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  • richardmitnick 8:16 pm on February 19, 2019 Permalink | Reply
    Tags: "Citizen Scientist Finds Ancient White Dwarf Star Encircled by Puzzling Rings", Astronomers suspect this could be the first known white dwarf with multiple dust rings, , Astrophysics, , , J0207 is about 3 billion years old based on a temperature just over 10500 degrees Fahrenheit (5800 degrees Celsius), , Whatever process is feeding material into its rings must operate on billion-year timescales, White Dwarf LSPM J0207+3331 or J0207 for short   

    From NASA Goddard Space Flight Center: “Citizen Scientist Finds Ancient White Dwarf Star Encircled by Puzzling Rings” 

    NASA Goddard Banner
    From NASA Goddard Space Flight Center

    Feb. 19, 2019
    Jeanette Kazmierczak
    jeanette.a.kazmierczak@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Md.

    A volunteer working with the NASA-led Backyard Worlds: Planet 9 project has found the oldest and coldest known white dwarf — an Earth-sized remnant of a Sun-like star that has died — ringed by dust and debris. Astronomers suspect this could be the first known white dwarf with multiple dust rings.

    The star, LSPM J0207+3331 or J0207 for short, is forcing researchers to reconsider models of planetary systems and could help us learn about the distant future of our solar system.

    “This white dwarf is so old that whatever process is feeding material into its rings must operate on billion-year timescales,” said John Debes, an astronomer at the Space Telescope Science Institute in Baltimore. “Most of the models scientists have created to explain rings around white dwarfs only work well up to around 100 million years, so this star is really challenging our assumptions of how planetary systems evolve.”

    A paper detailing the findings, led by Debes, was published in the Feb. 19 issue of The Astrophysical Journal Letters.

    1
    In this illustration, an asteroid (bottom left) breaks apart under the powerful gravity of LSPM J0207+3331, the oldest, coldest white dwarf known to be surrounded by a ring of dusty debris. Scientists think the system’s infrared signal is best explained by two distinct rings composed of dust supplied by crumbling asteroids. Credits: NASA’s Goddard Space Flight Center/Scott Wiessinger.

    J0207 is located around 145 light-years away in the constellation Capricornus. White dwarfs slowly cool as they age, and Debes’ team calculated J0207 is about 3 billion years old based on a temperature just over 10,500 degrees Fahrenheit (5,800 degrees Celsius). A strong infrared signal picked up by NASA’s Wide-field Infrared Survey Explorer (WISE) mission — which mapped the entire sky in infrared light — suggested the presence of dust, making J0207 the oldest and coldest white dwarf with dust yet known.

    NASA Wise Telescope

    Previously, dust disks and rings had only been observed surrounding white dwarfs about one-third J0207’s age.

    When a Sun-like star runs out of fuel, it swells into a red giant, ejects at least half of its mass, and leaves behind a very hot white dwarf. Over the course of the star’s giant phase, planets and asteroids close to the star become engulfed and incinerated. Planets and asteroids farther away survive, but move outward as their orbits expand. That’s because when the star loses mass, its gravitational influence on surrounding objects is greatly reduced.

    This scenario describes the future of our solar system. Around 5 billion years from now, Mercury, then Venus and possibly Earth will be swallowed when the Sun grows into a red giant. Over hundreds of thousands to millions of years, the inner solar system will be scrubbed clean, and the remaining planets will drift outward.

    Yet some white dwarfs — between 1 and 4 percent — show infrared emission indicating they’re surrounded by dusty disks or rings. Scientists think the dust may arise from distant asteroids and comets kicked closer to the star by gravitational interactions with displaced planets. As these small bodies approach the white dwarf, the star’s strong gravity tears them apart in a process called tidal disruption. The debris forms a ring of dust that will slowly spiral down onto the surface of the star.

    J0207 was found through Backyard Worlds: Planet 9, a project led by Marc Kuchner, a co-author and astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, that asks volunteers to sort through WISE data for new discoveries.

    Melina Thévenot, a co-author and citizen scientist in Germany working with the project, initially thought the infrared signal was bad data. She was searching through the ESA’s (European Space Agency’s) Gaia archives for brown dwarfs, objects too large to be planets and too small to be stars, when she noticed J0207. When she looked at the source in the WISE infrared data, it was too bright and too far away to be a brown dwarf. Thévenot passed her findings along to the Backyard Worlds: Planet 9 team. Debes and Kuchner contacted collaborator Adam Burgasser at the University of California, San Diego to obtain follow-up observations with the Keck II telescope at the W. M. Keck Observatory in Hawaii.

    Keck 2 telescope Maunakea Hawaii USA, 4,207 m (13,802 ft)

    “That is a really motivating aspect of the search,” said Thévenot, one of more than 150,000 citizen scientists on the Backyard Worlds project. “The researchers will move their telescopes to look at worlds you have discovered. What I especially enjoy, though, is the interaction with the awesome research team. Everyone is very kind, and they are always trying to make the best out of our discoveries.”

    The Keck observations helped confirm J0207’s record-setting properties. Now scientists are left to puzzle how it fits into their models.

    3
    Citizen scientists working on Backyard Worlds: Planet 9 scrutinize “flipbooks” of images from NASA’s Wide-field Infrared Survey Explorer. This animation shows a flipbook containing the ring-bearing white dwarf LSPM J0207+3331 (circled).
    Credits: Backyard Worlds: Planet 9/NASA’s Goddard Space Flight Center

    Debes compared the population of asteroid belt analogs in white dwarf systems to the grains of sand in an hourglass. Initially, there’s a steady stream of material. The planets fling asteroids inward towards the white dwarf to be torn apart, maintaining a dusty disk. But over time, the asteroid belts become depleted, just like grains of sand in the hourglass. Eventually, all the material in the disk falls down onto the surface of the white dwarf, so older white dwarfs like J0207 should be less likely to have disks or rings.

    J0207’s ring may even be multiple rings. Debes and his colleagues suggest there could be two distinct components, one thin ring just at the point where the star’s tides break up the asteroids and a wider ring closer to the white dwarf. Follow-up with future missions like NASA’s James Webb Space Telescope may help astronomers tease apart the ring’s constituent parts.

    “We built Backyard Worlds: Planet 9 mostly to search for brown dwarfs and new planets in the solar system,” Kuchner said. “But working with citizen scientists always leads to surprises. They are voracious — the project just celebrated its second birthday, and they’ve already discovered more than 1,000 likely brown dwarfs. Now that we’ve rebooted the website with double the amount of WISE data, we’re looking forward to even more exciting discoveries.”

