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  • richardmitnick 2:28 pm on December 4, 2016 Permalink | Reply
    Tags: Astronomy, , Cold brown dwarfs, ,   

    From Science: “Alien life could thrive in the clouds of failed stars” 

    ScienceMag
    Science Magazine

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    The comfortably warm atmosphere of a brown dwarf is an underappreciated potential home for alien life, scientists say. Mark Garlick/Science Source

    Dec. 2, 2016
    Joshua Sokol

    There’s an abundant new swath of cosmic real estate that life could call home—and the views would be spectacular. Floating out by themselves in the Milky Way galaxy are perhaps a billion cold brown dwarfs, objects many times as massive as Jupiter but not big enough to ignite as a star. According to a new study, layers of their upper atmospheres sit at temperatures and pressures resembling those on Earth, and could host microbes that surf on thermal updrafts.

    The idea expands the concept of a habitable zone to include a vast population of worlds that had previously gone unconsidered. “You don’t necessarily need to have a terrestrial planet with a surface,” says Jack Yates, a planetary scientist at the University of Edinburgh in the United Kingdom, who led the study.

    Atmospheric life isn’t just for the birds. For decades, biologists have known about microbes that drift in the winds high above Earth’s surface. And in 1976, Carl Sagan envisioned the kind of ecosystem that could evolve in the upper layers of Jupiter, fueled by sunlight. You could have sky plankton: small organisms he called “sinkers.” Other organisms could be balloonlike “floaters,” which would rise and fall in the atmosphere by manipulating their body pressure. In the years since, astronomers have also considered the prospects of microbes in the carbon dioxide atmosphere above Venus’s inhospitable surface.

    Yates and his colleagues applied the same thinking to a kind of world Sagan didn’t know about. Discovered in 2011, some cold brown dwarfs have surfaces roughly at room temperature or below; lower layers would be downright comfortable. In March 2013, astronomers discovered WISE 0855-0714, a brown dwarf only 7 light-years away that seems to have water clouds in its atmosphere. Yates and his colleagues set out to update Sagan’s calculations and to identify the sizes, densities, and life strategies of microbes that could manage to stay aloft in the habitable region of an enormous atmosphere of predominantly hydrogen gas. Sink too low and you are cooked or crushed. Rise too high and you might freeze.

    On such a world, small sinkers like the microbes in Earth’s atmosphere or even smaller would have a better chance than Sagan’s floaters, the researchers will report in an upcoming issue of The Astrophysical Journal. But a lot depends on the weather: If upwelling winds are powerful on free-floating brown dwarfs, as seems to be true in the bands of gas giants like Jupiter and Saturn, heavier creatures can carve out a niche. In the absence of sunlight, they could feed on chemical nutrients. Observations of cold brown dwarf atmospheres reveal most of the ingredients Earth life depends on: carbon, hydrogen, nitrogen, and oxygen, though perhaps not phosphorous.

    The idea is speculative but worth considering, says Duncan Forgan, an astrobiologist at the University of St. Andrews in the United Kingdom, who did not participate in the study but says he is close to the team. “It really opens up the field in terms of the number of objects that we might then think, well, these are habitable regions.”

    So far, only a few dozen cold brown dwarfs have been discovered, though statistics suggest there should be about 10 within 30 light-years of Earth. These should be ripe targets for the James Webb Space Telescope (JWST), which is sensitive in the infrared where brown dwarfs shine brightest.

    NASA/ESA/CSA Webb Telescope annotated
    NASA/ESA/CSA Webb Telescope annotated

    After it launches in 2018, the JWST should reveal the weather and the composition of their atmospheres, says Jackie Faherty, an astronomer at the Carnegie Institution for Science in Washington, D.C. “We’re going to start getting gorgeous spectra of these objects,” she says. “This is making me think about it.”

    Testing for life would require anticipating a strong spectral signature of microbe byproducts like methane or oxygen, and then differentiating it from other processes, Faherty says. Another issue would be explaining how life could arise in an environment that lacks the water-rock interfaces, like hydrothermal vents, where life is thought to have begun on Earth. Perhaps life could develop through chemical reactions on the surfaces of dust grains in the brown dwarf’s atmosphere, or perhaps it gained a foothold after arriving as a hitchhiker on an asteroid. “Having little microbes that float in and out of a brown dwarf atmosphere is great,” Forgan says. “But you’ve got to get them there first.”

    See the full article here .

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  • richardmitnick 10:56 am on December 4, 2016 Permalink | Reply
    Tags: Astronomy, , ,   

    From ESA: “First views of Mars show potential for ESA’s new orbiter” 

    ESA Space For Europe Banner

    European Space Agency

    29 November 2016
    Håkan Svedhem
    ESA ExoMars TGO Project Scientist
    Email: hakan.svedhem@esa.int

    Markus Bauer
    ESA Science and Robotic Exploration Communication Officer
    Tel: +31 71 565 6799
    Mob: +31 61 594 3 954
    Email: markus.bauer@esa.int

    ESA’s new ExoMars orbiter has tested its suite of instruments in orbit for the first time, hinting at a great potential for future observations.


    Access mp4 video here .

    ESA/ExoMars
    ESA/ExoMars

    The Trace Gas Orbiter, or TGO, a joint endeavour between ESA and Roscosmos, arrived at Mars on 19 October. Its elliptical orbit takes it from 230–310 km above the surface to around 98 000 km every 4.2 days.

