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  • richardmitnick 2:32 pm on August 3, 2017 Permalink | Reply
    Tags: , , , , Magnetar, SN 2017egm,   

    From CfA: “Astronomers Discover “Heavy Metal” Supernova Rocking Out” 

    Harvard Smithsonian Center for Astrophysics


    Center For Astrophysics

    July 31, 2017
    Megan Watzke
    Harvard-Smithsonian Center for Astrophysics
    +1 617-496-7998
    mwatzke@cfa.harvard.edu

    Peter Edmonds
    Harvard-Smithsonian Center for Astrophysics
    +1 617-571-7279
    pedmonds@cfa.harvard.edu

    1

    Many rock stars don’t like to play by the rules, and a cosmic one is no exception. A team of astronomers has discovered that an extraordinarily bright supernova occurred in a surprising location. This “heavy metal” supernova discovery challenges current ideas of how and where such super-charged supernovas occur.

    Supernovas are some of the most energetic events in the Universe. When a massive star runs out of fuel, it can collapse onto itself and create a spectacular explosion that briefly outshines an entire galaxy, dispersing vital elements into space.

    In the past decade, astronomers have discovered about fifty supernovas, out of the thousands known, that are particularly powerful. These explosions are up to 100 times brighter than other supernovas caused by the collapse of a massive star.

    Following the recent discovery of one of these “superluminous supernovas”, a team of astronomers led by Matt Nicholl from the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass., has uncovered vital clues about where some of these extraordinary objects come from.

    Cambridge University’s Gaia Science Alerts team discovered this supernova, dubbed SN 2017egm, on May 23, 2017 with the European Space Agency’s Gaia satellite.

    ESA/GAIA satellite


    Nordic Optical telescope, at Roque de los Muchachos Observatory, La Palma in the Canary Islands, Spain


    A team led by Subo Dong of the Kavli Institute for Astronomy and Astrophysics at Peking University used the Nordic Optical Telescope to identify it as a superluminous supernova.

    SN 2017egm is located in a spiral galaxy about 420 million light years from Earth, making it about three times closer than any other superluminous supernova previously seen. Dong realized that the galaxy was very surprising, as virtually all known superluminous supernovas have been found in dwarf galaxies that are much smaller than spiral galaxies like the Milky Way.

    Building on this discovery, the CfA team found that SN 2017egm’s host galaxy has a high concentration of elements heavier than hydrogen and helium, which astronomers call “metals”. This is the first clear evidence for a metal-rich birthplace for a superluminous supernova. The dwarf galaxies that usually host superluminous supernovas are known to have a low metal content, which was thought to be an essential ingredient for making these explosions.

    “Superluminous supernovas were already the rock stars of the supernova world,” said Nicholl. “We now know that some of them like heavy metal, so to speak, and explode in galaxies like our own Milky Way.”

    “If one of these went off in our own Galaxy, it would be much brighter than any supernova in recorded human history and would be as bright as the full Moon,” said co-author Edo Berger, also of the CfA. “However, they’re so rare that we probably have to wait several million years to see one.”

    The CfA researchers also found more clues about the nature of SN 2017egm. In particular, their new study supports the idea that a rapidly spinning, highly magnetized neutron star, called a magnetar, is likely the engine that drives the incredible amount of light generated by these supernovas.

    While the brightness of SN 2017egm and the properties of the magnetar that powers it overlap with those of other superluminous supernovas, the amount of mass ejected by SN 2017egm may be lower than the average event. This difference may indicate that the massive star that led to SN 2017egm lost more mass than most superluminous supernova progenitors before exploding. The spin rate of the magnetar may also be slower than average.

    These results show that the amount of metals has at most only a small effect on the properties of a superluminous supernova and the engine driving it. However, the metal-rich variety occurs at only about 10% of the rate of the metal-poor ones. Similar results have been found for bursts of gamma rays associated with the explosion of massive stars. This suggests a close association between these two types of objects.

    From July 4th, 2017 until September 16th, 2017 the supernova is not observable because it is too close to the Sun. After that, detailed studies should be possible for at least a few more years.

    “This should break all records for how long a superluminous supernova can be followed”, said co-author Raffaella Margutti of Northwestern University in Evanston, Illinois. “I’m excited to see what other surprises this object has in store for us.”

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    The CfA team observed SN 2017egm on June 18th with the 60-inch telescope at the Smithsonian Astrophysical Observatory’s Fred Lawrence Whipple Observatory in Arizona.

    A paper by Matt Nicholl describing these results was recently accepted for publication in The Astrophysical Journal Letters, and is available online. In addition to Berger and Margutti, the co-authors of the paper are Peter Blanchard, James Guillochon, and Joel Leja, all of the CfA, and Ryan Chornock of Ohio University in Athens, Ohio.

    See the full article here .

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    The Center for Astrophysics combines the resources and research facilities of the Harvard College Observatory and the Smithsonian Astrophysical Observatory under a single director to pursue studies of those basic physical processes that determine the nature and evolution of the universe. The Smithsonian Astrophysical Observatory (SAO) is a bureau of the Smithsonian Institution, founded in 1890. The Harvard College Observatory (HCO), founded in 1839, is a research institution of the Faculty of Arts and Sciences, Harvard University, and provides facilities and substantial other support for teaching activities of the Department of Astronomy.

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  • richardmitnick 10:15 am on June 22, 2016 Permalink | Reply
    Tags: , , , Magnetar, , ,   

    From Goddard: “Astronomers Find the First ‘Wind Nebula’ Around a Magnetar” 

    NASA Goddard Banner
    NASA Goddard Space Flight Center

    June 21, 2016
    Francis Reddy
    francis.j.reddy@nasa.gov
    NASA’s Goddard Space Flight Center, Greenbelt, Maryland

    Astronomers have discovered a vast cloud of high-energy particles called a wind nebula around a rare ultra-magnetic neutron star, or magnetar, for the first time. The find offers a unique window into the properties, environment and outburst history of magnetars, which are the strongest magnets in the universe.

