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  • richardmitnick 6:07 pm on February 21, 2017 Permalink | Reply
    Tags: , , , , MASTER Global Robotic Network, Supermassive black hole in the center of a galaxy known to astronomers as NGC 2617   

    From EurekaAlert: “Changes of supermassive black hole in the center of NGC 2617 galaxy” 

    eurekaalert-bloc

    EurekaAlert

    20-Feb-2017
    Lomonosov Moscow State University

    Astrophysicists study surprising changes in the appearance of a supermassive black hole.

    1
    Members of the Sternberg Astronomical Institute of the Lomonosov Moscow State University have been studying changes in the appearance of emission from around the supermassive black hole in the center of a galaxy known to astronomers as NGC 2617. The center of this galaxy, underwent dramatic changes in its appearance several years ago: it became much brighter and things that had not been seen before were seen. This sort of dramatic change can give us valuable information for understanding what the surroundings of a giant black hole are like and what is going on near the black hole. The results of these investigations have been published in the Monthly Notices of the Royal Astronomical Society, one of the world’s top-rated astronomical journals.

    Most galaxies such as our own have a giant black hole in their central nuclei. These monstrous holes have masses ranging from a million to a billion times the mass of our sun. The black hole in our galaxy is inactive, but in some galaxies, the black hole is swallowing gas that is spiraling into it and emitting enormous amounts of radiation. These galaxies are called “active galactic nuclei” or AGNs for short. The energy output from around the black holes of these AGNs can exceed that of the hundreds of billions of stars in the rest of the galaxy. Just how these galaxies get their supermassive black holes is a major mystery.

    The nuclei of galaxies where the supermassive black holes are vigorously swallowing gas are classified into two types: those where we get a direct view of the matter spiraling into the black hole at a speed that is thousands of times faster than the speed of sound, and those where the inner regions are obscured by dust and we only see more slowly moving gas much further from the black hole.

    For decades astronomers have wondered why we see the innermost regions of some active galactic nuclei but not others. A popular explanation of the two types of active galactic nuclei is that they are really the same but they appear to be different to us because we are viewing them from different angles. If they are face-on we can see the hot gas spiraling into the black hole directly. If the active galactic nucleus is tilted, then dust around the nucleus blocks our view and we can only see the more slowly moving gas a light year or more away.

    The leader of the international research team involved in the investigation, Viktor Oknyansky, a Senior Researcher at the Sternberg Astronomical Institute of the Lomonosov Moscow State University says: “Cases of object transition from one type to the other turn out to be a definite problem for this orientation model. In 1984 we found a change in the appearance of another active galactic nucleus known as NGC 4151. It was one of few known cases of this kind in the past. We now know of several dozen active galactic nuclei that have changed their type. In our recent study we have focused on one of the best cases — NGC 2617.”

    Oknyansky continues: “In 2013 a team of researchers in the US found that NGC 2617 had changed being an active galaxy where the inner regions were hidden to one where the inner regions were now exposed. We didn’t not know how long it would remain in this new unveiled state. It could last for only a short period of time or, on the other hand, for dozens of years. The title of the paper by the US astronomers was “The man behind the curtain…” When we began our study we didn’t know how long the curtain would remain open, but we’ve titled our paper “The curtain remains open…”, because we are continuing to see into the inner regions of NGC 2617.

    According to the authors there is no accepted explanation so far of what could cause us to start seeing down to the inner regions of an active galactic nucleus when it was previously hidden.

    Viktor Oknyansky comments: “It’s clear that this phenomenon isn’t very rare, on the contrary, we think it’s quite typical. We consider various possible explanations. One is that perhaps a star has come too close to the black hole and has been torn apart. However, the disruption of a star by a black hole is very rare and we don’t think that such events can explain the observed frequency of type changes of active galactic nuclei. Instead we favour a model where the black hole has started swallowing gas more rapidly. As the material spirals in towards the black holes it emits strong radiation. We speculate that this intense radiation destroys some of the dust surrounding the nucleus and permits us to see the inner regions.”

    Oknyansky continues: “Study of these rapid changes of type is very important for understanding what is going on around supermassive black holes that are rapidly swallowing gas. So, what we have concentrated on is getting observations of the various types of radiation emitted by NGC 2617. This has involved a large-scale effort.”

    The observational data for the project were obtained using the MASTER Global Robotic Network operated by Professor Vladimir Lipunov and his team, the new 2.5-m telescope located near Kislovodsk, a 2-m telescope of the observatory in Azerbajan, the Swift X-ray satellite, and some other telescopes. This research has been conducted in cooperation with colleagues from Azerbaijan, the USA, Finland, Chili, Israel and the South Africa.

    1
    MASTER GLOBAL Robotic Net

    NASA/SWIFT Telescope
    NASA/SWIFT Telescope

    See the full article here .

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    EurekAlert!, the premier online news source focusing on science, health, medicine and technology, is a free service for reporters worldwide.

    Since 1996, EurekAlert! has served as the leading destination for scientific organizations seeking to disseminate news to reporters and the public. Today, thousands of reporters around the globe rely on EurekAlert! as a source of ideas, background information, and advance word on breaking news stories.

    More than 1,000 peer-reviewed journals, universities, medical centers, government agencies and public relations firms have used EurekAlert! to distribute their news. EurekAlert! is an authoritative and comprehensive research news source for journalists all over the world.