    ESA/ExoMars Trace Gas Orbiter
    ESA/ExoMars Trace Gas Orbiter

    It spent the last two orbits during 20–28 November testing its four science instruments for the first time since arrival, and making important calibration measurements.

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    First look at the atmosphere. Credit: ESA/Roscosmos/ExoMars/NOMAD/BISA/IAA/INAF/OU

    Data from the first orbit has been made available for this release to illustrate the range of observations to be expected once the craft arrives into its near-circular 400 km-altitude orbit late next year.

    TGO’s main goal is to make a detailed inventory of rare gases that make up less than 1% of the atmosphere’s volume, including methane, water vapour, nitrogen dioxide and acetylene.

    Of high interest is methane, which on Earth is produced primarily by biological activity, and to a smaller extent by geological processes such as some hydrothermal reactions.

    The two instruments tasked with this role have now demonstrated they can take highly sensitive spectra of the atmosphere. During the test observations last week, the Atmospheric Chemistry Suite focused on carbon dioxide, which makes up a large volume of the planet’s atmosphere, while the Nadir and Occultation for Mars Discovery instrument homed in on water.

    They also coordinated observations with ESA’s Mars Express and NASA’s Mars Reconnaissance Orbiter, as they will in the future.

    ESA/Mars Express Orbiter
    ESA/Mars Express Orbiter

    NASA/Mars Reconnaissance Orbiter
    NASA/Mars Reconnaissance Orbiter

    Complementary measurements by the orbiter’s neutron detector, FREND, will measure the flow of neutrons from the planet’s surface. Created by the impact of cosmic rays, the way in which they are emitted and their speed on arriving at TGO points to the composition of the surface layer, in particular to water or ice just below the surface.

    The instrument has been active at various times during the cruise to Mars and on recent occasions while flying close to the surface could identify the relative difference between regions of known higher and lower neutron flux, although it will take several months to produce statistically significant results.

    Similarly, the instrument showed a clear increase in neutron detections when close to Mars compared to when it was further away.

    The different capabilities of the Colour and Stereo Surface Imaging System were also demonstrated, with 11 images captured during the first close flyby on 22 November.

    At closest approach the spacecraft was 235 km from the surface, and flying over the Hebes Chasma region, just north of the Valles Marineris canyon system. These are some of the closest images that will ever be taken of the planet by TGO, given that the spacecraft’s final orbit will be at around 400 km altitude.

    The camera team also completed a quick first test of producing a 3D reconstruction of a region in Noctis Labyrinthus, from a stereo pair of images.

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    First ExoMars stereo reconstruction. Credit: ESA/Roscosmos/ExoMars/CaSSIS/UniBE

    Although the images are impressively sharp, data collected during this test period will help to improve the camera’s onboard software as well as the quality of the images after processing.

    “We are extremely happy and proud to see that all the instruments are working so well in the Mars environment, and this first impression gives a fantastic preview of what’s to come when we start collecting data for real at the end of next year,” says Håkan Svedhem, ESA’s TGO Project Scientist.

    “Not only is the spacecraft itself clearly performing well, but I am delighted to see the various teams working together so effectively in order to give us this impressive insight.

    “We have identified areas that can be fine-tuned well in advance of the main science mission, and we look forward to seeing what this amazing science orbiter will do in the future.”

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    ExoMars science orbit 1. Credit: ESA

    See the full article here .

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    The European Space Agency (ESA), established in 1975, is an intergovernmental organization dedicated to the exploration of space, currently with 19 member states. Headquartered in Paris, ESA has a staff of more than 2,000. ESA’s space flight program includes human spaceflight, mainly through the participation in the International Space Station program, the launch and operations of unmanned exploration missions to other planets and the Moon, Earth observation, science, telecommunication as well as maintaining a major spaceport, the Guiana Space Centre at Kourou, French Guiana, and designing launch vehicles. ESA science missions are based at ESTEC in Noordwijk, Netherlands, Earth Observation missions at ESRIN in Frascati, Italy, ESA Mission Control (ESOC) is in Darmstadt, Germany, the European Astronaut Centre (EAC) that trains astronauts for future missions is situated in Cologne, Germany, and the European Space Astronomy Centre is located in Villanueva de la Cañada, Spain.

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  • richardmitnick 7:15 am on December 4, 2016 Permalink | Reply
    Tags: Astronomy, , , , , Why must time be a dimension?   

    From Starts With a Bang: “Why must time be a dimension?” 

    From Ethan Siegel
    12.3.16

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    A time-lapse photo like this composition reminds us that photographs are normally snapshots of locations at particular moments, with each moment distinct and unique from the last. Image credit: flickr user Anthony Pucci.

    Sure, we move through it just like space, but it was the aftermath of Einstein that led to us truly understanding it.

    “It is old age, rather than death, that is to be contrasted with life. Old age is life’s parody, whereas death transforms life into a destiny: in a way it preserves it by giving it the absolute dimension. Death does away with time.” -Simone de Beauvoir

    When we think about how we can move through the Universe, we immediately think of three different directions. Left-or-right, forwards-or-backwards, and upwards-or-downwards: the three independent directions of a Cartesian grid. All three of those count as dimensions, and specifically, as spatial dimensions. But we commonly talk about a fourth dimension of a very different type: time. But what makes time a dimension at all? That’s this week’s Ask Ethan question from Thomas Anderson, who wants to know:

    “I have always been a little perplexed about the continuum of 3+1 dimensional Space-time. Why is it always 3 [spatial] dimensions plus Time?”