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    This X-ray image shows extended emission around a source known as Swift J1834.9-0846, a rare ultra-magnetic neutron star called a magnetar. The glow arises from a cloud of fast-moving particles produced by the neutron star and corralled around it. Color indicates X-ray energies, with 2,000-3,000 electron volts (eV) in red, 3,000-4,500 eV in green, and 5,000 to 10,000 eV in blue. The image combines observations by the European Space Agency’s XMM-Newton spacecraft taken on March 16 and Oct. 16, 2014. Credits: ESA/XMM-Newton/Younes et al. 2016

    ESA/XMM Newton
    ESA/XMM Newton

    A neutron star is the crushed core of a massive star that ran out of fuel, collapsed under its own weight, and exploded as a supernova. Each one compresses the equivalent mass of half a million Earths into a ball just 12 miles (20 kilometers) across, or about the length of New York’s Manhattan Island. Neutron stars are most commonly found as pulsars, which produce radio, visible light, X-rays and gamma rays at various locations in their surrounding magnetic fields. When a pulsar spins these regions in our direction, astronomers detect pulses of emission, hence the name.

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    This illustration compares the size of a neutron star to Manhattan Island in New York, which is about 13 miles long. A neutron star is the crushed core left behind when a massive star explodes as a supernova and is the densest object astronomers can directly observe. Credits: NASA’s Goddard Space Flight Center

    Typical pulsar magnetic fields can be 100 billion to 10 trillion times stronger than Earth’s. Magnetar fields reach strengths a thousand times stronger still, and scientists don’t know the details of how they are created. Of about 2,600 neutron stars known, to date only 29 are classified as magnetars.

    The newfound nebula surrounds a magnetar known as Swift J1834.9-0846 — J1834.9 for short — which was discovered by NASA’s Swift satellite on Aug. 7, 2011, during a brief X-ray outburst.

    NASA/SWIFT Telescope
    NASA/SWIFT Telescope

    Astronomers suspect the object is associated with the W41 supernova remnant, located about 13,000 light-years away in the constellation Scutum toward the central part of our galaxy.

    “Right now, we don’t know how J1834.9 developed and continues to maintain a wind nebula, which until now was a structure only seen around young pulsars,” said lead researcher George Younes, a postdoctoral researcher at George Washington University in Washington. “If the process here is similar, then about 10 percent of the magnetar’s rotational energy loss is powering the nebula’s glow, which would be the highest efficiency ever measured in such a system.”

    A month after the Swift discovery, a team led by Younes took another look at J1834.9 using the European Space Agency’s (ESA) XMM-Newton X-ray observatory, which revealed an unusual lopsided glow about 15 light-years across centered on the magnetar. New XMM-Newton observations in March and October 2014, coupled with archival data from XMM-Newton and Swift, confirm this extended glow as the first wind nebula ever identified around a magnetar. A paper describing the analysis will be published by The Astrophysical Journal.

    “For me the most interesting question is, why is this the only magnetar with a nebula? Once we know the answer, we might be able to understand what makes a magnetar and what makes an ordinary pulsar,” said co-author Chryssa Kouveliotou, a professor in the Department of Physics at George Washington University’s Columbian College of Arts and Sciences.

    The most famous wind nebula, powered by a pulsar less than a thousand years old, lies at the heart of the Crab Nebula supernova remnant in the constellation Taurus. Young pulsars like this one rotate rapidly, often dozens of times a second. The pulsar’s fast rotation and strong magnetic field work together to accelerate electrons and other particles to very high energies. This creates an outflow astronomers call a pulsar wind that serves as the source of particles making up in a wind nebula.

    Supernova remnant Crab nebula. NASA/ESA Hubble
    The best-known wind nebula is the Crab Nebula, located about 6,500 light-years away in the constellation Taurus. At the center is a rapidly spinning neutron star that accelerates charged particles like electrons to nearly the speed of light. As they whirl around magnetic field lines, the particles emit a bluish glow. This image is a composite of Hubble observations taken in late 1999 and early 2000. The Crab Nebula spans about 11 light-years. Credits: NASA, ESA, J. Hester and A. Loll (Arizona State University)

    “Making a wind nebula requires large particle fluxes, as well as some way to bottle up the outflow so it doesn’t just stream into space,” said co-author Alice Harding, an astrophysicist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “We think the expanding shell of the supernova remnant serves as the bottle, confining the outflow for a few thousand years. When the shell has expanded enough, it becomes too weak to hold back the particles, which then leak out and the nebula fades away.” This naturally explains why wind nebulae are not found among older pulsars, even those driving strong outflows.

    A pulsar taps into its rotational energy to produce light and accelerate its pulsar wind. By contrast, a magnetar outburst is powered by energy stored in the super-strong magnetic field. When the field suddenly reconfigures to a lower-energy state, this energy is suddenly released in an outburst of X-rays and gamma rays. So while magnetars may not produce the steady breeze of a typical pulsar wind, during outbursts they are capable of generating brief gales of accelerated particles.

    “The nebula around J1834.9 stores the magnetar’s energetic outflows over its whole active history, starting many thousands of years ago,” said team member Jonathan Granot, an associate professor in the Department of Natural Sciences at the Open University in Ra’anana, Israel. “It represents a unique opportunity to study the magnetar’s historical activity, opening a whole new playground for theorists like me.”

    ESA’s XMM-Newton satellite was launched on Dec. 10, 1999, from Kourou, French Guiana, and continues to make observations. NASA funded elements of the XMM-Newton instrument package and provides the NASA Guest Observer Facility at Goddard, which supports use of the observatory by U.S. astronomers.