     
  • richardmitnick 5:40 pm on February 21, 2017 Permalink | Reply
    Tags: , , , Gas giants   

    From Carnegie: “Prediction: More gas-giants will be found orbiting Sun-like stars” 

    Carnegie Institution for Science
    Carnegie Institution for Science

    1
    Boss’ model of a planet-forming disk, which demonstrates that gas giant planets could be found orbiting Sun-like stars at distances similar to Jupiter and Saturn. The disk extends from 4 to 20 times the distance of the Earth from the Sun. You can see the spiral arms forming in the midplane of the disk. The disk instability theory suggests that gas giant planets can form from the clumps seen in the densest regions of the spiral arms.

    February 21, 2017
    No writer credit

    New planetary formation models from Carnegie’s Alan Boss indicate that there may be an undiscovered population of gas giant planets orbiting around Sun-like stars at distances similar to those of Jupiter and Saturn. His work is published by The Astrophysical Journal.

    The population of exoplanets discovered by ongoing planet-hunting projects continues to increase. These discoveries can improve models that predict where to look for more of them.

    The planets predicted by Boss in this study could hold the key to solving a longstanding debate about the formation of our Solar System’s giant planets out of the disk of gas and dust that surrounded the Sun in its youth.

    One theory holds that gas giants form just like terrestrial planets do—by the slow accretion of rocky material from the rotating disk—until the object contains enough material to gravitationally attract a very large envelope of gas around a solid core. The other theory states that gas giant planets form rapidly when the disk gas forms spiral arms, which increase in mass and density until distinct clumps form that coalesce into baby gas giant planets.

    One problem with the first option, called core accretion, is that it can’t explain how gas giant planets form beyond a certain orbital distance from their host stars—a phenomenon that is increasingly found by intrepid planet hunters. However, models of the second theory, called disk instability, have indicated the formation of planets with orbits between about 20 and 50 times the distance between the Earth and the Sun.

    “Given the existence of gas giant planets on such wide orbits, disk instability or something similar must be involved in the creation of at least some exoplanets,” Boss said. “However, whether or not this method could create closer-orbiting gas giant planets remains unanswered.”

    Boss set out to use his modeling tools to learn if gas giant planets can form closer to their host stars by taking a new look at the disk-cooling process. His simulations indicate that there may be a largely unseen population of gas giant planets orbiting Sun-like stars at distances between 6 and 16 times that separating the Earth and the Sun. (For context Jupiter is just over five times as distant from the Sun as Earth is, and Saturn is over nine times as distant.)

    “NASA’s upcoming Wide Field Infrared Survey Telescope [WFIRST]may be ideally suited to test my predictions here,” Boss added.

    NASA/WFIRST
    NASA/WFIRST

    See the full article here .

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    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
  • richardmitnick 5:27 pm on February 21, 2017 Permalink | Reply
    Tags: A candidate for dark matter?, A mobile neutrino detector could be used to determine whether a nuclear reactor is in use, , Determine whether material from a reactor has been repurposed to produce nuclear weapons?, MiniCHANDLER is specifically designed to detect neutrinos' antimatter counterparts antineutrinos, MiniCHANDLER will make history as the first mobile neutrino detector in the US, , , Virginia Tech   

    From Symmetry: “Mobile Neutrino Lab makes its debut” 

    Symmetry Mag

    Symmetry

    02/21/17
    Daniel Garisto

    1
    The Mystery Machine for particles hits the road.

    It’s not as flashy as Scooby Doo’s Mystery Machine, but scientists at Virginia Tech hope that their new vehicle will help solve mysteries about a ghost-like phenomena: neutrinos.

    The Mobile Neutrino Lab is a trailer built to contain and transport a 176-pound neutrino detector named MiniCHANDLER (Carbon Hydrogen AntiNeutrino Detector with a Lithium Enhanced Raghavan-optical-lattice). When it begins operations in mid-April, MiniCHANDLER will make history as the first mobile neutrino detector in the US.

    “Our main purpose is just to see neutrinos and measure the signal to noise ratio,” says Jon Link, a member of the experiment and a professor of physics at Virginia Tech’s Center for Neutrino Physics. “We just want to prove the detector works.”

    Neutrinos are fundamental particles with no electric charge, a property that makes them difficult to detect. These elusive particles have confounded scientists on several fronts for more than 60 years. MiniCHANDLER is specifically designed to detect neutrinos’ antimatter counterparts, antineutrinos, produced in nuclear reactors, which are prolific sources of the tiny particles.

    Fission at the core of a nuclear reactor splits uranium atoms, whose products themselves undergo a process that emits an electron and electron antineutrino. Other, larger detectors such as Daya Bay have capitalized on this abundance to measure neutrino properties.

    MiniCHANDLER will serve as a prototype for future mobile neutrino experiments up to 1 ton in size.

    Link and his colleagues hope MiniCHANDLER and its future counterparts will find answers to questions about sterile neutrinos, an undiscovered, theoretical kind of neutrino and a candidate for dark matter. The detector could also have applications for national security by serving as a way to keep tabs on material inside of nuclear reactors.

    MiniCHANDLER echoes a similar mobile detector concept from a few years ago. In 2014, a Japanese team published results from another mobile neutrino detector, but their data did not meet the threshold for statistical significance. Detector operations were halted after all reactors in Japan were shut down for safety inspections.

