Edward Morley, Simon Newcomb and Edward Charles Pickering. These men, plus four others, were the first Executive Council of the society; Newcomb was the first president. The initial membership was 114. The AAS name of the society was not finally decided until 1915, previously it was the “Astronomical and Astrophysical Society of America”. One proposed name that preceded this interim name was “American Astrophysical Society”.

    The AAS today has over 7,000 members and six divisions – the Division for Planetary Sciences (1968); the Division on Dynamical Astronomy (1969); the High Energy Astrophysics Division (1969); the Solar Physics Division (1969); the Historical Astronomy Division (1980); and the Laboratory Astrophysics Division (2012). The membership includes physicists, mathematicians, geologists, engineers and others whose research interests lie within the broad spectrum of subjects now comprising contemporary astronomy.

    In 2019 three AAS members were selected into the tenth anniversary class of TED Fellows.

    The AAS established the AAS Fellows program in 2019 to “confer recognition upon AAS members for achievement and extraordinary service to the field of astronomy and the American Astronomical Society.” The inaugural class was designated by the AAS Board of Trustees and includes an initial group of 232 Legacy Fellows.

     
  • richardmitnick 7:57 pm on July 11, 2022 Permalink | Reply
    Tags: "Radio and microwaves reveal true nature of dark galaxies in the early Universe", , , , , , Radio Astronomy,   

    From The Niels Bohr Institute [Niels Bohr Institutet] (DK): “Radio and microwaves reveal true nature of dark galaxies in the early Universe” 

    Niels Bohr Institute bloc

    From The Niels Bohr Institute [Niels Bohr Institutet] (DK)

    at

    University of Copenhagen [Københavns Universitet] [UCPH] (DK)

    11 July 2022

    Galaxy Formation: Utilizing multiple radio telescopes across the world, a team of astronomers from the Cosmic Dawn Center, Copenhagen, have discovered several galaxies in the early Universe that, due to massive amounts of dust, were hidden from our sight. The observations allowed the team to measure the temperature and thickness of the dust, demonstrating that this type of galaxies contributed significantly to the total star formation when the Universe was only 1/10 of its current age.

    1
    Artist’s impression of a dust-enshrouded starburst (credit: ESO/M. Kornmesser). Artist’s impression of a dust-enshrouded starburst (Credit: M. Kornmesser/ESO).

    Measuring the rate at which stars are born in galaxies across cosmic time is one of the fundamental ways astronomers describe the properties and the evolution of galaxies.

    Various methods are used to estimate this so-called “star formation rate”, typically depending on the light that is emitted from either the stars, or from matter that is illuminated by the stars.

    Cosmic dust

    However, the stars that are formed tend, in turn, to create dust — particles made of heavy elements such as carbon, silicon, oxygen, and iron. The dust appears as thick clouds in the space between the stars, possibly hiding the stars completely from our eyes.

    This makes it difficult to get a census of the star formation rate especially in young, “starburst” galaxies, where the dust has not yet had the time to disperse far from the compact sites of star formation.

    As the dust is heated by the stars, it begins to glow in long-wavelength, infrared light which, although invisible to the human eye, may be detected by telescopes designed to observe these wavelengths.

    But for the most compact, dust-enshrouded starbursts, we only see the surface of the clouds. These galaxies are invisible not only at the “humanly perceivable”, optical wavelengths, but also in the beginning of the infrared spectrum, utterly dark even to the Hubble Space Telescope.

    Galaxies on the Radio

    A team of astronomers — led by Shuowen Jin (靳硕文), Marie Curie postdoc fellow at the Cosmic Dawn Center, and including several other DAWNers — therefore decided to take a look at the early Universe at even longer wavelengths, using the radio/microwave antennae at two of the world’s largest radio observatories, the Atacama Large Millimeter Array (ALMA) in Chile, and the Northern Extended Millimeter Array (NOEMA) in France.

    2
    Six different views of the same galaxy (ID12646), seen less than a billion years after the Big Bang, at progressively longer wavelengths. The two first images show — or rather do not show — the galaxy in the near-infrared; the galaxy is completely invisible. Only when looking at the longer wavelengths is the galaxy revealed (credit: Shuowen Jin / Peter Laursen).

    Together with observations of the same field on the sky acquired with other radio telescopes, Jin’s observations revealed a population of compact starburst galaxies, cloaked in extremely thick dust clouds.

    Piercing through the clouds

    The radio- and microwave observations allowed the astronomers to measure the star formation rate and the temperature of the dust.

    “In these epochs, 1–2 billion years after the Big Bang, galaxies like these contributed significantly to the total star formation rate of the Universe, but pass unnoticed in optical and near-infrared observations,” says Shuowen Jin.

    The study explains why these galaxies are so dark in optical and infrared: “Because the dust clouds are so thick and dense, optical and near-infrared light cannot travel through. Even the far-infrared light is partially absorbed,” Shuowen Jin explains.

    The observations reveal not only dust, but also monoxide molecules (CO), mixed within the clouds. The light emitted by CO can help astronomers probe another important quantity of galaxies, namely the mass of all the gas in the galaxy. However, one of the key results of the work of Jin and his collaborators is that the standard way of inferring gas masses from CO emission is erroneous:

    The observed light is emitted from the surfaces of the dusty clouds. Typical models do not consider that light is blocked inside the clouds, changing its wavelength before it escapes. Taking this effect into account has rather drastic implications:

    “Our model accounts for the fact that even the infrared light does not escape directly from the center of the dust clouds. This shows us that previous estimates of gas masses have been overestimated by a factor of 2–3 in compact, dusty, star-forming galaxies,” Shuowen Jin explains.

    The study has just been accepted for publication in Astronomy & Astrophysics.

    See the full article here .


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    Niels Bohr Institute Campus

    The Niels Bohr Institutet (DK) is a research institute of the Københavns Universitet [UCPH] (DK). The research of the institute spans astronomy, geophysics, nanotechnology, particle physics, quantum mechanics and biophysics.

    The Institute was founded in 1921, as the Institute for Theoretical Physics of the Københavns Universitet [UCPH] (DK), by the Danish theoretical physicist Niels Bohr, who had been on the staff of the University of Copenhagen since 1914, and who had been lobbying for its creation since his appointment as professor in 1916. On the 80th anniversary of Niels Bohr’s birth – October 7, 1965 – the Institute officially became The Niels Bohr Institutet (DK). Much of its original funding came from the charitable foundation of the Carlsberg brewery, and later from the Rockefeller Foundation.

    During the 1920s, and 1930s, the Institute was the centre of the developing disciplines of atomic physics and quantum physics. Physicists from across Europe (and sometimes further abroad) often visited the Institute to confer with Bohr on new theories and discoveries. The Copenhagen interpretation of quantum mechanics is named after work done at the Institute during this time.

    On January 1, 1993 the institute was fused with the Astronomic Observatory, the Ørsted Laboratory and the Geophysical Institute. The new resulting institute retained the name Niels Bohr Institutet (DK).