    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.

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  • richardmitnick 7:57 am on March 26, 2016 Permalink | Reply
    Tags: , , , Magnetar,   

    From Astronomy Now: “Magnetar could have boosted explosion of extremely bright supernova” 

    Astronomy Now bloc

    Astronomy Now

    25 March 2016
    No writer credit found

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    Artist’s impression of a magnetar boosting a super-luminous supernova and gamma-ray burst. Image credit: Kavli IPMU.

    Calculations by scientists have found highly magnetised, rapidly spinning neutron stars called magnetars could explain the energy source behind two extremely unusual stellar explosions.

    Stellar explosions known as supernovae usually shine a billion times brighter than the Sun. Super-luminous supernovae [hypernovae] (SLSNe) are a relatively new and rare class of stellar explosions, 10 to 100 times brighter than normal supernovae. But the energy source of their super-luminosity, and explosion mechanisms are a mystery and remain controversial amongst scientists.

    A group of researchers led by Melina Bersten, an Instituto de Astrofisica de La Plata researcher and affiliate member of Kavli IPMU, and including Kavli IPMU Principal Investigator Ken’ichi Nomoto, tested a model that suggests that the energy to power the luminosity of two recently discovered SLSNe, SN 2011kl and ASASSN-15lh, is mainly due to the rotational energy lost by a newly born magnetar.

    “These supernovae can be found in very distant universe, thus possibly informing us the properties of the first stars of the universe,” said Nomoto.

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    The yellow-orange host galaxy (left) before the supernova, and afterwards (right) when the ASASSN-15lh supernova’s blue light outshines its host galaxy. Image credit: The Dark Energy Survey / B. Shappee / ASAS-SN team.

    Dark Energy Icon
    Dark Energy Camera. Built at FNAL
    NOAO/CTIO Victor M Blanco 4m Telescope
    Dark Energy Survey, Dark Energy Camera. Built at FNAL, NOAO/CTIO Victor M Blanco 4m Telescope which houses the DECam

    Interestingly, both explosions were found to be extreme cases of SLSNe. First, SN 2011kl was discovered in 2011 and is the first supernovae to have an ultra long gamma-ray burst that lasted several hours, whereas typical long-duration gamma-ray bursts fade in a matter of minutes. The second, ASASSN-15lh, was discovered in 2015 and is possibly the most luminous and powerful explosion ever seen, more than 500 times brighter than normal supernovae. For more than a month its luminosity was 20 times brighter than the whole Milky Way galaxy.

    The team performed numerical hydrodynamical calculations to explore the magnetar hypothesis, and found both SLSNe could be understood in the framework of magnetar-powered supernovae. In particular, for ASASSN-15lh, they were able to find a magnetar source with physically allowed properties of magnetic field strength and rotation period. The solution avoided the prohibited realm of neutron star spins that would cause the object to breakup due to centrifugal forces.

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    Light curves of ASASSN-15lh and SN 2011kl compared with normal supernovae SN 1999em and SN 1987A. Image credit: Bersten et al.

    “These two extreme super-luminous supernovae put to the test our knowledge of stellar explosions,” said Bersten.

    To confirm the team’s calculations, further observations would need to be carried out when the material ejected by the supernova is expected to become thin. The most powerful telescopes, including the NASA/ESA Hubble Space Telescope, will be required for this purpose. If correct, these observations will allow scientists to probe the inner part of an exploding object, and provide new insight on its origin, and evolution of stars in the Universe.

    NASA/ESA Hubble Telescope
    NASA/ESA Hubble Telescope

    The group’s paper was recently published in The Astrophysical Journal Letters.

    Science team:
    Melina C. Bersten, Omar G. Benvenuto, Mariana Orellana, and Ken’ichi Nomoto

    See the full article here .

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  • richardmitnick 8:49 pm on January 11, 2016 Permalink | Reply
    Tags: , , Magnetar, , SCIENCELINE, Starquake   

    From NYU SCIENCELINE: “Starquake!” 

    NYU BLOC

    New York University

    NYU SCIENCELINE bloc
    SCIENCELINE

    Massive radiation pulses occasionally rock the Earth – and they’re still a mystery

    Temp 1

    January 11, 2016
    Dyani Sabin

    On Dec. 27, 2004, for a tenth of second, a blast of energy knocked satellites offline, disrupted submarine and radio transmissions, and shifted the magnetic field of the Earth. Within minutes, everything was back to normal, but astrophysicists all over the world were left staring at their instruments asking, “what was that?”

    Every researcher with an instrument pointed at the sky was bombarded with emails and phone calls, despite the holiday season. David Palmer, an astrophysicist at Los Alamos National Laboratory, got an email asking if the pulse detection software he had designed for the SWIFT satellite had gotten any weird readings that day.

    NASA SWIFT Telescope
    NASA/SWIFT

    The satellite had only been in space for slightly over a month, but Palmer logged in anyway to check. Although the satellite was looking the wrong way, gamma rays, which are powerful bursts of energy, had gone straight through it — more gamma rays than are emitted from the Sun in the course of 150,000 years.

    “I thought, it was probably a giant burst [from a star], or there was something going wrong in the instrument,” Palmer said. But he and researchers all over the world concluded that the satellite was fine — and that the mass of radiation that hit the earth came from something called a starquake.

    A starquake is vaguely similar to an earthquake but occurs on a magnetar, a mysterious type of star that is extremely dense and magnetic.

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    Artist’s conception of a magnetar, with magnetic field lines.

    To date, scientists have only identified 23 magnetars, and recorded three starquakes: one each in 1979, 1998 and 2004. Researchers cannot predict starquakes, so while they wait for one they are working on tools to better understand these events and the stars that create them. Two of those new tools are almost ready: a new technique to look at the magnetic interior of stars, and NASA’s Neutron Star Interior Composition Explorer mission, or NICER, due to launch in late 2016.