    “We can monitor the status from outside of the reactor buildings thanks to [a] neutrino’s strong penetration power,” Shugo Oguri, a scientist who worked on the Japanese team, wrote in an email.

    Link and his colleagues believe their design is an improvement, and the hope is that MiniCHANDLER will be able to better reject background events and successfully detect neutrinos.

    Neutrinos, where are you?

    To detect neutrinos, which are abundant but interact very rarely with matter, physicists typically use huge structures such as Super-Kamiokande, a neutrino detector in Japan that contains 50,000 tons of ultra-pure water.

    Super-Kamiokande Detector, Japan
    Super-Kamiokande Detector, Japan

    Experiments are also often placed far underground to block out signals from other particles that are prevalent on Earth’s surface.

    With its small size and aboveground location, MiniCHANDLER subverts both of these norms.

    The detector uses solid scintillator technology, which will allow it to record about 100 antineutrino interactions per day. This interaction rate is less than the rate at large detectors, but MiniCHANDLER makes up for this with its precise tracking of antineutrinos.

    Small plastic cubes pinpoint where in MiniCHANDLER an antineutrino interacts by detecting light from the interaction. However, the same kind of light signal can also come from other passing particles like cosmic rays. To distinguish between the antineutrino and the riffraff, Link and his colleagues look for multiple signals to confirm the presence of an antineutrino.

    Those signs come from a process called inverse beta decay. Inverse beta decay occurs when an antineutrino collides with a proton, producing light (the first event) and also kicking a neutron out of the nucleus of the atom. These emitted neutrons are slower than the light and are picked up as a secondary signal to confirm the antineutrino interaction.

    “[MiniCHANDLER] is going to sit on the surface; it’s not shielded well at all. So it’s going to have a lot of background,” Link says. “Inverse beta decay gives you a way of rejecting the background by identifying the two-part event.”

    Monitoring the reactors

    Scientists could find use for a mobile neutrino detector beyond studying reactor neutrinos. They could also use the detector to measure properties of the nuclear reactor itself.

    A mobile neutrino detector could be used to determine whether a reactor is in use, Oguri says. “Detection unambiguously means the reactors are in operation—nobody can cheat the status.”

    The detector could also be used to determine whether material from a reactor has been repurposed to produce nuclear weapons. Plutonium, an element used in the process of making weapons-grade nuclear material, produces 60 percent fewer detectable neutrinos than uranium, the primary component in a reactor core.

    “We could potentially tell whether or not the reactor core has the right amount of plutonium in it,” Link says.

    Using a neutrino detector would be a non-invasive way to track the material; other methods of testing nuclear reactors can be time-consuming and disruptive to the reactor’s processes.

    But for now, Link just wants MiniCHANDLER to achieve a simple—yet groundbreaking—goal: Get the mobile neutrino lab running.

    See the full article here .

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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 5:01 pm on February 21, 2017 Permalink | Reply
    Tags: , , , When Rocket Science Meets X-ray Science,   

    From LBNL: “When Rocket Science Meets X-ray Science” 

    Berkeley Logo

    Berkeley Lab

    February 21, 2017
    Glenn Roberts Jr.
    glennemail@gmail.com
    510-486-5582

    Berkeley Lab and NASA collaborate in X-ray experiments to ensure safety, reliability of spacecraft systems.

    1
    Francesco Panerai of Analytical Mechanical Associates Inc., a materials scientist leading a series of X-ray experiments at Berkeley Lab for NASA Ames Research Center, discusses a 3-D visualization (shown on screens) of a heat shield material’s microscopic structure in simulated spacecraft atmospheric entry conditions. The visualization is based on X-ray imaging at Berkeley Lab’s Advanced Light Source. (Credit: Marilyn Chung/Berkeley Lab)

    Note: This is the first installment in a four-part series that focuses on a partnership between NASA and Berkeley Lab to explore spacecraft materials and meteorites with X-rays in microscale detail.

    It takes rocket science to launch and fly spacecraft to faraway planets and moons, but a deep understanding of how materials perform under extreme conditions is also needed to enter and land on planets with atmospheres.

    X-ray science is playing a key role, too, in ensuring future spacecraft survive in extreme environments as they descend through otherworldly atmospheres and touch down safely on the surface.

    Scientists at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) and NASA are using X-rays to explore, via 3-D visualizations, how the microscopic structures of spacecraft heat shield and parachute materials survive extreme temperatures and pressures, including simulated atmospheric entry conditions on Mars.

    Human exploration of Mars and other large-payload missions may require a new type of heat shield that is flexible and can remain folded up until needed.


    Streaking particles collide with carbon fibers in this direct simulation Monte Carlo (DSMC) calculation based on X-ray microtomography data from Berkeley Lab’s Advanced Light Source. NASA is developing new types of carbon fiber-based heat shield materials for next-gen spacecraft. The slow-motion animation represents 2 thousandths of a second. (Credit: Arnaud Borner, Tim Sandstrom/NASA Ames Research Center)

    Candidate materials for this type of flexible heat shield, in addition to fabrics for Mars-mission parachutes deployed at supersonic speeds, are being tested with X-rays at Berkeley Lab’s Advanced Light Source (ALS) and with other techniques.