    Københavns Universitet (UCPH) (DK) is the oldest university and research institution in Denmark. Founded in 1479 as a studium generale, it is the second oldest institution for higher education in Scandinavia after Uppsala University (1477). The university has 23,473 undergraduate students, 17,398 postgraduate students, 2,968 doctoral students and over 9,000 employees. The university has four campuses located in and around Copenhagen, with the headquarters located in central Copenhagen. Most courses are taught in Danish; however, many courses are also offered in English and a few in German. The university has several thousands of foreign students, about half of whom come from Nordic countries.

    The university is a member of the International Alliance of Research Universities (IARU), along with University of Cambridge (UK), Yale University , The Australian National University (AU), and University of California-Berkeley , amongst others. The 2016 Academic Ranking of World Universities ranks the University of Copenhagen as the best university in Scandinavia and 30th in the world, the 2016-2017 Times Higher Education World University Rankings as 120th in the world, and the 2016-2017 QS World University Rankings as 68th in the world. The university has had 9 alumni become Nobel laureates and has produced one Turing Award recipient.

     
  • richardmitnick 8:00 am on July 8, 2022 Permalink | Reply
    Tags: "What is the electromagnetic spectrum?", , , From radio waves to gamma rays most of the light in the universe is-in fact-invisible to us., Fundamental properties of the spectrum: frequency measured in hertz (Hz); wavelength: the distance from the peak of one wave to the peak of the next., , Our brain interprets the various wavelengths of light as different colors., , , Radio Astronomy, , , Space based microwave telescopes, , , The electromagnetic waves your eyes detect – visible light – oscillate between 400 and 790 terahertz (THz)., The larger the frequency the smaller the wavelength and vice versa.   

    From “EarthSky” : “What is the electromagnetic spectrum?” 

    1

    From “EarthSky”

    July 8, 2022

    1
    The electromagnetic spectrum is a wide range of light; most of which we can’t see with our eyes. Here are the colors that make up the visible part of the spectrum. Image via Shutterstock.

    The electromagnetic spectrum

    When you think of light, you probably think of what your eyes can see. However, the light our human eyes can detect is only a sliver of the total amount of light that’s out there. The electromagnetic spectrum is the term scientists use to describe the entire range of light that exists. From radio waves to gamma rays most of the light in the universe is-in fact-invisible to us.

    Light is a wave of alternating electric and magnetic fields. The propagation of light isn’t much different than waves crossing an ocean. Like any other wave, light has a few fundamental properties that describe it. For example, one is its frequency measured in hertz (Hz), which counts the number of waves that pass by a point in one second. Another closely related property is its wavelength: the distance from the peak of one wave to the peak of the next. In fact, these two attributes are inversely related. The larger the frequency the smaller the wavelength and vice versa.

    2
    You can remember the order of the colors in the visible spectrum with the mnemonic ROY G BV. Image via University of Tennessee.

    Our eyes see visible light

    The electromagnetic waves your eyes detect – visible light – oscillate between 400 and 790 terahertz (THz). To put it another way, that’s several hundred trillion times a second. As an illustration, the wavelengths are roughly the size of a large virus: 390 – 750 nanometers (1 nanometer = 1 billionth of a meter; a meter is about 39 inches long). Our brain interprets the various wavelengths of light as different colors. For example, red has the longest wavelength, and violet the shortest. When we pass sunlight through a prism, we see that it’s actually composed of many wavelengths of light. The prism creates a rainbow by redirecting each wavelength out at a slightly different angle.

    3
    The entire electromagnetic spectrum is much more than just visible light. It encompasses a range of wavelengths of energy that our human eyes can’t see. Image via Wikimedia Commons.

    But light doesn’t stop at red or violet. Indeed, just like there are sounds we can’t hear, there is an enormous range of light that our eyes can’t detect. In general, the longer wavelengths come from the coolest and darkest regions of space. Meanwhile, the shorter wavelengths measure extremely energetic phenomena.

    The coolest part of the electromagnetic spectrum

    Astronomers use the entire electromagnetic spectrum to observe a variety of things. Radio waves and microwaves are the longest wavelengths and lowest energies of light. With this in mind, they are used to peer inside dense interstellar clouds and track the motion of cold, dark gas. Radio telescopes have been used to map the structure of our galaxy.

    Additionally, microwave telescopes are sensitive to the remnant glow of the Big Bang.

    3
    This image from the Very Large Baseline Array (VLBA) [above] shows what the galaxy Messier 33 would look like if you could see in radio waves. This image maps atomic hydrogen gas in the galaxy. The different colors map velocities in the gas: red shows gas moving away from us, blue is moving towards us. Image via NRAO/ AUI.

    Infrared telescopes excel at finding cool, dim stars, slicing through interstellar dust bands.

    Plus they even measure the temperatures of planets in other solar systems. The wavelengths of infrared light are long enough to navigate through clouds that would otherwise block our view. By using large infrared telescopes, astronomers peer through the dust lanes of our galaxy into the Milky Way’s core.

    4
    This image from the Hubble and Spitzer [above] space telescopes shows the central 300 light-years of our Milky Way galaxy, as we would see it if our eyes could see infrared energy. The image reveals massive star clusters and swirling gas clouds. Image via Q.D. Wang/ S. Stolovy/NASA JPL/ ESA/.

    Most stars emit visible light

    The majority of stars emit most of their electromagnetic energy as visible light, the tiny portion of the spectrum to which our eyes are sensitive. Because wavelength correlates with energy, the color of a star tells us how hot it is: red stars are coolest, blue are hottest. The coldest of stars emit hardly any visible light at all; they can only be seen with infrared telescopes.

    The more energetic ultraviolet light

    At wavelengths shorter than violet, we find the ultraviolet, or UV, light. You may be familiar with UV from its ability to give you a sunburn. Astronomers use it to hunt out the most energetic of stars and identify regions of star birth. When viewing distant galaxies with UV telescopes, most of the stars and gas disappear, and all the stellar nurseries pop into view.

    5
    A view of the spiral galaxy Messier 81 in the ultraviolet, made possible by the GALEX space observatory. The bright regions show stellar nurseries in the spiral arms. Image via NASA.

    Highest energy light: X-ray and Gamma Ray

    Beyond UV come the highest energies in the electromagnetic spectrum: X-rays and gamma rays. Our atmosphere blocks this light, so astronomers must rely on telescopes in space to see the X-ray and gamma ray universe. X-rays come from exotic neutron stars, the vortex of superheated material spiraling around a black hole. Or from diffuse clouds of gas in galactic clusters that are heated to many millions of degrees.

    Meanwhile, gamma rays – the shortest wavelength of light and deadly to humans – unveil violent events. These include supernova explosions, cosmic radioactive decay, and even the destruction of antimatter. Gamma ray bursts are among the most energetic singular events in the universe. They are a brief flickering of gamma ray light from distant galaxies when a star explodes and creates a black hole.

    6
    If you could see in X-rays, over long distances, you’d see this view of the nebula surrounding pulsar PSR B1509-58. This image is from the Chandra X-ray Observatory. Located 17,000 light-years away, the pulsar is the rapidly spinning remnant of a stellar core left behind after a supernova. Image via NASA.

    See the full article here .