    NASA NICER
    NASA/NICER

    Only about 15 miles across, magnetars are likely the cores that remain after the deaths of supermassive stars. They have the strongest magnetic fields of any object in the universe by several orders of magnitude, says Anna Watts, an astrophysicist at the University of Amsterdam who studies neutron stars and black holes. In fact, a magnetar’s magnetic field is about two quadrillion times more powerful than the magnetic field of the Earth, and a thousand times stronger than a neutron star — the bright cores that remain after the death of a supernova. Conditions inside a magnetar are at a scale that cannot be replicated anywhere else, even at the largest particle physics lab in the world, she says. “CERN is never going to get to the energy and density we [see in these stars].”

    Deep inside the magnetar “everything just becomes a soup of neutrons and protons,” the basic building blocks of atoms, explains Tod Strohmayer, a NASA astrophysicist and co-investigator on the NICER mission. In fact, he says, a magnetar is so dense that it may be crushing these atomic components into a soup of their fundamental particles, called quarks. Structured like a cosmic M&M, the magnetar’s soupy core may be surrounded by a crust resembling superhot, dense, iron crystal. “A neutron star crust is the strongest material that we know of in the universe,” says Strohmayer — but it’s not quite strong enough to contain the phenomenal power of a bursting starquake.

    “We have no idea what the trigger process is for these things,” says Watts. The current theory suggests that, similarly to earthquakes, the crust rips as the magnetar’s powerful magnetic field moves. The shift pulls the inside of the star like a ball of rubber bands that eventually snap under the pressure. When the crust heats up and finally tears, a fireball of electrons, photons and plasma emerges as a bubble on the side of the star, researchers believe. A bright beam of radiation attaches the fiery bubble to the magnetar, and emits a giant burst of energy. As the bubble rotates around the star, it slowly shrinks back down its beam like the ball dropping on New Years Eve, eventually merging back into the core.

    Even though it originated 50,000 light years away, the giant pulse of energy from the 2004 starquake was enough to knock all research and commercial satellites offline, says Brian Gaensler, director of the Dunlap Institute of Astronomy and Astrophysics at the University of Toronto in Canada. Satellites are designed to withstand short bursts of radiation, like what happens during solar flares, and can typically reboot and go back online after the event is over. As the satellites rebooted, researchers were able to track the direction of the starquake by mapping when each satellite was knocked offline. Gaensler says that he suspects the blast also affected military satellites but that researchers were not supplied with that data.

    Some U.S. Navy’s stealthy communication equipment was briefly knocked out too, because the starquake temporarily altered the shape of the ionosphere, the outer edge of Earth’s atmosphere. As the pulses of energy hit the Earth, the powerful waves caused the ionosphere to expand and contract as each wave passed. The weird alteration knocked out low-frequency radio communications that rely on bouncing signals off the ionosphere, a technique used by Navy submarines, Gaensler says. Once the flare was over, transmission resumed as normal, but the magnetic field of the Earth remains slightly shifted, a constant reminder of the power contained in these dim stars.

    Magnetars are difficult for astronomers to see except during a starquake, but can be identified by their semi-regular pulsation of radiation. Researchers believe that what they see as pulses are actually hotspots of radiation on the magnetar’s surface. Like a lighthouse beam, the spinning of the star moves the hotspot in and out of view as the magnetar rotates. Scientists have been tracking these soft pulses of radiation since 1973, when U.S. satellites created to monitor nuclear testing by the Soviet Union picked up this background noise during the Cold War. Today, the pulses provide most of the data researchers have on magnetars.

    Charting the radiation pulses allows researchers to estimate the strength of a magnetar’s magnetic field — the more slowly the magnetar pulses, the stronger the field — as well as to estimate its composition and size. As telescopes get better, researchers are able to get more information on subtle shifts of the magnetar pulses. But the technique is limited by the fact that magnetars are relatively small and dim, so it’s hard to get sensitive data unless they’re flaring, says NASA’s Strohmayer. “You always want to build a bigger telescope.”

    Soon, Strohmayer may get the better data he’s pining for. In late 2016, NASA is set to send its NICER mission to the International Space Station. Its primary objective is to measure gamma radiation to better understand the size and mass of neutron stars, including magnetars. Strohmayer hopes that a starquake will occur while NICER is operational, but if it doesn’t, he is already scouting new technology to follow NICER. “Currently there’s nothing being built, although there are things on the drawing board,” he says.

    One of those tools could potentially come from a different field of astrophysics called astroseismology that uses the tiny changes in starlight to study the interior of a star. In October, two astroseismologists published the results of a technique they developed to detect the interior magnetic field of a star. Using minuscule variations in star brightness, Jim Fuller, a postdoctoral fellow in astrophysics at the California Institute of Technology, and Matteo Cantiello, an astrophysicist at the University of California at Santa Barbara, created a model that exposed the magnetic core hidden in a red giant star. They hope their work could one day be turned to other types of stars and maybe even help scientists understand how magnetars form when giant stars explode and die.

    “This will open up a whole new window into the interiors of stars,” says Fuller, though he adds that there is still a long way to go before the technique can be applied to the super giant stars that form magnetars or to magnetars themselves. But magnetar specialists like Amsterdam’s Watts are already excited to have recently learned that the core of a red giant is more magnetic than previously predicted. If this finding applies to other star types, it would explain how magnetars become so magnetic, she says.

    If all stars are more magnetic than we thought, “it’s not so hard to make a magnetar,” says Watts. Other possible explanations of magnetars’ super-magnetism involve rapidly spinning the dying super giant star. But the truth about magnetars and starquakes, she says, is that “we don’t know why they’re so odd.”

    See the full article here .