    LBNL/ALS
    LBNL/ALS

    “We are developing a system at the ALS that can simulate all material loads and stresses over the course of the atmospheric entry process,” said Harold Barnard, a scientist at Berkeley Lab’s ALS who is spearheading the Lab’s X-ray work with NASA.

    The success of the initial X-ray studies has also excited interest from the planetary defense scientific community looking to explore the use of X-ray experiments to guide our understanding of meteorite breakup. Data from these experiments will be used in risk analysis and aid in assessing threats posed by large asteroids.

    The ultimate objective of the collaboration is to establish a suite of tools that includes X-ray imaging and small laboratory experiments, computer-based analysis and simulation tools, as well as large-scale high-heat and wind-tunnel tests. These allow for the rapid development of new materials with established performance and reliability.


    NASA has tested a new type of flexible heat shield, developed through the Adaptive Deployable Entry and Placement Technology (ADEPT) Project, with a high-speed blow torch at its Arc Jet Complex at NASA Ames, and has explored the microstructure of its woven carbon-fiber material at Berkeley Lab. (Credit: NASA Ames)

    This system can heat sample materials to thousands of degrees, subject them to a mixture of different gases found in other planets’ atmospheres, and with pistons stretch the material to its breaking point, all while imaging in real time their 3-D behavior at the microstructure level.

    NASA Ames Research Center (NASA ARC) in California’s Silicon Valley has traditionally used extreme heat tests at its Arc Jet Complex to simulate atmospheric entry conditions.

    Researchers at ARC can blast materials with a giant superhot blowtorch that accelerates hot air to velocities topping 11,000 miles per hour, with temperatures exceeding that at the surface of the sun. Scientists there also test parachutes and spacecraft at its wind-tunnel facilities, which can produce supersonic wind speeds faster than 1,900 miles per hour.

    Michael Barnhardt, a senior research scientist at NASA ARC and principal investigator of the Entry Systems Modeling Project, said the X-ray work opens a new window into the structure and strength properties of materials at the microscopic scale, and expands the tools and processes NASA uses to “test drive” spacecraft materials before launch.

    “Before this collaboration, we didn’t understand what was happening at the microscale. We didn’t have a way to test it,” Barnhardt said. “X-rays gave us a way to peak inside the material and get a view we didn’t have before. With this understanding, we will be able to design new materials with properties tailored to a certain mission.”

    He added, “What we’re trying to do is to build the basis for more predictive models. Rather than build and test and see if it works,” the X-ray work could reduce risk and provide more assurance about a new material’s performance even at the drawing-board stage.

    2
    Francesco Panerai holds a sample of parachute material at NASA Ames Research Center. The screen display shows a parachute prototype (left) and a magnified patch of the material at right. (Credit: Marilyn Chung/Berkeley Lab)

    Francesco Panerai, a materials scientist with NASA contractor AMA Inc. and the X-ray experiments test lead for NASA ARC, said that the X-ray experiments at Berkeley Lab were on samples about the size of a postage stamp. The experimental data is used to improve realistic computer simulations of heat shield and parachute systems.

    “We need to use modern measurement techniques to improve our understanding of material response,” Panerai said. The 3-D X-ray imaging technique and simulated planetary conditions that NASA is enlisting at the ALS provide the best pictures yet of the behavior of the internal 3-D microstructure of spacecraft materials.

    The experiments are being conducted at an ALS experimental station that captures a sequence of images as a sample is rotated in front of an X-ray beam. These images, which provide views inside the samples and can resolve details less than 1 micron, or 1 millionth of a meter, can be compiled to form detailed 3-D images and animations of samples.

    This study technique is known as X-ray microtomography. “We have started developing computational tools based on these 3-D images, and we want to try to apply this methodology to other research areas, too,” he said.

    Learn more about the research partnership between NASA and Berkeley Lab in these upcoming articles, to appear at :

    Feb. 22—The Heat is On: X-rays reveal how simulated atmospheric entry conditions impact spacecraft shielding.
    Feb. 23—A New Paradigm in Parachute Design: X-ray studies showing the microscopic structure of spacecraft parachute fabrics can fill in key details about how they perform under extreme conditions.
    Feb. 24—Getting to Know Meteors Better: Experiments at Berkeley Lab may help assess risks posed by falling Space rocks.

    The Advanced Light Source is a DOE Office of Science User Facility.

    See the full article here .

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    A U.S. Department of Energy National Laboratory Operated by the University of California

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  • richardmitnick 8:07 am on February 21, 2017 Permalink | Reply
    Tags: , , , , , , The thread of star birth   

    From ESA: “The thread of star birth” 

    ESA Space For Europe Banner

    European Space Agency

    1
    Title Star formation on filaments in RCW106
    Released 20/02/2017 9:30 am
    Copyright ESA/Herschel/PACS, SPIRE/Hi-GAL Project. Acknowledgement: UNIMAP / L. Piazzo, La Sapienza – Università di Roma; E. Schisano / G. Li Causi, IAPS/INAF, Italy
    Description

    ESA/Herschel spacecraft
    “ESA/Herschel spacecraft

    Stars are bursting into life all over this image from ESA’s Herschel space observatory. It depicts the giant molecular cloud RCW106, a massive billow of gas and dust almost 12 000 light-years away in the southern constellation of Norma, the Carpenter’s Square.