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    Deborah Byrd created the EarthSky radio series in 1991 and founded EarthSky.org in 1994. Today, she serves as Editor-in-Chief of this website. She has won a galaxy of awards from the broadcasting and science communities, including having an asteroid named 3505 Byrd in her honor. A science communicator and educator since 1976, Byrd believes in science as a force for good in the world and a vital tool for the 21st century. “Being an EarthSky editor is like hosting a big global party for cool nature-lovers,” she says.

     
  • richardmitnick 4:26 pm on July 4, 2022 Permalink | Reply
    Tags: "University of Toronto Astro July Grad Student of the Month: Ariel Amaral, Ariel studies extragalactic magnetism using radio astronomy., , , , Radio Astronomy,   

    From The University of Toronto Dunlap Institute for Astronomy and Astrophysics (CA) : “University of Toronto Astro July Grad Student of the Month: Ariel Amaral 

    From The University of Toronto Dunlap Institute for Astronomy and Astrophysics (CA)

    At

    The University of Toronto(CA)

    7.4.22

    1
    Credit: Ariel Amaral.

    Ariel is a fifth-year PhD student at the University of Toronto. She works under the supervision of Professor Bryan Gaensler, and her thesis focuses on extra–galactic magnetic fields – from active galactic nuclei (AGN) to the intergalactic medium.

    Born and raised in Toronto (go Leafs go!), she received her Honours Bachelor of Science (specializing in Physics & Astronomy, and a minor in Mathematics) from the University of Toronto in 2017. During that time, she worked on projects analyzing the CMB as well as variable stars.

    When not doing research, you can find Ariel outside (usually hiking, camping, or backpacking), reading books about history, or watching hockey!
    ___________________________________________________________________
    How did you first become interested in Astronomy and Astrophysics?

    My first exposure to even thinking about being an astronomer came from watching Star Trek: The Original Series (in all its cheesy glory) with my dad from a super young age (I think I got hooked at like age 5). After that, I would read books on astronomy and try to learn anything I could. Then, my dad and I would visit the David Dunlap Observatory (DDO) in Richmond Hill and listen to lectures from astronomers about a wide range of topics. These outreach events that I attended really had an impact on me and my academic path. In high school, I officially decided I wanted to study astronomy and applied for the Physics and Astronomy Specialist program at U of T for my undergrad! And, here I am 10 years later.

    Can you tell us a little bit about your specific field of research?

    I study extragalactic magnetism using radio astronomy. Since magnetic fields are essentially invisible, we use radio polarimetry to detect magnetic fields from distant sources through the effect known as “Faraday rotation.” I recently completed a project that used a statistically significant sample of distant radio galaxies with Faraday rotation measurements to try to measure the magnetic fields present on the largest scales in the universe – the cosmic web. Currently, I’m looking at smaller scales and focusing on the magnetic fields within active galactic nuclei (AGN). The truth is, we know that magnetic fields play a huge role in AGN processes, but the specifics are still a bit of a mystery. However, I have new broadband polarized data observed with the Australia Compact Telescope Array (ATCA) on hundreds of AGN. I will be analyzing their magnetic fields (using Faraday rotation) to understand what’s going on in the general radio galaxy population, and quantify their magnetic properties.

    What’s the most exciting thing about your research?

    I think we’re at a really exciting time in radio astronomy; we’re about to witness a massive increase in the quantity and quality of the data that astronomers will be able to access. The precursor to the Square Kilometre Array (SKA), ASKAP, will essentially map the entire radio southern sky in full polarization, making it possible to understand extragalactic magnetism to a level we could not achieve with older, more limited data.

    I’m excited to explore the richness of data from the radio sky that is to come! I can just imagine all the incredible things we will be able to learn about magnetism in the next few years!

    What do you hope will be your next step, professionally?

    Right now, I know that I would really love to continue my research journey in astronomy with a post-doc position and, honestly, just have fun doing cool science for a few years. That’s something I’ll have to start applying for very soon. After a postdoc, my ambitions are very open-ended. I’m very interested in environmental conservation in Ontario and would love for my career path to somehow end up along those lines, but I don’t have a clear goal for right now. I’m just going to try to enjoy the journey over the next little while and not get too wrapped up in thinking about the more distant future.

    2
    An image of radio galaxy Hercules A. Radio galaxies host AGN (active galactic nuclei) and are primarily seen in the long-wavelength radio frequencies due to synchrotron emission. These galaxies usually contain an active central black hole that is actively “eating” surrounding matter. They also have well-formed radio jets and lobes that can be seen coming out of the central black hole. Credit: NASA.

    3
    These are three images of a distant radio galaxy 2207-5626, observed by the Australia Compact Telescope Array (ATCA) at radio frequencies used in Ariel’s research.

    This radio galaxy is much less resolved than Hercules A (image above), but you can still make out the radio jets and lobes in the image on the left. The central and right-most images show what the polarized light looks like from the radio galaxy – you can see dark and light patches where the lobes are located in the left-most image. Looking at the polarized light properties allows us to measure magnetic fields. Credit: Ariel Amaral.

    5
    This diagram depicts the process of “Faraday rotation,” a technique used to detect magnetic fields in distant astronomical objects. A distant radio galaxy emits polarized light; when this polarized light passes through a magnetic field, the polarization angle rotates. The amount of rotation the light’s polarization angle experiences is proportional to the magnetic field strength. Credit: Philipp P. Kronberg, Physics Today, December 2002. Edits by Ariel Amaral.

    See the full article here .


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    Please help promote STEM in your local schools.

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    Dunlap Institute campus

    The Dunlap Institute for Astronomy & Astrophysics (CA) at the University of Toronto (CA) is an endowed research institute with nearly 70 faculty, postdocs, students and staff, dedicated to innovative technology, ground-breaking research, world-class training, and public engagement. The research themes of its faculty and Dunlap Fellows span the Universe and include: optical, infrared and radio instrumentation; Dark Energy; large-scale structure; the Cosmic Microwave Background; the interstellar medium; galaxy evolution; cosmic magnetism; and time-domain science.

    The Dunlap Institute (CA), Department of Astronomy & Astrophysics (CA), Canadian Institute for Theoretical Astrophysics (CA), and Centre for Planetary Sciences (CA) comprise the leading centre for astronomical research in Canada, at the leading research university in the country, the University of Toronto (CA).

    The Dunlap Institute (CA) is committed to making its science, training and public outreach activities productive and enjoyable for everyone, regardless of gender, sexual orientation, disability, physical appearance, body size, race, nationality or religion.

    Our work is greatly enhanced through collaborations with the Department of Astronomy & Astrophysics (CA), Canadian Institute for Theoretical Astrophysics (CA), David Dunlap Observatory (CA), Ontario Science Centre (CA), Royal Astronomical Society of Canada (CA), the Toronto Public Library (CA), and many other partners.

    The The University of Toronto(CA) is a public research university in Toronto, Ontario, Canada, located on the grounds that surround Queen’s Park. It was founded by royal charter in 1827 as King’s College, the oldest university in the province of Ontario.

    Originally controlled by the Church of England, the university assumed its present name in 1850 upon becoming a secular institution.

    As a collegiate university, it comprises eleven colleges each with substantial autonomy on financial and institutional affairs and significant differences in character and history. The university also operates two satellite campuses located in Scarborough and Mississauga.