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    More than 175 years ago, Albert Gallatin, the distinguished statesman who served as secretary of the treasury under Presidents Thomas Jefferson and James Madison, declared his intention to establish “in this immense and fast-growing city … a system of rational and practical education fitting for all and graciously opened to all.” Founded in 1831, New York University is now one of the largest private universities in the United States. Of the more than 3,000 colleges and universities in America, New York University is one of only 60 member institutions of the distinguished Association of American Universities.

     
  • richardmitnick 10:42 am on September 6, 2015 Permalink | Reply
    Tags: , , Magnetar,   

    From NASA Goddard: “Cosmic Explosion Among the Brightest in Recorded History” 2005 But Worth Your Time 

    NASA Goddard Banner
    Goddard Space Flight Center

    [I do not know where this article was but here it is. I think that it was before I commenced this blog. It is well worth your time.]

    02.18.05
    Christopher Wanjek
    Goddard Space Flight Center

    Scientists have detected a flash of light from across the Galaxy so powerful that it bounced off the Moon and lit up the Earth’s upper atmosphere. The flash was brighter than anything ever detected from beyond our Solar System and lasted over a tenth of a second. NASA and European satellites and many radio telescopes detected the flash and its aftermath on December 27, 2004. Two science teams report about this event at a special press event today at NASA headquarters. A multitude of papers are planned for publication.

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    Image/animation above: Image 1: Artist conception of the December 27, 2004 gamma ray flare expanding from SGR 1806-20 and impacting Earth’s atmosphere. Credit: NASA

    The scientists said the light came from a “giant flare” on the surface of an exotic neutron star, called a magnetar. The apparent magnitude was brighter than a full moon and all historical star explosions. The light was brightest in the gamma-ray energy range, far more energetic than visible light or X-rays and invisible to our eyes.

    Such a close and powerful eruption raises the question of whether an even larger influx of gamma rays, disturbing the atmosphere, was responsible for one of the mass extinctions known to have occurred on Earth hundreds of millions of years ago. Also, if giant flares can be this powerful, then some gamma-ray bursts (thought to be very distant black-hole-forming star explosions) could actually be from neutron star eruptions in nearby galaxies.

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    Image/animation above: Image 2: An artist conception of the SGR 1806-20 magnetar including magnetic field lines. After the initial flash, smaller pulsations in the data suggest hot spots on the rotating magnetar’s surface. The data also shows no change in the magentar’s rotation after the initial flash.Credit: NASA

    NASA’s [2005] newly launched Swift satellite and the NSF-funded [NRAO] Very Large Array (VLA) were two of many observatories that observed the event, arising from neutron star SGR 1806-20, about 50,000 light years from Earth in the constellation Sagittarius.

    NASA SWIFT Telescope
    NASA/Swift

    NRAO VLA
    Karl V Jansky NRAO VLA

    “This might be a once-in-a-lifetime event for astronomers, as well as for the neutron star,” said Dr. David Palmer of Los Alamos National Laboratory, lead author on a paper describing the Swift observation. “We know of only two other giant flares in the past 35 years, and this December event was one hundred times more powerful.”
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    Image/animation above: Image 3: Radio data shows a very active area around SGR1806-20. The Very Large Array radio telescope observed ejected material from this Magnetar as it flew out into interstellar space. These observations in the radio wavelength start about 7 days after the flare and continue for 20 days. They show SGR1806-20 dimming in the radio spectrum. Credit: NRAO/CfA/Gaensler & Univ. of Hawaii.

    Dr. Bryan Gaensler of the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., is lead author on a report describing the VLA observation, which tracked the ejected material as it flew out into interstellar space. Other key scientific teams are associated with radio telescopes in Australia, The Netherlands, United Kingdom, India and the United States, as well as with NASA’s High Energy Solar Spectroscopic Imager (RHESSI).

    NASA RHESSI
    NASA RHESSI

    A neutron star is the core remains of a star once several times more massive than our Sun. When such stars deplete their nuclear fuel, they explode — an event called a supernova. The remaining core is dense, fast-spinning, highly magnetic, and only about 15 miles in diameter. Millions of neutron stars fill our Milky Way galaxy.

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    Image/animation above: Image 4: SGR-1806 is an ultra-magnetic neutron star, called a magnetar, located about 50,000 light years away from Earth in the constellation Sagittarius. Credit: NASA

    Scientists have discovered about a dozen ultrahigh-magnetic neutron stars, called magnetars. The magnetic field around a magnetar is about 1,000 trillion gauss, strong enough to strip information from a credit card at a distance halfway to the moon. (Ordinary neutron stars measure a mere trillion gauss; the Earth’s magnetic field is about 0.5 gauss.)

    Four of these magnetars are also called soft gamma repeaters, or SGRs, because they flare up randomly and release gamma rays. Such episodes release about 10^30 to 10^35 watts for about a second, or up to millions of times more energy than our Sun. For a tenth of a second, the giant flare on SGR 1806-20 unleashed energy at a rate of about 10^40 watts. The total energy produced was more than the Sun emits in 150,000 years.

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    Image/animation above: Image 5: Swift is a first-of-its-kind multi-wavelength observatory dedicated to the study of gamma ray burst (GRB) science. Its three instruments will work together to observe GRBs and afterglows in the gamma ray, X-ray, ultraviolet, and optical wavebands. Swift is designed to solve the 35-year-old mystery of the origin of gamma-ray bursts. Scientists believe GRB are the birth cries of black holes. Credit: NASA

    “The next biggest flare ever seen from any soft gamma repeater was peanuts compared to this incredible December 27 event,” said Gaensler. “Had this happened within 10 light years of us, it would have severely damaged our atmosphere. Fortunately, all the magnetars we know of are much farther away than this.”