    Backyard Worlds: Planet 9 is a collaboration between NASA, the American Museum of Natural History in New York, Arizona State University, National Optical Astronomy Observatory, the Space Telescope Science Institute in Baltimore, the University of California San Diego, Bucknell University, the University of Oklahoma, and Zooniverse, a collaboration of scientists, software developers and educators who collectively develop and manage citizen science projects on the internet.

    NASA’s Jet Propulsion Laboratory in Pasadena, California, manages and operates WISE for NASA’s Science Mission Directorate. The WISE mission was selected competitively under NASA’s Explorers Program managed by the agency’s Goddard Space Flight Center. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colorado. Placed in hibernation in 2011, the spacecraft was reactivated in 2013 and renamed NEOWISE. Science operations and data processing take place at the Infrared Processing and Analysis Center at Caltech, which manages JPL for NASA.

    For more information about Backyard Worlds: Planet 9, visit: http://backyardworlds.org

    For more information about NASA’s WISE mission, visit: http://www.nasa.gov/wise

    See the full article here.


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    NASA’s Goddard Space Flight Center is home to the nation’s largest organization of combined scientists, engineers and technologists that build spacecraft, instruments and new technology to study the Earth, the sun, our solar system, and the universe.

    Named for American rocketry pioneer Dr. Robert H. Goddard, the center was established in 1959 as NASA’s first space flight complex. Goddard and its several facilities are critical in carrying out NASA’s missions of space exploration and scientific discovery.


    NASA/Goddard Campus

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  • richardmitnick 3:58 pm on February 19, 2019 Permalink | Reply
    Tags: A simplified version of that interface will make some of that data accessible to the public, , Astrophysics, , , Every 40 seconds LSST’s camera will snap a new image of the sky, Hundreds of computer cores at NCSA will be dedicated to this task, International data highways, LSST Data Journey, , National Center for Supercomputing Applications at the University of Illinois Urbana-Champaign, NCSA will be the central node of LSST’s data network, , , The two data centers NCSA and IN2P3 will provide petascale computing power corresponding to several million billion computing operations per second, They are also developing machine learning algorithms to help classify the different objects LSST finds in the sky   

    From Symmetry: “An astronomical data challenge” 

    Symmetry Mag
    From Symmetry

    1
    Illustration by Sandbox Studio, Chicago with Ana Kova

    02/19/19
    Manuel Gnida

    The Large Synoptic Survey Telescope will manage unprecedented volumes of data produced each night.

    LSST


    LSST Camera, built at SLAC



    LSST telescope, currently under construction on the El Peñón peak at Cerro Pachón Chile, a 2,682-meter-high mountain in Coquimbo Region, in northern Chile, alongside the existing Gemini South and Southern Astrophysical Research Telescopes.

    The Large Synoptic Survey Telescope—scheduled to come online in the early 2020s—will use a 3.2-gigapixel camera to photograph a giant swath of the heavens. It’ll keep it up for 10 years, every night with a clear sky, creating the world’s largest astronomical stop-motion movie.

    The results will give scientists both an unprecedented big-picture look at the motions of billions of celestial objects over time, and an ongoing stream of millions of real-time updates each night about changes in the sky.

    3
    Illustration by Sandbox Studio, Chicago with Ana Kova

    Accomplishing both of these tasks will require dealing with a lot of data, more than 20 terabytes each day for a decade. Collecting and storing the enormous volume of raw data, turning it into processed data that scientists can use, distributing it among institutions all over the globe, and doing all of this reliably and fast requires elaborate data management and technology.

    International data highways

    This type of data stream can be handled only with high-performance computing, the kind available at the National Center for Supercomputing Applications at the University of Illinois, Urbana-Champaign.

    NCSA U Illinois Urbana-Champaign Blue Waters Cray Linux XE/XK hybrid machine supercomputer

    Unfortunately, the U of I is a long way from Cerro Pachón, the remote Chilean mountaintop where the telescope will actually sit.

    But a network of dedicated data highways will make it feel like the two are right next door.

    LSST Data Journey,Illustration by Sandbox Studio, Chicago with Ana Kova

    Every 40 seconds, LSST’s camera will snap a new image of the sky. The camera’s data acquisition system will read out the data, and, after some initial corrections, send them hurtling down the mountain through newly installed high-speed optical fibers. These fibers have a bandwidth of up to 400 gigabits per second, thousands of times larger than the bandwidth of your typical home internet.

    Within a second, the data will arrive at the LSST base site in La Serena, Chile, which will store a copy before sending them to Chile’s capital, Santiago.

    From there, the data will take one of two routes across the ocean.

    The main route will lead them to São Paolo, Brazil, then fire them through cables across the ocean floor to Florida, which will pass them to Chicago, where they will finally be rerouted to the NCSA facility at the University of Illinois.

    If the primary path is interrupted, the data will take an alternative route through the Republic of Panama instead of Brazil. Either way, the entire trip—covering a distance of about 5000 miles—will take no more than 5 seconds.

    Curating LSST data for the world

    NCSA will be the central node of LSST’s data network. It will archive a second copy of the raw data and maintain key connections to two US-based facilities, the LSST headquarters in Tucson, which will manage science operations, and SLAC National Accelerator Laboratory in Menlo Park, California, which will provide support for the camera. But NCSA will also serve as the main data processing center, getting raw data ready for astrophysics research.

    NCSA will prepare the data at two speeds: quickly, for use in nightly alerts about changes to the sky, and at a more leisurely pace, for release as part of the annual catalogs of LSST data.

    6
    Illustration by Sandbox Studio, Chicago with Ana Kova

    Alert production has to be quick, to give scientists at LSST and other instruments time to respond to transient events, such as a sudden flare from an active galaxy or dying star, or the discovery of a new asteroid streaking across the firmament. LSST will send out about 10 million of these alerts per night, each within a minute after the event.

    Hundreds of computer cores at NCSA will be dedicated to this task. With the help of event brokers—software that facilitates the interaction with the alert stream—everyone in the world will be able to subscribe to all or a subset of these alerts.

    NCSA will share the task of processing data for the annual data releases with IN2P3, the French National Institution of Nuclear and Particle Physics, which will also archive a copy of the raw data.

    3

    The two data centers will provide petascale computing power, corresponding to several million billion computing operations per second.

    7
    Illustration by Sandbox Studio, Chicago with Ana Kova

    The releases will be curated catalogs of billions of objects containing calibrated images and measurements of object properties, such as positions, shapes and the power of their light emissions. To pull these details from the data, LSST’s data experts are creating advanced software for image processing and analysis. They are also developing machine learning algorithms to help classify the different objects LSST finds in the sky.

    Annual data releases will be made available to scientists in the US and Chile and institutions supporting LSST operations.