    Let’s start by looking at the three dimensions of space you’re familiar with.

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    On the surface of a world like the Earth, two coordinates, like latitude and longitude, are sufficient to define a location. Image credit: Wikimedia Commons user Hellerick.

    Here on the surface of the Earth, we normally only need two coordinates to pinpoint our location: latitude and longitude, or where you are along the north-south and east-west axes of Earth. If you’re willing to go underground or above the Earth’s surface, you need a third coordinate — altitude/depth, or where you are along the up-down axis — to describe your location. After all, someone at your exact two-dimensional, latitude-and-longitude location but in a tunnel beneath your feet or in a helicopter overhead isn’t truly at the same location as you. It takes three independent pieces of information to describe your location in space.

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    Your location in this Universe isn’t just described by spatial coordinates (where), but also by a time coordinate (when). Image credit: Pixabay user rmathews100.

    But spacetime is even more complicated than space, and it’s easy to see why. The chair you’re sitting in right now can have its location described by those three coordinates: x, y and z. But it’s also occupied by you right now, as opposed to an hour ago, yesterday or ten years from now. In order to describe an event, knowing where it occurs isn’t enough; you also need to know when, which means you need to know the time coordinate, t. This played a big deal for the first time in relativity, when we were thinking about the issue of simultaneity. Start by thinking of two separate locations connected by a path, with two people walking from each location to the other one.

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    Two points connected by a 1-dimensional (linear) path. Image credit: Wikimedia Commons user Simeon87.

    You can visualize their paths by putting two fingers, one from each hand, at the two starting locations and “walking” them towards their destinations. At some point, they’re going to need to pass by one another, meaning your two fingers are going to have to be in the same spot at the same time. In relativity, this is what’s known as a simultaneous event, and it can only occur when all the space components and all the time components of two different physical objects align.

    This is supremely non-controversial, and explains why time needs to be considered as a dimension that we “move” through, the same as any of the spatial dimensions. But it was Einstein’s special theory of relativity that led his former professor, Hermann Minkowski, to devise a formulation that put the three space dimensions and the one time dimension together.

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    NASA

    We all realize that to move through space requires motion through time; if you’re here, now, you cannot be somewhere else now as well, you can only get there later. In 1905, Einstein’s special relativity taught us that the speed of light is a universal speed limit, and that as you approach it you experience the strange phenomena of time dilation and length contraction. But perhaps the biggest breakthrough came in 1907, when Minkowski realized that Einstein’s relativity had an extraordinary implication: mathematically, time behaves exactly the same as space does, except with a factor of c, the speed of light in vacuum, and a factor of i, the imaginary number √(-1).

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    An example of a light cone, the three-dimensional surface of all possible light rays arriving at and departing from a point in spacetime. Image credit: Wikimedia Commons user MissMJ.

    Putting all of these revelations together yielded a new picture of the Universe, particularly as respects how we move through it.

    If you’re completely stationary, remaining in the same spatial location, you move through time at its maximal rate.
    The faster you move through space, the slower you move through time, and the shorter the spatial distances in your direction-of-motion appear to be.
    And if you were completely massless, you would move at the speed of light, where you would traverse your direction-of-motion instantaneously, and no time would pass for you.

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    A stationary observer sees time pass normally, but an observer moving rapidly through space will have their clock run slower relative to the stationary observer. Image credit: Michael Schmid of Wikimedia Commons.

    From a physics point of view, the implications are astounding. It means that all massless particles are intrinsically stable, since no time can ever pass for them. It means that an unstable particle, like a muon created in the upper atmosphere, can reach the Earth’s surface, despite the fact that multiplying its lifetime (2.2 µs) by the speed of light yields a distance (660 meters) that’s far less than the distance it must travel. And it means that if you had a pair of identical twins and you left one on Earth while the other took a relativistic journey into space, the journeying twin would be much younger upon return, having experienced the passage of less time.

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    Mark and Scott Kelly at the Johnson Space Center, Houston Texas; one spent a year in space (and aged slightly less) while the other remained on the ground. Image credit: NASA.

    As Minkowski said in 1908,

    “The views of space and time which I wish to lay before you have sprung from the soil of experimental physics, and therein lies their strength. They are radical. Henceforth, space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality.”

    Today, the formulation of spacetime is even more generic, and encompasses the curvature inherent to space itself, which is how special relativity got generalized. But the reason time is just as good a dimension as space is because we’re always moving through it, and the reason it’s sometimes written as a “1″ in “3+1″ (instead of just treated as another “1″ of the “4″) is because increasing your motion through space decreases your motion through time, and vice versa. (Mathematically, this is where the i comes in.)


    Having your camera anticipate the motion of objects through time is just one practical application of the idea of time-as-a-dimension.

    The remarkable thing is that anyone, regardless of their motion through space relative to anyone else, will see these same rules, these same effects and these same consequences. If time weren’t a dimension in this exact way, the laws of relativity would be invalid, and there might yet be a valid concept such as absolute space. We need the dimensionality of time for physics to work the way it does, and yet our Universe provides for it oh so well. Be proud to give it a “+1” in all you do.