    Cosmic dust, a minor but crucial ingredient in the interstellar material that pervades our Milky Way galaxy, shines brightly at infrared wavelengths. By tracing the glow of dust with the infrared eye of Herschel, astronomers can explore stellar nurseries in great detail.

    Sprinkled across the image are dense concentrations of the interstellar mixture of gas and dust where stars are being born. The brightest portions, with a blue hue, are being heated by the powerful light from newborn stars within them, while the redder regions are cooler.

    The delicate shapes visible throughout the image are the result of radiation and mighty winds from the young stars carving bubbles and other cavities in the surrounding interstellar material.

    Out of the various bright, blue regions, the one furthest to the left is known as G333.6-0.2 and is one of the most luminous portions of the infrared sky. It owes its brightness to a stellar cluster, home to at least a dozen young and very bright stars that are heating up the gas and dust around them.

    Elongated and thin structures, or filaments, stand out in the tangle of gas and dust, tracing the densest portions of this star-forming cloud. It is largely along these filaments, dotted with many bright, compact cores, that new stars are taking shape.

    Launched in 2009, Herschel observed the sky at far-infrared and submillimetre wavelengths for almost four years. Scanning the Milky Way with its infrared eye, Herschel has revealed an enormous number of filamentary structures, highlighting their universal presence throughout the Galaxy and their role as preferred locations for stellar birth.

    This three-colour image combines Herschel observations at 70 microns (blue), 160 microns (green) and 250 microns (red), and spans over 1º on the long side; north is up and east to the left. The image was obtained as part of Herschel’s Hi-GAL key-project, which imaged the entire plane of the Milky Way in five different infrared bands. A video panorama compiling all Hi-GAL observations was published in April 2016.

    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 7:55 am on February 21, 2017 Permalink | Reply
    Tags: , , , , , , Magnetic mirror design for finding evidence of primordial gravitational waves   

    From ESA: “Magnetic mirror design for finding evidence of primordial gravitational waves” 

    ESA Space For Europe Banner

    European Space Agency

    20 February 2017
    No writer credit

    1
    Title Polarisation of the Cosmic Microwave Background: finer detail
    Released 05/02/2015 3:00 pm
    Copyright ESA and the Planck Collaboration
    Description

    A visualisation of the polarisation of the Cosmic Microwave Background, or CMB, as detected by ESA’s Planck satellite on a small patch of the sky measuring 20º across.

    The CMB is a snapshot of the oldest light in our Universe, imprinted on the sky when the Universe was just 380 000 years old. It shows tiny temperature fluctuations that correspond to regions of slightly different densities, representing the seeds of all future structure: the stars and galaxies of today.

    A small fraction of the CMB is polarised – it vibrates in a preferred direction. This is a result of the last encounter of this light with electrons, just before starting its cosmic journey. For this reason, the polarisation of the CMB retains information about the distribution of matter in the early Universe, and its pattern on the sky follows that of the tiny fluctuations observed in the temperature of the CMB.

    In this image, the colour scale represents temperature differences in the CMB, while the texture indicates the direction of the polarised light. The curly textures are characteristic of ‘E-mode’ polarisation, which is the dominant type for the CMB.

    In this image, both data sets have been filtered to show mostly the signal detected on scales around 20 arcminutes on the sky. This shows the fine structure of the measurement obtained by Planck, revealing fluctuations in both the CMB temperature and polarisation on very small angular scales.

    ESA has backed the development of a ‘metamaterial’ device to sift through the faint afterglow of the Big Bang, to search for evidence of primordial gravitational waves triggered by the rapidly expanding newborn Universe.

    “This technological breakthrough widens the potential for a future follow-on to ESA’s 2009-launched Planck mission, which would significantly increase our detailed understanding of the Universe as it began,” explains Peter de Maagt, heading ESA’s Antennas and Sub-Millimetre Wave section.

    ESA/Planck
    ESA/Planck

    Planck mapped the ‘cosmic microwave background’ (CMB) – leftover light from the creation of the cosmos, subsequently redshifted to microwave wavelengths – across the deep sky in more detail than ever before.

    CMB per ESA/Planck
    CMB per ESA/Planck

    The CMB retains properties of ordinary light, including its tendency to polarise in differing directions – employed in everyday life by polarised sunglasses to cut out glare, or 3D glasses used to see alternating differently polarised cinema images through separate eyes.

    2
    Title Metamaterial-reflective half-wave plate
    Released 10/02/2017 4:16 pm
    Copyright Cardiff University
    Description

    Cardiff University’s magnetic mirror half-wave plate design for b-mode polarisation modulation across wide bandwidths. Less than 1 mm thick, this metamaterial-based design employs a combination of a grid-based ‘artificial magnetic conductor’ and metal ‘perfect electrical conductor’ surfaces. The overall effect is to create a differential phase-shift between orthogonal polarisations equal to 180 degrees. The rotation of the plate causes modulation of the polarisation signal.

    Researchers are now searching for one particular corkscrew polarisation of the CMB, known as ‘B-mode polarisation’, predicted to have been caused by gravitational waves rippling through the early Universe as it underwent exponential expansion – surging from a subatomic singularity to its current vastness.

    Identifying these theorised ‘stretchmarks’ within the CMB would offer solid proof that expansion did indeed occur, bringing cosmologists a big step closer to unifying the physics of the very large and the very small.