    Last but not least, LSST’s data management team is working on an interface that will make it easy for scientists to use the data LSST collects. What’s even better: A simplified version of that interface will make some of that data accessible to the public.

    See the full article here .


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    Symmetry is a joint Fermilab/SLAC publication.


     
  • richardmitnick 2:28 pm on February 19, 2019 Permalink | Reply
    Tags: "Extreme Radiation Could Strip Exoplanets of their Atmospheres", , Astrophysics, , , , , The exoplanet WASP-69b   

    From IAC via Discover Magazine: “Extreme Radiation Could Strip Exoplanets of their Atmospheres” 

    IAC

    From Instituto de Astrofísica de Canarias – IAC

    via

    DiscoverMag

    Discover Magazine

    December 6, 2018
    Amber Jorgenson

    1
    This artist illustration shows WASP-69b, which sits about 163 light years from Earth, orbiting its host star. (Credit: Gabriel Perez Diaz, SMM (IAC))

    If orbiting just 4 million miles from your fiery host star wasn’t bad enough, things might have just gotten even worse.

    New research shows that stars emitting high levels of ultraviolet (UV) radiation could strip the atmospheres of their ultra-close exoplanets. While observing gas giants that orbit exceptionally close to their host stars, astronomers found that those bombarded with radiation were losing helium from their atmospheres. These results, which were published in multiple studies today in the journals Science and and Astronomy & Astrophysics, could help researchers understand the evolution of planetary atmospheres, and also determine if extreme radiation could be peeling gas giants’ layers of clouds away to leave them as barren, rocky objects.

    Follow the Trail

    Astronomers from the Instituto de Astrofísica de Canarias (IAC) in the Canary Islands came across this strange phenomenon when they observed the exoplanet WASP-69b pass in front of its host star. During its transit, which takes just 3.9 days, the Jupiter-sized planet caused the star’s light to briefly dim, allowing researchers to home in on the orbiting object.

    Planet transit. NASA/Ames

    They used the CARMENES instrument at Spain’s Calar Alto Observatory to break down the planet’s light into visible and near infrared wavelengths — revealing the chemical elements that make up its atmosphere. It was then that they noticed a strange, comet-like tail of particles escaping from the planet.

    CARMENES spectrograph, mounted on the Calar Alto 3.5 meter Telescope, located in Almería province in Spain on Calar Alto, a 2,168-meter-high (7,113 ft) mountain in Sierra de Los Filabres


    Calar Alto 3.5 meter Telescope, located in Almería province in Spain on Calar Alto, a 2,168-meter-high (7,113 ft) mountain in Sierra de Los Filabres

    “We observed a stronger and longer-lasting dimming of the starlight in a region of the spectrum where helium gas absorbs light,” said the WASP-69b study’s lead author, Lisa Nortmann of the IAC, in a news release. “The longer duration of this absorption allows us to infer the presence of a tail.”

    This loss of helium, the second-most abundant element in gas giants, wasn’t an isolated incident, either. Using similar methods, the team studied four other planets that orbit extremely close to their host stars: gas giant KELT-9b, Neptune-sized GJ 436b, and hot Jupiter’s HD 189733b and HD 209458b.

    While helium wasn’t seen leaving the atmospheres of KELT-9b, GJ 436b or HD 209458b, the group did see a balloon of helium surrounding, and escaping from, HD 189733b.

    Wondering why these two planets were losing parts of their outer atmospheres, they turned to ESA’s Multi-Mirror X-Ray Mission (ESA XMM-Newton) for data about their host stars.

    ESA/XMM Newton

    The results showed that both HD 189733b and WASP-69b’s host stars were dangerously active — expelling much more UV radiation than the other host stars.

    And in yet another instance, astronomers from the University of Geneva detected a balloon of helium escaping the atmosphere of HAT-P-11b, whose nearby host star also emits high amounts of UV radiation. Their results were published today in the journal Science.

    Gas Giant Annihilation?

    These correlations lead researchers to believe that massive amounts of UV radiation are energizing helium particles, causing them to escape from the atmosphere and fly out into space. And once these gaseous envelopes have been completely stripped, all that’s left are the dense, rocky corpses of former gas giants. Follow-up studies will be needed to verify this theory, but thankfully, infrared spectrographs like CARMENES are making atmospheric observations a bit easier.

    “In the past, studies of atmospheric escape, like the one we have seen in WASP-69b, were based on space-borne observations of hydrogen in the far ultraviolet, a spectral region of very limited access and strongly affected by interstellar absorption,” said University of Hamburg researcher Michael Salz, who authored the Astronomy & Astrophysics paper about HD 189733b. “Our results show that helium is a very promising new tracer to study atmospheric escape in exoplanets.”

    And if this theory proves true, astronomers could use it to further compare the atmospheres of exoplanets, gain insight into their evolutions and shed light on the peculiar planets that sit a little too close to their host stars.

    See the full article here .

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    Please help promote STEM in your local schools.

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    The Instituto de Astrofísica de Canarias(IAC) is an international research centre in Spain which comprises:

    The Instituto de Astrofísica, the headquarters, which is in La Laguna (Tenerife).
    The Centro de Astrofísica en La Palma (CALP)
    The Observatorio del Teide (OT), in Izaña (Tenerife).

    These centres, with all the facilities they bring together, make up the European Northern Observatory(ENO).

    The IAC is constituted administratively as a Public Consortium, created by statute in 1982, with involvement from the Spanish Government, the Government of the Canary Islands, the University of La Laguna and Spain’s Science Research Council (CSIC).

    The International Scientific Committee (CCI) manages participation in the observatories by institutions from other countries. A Time Allocation Committee (CAT) allocates the observing time reserved for Spain at the telescopes in the IAC’s observatories.

    The exceptional quality of the sky over the Canaries for astronomical observations is protected by law. The IAC’s Sky Quality Protection Office (OTPC) regulates the application of the law and its Sky Quality Group continuously monitors the parameters that define observing quality at the IAC Observatories.

    The IAC’s research programme includes astrophysical research and technological development projects.

    The IAC is also involved in researcher training, university teaching and outreachactivities.

    The IAC has devoted much energy to developing technology for the design and construction of a large 10.4 metre diameter telescope, the ( Gran Telescopio CANARIAS, GTC), which is sited at the Observatorio del Roque de los Muchachos.