    See the full article here .

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    Stem Education Coalition

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

     
  • richardmitnick 10:56 pm on December 3, 2016 Permalink | Reply
    Tags: Astronomy, , GREGOR solar telescope, Kiepenheuer Institute for Solar Physics   

    From Kiepenheuer Institute for Solar Physics: “New Solar Telescope GREGOR” 

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    Kiepenheuer Institute for Solar Physics

    KIP telescope GREGOR

    First Results from the GREGOR Solar Telescope

    2

    GREGOR is Europe’s largest solar telescope and is a part of the Teide Observatory on Tenerife, on the Canary Islands, Spain. It observes the Sun at visible and near-infrared wavelengths to collect data from the photosphere and the overlying chromosphere. GREGOR measures magnetic field and material motion with high precision and with a spatial resolution of some 50 km on the solar surface.

    The development of GREGOR started around the turn of the millennium and marked an important paradigm change. Since the 1970s, large solar telescopes were constructed as evacuated systems in order to eliminate internal seeing and to improve the imaging quality. With an aperture of 1.5 meters, an evacuated telescope with an entrance window was no longer an option, so GREGOR is an open telescope with active cooling of the primary mirror. A retractable dome allows flushing of the telescope with ambient air. Thanks to its mature adaptive optics and a suite of spectroscopic, polarimetric, and imaging instruments, it is now one of world’s most powerful solar telescopes.

    See the full article here .

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    KIS operates the german solar telescopes at Teide Observatory on Tenerife (Spain)

    The Kiepenheuer Institute for Solar Physics (KIS) conducts experimental and theoretical investigations of physical processes on and within the Sun. Its headquarter is in Freiburg, Germany. The KIS operates the german solar telescopes at Teide Observatory on Tenerife (Spain) where most of the scientific observations are performed. KIS offers lectures on astronomy and astrophysics at Freiburg university and trains young scientists.

     
  • richardmitnick 7:45 am on December 3, 2016 Permalink | Reply
    Tags: , Astronomy, , Classifying Supernovae,   

    From astrobites: “Classifying Supernovae” 

    Astrobites bloc

    Astrobites

    Dec 2, 2016
    Ashley Villar

    Supernovae (SNe) are the deaths of stars big and small. Like many older fields of astronomy, the study of supernovae is plagued with dated nomenclature which is largely unrelated to the physics driving these dazzling events. Below is an enumeration of many known supernova subtypes and simple guidelines for classification. These classifications will rely on your knowledge of spectra, so we recommend reading our spectroscopy guide first!

    Thermonuclear Explosions:

    Type Ia: Type Ia supernovae are the most famous type for two reasons: we find them most often, and they can be used to study cosmology. The latter is true due to their striking lack of diversity. The shape of their light curves (the luminosity of the supernovae as a function of time) can be used to measure their maximum luminosity. This means that Type Ia SNe can be used as standard candles to measure distances. Ironically, the origin of these explosions is still uncertain. Type Ia supernovae are likely caused by the thermonuclear explosions of white dwarf stars; however,it’s currently unclear if these explosions are from single white dwarfs or merging white dwarf binaries. In our simple classification, Type Ia supernovae lack hydrogen and have a strong silicon absorption line near its maximum luminosity.

    Core-collapse Explosions:

    Type Ib: Type Ib supernovae are formed when a massive star collapses under its own gravity. This star must have its outer envelope of hydrogen stripped away, because we observe no hydrogen in these spectra of these objects. However, we do observe the second ‘onion layer’ of helium.

    Type Ic: Type Ic supernovae are also formed when a massive star collapses under its own gravity. The stars that produce these supernovae have both their hydrogen and helium layers stripped away over the course of their lives. Because of this, we do not see hydrogen or helium in the spectra of Type Ic SNe.

    Type Ic – Broad Lined (Type Ic – BL): Some Type Ic supernovae have very broad lines (a speed of 20,000 km/s for the bulk of the material!) compared to normal Type Ic SNe. As you might expect, these supernovae typically have higher kinetic energies than normal Ic SNe as well. The origin of the increased energy is unclear and a highly debated topic.

    GRB-SNe: Some Type Ic – BL supernovae are associated with another transient phenomenon: gamma-ray bursts. These events have been interpreted as the collapse of a massive star with the formation of a jet pointed in our direction. It’s possible that all Type Ic – BL SNe are associated with GRBs and some are just not pointed towards us, but we’re not sure yet!

    Superluminous Supernovae (Type I/II SLSNe): A subset of all supernovae are found to be 100 times or brighter than most supernovae. This class is therefore called “superluminous supernovae” — clever, right? SLSNe are, like normal SNe, divided into Type I (lacking hydrogen) and Type II (showing hydrogen). Type II SLSNe are typically spectroscopically similar to Type IIn SNe (see below), so they might be extreme versions of the same explosions. However, the mechanics behind Type I SLSNe is highly debated.

    Type IIn: Type IIn supernovae have very narrow (or slow) hydrogen lines in their spectra, superimposed on the typical broad lines. These narrow lines are interpreted as hydrogen which was blown off of the star before it exploded. To support this argument, a few of these Type IIn supernovae, like SN 2009ip, have had extreme outbursts before their final explosion.