    The University of Toronto has evolved into Canada’s leading institution of learning, discovery and knowledge creation. We are proud to be one of the world’s top research-intensive universities, driven to invent and innovate.

    Our students have the opportunity to learn from and work with preeminent thought leaders through our multidisciplinary network of teaching and research faculty, alumni and partners.

    The ideas, innovations and actions of more than 560,000 graduates continue to have a positive impact on the world.

    Academically, The University of Toronto is noted for movements and curricula in literary criticism and communication theory, known collectively as the Toronto School.

    The university was the birthplace of insulin and stem cell research, and was the site of the first electron microscope in North America; the identification of the first black hole Cygnus X-1; multi-touch technology, and the development of the theory of NP-completeness.

    The university was one of several universities involved in early research of deep learning. It receives the most annual scientific research funding of any Canadian university and is one of two members of the Association of American Universities outside the United States, the other being McGill University [Université McGill] (CA) .

    The Varsity Blues are the athletic teams that represent the university in intercollegiate league matches, with ties to gridiron football, rowing and ice hockey. The earliest recorded instance of gridiron football occurred at University of Toronto’s University College in November 1861.

    The university’s Hart House is an early example of the North American student centre, simultaneously serving cultural, intellectual, and recreational interests within its large Gothic-revival complex.

    The University of Toronto has educated three Governors General of Canada, four Prime Ministers of Canada, three foreign leaders, and fourteen Justices of the Supreme Court. As of March 2019, ten Nobel laureates, five Turing Award winners, 94 Rhodes Scholars, and one Fields Medalist have been affiliated with the university.

    Early history

    The founding of a colonial college had long been the desire of John Graves Simcoe, the first Lieutenant-Governor of Upper Canada and founder of York, the colonial capital. As an University of Oxford (UK)-educated military commander who had fought in the American Revolutionary War, Simcoe believed a college was needed to counter the spread of republicanism from the United States. The Upper Canada Executive Committee recommended in 1798 that a college be established in York.

    On March 15, 1827, a royal charter was formally issued by King George IV, proclaiming “from this time one College, with the style and privileges of a University … for the education of youth in the principles of the Christian Religion, and for their instruction in the various branches of Science and Literature … to continue for ever, to be called King’s College.” The granting of the charter was largely the result of intense lobbying by John Strachan, the influential Anglican Bishop of Toronto who took office as the college’s first president. The original three-storey Greek Revival school building was built on the present site of Queen’s Park.

    Under Strachan’s stewardship, King’s College was a religious institution closely aligned with the Church of England and the British colonial elite, known as the Family Compact. Reformist politicians opposed the clergy’s control over colonial institutions and fought to have the college secularized. In 1849, after a lengthy and heated debate, the newly elected responsible government of the Province of Canada voted to rename King’s College as the University of Toronto and severed the school’s ties with the church. Having anticipated this decision, the enraged Strachan had resigned a year earlier to open Trinity College as a private Anglican seminary. University College was created as the nondenominational teaching branch of the University of Toronto. During the American Civil War the threat of Union blockade on British North America prompted the creation of the University Rifle Corps which saw battle in resisting the Fenian raids on the Niagara border in 1866. The Corps was part of the Reserve Militia lead by Professor Henry Croft.

    Established in 1878, the School of Practical Science was the precursor to the Faculty of Applied Science and Engineering which has been nicknamed Skule since its earliest days. While the Faculty of Medicine opened in 1843 medical teaching was conducted by proprietary schools from 1853 until 1887 when the faculty absorbed the Toronto School of Medicine. Meanwhile the university continued to set examinations and confer medical degrees. The university opened the Faculty of Law in 1887, followed by the Faculty of Dentistry in 1888 when the Royal College of Dental Surgeons became an affiliate. Women were first admitted to the university in 1884.

    A devastating fire in 1890 gutted the interior of University College and destroyed 33,000 volumes from the library but the university restored the building and replenished its library within two years. Over the next two decades a collegiate system took shape as the university arranged federation with several ecclesiastical colleges including Strachan’s Trinity College in 1904. The university operated the Royal Conservatory of Music from 1896 to 1991 and the Royal Ontario Museum from 1912 to 1968; both still retain close ties with the university as independent institutions. The University of Toronto Press was founded in 1901 as Canada’s first academic publishing house. The Faculty of Forestry founded in 1907 with Bernhard Fernow as dean was Canada’s first university faculty devoted to forest science. In 1910, the Faculty of Education opened its laboratory school, the University of Toronto Schools.

    World wars and post-war years

    The First and Second World Wars curtailed some university activities as undergraduate and graduate men eagerly enlisted. Intercollegiate athletic competitions and the Hart House Debates were suspended although exhibition and interfaculty games were still held. The David Dunlap Observatory in Richmond Hill opened in 1935 followed by the University of Toronto Institute for Aerospace Studies in 1949. The university opened satellite campuses in Scarborough in 1964 and in Mississauga in 1967. The university’s former affiliated schools at the Ontario Agricultural College and Glendon Hall became fully independent of the University of Toronto and became part of University of Guelph (CA) in 1964 and York University (CA) in 1965 respectively. Beginning in the 1980s reductions in government funding prompted more rigorous fundraising efforts.

    Since 2000

    In 2000 Kin-Yip Chun was reinstated as a professor of the university after he launched an unsuccessful lawsuit against the university alleging racial discrimination. In 2017 a human rights application was filed against the University by one of its students for allegedly delaying the investigation of sexual assault and being dismissive of their concerns. In 2018 the university cleared one of its professors of allegations of discrimination and antisemitism in an internal investigation after a complaint was filed by one of its students.

    The University of Toronto was the first Canadian university to amass a financial endowment greater than c. $1 billion in 2007. On September 24, 2020 the university announced a $250 million gift to the Faculty of Medicine from businessman and philanthropist James C. Temerty- the largest single philanthropic donation in Canadian history. This broke the previous record for the school set in 2019 when Gerry Schwartz and Heather Reisman jointly donated $100 million for the creation of a 750,000-square foot innovation and artificial intelligence centre.

    Research

    Since 1926 the University of Toronto has been a member of the Association of American Universities a consortium of the leading North American research universities. The university manages by far the largest annual research budget of any university in Canada with sponsored direct-cost expenditures of $878 million in 2010. In 2018 the University of Toronto was named the top research university in Canada by Research Infosource with a sponsored research income (external sources of funding) of $1,147.584 million in 2017. In the same year the university’s faculty averaged a sponsored research income of $428,200 while graduate students averaged a sponsored research income of $63,700. The federal government was the largest source of funding with grants from the Canadian Institutes of Health Research; the Natural Sciences and Engineering Research Council; and the Social Sciences and Humanities Research Council amounting to about one-third of the research budget. About eight percent of research funding came from corporations- mostly in the healthcare industry.