    Gran Telescopio Canarias at the Roque de los Muchachos Observatory on the island of La Palma, in the Canaries, Spain, sited on a volcanic peak 2,267 metres (7,438 ft) above sea level

     
  • richardmitnick 1:29 pm on February 19, 2019 Permalink | Reply
    Tags: "First Evidence of a Giant Exoplanet Collision", , Astrophysics, , , , , Kepler-107 system, Kepler-107b and Kepler-107c, The innermost planet Kepler-107b is about 3.5 times as massive as Earth while Kepler-107c which sits farther out is a whopping 9.4 times as massive as Earth, The researchers argue that the denser planet Kepler-107c likely experienced a massive collision with a third unknown planet at some point in its past, Though astronomers have never confirmed a collision between exoplanets in another star system before there is evidence that a similar cosmic crash occurred in our own solar system [Earth and Thea whic   

    From Discover Magazine: “First Evidence of a Giant Exoplanet Collision” 

    DiscoverMag

    From Discover Magazine

    February 18, 2019
    Jake Parks

    1
    A planetary collision is exactly as bad as you would imagine. Unlike an asteroid impact, there’s not just a crater left behind. Instead, such a massive crash causes the surviving world to be stripped of much of its lighter elements, leaving behind an overly dense core. [Thea crashes into Earth] (Credit: NASA/JPL-Caltech)

    For the first time ever, astronomers think they’ve discovered an exoplanet that survived a catastrophic collision with another planet. And according to the new research, which was published Feb. 4, in the journal Nature Astronomy, the evidence for the impact comes from two twin exoplanets that seem to be more fraternal than identical.

    Mass Matters

    The pair of planets in question orbit a Sun-like star (along with two other planets) in the Kepler-107 system, which is located roughly 1,700 light-years away in the constellation Cygnus the Swan.

    Known as Kepler-107b and Kepler-107c, these planets have nearly identical sizes (both have a radius of roughly 1.5 times that of Earth), yet one planet is nearly three times as massive as the other. The innermost planet, Kepler-107b, is about 3.5 times as massive as Earth, while Kepler-107c, which sits farther out, is a whopping 9.4 times as massive as Earth.

    This means the inner planet, Kepler-107b, has an Earth-like density of around 5.3 grams per cubic centimeter, while the more distant Kepler-107c has a density of around 12.6 grams per cubic centimeter — which is extremely dense, even for an alien world. (For reference, water has a density of 1 gram per cubic centimeter.)

    This perplexing density discrepancy left researchers scratching their heads. How could two equally sized exoplanets in the same system (and at nearly the same orbital distance) have such different compositions?

    The Cause

    To determine exactly why Kepler-107c is so dense, first the researchers considered what they already knew. Previous research has shown that intense stellar radiation can strip the atmosphere from a planet that sits too near its host star. But if the innermost planet lost its lighter atmospheric elements, it should be more dense than its twin, not less. According to the study, this would “make the more-irradiated and less-massive planet Kepler-107b denser than Kepler-107c,” which is clearly not the case.

    However, there is another way that a planet can lose a lot of mass: by getting smacked with another planet. And this is exactly what the researchers think happened to Kepler-107c.

    The researchers argue that the denser planet, Kepler-107c, likely experienced a massive collision with a third, unknown planet at some point in its past. Such a gigantic impact, the study says, would have stripped the lighter silicate mantle from Kepler-107c, leaving behind an extremely dense, iron-rich core. According to the study, Kepler-107c could be as much as 70 percent iron.

    Because the mass and radius of Kepler-107c matches what would be expected from a giant planetary impact, the researchers are fairly confident that the collisional scenario they’ve outlined in their paper is accurate; however, they still need to confirm their hypothesis. If proven correct, this new find would become the first-ever evidence of a planetary collision outside our solar system.

    Closer to Home

    Though astronomers have never confirmed a collision between exoplanets in another star system before, there is evidence that a similar cosmic crash occurred in our own solar system. In fact, a leading theory about the formation of the Moon is that it formed when a small protoplanet [Thea, roughly the size of Mars] rammed into early Earth.

    By analyzing lunar samples returned by the Apollo missions, scientists learned that the composition of Moon rocks is very similar to that of Earth’s mantle. Furthermore, the Moon is severely lacking in volatile elements, which boil away at high temperatures. Taken together, along with a few other lines of evidence, this indicates the Moon may have formed when a very large object (roughly the size of Mars) struck Earth with a glancing blow early in the solar system’s history, some 4.6 billion years ago.

    This mash-up melted and tore off some of the outer layers of Earth, which may have temporarily formed Saturn-like rings around our planet. Over time, much of this ejected material drifted back to Earth’s surface, but there was still enough debris left in orbit that it eventually coagulated and formed the Moon.

    With the discovery of Kepler-107c, it seems planet-shattering impacts are not just a sci-fi trope, but instead may occur much more frequently than we once thought. And with the long-anticipated launch of the James Webb Space Telescope coming up in March 2021, it may only be a few more years until they start to reveal themselves en masse, so be sure to stay tuned.

    See the full article here .

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    Please help promote STEM in your local schools.

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  • richardmitnick 12:42 pm on February 19, 2019 Permalink | Reply
    Tags: "Interactive space simulation for nanosatellites", , Astrophysics, , , , Online ‘beeApp’ software, Open Cosmos mission simulator, Pioneer partner Open Cosmos   

    From European Space Agency: “Interactive space simulation for nanosatellites” 

    ESA Space For Europe Banner

    From European Space Agency

    19 February 2019

    1
    Open Cosmos mission simulator

    Pioneer partner Open Cosmos are taking mission development to a new dimension, using a virtual reality-like simulation that replicates life in orbit for space technologies.

    Through an innovative combination of a plug-and-play test platform and software, the UK Harwell-based SME is slashing the time it takes for space missions to be designed and qualified for launch.

    Their online ‘beeApp’ software helps define a full space mission from the ground up, including selection of launchers, ground stations and satellite size.

    Based on those parameters, it runs simulations on the orbits, amount of power received by the satellite from the sun, and when it can communicate with the ground. This data is then used to create the optimal mission profile.

    Once that has been decided, their ‘beeKit’ hardware emulates the size, on-board computer and electrical interfaces of a real satellite, to facilitate the design and testing of the actual payloads.

    When linked, these two tools can simulate the mission in space, and how the payload will perform.

    The beeApp simulates the amount of available solar power, the ground station passes and the payload’s modes of operation and plays it back to the real payload installed in the beeKit.

    That then records the behaviour of the payload as if it was in orbit, providing the mission owners with the data they need to either improve the design or proceed with the mission as is.

    Moreover, the kit hardware is a match for Open Cosmos’ beeSat operational platform, and can be tested along with the payload for the usual mechanical space-qualifying tests, such as vibration and thermal vacuum testing.