    A scientific debate raged in the 1980s over whether gamma-ray bursts were star explosions from beyond our Galaxy or eruptions on nearby neutron stars. By the late 1990s it became clear that gamma-ray bursts did indeed originate very far away and that SGRs were a different phenomenon. But the extraordinary giant flare on SGR 1806-20 reopens the debate, according to Dr. Chryssa Kouveliotou of NASA Marshall Space Flight Center, who coordinated the multiwavelength observations.

    6
    Image/animation above: Image 6: NASA’s Swift satellite was successfully launched Saturday, November 20, 2004 from the Cape Canaveral Air Force Station, Fla. Credit: NASA

    A sizeable percentage of “short” gamma-ray bursts, less than two seconds, could be SGR flares, she said. These would come from galaxies within about a 100 million light years from Earth. (Long gamma-ray bursts appear to be black-hole-forming star explosions billions of light years away.)

    “An answer to the ‘short’ gamma-ray burst mystery could come any day now that Swift is in orbit”, said Swift lead scientist Neil Gehrels. “Swift saw this event after only about a month on the job.”

    7
    8
    Image Above: High resolution, wide-field image of the area around SGR1806-20 as seen in radio wavelength, without a location arrow. Credit: University of Hawaii. Image below: A high resolution, wide-field image of the area around SGR1806-20 as seen in radio wavelength. SGR1806-20 can not be seen in this image generated from earlier radio data taken when SGR1806-20 was “radio quiet.” The arrow locates the position of SGR1806-20 within the image. Credit: University of Hawaii.

    Scientists around the world have been following the December 27 event. RHESSI detected gamma rays and X-rays from the flare. Drs. Kevin Hurley and Steven Boggs of the University of California, Berkeley, are leading the effort to analyze these data. Dr. Robert Duncan of the University of Texas at Austin and Dr. Christopher Thompson at the Canadian Institute for Theoretical Astrophysics (University of Toronto) are the leading experts on magnetars, and they are investigating the “short duration” gamma-ray burst relationship.

    Brian Cameron, a graduate student at Caltech under the tutorage of Prof. Shri Kulkarni, leads a second scientific paper based on VLA data. Amateur astronomers detected the disturbance in the Earth’s ionosphere and relayed this information through the American Association of Variable Star Observers (http://www.aavso.org).

    9
    Image above: SGR 1806-20 is a “magnetar”: a rapidly spinning neutron star that not only has an incredible density, trillions of times greater than than ordinary matter, but an incredibly strong magnetic field. Tens of thousands of years ago, a “starquake” fractured the magnetar’s surface. The result was an explosive release of energy, which sent a pulse of gamma rays racing across the cosmos at the speed of light. Behind them came the explosion’s fireball, expanding in a lopsided fashion at roughly one-third the speed of light. The gamma rays swept past the Earth on December 27, 2004, when they were detected by NASA’s Swift satellite. That initial signal faded away within minutes. But then came a steady stream of radio waves from the fireball. Astronomers rushed to ground-based radio telescopes such as NSF’s Very Large Array outside Socorro, New Mexico, where they have been studying the information-rich signal ever since. Credit: NSF

    Other observatories and scientific representatives include:

    Westerbork Synthesis Radio Telescope, Netherlands — Prof. Ralph Wijers
    http://www.astron.nl/p/observing.htm
    Westerbork Synthesis Radio Telescope
    Westerbork Synthesis Radio Telescope

    Molonglo Observatory Synthesis Telescope (MOST), Australia — Prof. Dick Hunstead
    http://www.physics.usyd.edu.au/astrop/most/
    Sidney MOST
    Sidney MOST

    Australia Telescope Compact Array [ACA]– Prof. Bryan Gaensler
    http://www.narrabri.atnf.csiro.au/
    Australian Telescope Compact Array
    ACA

    Parkes radio telescope, Australia — Dr. Maura McLaughlin
    http://www.parkes.atnf.csiro.au/
    CSIRO Parkes Observatory
    Parkes

    Greenbank Radio Telescope [GBT], West Virginia — Dr. Maura McLaughlin
    http://www.gb.nrao.edu/
    NRAO GBT
    GBT

    Very Long Baseline Array [VLBA], USA — Dr. Mike Garrett
    http://www.vlba.nrao.edu/
    NRAO VLBA
    VLBA

    Multi-Element Radio Linked Interferometer Network (MERLIN), UK — Dr. Rob Fender
    http://www.merlin.ac.uk/
    Jodrell Bank Merlin
    Multi-Element Radio Linked Interferometer Network (MERLIN), UK

    Additional information about magentars and soft gamma ray repeaters can be found at Dr. Robert Duncan’s web site located at the University of Texas at Austin: http://solomon.as.utexas.edu/~duncan/magnetar.html

    See the full article here . Some images have an animation, which you can see at the original article.

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  • richardmitnick 3:13 pm on August 14, 2015 Permalink | Reply
    Tags: , , Magnetar,   

    From SPACE.com: “Why Magnetars Should Freak You Out” 

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    SPACE.com

    August 14, 2015
    Paul Sutter

    1
    Artist’s impression of the magnetar in star cluster Westerlund 1. Credit: ESO/L. Calçada

    I’ll be honest: Magnetars freak me out. But to get to the “why,” I have to explain the “what.” Magnetars are a special kind of neutron star, and neutron stars are a special kind of dead star.

    They’re easy enough to make — if you’re a massive star. All stars fuse hydrogen into helium deep in their cores. The energy released supports the stars against the crushing weight of their own gravity and, as a handy byproduct, provides the warmth and light necessary for life on any orbiting planets. But eventually, that fuel in the core runs out, allowing gravity to temporarily win and crush the star’s core even tighter.