    The first practical electron microscope was built by the physics department in 1938. During World War II the university developed the G-suit- a life-saving garment worn by Allied fighter plane pilots later adopted for use by astronauts.Development of the infrared chemiluminescence technique improved analyses of energy behaviours in chemical reactions. In 1963 the asteroid 2104 Toronto was discovered in the David Dunlap Observatory (CA) in Richmond Hill and is named after the university. In 1972 studies on Cygnus X-1 led to the publication of the first observational evidence proving the existence of black holes. Toronto astronomers have also discovered the Uranian moons of Caliban and Sycorax; the dwarf galaxies of Andromeda I, II and III; and the supernova SN 1987A. A pioneer in computing technology the university designed and built UTEC- one of the world’s first operational computers- and later purchased Ferut- the second commercial computer after UNIVAC I. Multi-touch technology was developed at Toronto with applications ranging from handheld devices to collaboration walls. The AeroVelo Atlas which won the Igor I. Sikorsky Human Powered Helicopter Competition in 2013 was developed by the university’s team of students and graduates and was tested in Vaughan.

    The discovery of insulin at The University of Toronto in 1921 is considered among the most significant events in the history of medicine. The stem cell was discovered at the university in 1963 forming the basis for bone marrow transplantation and all subsequent research on adult and embryonic stem cells. This was the first of many findings at Toronto relating to stem cells including the identification of pancreatic and retinal stem cells. The cancer stem cell was first identified in 1997 by Toronto researchers who have since found stem cell associations in leukemia; brain tumors; and colorectal cancer. Medical inventions developed at Toronto include the glycaemic index; the infant cereal Pablum; the use of protective hypothermia in open heart surgery; and the first artificial cardiac pacemaker. The first successful single-lung transplant was performed at Toronto in 1981 followed by the first nerve transplant in 1988; and the first double-lung transplant in 1989. Researchers identified the maturation promoting factor that regulates cell division and discovered the T-cell receptor which triggers responses of the immune system. The university is credited with isolating the genes that cause Fanconi anemia; cystic fibrosis; and early-onset Alzheimer’s disease among numerous other diseases. Between 1914 and 1972 the university operated the Connaught Medical Research Laboratories- now part of the pharmaceutical corporation Sanofi-Aventis. Among the research conducted at the laboratory was the development of gel electrophoresis.

    The University of Toronto is the primary research presence that supports one of the world’s largest concentrations of biotechnology firms. More than 5,000 principal investigators reside within 2 kilometres (1.2 mi) from the university grounds in Toronto’s Discovery District conducting $1 billion of medical research annually. MaRS Discovery District is a research park that serves commercial enterprises and the university’s technology transfer ventures. In 2008, the university disclosed 159 inventions and had 114 active start-up companies. Its SciNet Consortium operates the most powerful supercomputer in Canada.

     
  • richardmitnick 4:24 pm on June 28, 2022 Permalink | Reply
    Tags: "A sanitizer in the galactic centre region", A long-term study of the chemical composition of Sgr B2 was started that took advantage of the high angular resolution and sensitivity provided by ALMA., An outstanding star forming region in our Galaxy where many molecules were detected in the past is Sagittarius B2 (Sgr B2)., , , , , , , Investigation of the chemical composition of Sgr B2 began more than 15 years ago with the IRAM 30-m telescope., Iso-propanol was observed in a “delivery room” of stars-the massive star-forming region Sagittarius B2 which is located near the centre of our Milky Way., One difficulty in the identification of organic molecules is the spectral confusion. Each molecule emits radiation at specific frequencies-its spectral "fingerprint"-known from laboratory measurements, Radio Astronomy, Thanks to ALMA's high angular resolution it was possible to isolate very narrow spectral lines-five times more narrow than the lines detected on larger scales with the IRAM 30-m radio telescope!, The "Cologne Database for Molecular Spectroscopy (CDMS)" provides spectroscopic data to detect these molecules contributed by many groups and has been instrumental in their detection in many cases., The ALMA observations have led to the identification of three new organic molecules., The bigger the molecule the more spectral lines at different frequencies it produces., The goal of the present work is to understand how organic molecules form in the interstellar medium., The latest result within this ALMA project is now the detection of propanol (C3H7OH)., The molecular cloud is the target of an extensive investigation of its chemical composition with the ALMA telescope., , The search for molecules in space has been going on for more than 50 years. To date astronomers have identified 276 molecules in the interstellar medium., To date astronomers have identified 276 molecules in the interstellar medium., With the advent of the Atacama Large Millimeter/submillimeter Array (ALMA) ten years ago it became possible to go beyond what could be achieved toward Sgr B2 with a single-dish telescope.   

    From The MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE): “A sanitizer in the galactic centre region” 

    From The MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie](DE)

    June 28, 2022

    Dr. Norbert Junkes
    Press and public relations
    Max Planck Institute for Radio Astronomy, Bonn
    +49 2 28525-399
    njunkes@mpifr-bonn.mpg.de

    Dr. Arnaud Belloche
    Max Planck Institute for Radio Astronomy, Bonn
    +49 228 525-376
    belloche@mpifr-bonn.mpg.de

    Prof. Dr. Karl M. Menten
    Director at the Institute and Head of the “Millimeter and Submillimeter Astronomy” Research Dept.
    Max Planck Institute for Radio Astronomy, Bonn
    +49 228 525-471
    kmenten@mpifr-bonn.mpg.de

    Interstellar detection of iso-propanol in Sagittarius B2

    Many of us have probably already – literally – handled the chemical compound iso-propanol: it can used as an antiseptic, a solvent or a cleaning agent. But this substance is not only found on Earth: researchers led by Arnaud Belloche from the Max Planck Institute for Radio Astronomy in Bonn have now detected the molecule in interstellar space for the first time. It was observed in a “delivery room” of stars-the massive star-forming region Sagittarius B2 which is located near the centre of our Milky Way. The molecular cloud is the target of an extensive investigation of its chemical composition with the ALMA telescope in the Chilean Atacama Desert.

    1
    Alcohol in space: the position of star-forming molecular cloud Sagittarius B2 (Sgr B2) close to the central source of the Milky Way, Sgr A*. The image, taken from the GLOSTAR Galactic Plane Survey (Effelsberg & VLA) shows radio sources in the Galactic centre region. The isomers propanol and iso-propanol were both detected in Sgr B2 using the ALMA telescope.
    © GLOSTAR (Bruntaler et al. 2021, Astronomy & Astrophysics): Background image. Wikipedia (public domain): Propanol and isopropanol models.

    The search for molecules in space has been going on for more than 50 years. To date astronomers have identified 276 molecules in the interstellar medium. The “Cologne Database for Molecular Spectroscopy (CDMS)” provides spectroscopic data to detect these molecules contributed by many research groups and has been instrumental in their detection in many cases.

    The goal of the present work is to understand how organic molecules form in the interstellar medium, in particular in regions where new stars are born, and how complex these molecules can be. The underlying motivation is to establish connections to the chemical composition of bodies in the Solar system such as comets, as delivered for instance by the Rosetta mission to comet 67P/Churyumov–Gerasimenko a few years ago.

    An outstanding star forming region in our Galaxy where many molecules were detected in the past is Sagittarius B2 (Sgr B2), which is located close to the famous source Sgr A*, the supermassive black hole in the centre of our Galaxy.

    “Our group began to investigate the chemical composition of Sgr B2 more than 15 years ago with the IRAM 30-m telescope”, says Arnaud Belloche from the Max Planck Institute for Radio Astronomy (MPIfR) in Bonn/Germany, the leading author of the detection paper.