    “This would be the holy grail of cosmology,” comments Giampaolo Pisano of Cardiff University, heading the team that built the new prototype B-mode polarisation device for ESA.

    3
    The history of the Universe

    Into what is the universe expanding NASA Goddard, Dana Berry
    Into what is the universe expanding NASA Goddard, Dana Berry

    “Our contribution is only a small bit of the hugely complex instrument that will be necessary to accomplish such a detection. It won’t be easy, not least because it involves only a tiny fraction of the overall CMB radiation.”

    One of the main obstacles in detecting primordial B-modes is additional sources of polarisation located between Earth and the CMB, such as dust within our own galaxy.

    Such polarised foreground contributions have different spectral signatures to that of the CMB, however, enabling their removal if measurements are taken over a large frequency range.

    The challenge is therefore to devise a polarisation modulator that operates across a wide frequency bandwidth with high efficiency.

    “Our new ‘magnetic mirror’-based modulator can do just that, thanks to the quite new approach we adopted,” said Giampaolo Pisano.

    Polarisation modulation is often achieved with rotating ‘half-wave plates’. These induce the rotation of the polarised signals which can ‘stick out’ from the unpolarised background. However, the physical thickness of these devices defines their operational bandwidths, which cannot be too large.

    “Our new solution is based on a combination of metal grids embedded in a plastic substrate – what we call a ‘metamaterial’ – possessing customised electromagnetic properties not found in nature.

    “This flat surface transforms and reflects the signal back like a half-wave plate, facing none of the geometrical constraints of previous designs.”

    The team’s prototype multiband magnetic mirror polarisation modulator measures 20 cm across. Any post-Planck space mission would need one larger than a metre in diameter, its design qualified to survive the harsh space environment. The team are now working on enlarging it.

    “To come so far, the University of Cardiff team has had to develop all the equipment and engineering processes making it possible,” adds Peter. “Their work has been supported through ESA’s long-running Basic Technology Research Programme, serving to investigate promising new ideas to help enable future missions.”

    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 7:35 am on February 21, 2017 Permalink | Reply
    Tags: , , , , , Faintest galaxies ever seen explain the ‘Missing Link’ in the Universe   

    From Ethan Siegel: “Faintest galaxies ever seen explain the ‘Missing Link’ in the Universe” 

    From Ethan Siegel
    2.20.17

    How gravitational magnification allows us to see what we’ve never seen before.

    “The problem is, you’re trying to find these really faint things, but you’re looking behind these really bright things. The brightest galaxies in the universe are in clusters, and those cluster galaxies are blocking the background galaxies we’re trying to observe.” -Rachael Livermore

    To see farther than ever, we point our most powerful space telescopes at a single region and collect light for days.

    1
    One of the most massive, distant galaxy clusters of all, MACS J0717.5+3745, was revealed by the Hubble Frontier Fields program. Image credit: NASA / STScI / Hubble Frontier Fields.

    The Hubble Frontier Fields program focused on massive galaxy clusters, using their gravity to enhance our sight even further.

    2
    Ultra-distant, colliding galaxy clusters have been revealed by the Hubble Frontier Fields program, looking fainter, wider-field and deeper than any other survey before it. Image credit: NASA, ESA, D. Harvey (École Polytechnique Fédérale de Lausanne, Switzerland), R. Massey (Durham University, UK), the Hubble SM4 ERO Team, ST-ECF, ESO, D. Coe (STScI), J. Merten (Heidelberg/Bologna), HST Frontier Fields, Harald Ebeling(University of Hawaii at Manoa), Jean-Paul Kneib (LAM)and Johan Richard (Caltech, USA).

    By warping space, the light from background objects gets magnified, revealing extraordinarily faint galaxies.

    3
    Gravitational lenses, magnifying and distorting a background source, allow us to see fainter, more distant objects than ever before. Image credit: ALMA (ESO/NRAO/NAOJ), L. Calçada (ESO), Y. Hezaveh et al.

    The only problem? The cluster itself is closer and overwhelmingly luminous, making it impossible to tease out the distant signals.

    4
    The overwhelmingly large brightness of the galaxies within a foreground cluster, like Abell S1063, shown here, make it a challenge to use gravitational lensing to identify ultra-faint, ultra-distant background galaxies. Image credit: NASA, ESA, and J. Lotz (STScI).

    Until now. Thanks to a superior new technique devised by Rachael Livermore, light from the foreground cluster galaxies can be modeled and subtracted, revealing faint, distant galaxies never seen before.

    5
    The ultra-distant, lensed galaxy candidate, MACS0647-JD, appears magnified and in three disparate locations thanks to the incredible gravity of the gravitational lens of the foreground cluster, MACS J0647. Image credit: NASA, ESA, M. Postman and D. Coe (STScI), and the CLASH Team.

    With Steven Finkelstein and Jennifer Lotz, Livermore has applied this technique to two Frontier Fields clusters already: Abell 2744 and MACS 0416.

    6
    The galaxy cluster MACS 0416 from the Hubble Frontier Fields, with the mass shown in cyan and the magnification from lensing shown in magenta. Image credit: STScI/NASA/CATS Team/R. Livermore (UT Austin).

    The galaxies that came out were up to 100 times fainter than the dimmest galaxies in the Hubble eXtreme Deep Field, setting a new record.