    With the greater pressure, it becomes helium’s turn to fuse, combining into oxygen and carbon, until the helium, too, gives out. That’s where our own sun gets off the fusion train, but more massive stars can keep on chugging along, climbing up the periodic table in ever more intense and short-lived reaction phases, all the way up to nickel and iron.

    Once that solid lump of nickel and iron forms in the stellar core, a lot of things go haywire — fast. There’s still a lot of star stuff left in the atmosphere, pressing into that core, but further fusion doesn’t release energy, so there’s nothing left to prevent collapse.

    And collapse it does: The nickel and iron nuclei (yes, just nuclei; don’t even think about entire atoms at these temperatures and pressures) break apart. They just can’t handle this nuclear mosh pit. Stray electrons get shoved into the nearest protons, converting them to neutrons. The neutrons … stay neutrons. And those neutrons are mighty good at preventing further collapse, for reasons I’ll explain in a bit. The infalling gas, trying to crush the core into oblivion, bounces off that neutron core and goes kablamo! (Note: I don’t know what it actually sounds like.)

    The neutron ball

    What happens during the supernova event is an exciting discussion for another day. What we’re concerned with now is the leftovers: a soupy, ball-like mixture of neutrons and a few straggler protons. This ball is supported against its own weight by “degeneracy pressure,” which is a fancy way of saying that you can only pack so many neutrons in box — or, in this case, a ball. It may seem obvious that neutrons, well, take up space, but things didn’t have to turn out this way. It’s this degeneracy pressure that causes the big bounce that puts the super in supernova.

    I should note that, if there’s still too much stuff left hanging out around this leftover neutron ball, the weight can overwhelm even degeneracy pressure. And now, look what you’ve done: You’ve gone and made a black hole. But that, too, is another story. We wouldn’t want to be like our poor star and get overwhelmed.

    The neutron ball — which I should now call by its proper name, a neutron star — is weird. Seriously, that’s the best word I can find to describe it. Neutron stars are basically city-size atomic nuclei, which makes them among the densest things in the universe. The pressure of gravity inside these stars has squeezed apart even atomic nuclei, allowing their bits to float freely.

    It’s mostly neutrons down there — hence the name — but there are also a few surviving protons floating around. Normally, those protons would repel one another, being like-minded charges and all, but they are forced close together as the Strong Nuclear Force tries to bunch them up with their fellow neutrons.

    The neutron star’s interior is a complicated dance of physics under extreme conditions, resulting in very odd structures. The oddity starts near the surface, with blobs of a few hundred neutrons that are best described as neutron gnocchi. Below that, the neutron blobs glue together into long chains. We have entered the spaghetti layer. Underneath that, at even more extreme pressures, the spaghetti strands fuse side by side and form lasagna sheets. Under it all, even neutron lasagna loses its shape, becoming a uniform mass. But that mass has gaps in it, in the form of long tubes. At last: delicious penne.

    I wish I were making these names up, but physicists must be especially hungry people when coming up with metaphors.

    Did I mention the spinning? Oh yes, neutron stars spin, up to a few hundred times per second. Let all of this sink in for a bit: An object with such strong gravity that “hills” are barely a few millimeters tall, rotating with a speed that could rival your kitchen blender. We’re not playing games anymore.

    Neutron stars are scary

    All this action — the insane densities, the complicated structures, the ridiculously fast rotation rates — means that neutron stars carry some pretty nasty magnetic fields. But don’t magnetic fields require charged particles, and aren’t neutrons neutral? That’s true, smartypants, but there are still a few protons hanging out in the star, and at these incredible densities, physics gets … complicated. So, yes: Neutron stars, despite their name, can carry magnetic fields.

    How strong? Take a star’s normal magnetic field, and squish it down. Every time you squish, you get a stronger field, just as you get higher densities. And we’re squishing something from star-size (a million kilometers or miles, take your pick) to city-size (like, 25 kilometers — just 15 miles). Plus, with all the interesting physics happening in the interiors, complex processes can operate to amplify the magnetic field, so you can imagine just how strong those fields get.

    Actually, you don’t have to imagine, because I’m about to tell you. Let’s start with something familiar: the Earth’s magnetic field. That’s around 1 gauss. It’s not much different for the sun: a few to a few hundred gauss, depending on where on the surface you are. An MRI? 10,000 gauss. The strongest human-made magnetic fields are about a few hundred thousand gauss. In fact, we can’t make magnetic fields stronger than a million gauss or so without our machines just breaking down from the stress.

    Let’s cut to the chase: A neutron star carries a whopping trillion-gauss magnetic field. You read that right — “trillion,” with a “t.”

    Enter the magnetar

    Now, we finally get to magnetars. You may guess from the name that they’re especially magnetic: up to 1 quadrillion gauss. That’s 1,000 trillion times stronger than the magnetic field you’re sitting in right now. That puts magnetars in the No. 1 spot, reigning champions in the universal Strongest Magnetic Field competition. The numbers are there, but it’s hard to wrap our brains around them.

    Those fields are strong enough to wreak havoc on their local environments. You know how atoms are made of a positively charged nucleus surrounded by negatively charged electrons? Those charges respond to magnetic fields. Not very much under normal conditions, but this ain’t Kansas anymore, is it, Toto? Any unlucky atoms stretch into pencil-thin rods near these magnetars.

    It doesn’t stop there. With the atoms all screwed up, normal molecular chemistry is just a no-go. Covalent bonds? Ha! And the magnetic fields can drive enormous bursts of high-intensity radiation. So, generally bad business.

    Get too close to one (say, within 1,000 kilometers, or about 600 miles), and the magnetic fields are strong enough to upset not just your bioelectricity — rendering your nerve impulses hilariously useless — but your very molecular structure. In a magnetar’s field, you just kind of … dissolve.