    “These observations were successful and led in particular to the first interstellar detection of several organic molecules, among many other results.”

    With the advent of the Atacama Large Millimeter/submillimeter Array (ALMA) ten years ago it became possible to go beyond what could be achieved toward Sgr B2 with a single-dish telescope and a long-term study of the chemical composition of Sgr B2 was started that took advantage of the high angular resolution and sensitivity provided by ALMA.

    So far, the ALMA observations have led to the identification of three new organic molecules (iso-propyl cyanide, N-methylformamide, urea) since 2014. The latest result within this ALMA project is now the detection of propanol (C3H7OH).

    Propanol is an alcohol, and is now the largest in this class of molecules that has been detected in interstellar space. This molecule exists in two forms (“isomers”), depending on which carbon atom the hydroxyl (OH) functional group is attached to: 1) normal-propanol, with OH bound to a terminal carbon atom of the chain, and 2) iso-propanol, with OH bound to the central carbon atom in the chain. Iso-propanol is also well known as the key ingredient in hand sanitizers on Earth. Both isomers of propanol in Sgr B2 were identified in the ALMA data set. It is the first time that iso-propanol is detected in the interstellar medium, and the first time that normal-propanol is detected in a star forming region. The first interstellar detection of normal-propanol was obtained shortly before the ALMA detection by a Spanish research team with single-dish radio telescopes in a molecular cloud not far from Sgr B2. The detection of iso-propanol toward Sgr B2, however, was only possible with ALMA.

    “The detection of both isomers of propanol is uniquely powerful in determining the formation mechanism of each. Because they resemble each other so much, they behave physically in very similar ways, meaning that the two molecules should be present in the same places at the same times”, says Rob Garrod from the University of Virginia. “The only open question is the exact amounts that are present – this makes their interstellar ratio far more precise than would be the case for other pairs of molecules. It also means that the chemical network can be tuned much more carefully to determine the mechanisms by which they form.”

    The ALMA telescope network was essential for the detection of both isomers of propanol toward Sgr B2, thanks to its high sensitivity, its high angular resolution, and its broad frequency coverage. One difficulty in the identification of organic molecules in the spectra of star forming regions is the spectral confusion. Each molecule emits radiation at specific frequencies-its spectral “fingerprint”-which is known from laboratory measurements.

    “The bigger the molecule the more spectral lines at different frequencies it produces. In a source like Sgr B2, there are so many molecules contributing to the observed radiation that their spectra overlap and it is difficult to disentangle their fingerprints and identify them individually”, says Holger Müller from Cologne University where laboratory work especially on normal-propanol was performed.

    Thanks to ALMA’s high angular resolution it was possible to isolate parts of Sgr B2 that emit very narrow spectral lines-five times more narrow than the lines detected on larger scales with the IRAM 30-m radio telescope! The narrowness of these lines reduces the spectral confusion, and this was key for the identification of both isomers of propanol in Sgr B2. The sensitivity of ALMA also played a key role: it would not have been possible to identify propanol in the collected data if the sensitivity had been just twice worse.

    This research is a long-standing effort to probe the chemical composition of sites in Sgr B2 where new stars are being formed, and thereby understand the chemical processes at work in the course of star formation. The goal is to determine the chemical composition of the star forming sites, and possibly identify new interstellar molecules. “Propanol has long been on our list of molecules to search for, but it is only thanks to the recent work done in our laboratory to characterize its rotational spectrum that we could identify its two isomers in a robust way”, says Oliver Zingsheim, also from Cologne University.

    Detecting closely related molecules that slightly differ in their structure (such as normal- and iso-propanol or, as was done in the past: normal- and iso-propyl cyanide) and measuring their abundance ratio allows the researchers to probe specific parts of the chemical reaction network that leads to their production in the interstellar medium.

    “There are still many unidentified spectral lines in the ALMA spectrum of Sgr B2 which means that still a lot of work is left to decipher its chemical composition. In the near future, the expansion of the ALMA instrumentation down to lower frequencies will likely help us to reduce the spectral confusion even further and possibly allow the identification of additional organic molecules in this spectacular source”, concludes Karl Menten, Director at the MPIfR and Head of its Millimeter and Submillimeter Astronomy research department.

    Science paper:
    Astronomy & Astrophysics

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    MPIFR campus

    Effelsberg Radio Telescope- a radio telescope in the Ahr Hills (part of the Eifel) in Bad Münstereifel(DE)

    The MPG Institute for Radio Astronomy [MPG Institut für Radioastronomie] (DE) is located in Bonn, Germany. It is one of 80 institutes in the MPG Society.

    By combining the already existing radio astronomy faculty of the University of Bonn led by Otto Hachenberg with the new MPG institute the MPG Institute for Radio Astronomy was formed. In 1972 the 100-m radio telescope in Effelsberg was opened. The institute building was enlarged in 1983 and 2002.

    The institute was founded in 1966 by the MPG Society as the “MPG Institut für Radioastronomie (MPIfR) (DE)”.

    The foundation of the institute was closely linked to plans in the German astronomical community to construct a competitive large radio telescope in (then) West Germany. In 1964, Professors Friedrich Becker, Wolfgang Priester and Otto Hachenberg of the Astronomische Institute der Universität Bonn submitted a proposal to the Stiftung Volkswagenwerk for the construction of a large fully steerable radio telescope.

    In the same year the Stiftung Volkswagenwerk approved the funding of the telescope project but with the condition that an organization should be found, which would guarantee the operations. It was clear that the operation of such a large instrument was well beyond the possibilities of a single university institute.

    Already in 1965 the MPG Society decided in principle to found the MPG Institut für Radioastronomie. Eventually, after a series of discussions, the institute was officially founded in 1966.

    MPG Society for the Advancement of Science [MPG Gesellschaft zur Förderung der Wissenschaften e. V.] is a formally independent non-governmental and non-profit association of German research institutes founded in 1911 as the Kaiser Wilhelm Society and renamed the Max Planck Society in 1948 in honor of its former president, theoretical physicist Max Planck. The society is funded by the federal and state governments of Germany as well as other sources.

    According to its primary goal, the MPG Society supports fundamental research in the natural, life and social sciences, the arts and humanities in its 83 (as of January 2014) MPG Institutes. The society has a total staff of approximately 17,000 permanent employees, including 5,470 scientists, plus around 4,600 non-tenured scientists and guests. Society budget for 2015 was about €1.7 billion.

    The MPG Institutes focus on excellence in research. The MPG Society has a world-leading reputation as a science and technology research organization, with 33 Nobel Prizes awarded to their scientists, and is generally regarded as the foremost basic research organization in Europe and the world. In 2013, the Nature Publishing Index placed the MPG institutes fifth worldwide in terms of research published in Nature journals (after Harvard University, The Massachusetts Institute of Technology, Stanford University and The National Institutes of Health). In terms of total research volume (unweighted by citations or impact), the Max Planck Society is only outranked by The Chinese Academy of Sciences [中国科学院](CN), The Russian Academy of Sciences [Росси́йская акаде́мия нау́к](RU) and Harvard University. The Thomson Reuters-Science Watch website placed the MPG Society as the second leading research organization worldwide following Harvard University, in terms of the impact of the produced research over science fields.