    2
    Open Cosmos mission simulator
    Released 19/02/2019
    Copyright Open Cosmos
    The Open Cosmos beeApp application defines a full space mission, including selection of launchers, ground stations and satellite sizes. Based on those parameters, the software simulates the orbits, the amount of power received by the satellite from the sun, when it can see a ground segment and communicate with the Earth, or pass over a specific region. The Open Cosmos beeKit satellite hardware emulates the size, the on-board computer and electrical interfaces of a real satellite, to facilitate the testing of payloads. These payloads can be anything, ranging from Earth Observation, scientific instruments and telecommunication, including proven telecommunications technology or new technology demonstrations.

    The two tools can be linked together to simulate a mission with a real payload. The mission definition software simulates the amounts of available solar power, the ground station passes and the modes of operation of the payload and plays it back to the real payload. It then records the behaviour of the payload as if it was in orbit.

    The company developed the tools under the ‘SAPION’ project of ESA’s ARTES Pioneer programme.

    This means that after the payload has proven to be able to withstand the replicated conditions of launch and space in the beeKit, it can immediately be integrated with the beeSat spacecraft platform, ready for the real thing.

    Open Cosmos then takes care of all technical, legal, logistical and operational processes to bring the payload into orbit at minimal cost.

    The company developed the tools under the ‘SAPION’ project of ESA’s ARTES Pioneer programme.

    Khalil Kably, ESA Pioneer Programme Manager, said: “Pioneer is designed to support companies like Open Cosmos to provide in-orbit validation for other parties as what we call Space Mission Providers.

    “Our purpose is to de-risk our partners’ investments to answer market needs, and we saw a real need to reduce the barriers that can impede the development of disruptive ideas and help Europe’s space sector remain at the cutting edge of technological innovation.”

    Dani Sors, Open Cosmos Head of Customer Success and Florian Deconinck, Head of Strategic Partnerships presented their beeApp and beeKit tools to an audience of ESA experts and Member State delegates at ESA ECSAT on Harwell Campus, UK, on 6 February.

    Catherine Mealing-Jones, Director of Growth, UK Space Agency, said: “The UK is the largest funder of satellite telecommunications research and applications through ESA. We continue to work closely with partners across Europe and the rest of the world to help space start-ups like Open Cosmos transform their exciting ideas into commercial realities, resulting in jobs, growth and innovation throughout the UK.”

    Remco Timmermans, Open Cosmos Head of Communications, said: “Open Cosmos makes space accessible to new players, using new technology, in the shortest timeframes currently possible. We support anything from Earth observation, scientific instruments, telecommunications or new technology demonstrations, and can get a payload in orbit in much less than the usual time and at a fraction of the cost.

    “There is a broad community of people with ambitious ideas struggling to get to orbit. Open Cosmos partners with that community to realise their space mission. The Open Cosmos Call to Orbit, supported by ESA, makes the beeApp and beeKit available for free, to start building the missions of tomorrow.

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings
    Please help promote STEM in your local schools.

    Stem Education Coalition

    The 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.

    ESA50 Logo large

     
  • richardmitnick 12:05 pm on February 19, 2019 Permalink | Reply
    Tags: "Astronomers detect hundreds of thousands of previously unknown galaxies", ASTRON Europe, , , Astrophysics, , ,   

    From University of Oxford: “Astronomers detect hundreds of thousands of previously unknown galaxies” 

    U Oxford bloc

    From University of Oxford

    19 Feb 2019

    1
    ox.ac.uk

    A major new radio sky survey has revealed hundreds of thousands of previously undetected galaxies, shedding new light on many research areas including the physics of black holes and how clusters of galaxies evolve.

    An international team of more than 200 astronomers from 18 countries, including researchers from the University of Oxford, has published the first phase of the survey at unprecedented sensitivity using the Low Frequency Array (LOFAR) telescope.

    ASTRON LOFAR Radio Antenna Bank, Netherlands


    SKA LOFAR core (“superterp”) near Exloo, Netherlands

    Radio astronomy reveals processes in the Universe that we cannot see with optical instruments. In this first part of the sky survey, LOFAR observed a quarter of the northern hemisphere at low radio frequencies. Today around ten percent of that data is being made public. It maps three hundred thousand sources, almost all of which are galaxies in the distant Universe; their radio signals have travelled billions of light years before reaching Earth.

    Dr Leah Morabito, from Oxford Astrophysics said: ‘We will be able to identify hidden black holes, study individual clouds of star formation in nearby galaxies, and understand what jets from black holes look like in the most distant galaxies.’

    The energy output in these radio jets plays a crucial role in controlling the conversion of gas into stars in their surrounding galaxies.

    Clusters of galaxies are ensembles of hundreds to thousands of galaxies. It has been known for decades that when two clusters of galaxies merge, they can produce radio emission spanning millions of light years. This emission is thought to come from particles that are accelerated during the merger process. New research using LOFAR is beginning to show this emission at previously undetected levels from clusters of galaxies that are not merging. This means that there are phenomena other than merger events that can trigger particle accelerations over huge scales.

    LOFAR produces enormous amounts of data. The equivalent of ten million DVDs of data has been processed to create the low-frequency radio sky map. The survey was made possible by a mathematical breakthrough in the way we understand interferometry.

    The LOFAR telescope is unique in its capabilities to map the sky in fine detail at metre wavelengths and is considered to be the world’s leading telescope of its type. The European network of radio antennas spans seven countries and includes the UK station at STFC RAL Space’s Chilbolton Observatory in Hampshire.

    ASTRON LOFAR European Map

    The signals from all of the stations are combined to make the radio images. This effectively gives astronomers a much larger telescope than it is practical to build – and the bigger the telescope, the better the resolution. The first phase of the survey only processed data from the central stations located in the Netherlands, but UK astronomers are now re-processing the data with all of the international stations to provide resolution twenty times better.

    The team aims to make sensitive high-resolution images of the whole northern sky, which will reveal 15 million radio sources in total.

    Dr Leah Morabito, from Oxford Astrophysics added: ‘This extra phase of the survey will be truly unique in the history of radio astronomy, and who knows what mysteries we’ll uncover?’

    See the full article here.


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    Please help promote STEM in your local schools.

    Stem Education Coalition

    U Oxford campus

    Oxford is a collegiate university, consisting of the central University and colleges. The central University is composed of academic departments and research centres, administrative departments, libraries and museums. The 38 colleges are self-governing and financially independent institutions, which are related to the central University in a federal system. There are also six permanent private halls, which were founded by different Christian denominations and which still retain their Christian character.

    The different roles of the colleges and the University have evolved over time.

     
  • richardmitnick 11:21 am on February 19, 2019 Permalink | Reply
    Tags: 24 radio telescopes from the Low Frequency Array (LOFAR), , Astrophysics, , , , , University of Helsinki   

    From University of Helsinki via COSMOS: “Observations reveal new ‘shape’ for coronal mass ejections” 

    From University of Helsinki

    via

    Cosmos Magazine bloc

    COSMOS Magazine

    19 February 2019
    Phil Dooley

    Radiation signatures produced by giant solar storms more complex than previously thought.