    Type IIP/II L: Type IIP/IIL contain relatively broad hydrogen lines. These explosions are thought to be the deaths of red supergiant stars, which are enshrined by their hydrogen envelopes. The light curves of Type IIP and Type IIL supernovae have distinctive shapes, with a long plateau lasting for hundreds of days.

    Type IIb: Type IIb supernovae largely break our classification system, but we have included them to give you a glimpse of how funky this business is. Spectra of Type IIb SNe begin with strong hydrogen lines, putting them in the Type II category. However, at late times they lose this hydrogen emission and instead resemble Type Ib SNe (with helium features). These explosions are likely from stars which have lost part of their hydrogen envelopes.

    Below is a visual guide to classifying supernovae. To be clear: the real classifications of supernovae are a challenging business, and require a complex ruleset. This is especially true as the subclasses become more specialized. In the below image, for example, it is entirely possible for a SLSN to be associated with a long GRB, or a Type Ia to be cloaked in hydrogen.

    1

    See the full article here .

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    What do we do?

    Astrobites is a daily astrophysical literature journal written by graduate students in astronomy. Our goal is to present one interesting paper per day in a brief format that is accessible to undergraduate students in the physical sciences who are interested in active research.
    Why read Astrobites?

    Reading a technical paper from an unfamiliar subfield is intimidating. It may not be obvious how the techniques used by the researchers really work or what role the new research plays in answering the bigger questions motivating that field, not to mention the obscure jargon! For most people, it takes years for scientific papers to become meaningful.
    Our goal is to solve this problem, one paper at a time. In 5 minutes a day reading Astrobites, you should not only learn about one interesting piece of current work, but also get a peek at the broader picture of research in a new area of astronomy.

     
  • richardmitnick 2:38 pm on December 2, 2016 Permalink | Reply
    Tags: , Astronomy, , , , Einstein@Home Finds a Double Neutron Star   

    From AAS NOVA: ” Einstein@Home Finds a Double Neutron Star” 

    AASNOVA

    American Astronomical Society

    2 December 2016
    Susanna Kohler

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    Artist’s impression of a double-pulsar system. A new double-neutron-star system was recently discovered using Einstein@Home, a program that analyzes data on home computers. [John Rowe Animations]

    Have you been contributing your computer idle time to the Einstein@Home project? If so, you’re partly responsible for the program’s recent discovery of a new double-neutron-star system that will be key to learning about general relativity and stellar evolution.

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    The 305-m Arecibo Radio Telescope, built into the landscape at Arecibo, Puerto Rico. [NOAO/AURA/NSF/H. Schweiker/WIYN]

    The Hunt for Pulsars

    Observing binary systems containing two neutron stars — and in particular, measuring the timing of the pulses when one or both companions is a pulsar — can provide highly useful tests of general relativity and binary stellar evolution. Unfortunately, these systems are quite rare: of ~2500 known radio pulsars, only 14 of them are in double-neutron-star binaries.

    To find more systems like these, we perform large-scale, untargeted radio-pulsar surveys — like the ongoing Pulsar-ALFA survey conducted with the enormous 305-m radio telescope at Arecibo Observatory in Puerto Rico. But combing through these data for the signature of a highly accelerated pulsar (the acceleration is a clue that it’s in a compact binary) is very computationally expensive.

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    PSR J1913+1102’s L-band pulse profile, created by phase-aligning and summing all observations. [Adapted from Lazarus et al. 2016]

    To combat this problem, the Einstein@Home project was developed.

    Einstein@home

    Einstein@home

    My BOINC results:
    boincstatsimage-new

    See the full article here.

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    Einstein@Home is a World Year of Physics 2005 and an International Year of Astronomy 2009 project supported by the American Physical Society (APS) and by a number of international organizations.

    Einstein@Home uses your computer’s idle time to search for weak astrophysical signals from spinning neutron stars (also called pulsars) using data from the LIGO gravitational-wave detectors, the Arecibo radio telescope, and the Fermi gamma-ray satellite. Einstein@Home volunteers have already discovered more than three dozens new neutron stars, and we hope to find many more in the future. Our long-term goal is to make the first direct detections of gravitational-wave emission from spinning neutron stars. Gravitational waves were predicted by Albert Einstein almost a century ago, but have never been directly detected. Such observations would open up a new window on the universe, and usher in a new era in astronomy.

    To join this project go to BOINC, download the software and attach to the project. While you are at BOINC, review all of the projects and see what else might be of interest.

    boinclarge

    boinc-wallpaper

    Einstein@Home allows anyone to volunteer their personal computer’s idle time to help run the analysis of survey data in the search for pulsars. In a recent publication led by Patrick Lazarus (Max Planck Institute for Radio Astronomy), the Einstein@Home team announced the discovery of the pulsar PSR J1913+1102 — a member of what seems to be a brand new double-neutron-star system.

    See the full article here .

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  • richardmitnick 2:08 pm on December 2, 2016 Permalink | Reply
    Tags: Astronomy, , , ,   

    From Symmetry: “Viewing our turbulent universe” 

    Symmetry Mag
    Symmetry

    12/02/16
    Liz Kruesi

    Construction has begun for the Cherenkov Telescope Array [CTA], a discovery machine that will study the highest energy objects and events across the entire sky.

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    Daniel Mazinkn, CTA Observatory

    Billions of light-years away, a supermassive black hole is spewing high-energy radiation, launching it far outside of the confines of its galaxy. Some of the gamma rays released by that turbulent neighborhood travel unimpeded across the universe, untouched by the magnetic fields threading the cosmos, toward our small, rocky, blue planet.