    The MPG Society and its predecessor Kaiser Wilhelm Society hosted several renowned scientists in their fields, including Otto Hahn, Werner Heisenberg, and Albert Einstein.

    History

    The organization was established in 1911 as the Kaiser Wilhelm Society, or Kaiser-Wilhelm-Gesellschaft (KWG), a non-governmental research organization named for the then German emperor. The KWG was one of the world’s leading research organizations; its board of directors included scientists like Walther Bothe, Peter Debye, Albert Einstein, and Fritz Haber. In 1946, Otto Hahn assumed the position of President of KWG, and in 1948, the society was renamed the Max Planck Society (MPG) after its former President (1930–37) Max Planck, who died in 1947.

    The MPG Society has a world-leading reputation as a science and technology research organization. In 2006, the Times Higher Education Supplement rankings of non-university research institutions (based on international peer review by academics) placed the MPG Society as No.1 in the world for science research, and No.3 in technology research (behind AT&T Corporation and The DOE’s Argonne National Laboratory.

    The domain mpg.de attracted at least 1.7 million visitors annually by 2008 according to a Compete.com study.

    MPG Institutes and research groups

    The MPG Society consists of over 80 research institutes. In addition, the society funds a number of Max Planck Research Groups (MPRG) and International Max Planck Research Schools (IMPRS). The purpose of establishing independent research groups at various universities is to strengthen the required networking between universities and institutes of the Max Planck Society.
    The research units are primarily located across Europe with a few in South Korea and the U.S. In 2007, the Society established its first non-European centre, with an institute on the Jupiter campus of Florida Atlantic University (US) focusing on neuroscience.
    The MPG Institutes operate independently from, though in close cooperation with, the universities, and focus on innovative research which does not fit into the university structure due to their interdisciplinary or transdisciplinary nature or which require resources that cannot be met by the state universities.

    Internally, MPG Institutes are organized into research departments headed by directors such that each MPI has several directors, a position roughly comparable to anything from full professor to department head at a university. Other core members include Junior and Senior Research Fellows.

    In addition, there are several associated institutes:
    International Max Planck Research Schools
    Together with the Association of Universities and other Education Institutions in Germany, the Max Planck Society established numerous International Max Planck Research Schools (IMPRS) to promote junior scientists:

    • Cologne Graduate School of Ageing Research, Cologne
    • International Max Planck Research School for Intelligent Systems, at the Max Planck Institute for Intelligent Systems located in Tübingen and Stuttgart
    • International Max Planck Research School on Adapting Behavior in a Fundamentally Uncertain World (Uncertainty School), at the Max Planck Institutes for Economics, for Human Development, and/or Research on Collective Goods
    • International Max Planck Research School for Analysis, Design and Optimization in Chemical and Biochemical Process Engineering, Magdeburg
    • International Max Planck Research School for Astronomy and Cosmic Physics, Heidelberg at the MPI for Astronomy
    • International Max Planck Research School for Astrophysics, Garching at the MPI for Astrophysics
    • International Max Planck Research School for Complex Surfaces in Material Sciences, Berlin
    • International Max Planck Research School for Computer Science, Saarbrücken
    • International Max Planck Research School for Earth System Modeling, Hamburg
    • International Max Planck Research School for Elementary Particle Physics, Munich, at the MPI for Physics
    • International Max Planck Research School for Environmental, Cellular and Molecular Microbiology, Marburg at the Max Planck Institute for Terrestrial Microbiology
    • International Max Planck Research School for Evolutionary Biology, Plön at the Max Planck Institute for Evolutionary Biology
    • International Max Planck Research School “From Molecules to Organisms”, Tübingen at the Max Planck Institute for Developmental Biology
    • International Max Planck Research School for Global Biogeochemical Cycles, Jena at the Max Planck Institute for Biogeochemistry
    • International Max Planck Research School on Gravitational Wave Astronomy, Hannover and Potsdam MPI for Gravitational Physics
    • International Max Planck Research School for Heart and Lung Research, Bad Nauheim at the Max Planck Institute for Heart and Lung Research
    • International Max Planck Research School for Infectious Diseases and Immunity, Berlin at the Max Planck Institute for Infection Biology
    • International Max Planck Research School for Language Sciences, Nijmegen
    • International Max Planck Research School for Neurosciences, Göttingen
    • International Max Planck Research School for Cognitive and Systems Neuroscience, Tübingen
    • International Max Planck Research School for Marine Microbiology (MarMic), joint program of the Max Planck Institute for Marine Microbiology in Bremen, the University of Bremen, the Alfred Wegener Institute for Polar and Marine Research in Bremerhaven, and the Jacobs University Bremen
    • International Max Planck Research School for Maritime Affairs, Hamburg
    • International Max Planck Research School for Molecular and Cellular Biology, Freiburg
    • International Max Planck Research School for Molecular and Cellular Life Sciences, Munich
    • International Max Planck Research School for Molecular Biology, Göttingen
    • International Max Planck Research School for Molecular Cell Biology and Bioengineering, Dresden
    • International Max Planck Research School Molecular Biomedicine, program combined with the ‘Graduate Programm Cell Dynamics And Disease’ at the University of Münster and the Max Planck Institute for Molecular Biomedicine
    • International Max Planck Research School on Multiscale Bio-Systems, Potsdam
    • International Max Planck Research School for Organismal Biology, at the University of Konstanz and the Max Planck Institute for Ornithology
    • International Max Planck Research School on Reactive Structure Analysis for Chemical Reactions (IMPRS RECHARGE), Mülheim an der Ruhr, at the Max Planck Institute for Chemical Energy Conversion
    • International Max Planck Research School for Science and Technology of Nano-Systems, Halle at Max Planck Institute of Microstructure Physics
    • International Max Planck Research School for Solar System Science at the University of Göttingen hosted by MPI for Solar System Research
    • International Max Planck Research School for Astronomy and Astrophysics, Bonn, at the MPI for Radio Astronomy (formerly the International Max Planck Research School for Radio and Infrared Astronomy)
    • International Max Planck Research School for the Social and Political Constitution of the Economy, Cologne
    • International Max Planck Research School for Surface and Interface Engineering in Advanced Materials, Düsseldorf at Max Planck Institute for Iron Research GmbH
    • International Max Planck Research School for Ultrafast Imaging and Structural Dynamics, Hamburg

    Max Planck Schools

    • Max Planck School of Cognition
    • Max Planck School Matter to Life
    • Max Planck School of Photonics

    Max Planck Center

    • The Max Planck Centre for Attosecond Science (MPC-AS), POSTECH Pohang
    • The Max Planck POSTECH Center for Complex Phase Materials, POSTECH Pohang