    1
    An artist’s impression of a coronal mass ejection. LV4260/Getty Images

    Astronomers using one of the most sensitive arrays of radio telescopes in the world have caught a huge storm erupting on the sun and observed material flung from it at more than 3000 kilometres a second, a massive shockwave and phenomena known as herringbones.

    In the journal Nature Astronomy, Diana Morosan from the University of Helsinki in Finland and her colleagues report detailed observations of the huge storm, a magnetic eruption known as a coronal mass ejection (CME).

    Unlike the herringbones a biologist might find while dissecting, well, a herring, the team found a data-based version while dissecting the radio waves emitted during the violent event.

    The shape of the fish skeleton emerged when they plotted the frequencies of radio waves as the CME evolved. The spine is a band of emission at a constant frequency, while the vertical offshoot “bones” on either side were sudden short bursts of radiation at a much wider range of frequencies.

    Herringbones have been found in the sun’s radio-wave entrails before, but this is the first time that such a sensitive array of radio telescopes has recorded them. The detailed data enabled Morosan and colleagues for the first time to pin down the origin of the radiation bursts.

    To their surprise, the bones were being created in three different locations, on the sides of the CME.

    “I was very excited when I first saw the results, I didn’t know what to make of them,” Morosan says.

    As the CME erupted, the astronomers were already monitoring the sun, using 24 radio telescopes from the Low Frequency Array (LOFAR) distributed around an area of about 320 hectares near the village of Exloo in The Netherlands.

    ASTRON LOFAR Radio Antenna Bank, Netherlands

    SKA LOFAR core (“superterp”) near Exloo, Netherlands

    “We had seen this really complicated active region – really big ugly sunspots, that had already produced three X-class flares, so we thought we should point LOFAR at it and see if it produces any other eruptions,” explains Morosan.

    A last minute request to the LOFAR director was rewarded with an eight-hour slot on the following Sunday, during which the active region erupted again, emitting X-rays so intense that it was classified as an X-class flare, the most extreme category.

    Flares are caused by turbulence in the plasma that makes up the sun. Plasma is gas that is so hot that the electrons begin to be stripped from the atoms, forming a mixture of charged particles. As it swirls around in the sun the charged particles create magnetic fields. When the turbulence rises the magnetic field lines can get contorted and unstable, a little like a tightly coiled and tangled spring.

    Sometimes the tangled magnetic field suddenly rearranges itself in a violent event called magnetic reconnection, a bit like a coiled spring breaking and thus releasing a lot of trapped energy. It is this energy that powers the flare and propels the plasma out into space to form the CME.

    “The CME is still connected to the solar atmosphere via the magnetic field, so it looks like a giant bubble expanding out,” Morosan says.

    The extreme energy in the CME – the second largest during the sun’s most recent 11-year cycle – accelerated matter away from the sun’s surface to over 3000 kilometres per second, or 1% of the speed of light.

    Because it was so fast the CME formed a shockwave as it travelled through the heliosphere – the atmosphere around the sun. Similar to the sonic boom created by a supersonic aircraft, the shockwave accelerated electrons to extreme speeds and caused them to emit radio waves that Morosan and her colleagues recorded.

    The exact frequency of the radio waves emitted by the electrons depends on the density of their environment. Close to the sun the photosphere density is higher, which creates higher frequency radio waves. The further the electrons are from the sun the lower the frequency of the radio emission.

    So the shape of the herringbones as a plot of frequencies shows where the accelerated electrons are in the sun’s atmosphere.

    The spine represents a constant frequency emission originating from electrons trapped in the shockwave. These escape in bursts from the shock and get funneled along the magnetic field lines on the surface of the CME bubble.

    Some bursts of electrons are funneled back towards the sun. These are the herringbone offshoots to higher frequency, while the ones that get funneled the other way, out into space, create offshoots to lower frequency.

    The sensitivity of the array of radio telescopes allowed the team to clearly identify three sources of herringbone radiation, all of them on the flanks of the CME, not at the front of it, as had been proposed.

    However, the success of the observation was cut short because the timeslot on the LOFAR array came to its end, while the CME was still in full swing.

    “We don’t know what happened after the flare peaked,” Morosan notes. “So we were lucky, and unlucky!”

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    U Helsinki main building

    University of Helsinki, Viikki campus focusing on biological sciences

    The University of Helsinki (Finnish: Helsingin yliopisto, Swedish: Helsingfors universitet, Latin: Universitas Helsingiensis, abbreviated UH) is a university located in Helsinki, Finland since 1829, but was founded in the city of Turku (in Swedish Åbo) in 1640 as the Royal Academy of Åbo, at that time part of the Swedish Empire. It is the oldest and largest university in Finland with the widest range of disciplines available. Around 36,500 students are currently enrolled in the degree programs of the university spread across 11 faculties and 11 research institutes.

    As of 1 August 2005, the university complies with the harmonized structure of the Europe-wide Bologna Process and offers Bachelor, Master, Licenciate, and Doctoral degrees. Admission to degree programmes is usually determined by entrance examinations, in the case of bachelor’s degrees, and by prior degree results, in the case of master and postgraduate degrees. Entrance is particularly selective (circa 15% of the yearly applicants are admitted). It has been ranked a top 100 university in the world according to the 2016 ARWU, QS and THE rankings.

    The university is bilingual, with teaching by law provided both in Finnish and Swedish. Since Swedish, albeit an official language of Finland, is a minority language, Finnish is by far the dominating language at the university. Teaching in English is extensive throughout the university at Master, Licentiate, and Doctoral levels, making it a de facto third language of instruction.

    Remaining true to its traditionally strong Humboldtian ethos, the University of Helsinki places heavy emphasis on high-quality teaching and research of a top international standard. It is a member of various prominent international university networks, such as Europaeum, UNICA, the Utrecht Network, and is a founding member of the League of European Research Universities.

     
  • richardmitnick 9:47 am on February 19, 2019 Permalink | Reply
    Tags: "Astronomers Have Detected a Previously Unnoticed 'River of Stars' Flowing Past Earth", , Astrophysics, , , ESA/GAIA DR 2, ,   

    From University of Vienna via Science Alert: “Astronomers Have Detected a Previously Unnoticed ‘River of Stars’ Flowing Past Earth” 

    From University of Vienna

    via

    ScienceAlert

    Science Alert

    1
    (MoazAqeelChishti/CC BY-SA 4.0)

    19 FEB 2019
    MICHELLE STARR

    If you live in the Southern Hemisphere, next time you get the opportunity, go outside and look at the night sky. Most of that celestial plain is covered in a star cluster that’s been torn apart by galactic tidal forces, and is now flowing past us as a giant river of over 4,000 stars.