    7
    The smallest, faintest, most distant galaxies identified in the deepest Hubble image ever taken. This new study has them beat, thanks to stronger gravitational lenses. Image credit: NASA, ESA, R. Bouwens and G. Illingworth (UC, Santa Cruz).

    From when the Universe was less than 10% of its current age, the light from these faint, young galaxies made the Universe transparent.

    8
    The reionization and star-formation history of our Universe, where reionization was driven by these faint, early but theoretically numerous galaxies. At last, thanks to Livermore’s work, we’re discovering them. Image credit: NASA / S.G. Djorgovski & Digital Media Center / Caltech.

    Four more Frontier Fields clusters await, while James Webb, launching next year, will extend this technique even further.

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

    See the full article here .

    Please help promote STEM in your local schools.

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

     
  • richardmitnick 7:15 am on February 21, 2017 Permalink | Reply
    Tags: , Chemosynthesis, , , , Strange Life Has Been Found Trapped Inside These Giant Cave Crystals   

    From Science Alert: “Strange Life Has Been Found Trapped Inside These Giant Cave Crystals” 

    ScienceAlert

    Science Alert

    20 FEB 2017
    BEC CREW

    1
    Alexander Van Driessche/Wikipedia

    A NASA scientist just woke them up.

    Strange microbes have been found inside the massive, subterranean crystals of Mexico’s Naica Mine, and researchers suspect they’ve been living there for up to 50,000 years.

    The ancient creatures appear to have been dormant for thousands of years, surviving in tiny pockets of liquid within the crystal structures. Now, scientists have managed to extract them – and wake them up.

    “These organisms are so extraordinary,” astrobiologist Penelope Boston, director of the NASA Astrobiology Institute, said on Friday at the annual meeting of the American Association for the Advancement of Science (AAAS) in Boston.

    The Cave of Crystals in Mexico’s Naica Mine might look incredibly beautiful, but it’s one of the most inhospitable places on Earth, with temperatures ranging from 45 to 65°C (113 to 149°F), and humidity levels hitting more than 99 percent.

    Not only are temperatures hellishly high, but the environment is also oppressively acidic, and confined to pitch-black darkness some 300 metres (1,000 feet) below the surface.

    2
    Peter Williams/Flickr

    In lieu of any sunlight, microbes inside the cave can’t photosynthesise – instead, they perform chemosynthesis using minerals like iron and sulphur in the giant gypsum crystals, some of which stretch 11 metres (36 feet) long, and have been dated to half a million years old.

    Researchers have previously found life living inside the walls of the cavern and nearby the crystals – a 2013 expedition to Naica reported the discovery of creatures thriving in the hot, saline springs of the complex cave system.

    But when Boston and her team extracted liquid from the tiny gaps inside the crystals and sent them off to be analysed, they realised that not only was there life inside, but it was unlike anything they’d seen in the scientific record.

    They suspect the creatures had been living inside their crystal castles for somewhere between 10,000 and 50,000 years, and while their bodies had mostly shut down, they were still very much alive.

    “Other people have made longer-term claims for the antiquity of organisms that were still alive, but in this case these organisms are all very extraordinary – they are not very closely related to anything in the known genetic databases,” Boston told Jonathan Amos at BBC News.

    What’s perhaps most extraordinary about the find is that the researchers were able to ‘revive’ some of the microbes, and grow cultures from them in the lab.

    “Much to my surprise we got things to grow,” Boston told Sarah Knapton at The Telegraph. “It was laborious. We lost some of them – that’s just the game. They’ve got needs we can’t fulfil.”

    At this point, we should be clear that the discovery has yet to be published in a peer-reviewed journal, so until other scientists have had a chance to examine the methodology and findings, we can’t consider the discovery be definitive just yet.

    The team will also need to convince the scientific community that the findings aren’t the result of contamination – these microbes are invisible to the naked eye, which means it’s possible that they attached themselves to the drilling equipment and made it look like they came from inside the crystals.

    “I think that the presence of microbes trapped within fluid inclusions in Naica crystals is in principle possible,” Purificación López-García from the French National Centre for Scientific Research, who was part of the 2013 study that found life in the cave springs, told National Geographic.

    “[But] contamination during drilling with microorganisms attached to the surface of these crystals or living in tiny fractures constitutes a very serious risk,” she says. I am very skeptical about the veracity of this finding until I see the evidence.”

    That said, microbiologist Brent Christner from the University of Florida in Gainesville, who was also not involved in the research, thinks the claim isn’t as far-fetched as López-García is making it out to be, based on what previous studies have managed with similarly ancient microbes.

    “[R]eviving microbes from samples of 10,000 to 50,000 years is not that outlandish based on previous reports of microbial resuscitations in geological materials hundreds of thousands to millions of years old,” he told National Geographic.

    For their part, Boston and her team say they took every precaution to make sure their gear was sterilised, and cite the fact that the creatures they found inside the crystals were similar, but not identical to those living elsewhere in the cave as evidence to support their claims.

    “We have also done genetic work and cultured the cave organisms that are alive now and exposed, and we see that some of those microbes are similar but not identical to those in the fluid inclusions,” she said.

    Only time will tell if the results will bear out once they’re published for all to see, but if they are confirmed, it’s just further proof of the incredible hardiness of life on Earth, and points to what’s possible out there in the extreme conditions of space.

    See the full article here .

    Please help promote STEM in your local schools.