    We have space-based devices, such as the Fermi Gamma-ray Space Telescope, that can detect those messengers, allowing us to see into the black hole’s extreme environment or search for evidence of dark matter.

    NASA/Fermi Telescope
    NASA/Fermi Telescope

    But Earth’s atmosphere blocks gamma rays. When they meet the atmosphere, sequences of interactions with gas molecules break them into a shower of fast-moving secondary particles. Some of those generated particles—which could be, for example, fast-moving electrons and their antiparticles, positrons—speed through the atmosphere so quickly that they generate a faint flash of blue light, called Cherenkov radiation.

    A special type of telescope—large mirrors fitted with small reflective cones to funnel the faint light—can detect this blue flash in the atmosphere. Three observatories equipped with Cherenkov telescopes look at the sky during moonless hours of the night: VERITAS in Arizona has an array of four; MAGIC in La Palma, Spain, has two; and HESS in Namibia, Africa, has an array of five.

    CfA/VERITAS, AZ, USA
    CfA/VERITAS, AZ, USA

    MAGIC Cherenkov gamma ray telescope  on the Canary island of La Palma, Spain
    MAGIC Cherenkov gamma ray telescope on the Canary island of La Palma, Spain

    HESS Cherenko Array, located on the Cranz family farm, Göllschau, in Namibia, near the Gamsberg
    HESS Cherenko Array, located on the Cranz family farm, Göllschau, in Namibia, near the Gamsberg

    All three observatories have operated for at least 10 years, revealing a gamma-ray sky to astrophysicists.

    “Those telescopes really have helped to open the window, if you like, on this particular region of the electromagnetic spectrum,” says Paula Chadwick, a gamma-ray astronomer at Durham University in the United Kingdom. But that new window has also hinted at how much more there is to learn.

    “It became pretty clear that what we needed was a much bigger instrument to give us much better sensitivity,” she says. And so gamma-ray scientists have been working since 2005 to develop the next-generation Cherenkov observatory: “a discovery machine,” as Stefan Funk of Germany’s Erlangen Centre for Astroparticle Physics calls it, that will reveal the highest energy objects and events across the entire sky. This is the Cherenkov Telescope Array (CTA), and construction has begun.

    Ironing out the details

    As of now, nearly 1400 researchers and engineers from 32 countries are members of the CTA collaboration, and membership continues to grow. “If we look at the number of CTA members as a function of time, it’s essentially a linear increase,” says CTA spokesperson Werner Hofmann.

    Technology is being developed in laboratories spread across the globe: in Germany, Italy, the United Kingdom, Japan, the United States (supported by the NSF—given the primarily astrophysics science mission of the CTA, it is not a part of the Department of Energy High Energy Physics program), and others. Those nearly 1400 researchers are collaborating and working together to gain a better understanding of how our universe works. “It’s the science that’s got everybody together, got everybody excited, and devoting so much of their time and energy to this,” Chadwick says.

    3
    G. Pérez, IAC, SMM

    The CTA will be split between two locations, with one array in the Northern Hemisphere and a larger one in the Southern Hemisphere. The dual location enables a view of the entire sky.

    CTA’s northern site will host four large telescopes (23 meters wide) and 15 medium telescopes (12 meters wide). The southern site will also host four large telescopes, plus 25 medium and 70 small telescopes (4 meters) that will use three different designs. The small telescopes are equipped to capture the highest energy gamma rays, which emanate, for example, from the center of our galaxy. That high-energy source is visible only from the Southern Hemisphere.

    In July 2015, the CTA Observatory (CTAO) council—the official governing body that acts on behalf of the observatory—chose their top locations in each hemisphere. And in 2016, the council has worked to make those preferences official. On September 19 the council and the Instituto de Astrofísica de Canarias signed an agreement stating that the Roque de los Muchachos Observatory on the Canary Island of La Palma would host the northern array and its 19 constituent telescopes. This same site hosts the current-generation Cherenkov array MAGIC.

    IAC

    Construction of the foundation is progressing at the La Palma site to prepare for a prototype of the large telescope. The telescope itself is expected to be complete in late 2017.

    “It’s an incredibly aggressive schedule,” Hofmann says. “With a bit of luck we’ll have the first of these big telescopes operational at La Palma a year from now.”

    While the large telescope prototype is being built on the La Palma site, the medium and small prototype telescopes are being built in laboratories across the globe and installed at observatories similarly scattered. The prototypes’ optical designs and camera technologies need to be tested in a variety of environments. For example, the team working on one of the small telescope designs has a prototype on the slope of Mount Etna in Sicily. There, volcanic ash sometimes batters the mirrors and attached camera, providing a test to ensure CTA telescopes and instruments can withstand the environment. Unlike optical telescopes, which sit in protective domes, Cherenkov telescopes are exposed to the open air.

    The CTAO council expects to complete negotiations with the European Southern Observatory before the end of 2016 to finalize plans for the southern array. The current plan is to build 99 telescopes in Chile.

    ESO Bloc Icon

    This year, the council also chose the location of the CTA Science Management Center, which will be the central point of data processing, software updates and science coordination. This building, which will be located at Deutsches Elektronen-Synchrotron (also known as DESY) outside of Berlin, has not yet been built, but Hofmann says that should happen in 2018.