    Although it may be in plain sight, it’s only just been discovered, revealed by the Gaia data that facilitated the most accurate 3D-map of the galaxy yet.

    ESA/GAIA satellite

    ESA GAIA Release 2 map

    What makes this stellar stream exciting is its proximity to Earth. It’s just 100 parsecs (326 light-years) away, offering an unprecedented opportunity to peer into the dynamics of a disrupted cluster.

    “Identifying nearby disc streams is like looking for the proverbial needle in a haystack. Astronomers have been looking at, and through, this new stream for a long time, as it covers most of the night sky, but only now realise it is there, and it is huge, and shockingly close to the Sun,” said astrophysicist João Alves of the University of Vienna.

    “Finding things close to home is very useful, it means they are not too faint nor too blurred for further detailed exploration, as astronomers dream.”

    Stars tend to form in clusters in stellar nurseries, but they don’t usually stay clustered for long – maybe up to a few hundred thousand years.

    Stellar Nursery NASA/Spitzer Image credit NASA/JPL-Caltech W. Reach (SSC-Caltech)

    It takes a lot of mass to build up enough gravity to hold a cluster together – even small galaxies orbiting the Milky Way can be torn apart by its tidal forces and end up stretched out into long rivers of stars orbiting the galactic core.

    These can be hard to see, as Alves said, because we need quite a bit of information to be able to link the stars to each other. But this is what Gaia provided. Not only has it given accurate locations in 3D space for stars, it has given us their velocities, and excited astronomers have been using this data to identify stellar streams.

    So when University of Vienna astronomers noticed a group of stars moving together, they took a closer look. They found the group bore the signatures of a stellar cluster that had been torn apart, and was now a stellar stream.

    The river of stars in the southern sky. ESA/GAIA (Gaia DR2 skymap)

    Due to Gaia sensitivity limitations, they were only able to analyse 200 stars in detail, but based on the interactions between the stars, the team extrapolated that the stream should contain at least 4,000 stars.

    This star river is sizeable, about 200 parsecs (652 light-years) wide and 400 parsecs (1,305 light-years) long. These dimensions also help estimate its age.

    The stream, the team argue, is not dissimilar to the open cluster the Hyades. At around 625 million years old, the Hyades is showing evidence of a tidal tail; it’s in the early stages of being disrupted.

    Hence, the researchers think this stream is older than the Hyades. Based on this comparison, and a set of stellar isochrone data (used to calculate the age of stars), the team has put the age of the stream at about 1 billion years.

    That means it’s completed around four full orbits of the Milky Way (the Sun takes about 230 million years to orbit the galactic core), which is sufficient time for it have stretched out into its attenuated shape.

    “As soon as we investigated this particular group of stars in more detail, we knew that we had found what we were looking for: A coeval, stream-like structure, stretching for hundreds of parsecs across a third of the entire sky,” said astronomer Verena Fürnkranz [Astronomy and Astrophysics].

    Most Milky Way stellar streams identified to date are actually orbiting outside the galactic disc, and are much larger – but this stream’s location inside the disc could make it a valuable tool. For example, it could be used to help constrain the Milky Way’s mass distribution.

    It could also help shed light on how galaxies get stars, and test the Milky Way’s gravitational field, the researchers said.

    With the help of the Gaia data, they plan to look for more such streams in the night sky, hiding in plain sight.

    See the full article here .

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

    Please help promote STEM in your local schools.

    Stem Education Coalition

    The University of Vienna (German: Universität Wien) is a public university located in Vienna, Austria. It was founded by Duke Rudolph IV in 1365 and is one of the oldest universities in the German-speaking world. With its long and rich history, the University of Vienna has developed into one of the largest universities in Europe, and also one of the most renowned, especially in the Humanities. It is associated with 15 Nobel prize winners and has been the academic home to a large number of scholars of historical as well as of academic importance.

     
  • richardmitnick 4:01 pm on February 18, 2019 Permalink | Reply
    Tags: A new technique dubbed STeVE for “starting TeV events, A second technique called LESE for low-energy starting events, , Astrophysics, , Both of these techniques introduce a new online event selection filter that selects starting events based on an initial fast reconstruction, , , Gamma-ray emission, However gamma rays can also be produced in environments where neutrino emission would be disfavored, , Searches combining both techniques result in an effective area comparable to ANTARES which thanks to its location in the Mediterranean Sea has a priori a better neutrino view of our galaxy, STeVE and LESE where tested with 3 and 4 years of IceCube data respectively, The gamma-ray galactic sky shows a large concentration of sources in the Southern Hemisphere, The highest energy gamma rays could be produced in the same mechanisms that produce the highest energy neutrinos,   

    From U Wisconsin IceCube Collaboration: “Improving searches for galactic sources of high-energy neutrinos” 

    U Wisconsin ICECUBE neutrino detector at the South Pole

    18 Feb 2019
    Sílvia Bravo

    The search for sources of high-energy neutrinos and cosmic rays has revealed neutrinos from distant galaxies and from all over the sky traveling through the Antarctic ice. Closer sources, though, those that could produce neutrino emission in the Milky Way, have been more elusive.

    In IceCube, the signature of sources such as galactic supernova remnants peaks at low energies, well below 100 TeV, where the large background of atmospheric muons is difficult to filter out. The bulk of galactic neutrino emission is expected in the southern sky, where the Earth cannot serve as a natural filter to remove the million-to-one muon-neutrino signal. In a recent paper by the IceCube Collaboration, two new techniques improve searches at energies from 100 TeV down to 100 GeV. When tested with a few years of IceCube data, these new selections improve the sensitivity and discovery potential, allowing for the first time the search for galactic point-like sources using track events created by muon neutrinos that in many cases are indistinguishable from atmospheric muon tracks. These results have just been submitted to the journal Astroparticle Physics.

    1
    The differential discovery potential at −60° declination for LESE (light blue), STeVE (dark blue), the combined selection (LESE +STeVE) (red), a cascade point-source search (gray), a starting tracks search targeting higher energies (MESE) (gray dashed), throughgoing (light gray dashed), all with the IceCube detector, and of the ANTARES point-like source search (black). In this plot, all results are calculated for an equal three-year exposure. Image: IceCube Collaboration

    Scientists have speculated that at high energies neutrino emission should be associated with gamma-ray emission, since the highest energy gamma rays could be produced in the same mechanisms that produce the highest energy neutrinos. However, gamma rays can also be produced in environments where neutrino emission would be disfavored.