    Max Planck Institutes

    Among others:
    • Max Planck Institute for Neurobiology of Behavior – caesar, Bonn
    • Max Planck Institute for Aeronomics in Katlenburg-Lindau was renamed to Max Planck Institute for Solar System Research in 2004;
    • Max Planck Institute for Biology in Tübingen was closed in 2005;
    • Max Planck Institute for Cell Biology in Ladenburg b. Heidelberg was closed in 2003;
    • Max Planck Institute for Economics in Jena was renamed to the Max Planck Institute for the Science of Human History in 2014;
    • Max Planck Institute for Ionospheric Research in Katlenburg-Lindau was renamed to Max Planck Institute for Aeronomics in 1958;
    • Max Planck Institute for Metals Research, Stuttgart
    • Max Planck Institute of Oceanic Biology in Wilhelmshaven was renamed to Max Planck Institute of Cell Biology in 1968 and moved to Ladenburg 1977;
    • Max Planck Institute for Psychological Research in Munich merged into the Max Planck Institute for Human Cognitive and Brain Sciences in 2004;
    • Max Planck Institute for Protein and Leather Research in Regensburg moved to Munich 1957 and was united with the Max Planck Institute for Biochemistry in 1977;
    • Max Planck Institute for Virus Research in Tübingen was renamed as Max Planck Institute for Developmental Biology in 1985;
    • Max Planck Institute for the Study of the Scientific-Technical World in Starnberg (from 1970 until 1981 (closed)) directed by Carl Friedrich von Weizsäcker and Jürgen Habermas.
    • Max Planck Institute for Behavioral Physiology
    • Max Planck Institute of Experimental Endocrinology
    • Max Planck Institute for Foreign and International Social Law
    • Max Planck Institute for Physics and Astrophysics
    • Max Planck Research Unit for Enzymology of Protein Folding
    • Max Planck Institute for Biology of Ageing

     
  • richardmitnick 1:31 pm on June 24, 2022 Permalink | Reply
    Tags: "Another few weeks of observations could tell us if the Wow! signal repeats", , , Radio Astronomy, The Ohio University   

    From The Ohio University via “phys.org” : “Another few weeks of observations could tell us if the Wow! signal repeats” 

    Ohio U bloc

    From The Ohio University

    via

    “phys.org”

    June 23, 2022
    Brian Koberlein

    1
    An aerial view of the Big Ear telescope. Credit: Bigear.org / NAAPO.

    In the decades-long search for extraterrestrial intelligence, there has never been confirmed evidence of an alien signal. There have, however, been a few tantalizing mysteries. Perhaps the greatest of these is known as the Wow! signal.

    Observed on 15 August 1977 by the Big Ear radio telescope at The Ohio University, the signal was a strong, continuous, narrow band radio signal lasting at least 72 seconds. Our knowledge of the signal is limited given the design of Big Ear. Rather than being able to track radio signals like most modern radio telescopes, Big Ear was set to a particular elevation and relied on Earth’s rotation to scan across the sky. The reason the Wow! signal lasts 72 seconds is that’s how long it took the source to sweep across Big Ear’s observation range.

    Big Ear was also a passive telescope. Astronomers simply set it up, and it would run on its own, recording the strength of signals as it goes. Because of this, the signal was only discovered days after the event when recorded observations were reviewed. By the time astronomers could go back to observe the source, the event was long over.

    But despite having just one observation, the Wow! signal is considered the strongest candidate for an extraterrestrial signal. Several natural origins have been proposed, but all of them are a bit lacking. The most basic idea is that the signal was of terrestrial origin, perhaps a plane passing overhead, or a radio signal scattered off space debris. But a plane wouldn’t be in range for more than 72 seconds, and there is no record of such a flight. A scattered signal is possible, but the strength of the signal would be unusual, and the frequency of the Wow! signal is within a range where transmissions are restricted.

    2
    Plot of signal strength vs time of the Wow! signal on August 15, 1977. Credit: Maksim Rossomakhin.

    Several years ago it was proposed that the signal might have been caused by comets that were near the observed area of the sky, but this has since been disproven. While two comets were close to the source location, they weren’t really within the observed range. And comets aren’t likely to emit such a strong narrowband signal.

    One interesting aspect of the signal is that its frequency was very close to that of the so-called 21-centimeter line. This is a faint radio emission caused by neutral hydrogen in the universe. Because hydrogen is the most common element in the cosmos, any radio astronomers in the universe would make observations at that frequency. If you wanted to get the attention of alien astronomers, a strong signal near that frequency would be a good way to do it.

    Given the tantalizing nature of the Wow! signal, there have been several attempts at repeat observations. Several radio telescopes have been aimed at the source over the years, but to no luck. Every observation in that area since has turned up nothing. So what’s an astronomer to do? Well, one way to tackle the problem is to look at what your observations exclude. That’s the idea behind a recent paper for MNRAS.

    3
    Applying Bayesian statistics to a likely outcome. Credit: Wikipedia.

    In this work, the authors argue that the source could be some kind of stochastic repeater. Most repeating sources are periodic. Things like variable stars or fast radio bursts can have a predictable variability. Astronomers have considered this idea, and have made observations that rule out a source with a regular periodicity. A stochastic repeater is a bit different. Rather than having a measurable period, stochastic repeaters repeat somewhat randomly. A good example would be earthquakes. We know where they generally happen, know they will happen again, but predicting exactly when is nigh on impossible. Astrophysical processes can be stochastic in a similar way.

    On the face of it, this seems like a silly idea. We’ve never seen the Wow! signal repeat, and we’ve proved it can’t be repeating periodically, but maybe it’s been repeating non-randomly such that we’ve never observed it. It sounds like the authors are arguing that it must be a non-random repeater because we’ve never observed it repeat. But the idea isn’t as silly as it sounds. The authors look at when an unobserved burst might have occurred, and apply Bayesian statistics to calculate when a future burst might occur.

    Bayesian statistics is subtle but powerful. It’s more than just calculating the odds of a likely event. It looks at the pattern of events to predict specific outcomes. It takes into account not just how often something has occurred, but how those events changed over time. So, knowing of one burst event, and knowing when other burst events haven’t occurred, the authors calculate the times at which future events are most likely. This is good to know since we can now specifically observe the regions during the most likely event periods. If the Wow! signal was a stochastic repeater, then we’ll likely catch a new event. If we don’t see another event, we can rule out stochastic repeaters as a likely cause.

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition

    Ohio U campus

    In 1786, 11 men gathered at the Bunch of Grapes Tavern in Boston to propose development of the area north of the Ohio River and west of the Allegheny Mountains known then as the Ohio Country. Led by Manasseh Cutler and Rufus Putnam, the Ohio Company petitioned Congress to take action on the proposed settlement. The eventual outcome was the enactment of the Northwest Ordinance of 1787, which provided for settlement and government of the territory and stated that “…schools and the means of education shall forever be encouraged.”

    In 1803, Ohio became a state and on February 18, 1804, the Ohio General Assembly passed an act establishing “The Ohio University.” The University opened in 1808 with one building, three students, and one professor, Jacob Lindley. One of the first two graduates of the University, Thomas Ewing, later became a United States senator and distinguished himself as cabinet member or advisor to four presidents.

    Twenty-four years after its founding, in 1828, Ohio University conferred an A.B. degree on John Newton Templeton, its first black graduate and only the third black man to graduate from a college in the United States. In 1873, Margaret Boyd received her B.A. degree and became the first woman to graduate from the University. Soon after, the institution graduated its first international alumnus, Saki Taro Murayama of Japan, in 1895.

     
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