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  • richardmitnick 5:21 pm on February 20, 2017 Permalink | Reply
    Tags: , , , , , , Structures in the Interstellar Medium   

    From AAS NOVA: “Featured Image: Structures in the Interstellar Medium” 

    AASNOVA

    American Astronomical Society

    20 February 2017
    Susanna Kohler

    1

    This beautiful false-color image (which covers ~57 degrees2; click for the full view!) reveals structures in the hydrogen gas that makes up the diffuse atomic interstellar medium at intermediate latitudes in our galaxy. The image was created by representing three velocity channels with colors — red for gas moving at 7.59 km/s, green for 5.12 km/s, and blue for 2.64 km/s — and it shows the dramatically turbulent and filamentary structure of this gas. This image is one of many stunning, high-resolution observations that came out of the DRAO HI Intermediate Galactic Latitude Survey, a program that used the Synthesis Telescope at the Dominion Radio Astrophysical Observatory in British Columbia to map faint hydrogen emission at intermediate latitudes in the Milky Way.

    Synthesis Telescope at the Dominion Radio Astrophysical Observatory in BC,CA
    Synthesis Telescope at the Dominion Radio Astrophysical Observatory in BC,CA

    The findings from the program were recently published in a study led by Kevin Blagrave (Canadian Institute for Theoretical Astrophysics, University of Toronto); to find out more about what they learned, check out the paper below!
    Citation

    K. Blagrave et al 2017 ApJ 834 126. doi:10.3847/1538-4357/834/2/126

    See the full article here .

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  • richardmitnick 4:56 pm on February 20, 2017 Permalink | Reply
    Tags: , , , Nickel is the key to unlocking the mystery, Why are there different “flavors” of iron around the Solar System?   

    From Carnegie: “Why are there different “flavors” of iron around the Solar System?” 

    Carnegie Institution for Science
    Carnegie Institution for Science

    February 20, 2017
    Reference to Person:
    Anat Shahar

    New work from Carnegie’s Stephen Elardo and Anat Shahar shows that interactions between iron and nickel under the extreme pressures and temperatures similar to a planetary interior can help scientists understand the period in our Solar System’s youth when planets were forming and their cores were created. Their findings are published by Nature Geoscience.

    Earth and other rocky planets formed as the matter surrounding our young Sun slowly accreted. At some point in Earth’s earliest years, its core formed through a process called differentiation—when the denser materials, like iron, sunk inward toward the center. This formed the layered composition the planet has today, with an iron core and a silicate upper mantle and crust.

    Scientists can’t take samples of the planets’ cores. But they can study iron chemistry to help understand the differences between Earth’s differentiation event and how the process likely worked on other planets and asteroids.

    One key to researching Earth’s differentiation period is studying variations in iron isotopes in samples of ancient rocks and minerals from Earth, as well as from the Moon, and other planets or planetary bodies.

    Every element contains a unique and fixed number of protons, but the number of neutrons in an atom can vary. Each variation is a different isotope. As a result of this difference in neutrons, isotopes have slightly different masses. These slight differences mean that some isotopes are preferred by certain reactions, which results in an imbalance in the ratio of each isotope incorporated into the end products of these reactions.

    One outstanding mystery on this front has been the significant variation between iron isotope ratios found in samples of hardened lava that erupted from Earth’s upper mantle and samples from primitive meteorites, asteroids, the Moon, and Mars. Other researchers had suggested these variations were caused by the Moon-forming giant impact or by chemical variations in the solar nebula.

    Elardo and Shahar were able to use laboratory tools to mimic the conditions found deep inside the Earth and other planets in order to determine why iron isotopic ratios can vary under different planetary formation conditions.

    They found that nickel is the key to unlocking the mystery.

    Under the conditions in which the Moon, Mars, and the asteroid Vesta’s cores were formed, preferential interactions with nickel retain high concentrations of lighter iron isotopes in the mantle. However, under the hotter and higher-pressure conditions expected during Earth’s core formation process, this nickel effect disappears, which can help explain the differences between lavas from Earth and other planetary bodies, and the similarity between Earth’s mantle and primitive meteorites.

    “There’s still a lot to learn about the geochemical evolution of planets,” Elardo said. “But laboratory experiments allow us to probe to depths we can’t reach and understand how planetary interiors formed and changed through time.”

    1
    A scanning electron microscope image of one of the experiments in Elardo and Shahar’s paper that shows a bright, semi-spherical metal (representing a core) next to a gray, quenched silicate (representing a magma ocean). Image is courtesy of Stephen Elardo.

    This work was funded by a grant from the National Science Foundation.

    See the full article here .

    Please help promote STEM in your local schools.

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    Carnegie Institution of Washington Bldg

    Andrew Carnegie established a unique organization dedicated to scientific discovery “to encourage, in the broadest and most liberal manner, investigation, research, and discovery and the application of knowledge to the improvement of mankind…” The philosophy was and is to devote the institution’s resources to “exceptional” individuals so that they can explore the most intriguing scientific questions in an atmosphere of complete freedom. Carnegie and his trustees realized that flexibility and freedom were essential to the institution’s success and that tradition is the foundation of the institution today as it supports research in the Earth, space, and life sciences.

    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile.
    6.5 meter Magellan Telescopes located at Carnegie’s Las Campanas Observatory, Chile

     
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