    The gamma-ray galactic sky shows a large concentration of sources in the Southern Hemisphere, where both the galactic center and the majority of the galactic plane are seen from Earth. This is, thus, a region worth exploring with IceCube to look for potential neutrino emission from the same sources that produce the gamma rays.

    However, the most successful searches for high-energy neutrinos select particle interactions that start in the detector—both cascade- and track-like events—or track-like events that come from the northern sky. Track-like events are those that provide a good pointing resolution, which on average is well below 1 degree.

    In previous searches for astrophysical neutrinos using events with the interaction vertex within the detector, a fairly high energy cut was also applied to obtain an efficient selection. The concern is that the majority of galactic neutrino emission could happen at lower energies and, thus, might be removed with this cut. To lower this energy threshold and still preserve a good pointing resolution in the southern sky, researchers have looked closer at track events in IceCube.

    In a new technique dubbed STeVE, for “starting TeV events,” the selection focuses on neutrino events between 10 and 100 TeV and uses techniques developed in a previous IceCube analysis (link to MESE news 414) to remove the background of multiple parallel atmospheric muon events, which has proved to be a resistant background at low energies. In addition, this event selection strategy exploits the difference in the observed photon pattern of bundles of low-energy atmospheric muons compared to individual high-energy muons.

    In a second technique, called LESE, for low-energy starting events, the selection was optimized for neutrinos below 10 TeV. At low energies and due to the small granularity of the IceCube detector, with strings of sensors deployed at horizontal distances of 125 meters, it’s easier for muon tracks to enter the detector without significant energy deposition detected by the outer layers of sensors, which mimics a muon neutrino interacting within the detector volume. LESE aims at selecting track-like events with energies as low as 100 GeV, leveraging the experience gained with veto-based selection techniques in searches for dark matter.

    Both of these techniques introduce a new online event selection filter that selects starting events based on an initial fast reconstruction. This new filter is the first to accept starting events from the entire southern sky while maintaining as large as possible active detector volume.

    STeVE and LESE where tested with 3 and 4 years of IceCube data, respectively, in a search for sources of astrophysical neutrinos anywhere in the southern sky and for neutrino emission from the direction of 96 known gamma-ray sources. No significant excess of neutrino emission was found, but the techniques have proven to be sensitive to strong galactic sources of low-energy astrophysical neutrinos.

    “Studying starting events from the southern sky at these energies poses many new challenges,” explains Rickard Ström, a main analyzer who worked on this study as a PhD candidate at Uppsala University. “We leveraged expertise from previous searches for point sources and exotic signatures such as dark matter. This was the first time IceCube was able to study point sources in the southern sky at these energies and using tracks with degree precision,” adds Ström.

    Searches combining both techniques result in an effective area comparable to ANTARES, which thanks to its location in the Mediterranean Sea has a priori a better neutrino view of our galaxy. STeVE and LESE selections reduce the muon background to a few thousand events per year and significantly improve IceCube’s sensitive and discovery potential of point-like sources in the southern sky with neutrinos with energies below 100 TeV.

    From From U Wisconsin IceCube Collaboration

    See the full article here .

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    Please help promote STEM in your local schools.

    Stem Education Coalition
    IceCube is a particle detector at the South Pole that records the interactions of a nearly massless sub-atomic particle called the neutrino. IceCube searches for neutrinos from the most violent astrophysical sources: events like exploding stars, gamma ray bursts, and cataclysmic phenomena involving black holes and neutron stars. The IceCube telescope is a powerful tool to search for dark matter, and could reveal the new physical processes associated with the enigmatic origin of the highest energy particles in nature. In addition, exploring the background of neutrinos produced in the atmosphere, IceCube studies the neutrinos themselves; their energies far exceed those produced by accelerator beams. IceCube is the world’s largest neutrino detector, encompassing a cubic kilometer of ice.

    IceCube employs more than 5000 detectors lowered on 86 strings into almost 100 holes in the Antarctic ice NSF B. Gudbjartsson, IceCube Collaboration

    Lunar Icecube

    IceCube DeepCore annotated

    IceCube PINGU annotated


    DM-Ice II at IceCube annotated

     
  • richardmitnick 3:29 pm on February 18, 2019 Permalink | Reply
    Tags: , Astrophysics, , , , Video "ESOcast 194: Cutting Edge of Contemporary Astronomy"   

    From European Southern Observatory: Video “ESOcast 194: Cutting Edge of Contemporary Astronomy” 

    ESO 50 Large

    From European Southern Observatory

    ESOcast 194: Cutting Edge of Contemporary Astronomy – Video

    ESO’s observatories operate a suite of the most advanced ground-based astronomical telescopes in the world, providing researchers with state-of-the-art facilities to study the Universe. Observing time on the telescopes is highly sought-after due to the remarkable detail in which they can capture the sky.

    Every year, ESO receives thousands of observing proposals from researchers across the globe – up to ten times more hours of observations than are actually available. ESO therefore has to decide which cutting-edge astronomical questions should be awarded valuable telescope time .

    In this ESOcast, six of the astronomers who help to make these decisions tell us about the hottest topics in contemporary astronomy. Covering topics ranging from dark matter to exoplanets, these astronomers make the case for why these cutting-edge fields deserve time at ESO’s telescopes.

    You can subscribe to the ESOcasts on iTunes or receive future episodes on YouTube.

    Many other ESOcast episodes are also available.

    See the full article here .


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    Please help promote STEM in your local schools.


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    Visit ESO in Social Media-

    Facebook

    Twitter

    YouTube

    ESO Bloc Icon

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

    ESO La Silla HELIOS (HARPS Experiment for Light Integrated Over the Sun)

    ESO/HARPS at La Silla

    ESO 3.6m telescope & HARPS at Cerro LaSilla, Chile, 600 km north of Santiago de Chile at an altitude of 2400 metres.

    ESO 2.2 meter telescope at La Silla, 600 km north of Santiago de Chile at an altitude of 2400 metres.

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

    ESO VLT Platform at Cerro Paranal elevation 2,635 m (8,645 ft)


    ESO VLT 4 lasers on Yepun

    Glistening against the awesome backdrop of the night sky above ESO_s Paranal Observatory, four laser beams project out into the darkness from Unit Telescope 4 UT4 of the VLT.

    ESO/NTT at Cerro La Silla, Chile, at an altitude of 2400 metres



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

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

    ESO/E-ELT,to be on top of Cerro Armazones in the Atacama Desert of northern Chile. located at the summit of the mountain at an altitude of 3,060 metres (10,040 ft).

    ESO/APEX high on the Chajnantor plateau in Chile’s Atacama region, at an altitude of over 4,800 m (15,700 ft)

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

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

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

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

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

    ESO ExTrA telescopes at Cerro LaSilla at an altitude of 2400 metres

     
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