    DESY

    The observatory is on track for the first trial observations (essentially, testing) in 2021 and the first regular observations beginning in 2022. How close the project’s construction stays to this outlined schedule depends on funding from nations across the globe. But if the finances remain on track, then in 2024, the full observatory should be complete, and its 118 telescopes will then look for bright flashes of Cherenkov light signaling a violent event or object in the universe.

    See the full article here .

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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 5:54 pm on December 1, 2016 Permalink | Reply
    Tags: Astronomy, , Jodrell Bank Lovell Telescope,   

    From BBC: “Jodrell Bank: New homes would ‘impair’ telescope, rules government” 

    BBC
    BBC

    28 November 2016
    No writer credit found

    Jodrell Bank Lovell Telescope
    Jodrell Bank Lovell Telescope

    Plans to build 120 new homes in Cheshire have been blocked on the grounds they would interfere with the Jodrell Bank radio telescope.

    Gladman Developments had denied the use of household appliances in Goostrey would affect the observatory’s ability to receive radio signals from space.

    But Communities and Local Government Secretary Sajid Javid ruled against the proposed development.

    It would “impair the efficiency” of this “world-class facility”, he said.
    ‘Reasonable protection’

    The proposed site, off Main Road in Goostrey, is 1.95 miles (3.14km) from the observatory, home to the world famous Lovell Telescope.

    Cheshire East councillors rejected the plans last year.

    But the developer appealed the decision claiming there was “no evidence” their plan for 119 extra homes would cause a significant increase in radio interference.

    A public inquiry disagreed, saying the observatory, “as an established world class facility, should be afforded reasonable protection”.

    “This proposal could damage the world-class work being carried out by the observatory,” the government ruling said.

    “The harm to the efficiency of the Radio Telescope carries substantial weight against the proposal.”

    It also concluded the proposal would “be at odds” with the council’s strategy for development in the countryside.

    Cheshire East Councillor Ainsley Arnold said he was “delighted” and glad “the long-term protection of vital scientific work has prevailed over the short-term high demand in housing supply.”

    “Jodrell Bank observatory is a vital asset to this borough, the nation and the international scientific community”.

    The council is “doing everything possible to meet the housing needs of our area” but “this was simply the wrong development in the wrong place,” he said.

    See the full article here .

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  • richardmitnick 5:41 pm on December 1, 2016 Permalink | Reply
    Tags: Astronomy, , Cool Theory on Galaxy Formation, ,   

    From CSIRO: “Cool Theory on Galaxy Formation” 

    CSIRO bloc

    Commonwealth Scientific and Industrial Research Organisation

    2 December 2016
    Mr Andrew Warren
    Communications Advisor · Communications
    Phone: +61 7 3833 5666
    (Mobile) +61 416 277 695
    Email: Andrew.Warren@csiro.au

    Giant galaxies may grow from cold gas that condenses as stars rather than forming in hot, violent mergers.

    1
    © ESO/M. Kornmesser.

    The surprise finding was made with CSIRO and US radio telescopes by an international team including four CSIRO researchers and published in the journal Science today.

    The biggest galaxies are found at the hearts of clusters, huge swarms of galaxies.

    “Until now we thought these giants formed by small galaxies falling together and merging,” team member Professor Ray Norris of CSIRO and Western Sydney University said.

    But the researchers, led by Dr Bjorn Emonts from the Centro de Astrobiología in Spain, saw something very different when they looked at a protocluster, an embryonic cluster, 10 billion light-years away.

    This protocluster was known to have a giant galaxy called the Spiderweb forming at its centre.

    2
    Spiderweb galaxy.http://www.quantumday.com/2014/10/probing-spiderweb-galaxy-cluster-mrc.html

    Dr Emonts’ team found that the Spiderweb is wallowing in a huge cloud of very cold gas that could be up to 100 billion times the mass of our Sun.

    Most of this gas must be hydrogen, the basic material from which stars and galaxies form.

    Earlier work by another team had revealed young stars all across the protocluster. The new finding suggests that “rather than forming from infalling galaxies, the Spiderweb may be condensing directly out of the gas,” according to Professor Norris.

    The astronomers didn’t see the hydrogen gas directly but located it by detecting a tracer gas, carbon monoxide (CO), which is easier to find.

    The Very Large Array [VLA] telescope in the USA showed that most of the CO could not be in the small galaxies in the protocluster, while CSIRO’s Australia Telescope Compact Array [ATCA] saw the large cloud surrounding the galaxies.

    NRAO/VLA, on the Plains of San Agustin fifty miles west of Socorro, NM, USA
    NRAO/VLA, on the Plains of San Agustin fifty miles west of Socorro, NM, USA

    CSIRO ATCA at the Paul Wild Observatory, about 25 km west of the town of Narrabri in rural NSW about 500 km north-west of Sydney, AU
    CSIRO ATCA at the Paul Wild Observatory, about 25 km west of the town of Narrabri in rural NSW about 500 km north-west of Sydney, AU

    “This is the sort of science the Compact Array excels at,” Professor Norris said.

    Co-author Professor Matthew Lehnert from the Institut Astrophysique de Paris described the gas as “shockingly cold” – about minus 200 degrees Celsius.

    “We expected a fiery process – lots of galaxies falling in and heating gas up,” he said.

    Where the carbon monoxide came from is a puzzle.

    “It’s a by-product of previous stars but we cannot say for sure where it came from or how it accumulated in the cluster core,” Dr Emonts said.

    “To find out we’d have to look even deeper into the Universe’s history.”

    CSIRO researchers Ron Ekers, James Allison and Balthasar Indermuehle also contributed to this study of the Spiderweb.

    The Australia Telescope Compact Array is part of the Australia Telescope National Facility, which is funded by the Australian Government for operation as a National Facility managed by CSIRO.

    See the full article here .

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    CSIRO campus

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

     
  • richardmitnick 4:28 pm on December 1, 2016 Permalink | Reply
    Tags: , Astronomy, , II Zw 40, , ,   

    From UCLA: “UCLA astronomers watch star clusters spewing out dust” 

    UCLA bloc

    UCLA

    December 01, 2016
    Katherine Kornei

    1
    In the galaxy II Zw 40, dust (shown in yellow) is strongly associated with clusters of stars (shown in orange). UCLA researchers have used new observations of this galaxy to confirm that these stars are creating enormous amounts of dust. S. M. Consiglio et al., Astrophysical Journal Letters, 2016

    Galaxies are often thought of as sparkling with stars, but they also contain gas and dust. Now, a team led by UCLA astronomers has used new data to show that stars are responsible for producing dust on galactic scales, a finding consistent with long-standing theory. Dust is important because it is a key component of rocky planets such as Earth.

    This research is published online today in the Astrophysical Journal Letters.

    Jean Turner, a UCLA professor in the department of astronomy and physics, her graduate student S. Michelle Consiglio, and two other collaborators observed a galaxy roughly 33 million light-years away. The researchers focused on this galaxy, called “II Zw 40,” because it is vigorously forming stars and therefore useful for testing theories of star formation. “This galaxy has one of the largest star-forming regions in the local universe,” Turner said.

    The researchers, led by Consiglio, obtained images of II Zw 40 using the Atacama Large Millimeter/submillimeter Array telescope. This telescope, located in Chile’s Atacama desert, is composed of an array of 66 individual telescopes that function as a single large observatory.

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

    In 2011, Turner took a three-month sabbatical from UCLA to help prepare the Atacama Array to be used by the astronomical community. “I helped with reducing data and served as astronomer on duty,” she said.

    The telescope is sensitive to light in the millimeter and submillimeter part of the electromagnetic spectrum, just slightly shorter than microwaves. Capturing this kind of light requires a telescope at high altitudes — this one is built on a plateau at 16,400 feet — because “the Earth’s atmosphere is beginning to absorb very strongly at those wavelengths,” Turner said. “All ALMA scientists work at a lower elevation because you can’t think well at that altitude,” she added.

    Consiglio and her team observed the central region of II Zw 40, a part of the galaxy with two young clusters of stars, each containing roughly a million stars. By imaging II Zw 40’s star clusters at different wavelengths, they constructed a map that traced the dust in the galaxy. Astronomical dust — made mostly of carbon, silicon and oxygen — is prevalent in the universe. “If you look at the Milky Way in the sky, it looks kind of patchy and splotchy. That’s due to dust blocking the light,” Turner said.

    The researchers tested whether the location of the galaxy’s dust was consistent with the location of the galaxy’s star clusters. They found that it was: Consiglio and her team showed that II Zw 40’s dust was concentrated within roughly 320 light-years of the star clusters. “The dust is all focused near the double cluster,” Turner said. This observation supported their hypothesis that stars are responsible for producing dust. “The double cluster is a ‘soot factory’ polluting its local environment,” Consiglio said.

    Scientists have long theorized that stars produce dust by expelling the elements fused deep within their interiors, enriching their host galaxies in elements heavier than hydrogen and helium. However, astronomical data have thus far not backed up that claim. “People have looked for this large-scale enrichment of galaxies, but they haven’t seen it before,” Turner said. “We’re seeing galaxy-scale enrichment and we see clearly where it is coming from.”

    The researchers propose that the dust enrichment is so obvious in II Zw 40’s star clusters because they contain large numbers of very young, massive stars, which are the producers of dust. “The evolutionary time scales of these stars are short enough that you see the dust before it has a chance to get dispersed very far from its source,” Turner said. “We’re looking at the best place to see dust enrichment, in large star clusters,” Consiglio added.

    These new results motivate the team to observe more star clusters. “This is a snapshot of a double cluster at one age in one galaxy,” Turner said. “Our goal now is to find other sources and look at them in different stages of evolution to better understand the evolution of these giant star clusters and how they enrich their environment in dust.”

    See the full article here .

    Please help promote STEM in your local schools.

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    UC LA Campus

    For nearly 100 years, UCLA has been a pioneer, persevering through impossibility, turning the futile into the attainable.

    We doubt the critics, reject the status quo and see opportunity in dissatisfaction. Our campus, faculty and students are driven by optimism. It is not naïve; it is essential. And it has fueled every accomplishment, allowing us to redefine what’s possible, time after time.

    This can-do perspective has brought us 12 Nobel Prizes, 12 Rhodes Scholarships, more NCAA titles than any university and more Olympic medals than most nations. Our faculty and alumni helped create the Internet and pioneered reverse osmosis. And more than 100 companies have been created based on technology developed at UCLA.

     
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