    We’re not exactly sure what makes magnetars so frighteningly magnetic. Like I said, the physics of neutron stars is a little bit sketchy. It does seem, though, that magnetars don’t last long, and after 10,000 years (give or take), they settle down into a long-term normal neutron-star retirement: still insanely dense, still freaky magnetic, just…not so bad.

    So, as scary as they are, at least they won’t stay that way for long.

    See the full article here.

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  • richardmitnick 12:27 pm on July 8, 2015 Permalink | Reply
    Tags: , , , , , Magnetar   

    From ESO: “Biggest Explosions in the Universe Powered by Strongest Magnets” 


    European Southern Observatory

    8 July 2015
    Jochen Greiner
    Max-Planck Institut für extraterrestrische Physik
    Garching, Germany
    Tel: +49 89 30000 3847
    Email: jcg@mpe.mpg.de

    Richard Hook
    ESO Public Information Officer
    Garching bei München, Germany
    Tel: +49 89 3200 6655
    Cell: +49 151 1537 3591
    Email: rhook@eso.org

    1

    Observations from ESO’s La Silla and Paranal Observatories in Chile have for the first time demonstrated a link between a very long-lasting burst of gamma rays and an unusually bright supernova explosion. The results show that the supernova was not driven by radioactive decay, as expected, but was instead powered by the decaying super-strong magnetic fields around an exotic object called a magnetar. The results will appear in the journal Nature on 9 July 2015.

    Gamma ray bursts (GRBs) are one of the outcomes associated with the biggest explosions to have taken place since the Big Bang. They are detected by orbiting telescopes that are sensitive to this type of high-energy radiation, which cannot penetrate the Earth’s atmosphere, and then observed at longer wavelengths by other telescopes both in space and on the ground.

    GRBs usually only last a few seconds, but in very rare cases the gamma rays continue for hours [1]. One such ultra-long duration GRB was picked up by the Swift satellite on 9 December 2011 and named GRB 111209A. It was both one of the longest and brightest GRBs ever observed.

    NASA SWIFT Telescope
    NASA/Swift

    As the afterglow from this burst faded it was studied using both the GROND instrument on the MPG/ESO 2.2-metre telescope at La Silla and also with the X-shooter instrument on the Very Large Telescope (VLT) at Paranal. The clear signature of a supernova, later named SN 2011kl, was found. This is the first time that a supernova has been found to be associated with an ultra-long GRB [2].

    ESO GROND Instrument
    GROND

    ESO X-shooter
    X-shooter instrument

    The lead author of the new paper, Jochen Greiner from the Max-Planck-Institut für extraterrestrische Physik, Garching, Germany explains: “Since a long-duration gamma-ray burst is produced only once every 10 000–100 000 supernovae, the star that exploded must be somehow special. Astronomers had assumed that these GRBs came from very massive stars — about 50 times the mass of the Sun — and that they signalled the formation of a black hole. But now our new observations of the supernova SN 2011kl, found after the GRB 111209A, are changing this paradigm for ultra-long duration GRBs.”

    In the favoured scenario of a massive star collapse (sometimes known as a Collapsar) the week-long burst of optical/infrared emission from the supernova is expected to come from the decay of radioactive nickel-56 formed in the explosion [3]. But in the case of GRB 111209A the combined GROND and VLT observations showed unambiguously for the first time that this could not be the case [4]. Other suggestions were also ruled out [5].

    The only explanation that fitted the observations of the supernova following GRB 111209A was that it was being powered by a magnetar — a tiny neutron star spinning hundreds of times per second and possessing a magnetic field much stronger than normal neutron stars, which are also known as radio pulsars [6]. Magnetars are thought to be the most strongly magnetised objects in the known Universe. This is the first time that such an unambiguous connection between a supernova and a magnetar has been possible.

    Paolo Mazzali, co-author of the study, reflects on the significance of the new findings: “The new results provide good evidence for an unexpected relation between GRBs, very bright supernovae and magnetars. Some of these connections were already suspected on theoretical grounds for some years, but linking everything together is an exciting new development.”

    “The case of SN 2011kl/GRB 111209A forces us to consider an alternative to the collapsar scenario. This finding brings us much closer to a new and clearer picture of the workings of GRBs,” concludes Jochen Greiner.
    Notes

    [1] Normal long-duration GRBs last between 2 and 2000 seconds. There are now four GRBs known with durations between 10 000–25 000 seconds — these are called ultra-long GRBs. There is also a distinct class of shorter-duration GRBs that are believed to be created by a different mechanism.

    [2] The link between supernovae and (normal) long-duration GRBs was established initially in 1998, mainly by observations at ESO observatories of the supernova SN 1998bw, and confirmed in 2003 with GRB 030329.

    [3] The GRB itself is thought to be powered by the relativistic jets produced by the star’s material collapsing onto the central compact object via a hot, dense accretion disc.

    [4] The amount of nickel-56 measured in the supernova with the GROND instrument is much too large to be compatible with the strong ultraviolet emission as seen with the X-shooter instrument.

    [5] Other suggested sources of energy to explain superluminous supernovae were shock interactions with the surrounding material — possibly linked to stellar shells ejected before the explosion — or a blue supergiant progenitor star. In the case of SN 2011kl the observations clearly exclude both of these options.

    [6] Pulsars make up the most common class of observable neutron stars, but magnetars are thought to develop magnetic field strengths that are 100 to 1000 times greater than those seen in pulsars.
    More information

    This research was presented in a paper entitled “A very luminous magnetar-powered supernova associated with an ultra-long gamma-ray burst”, by J. Greiner et al., to appear in the journal Nature on 9 July 2015.

    The team is composed of Jochen Greiner (Max-Planck-Institut für extraterrestrische Physik, Garching, Germany [MPE]; Excellence Cluster Universe, Technische Universität München, Garching, Germany), Paolo A. Mazzali (Astrophysics Research Institute, Liverpool John Moores University, Liverpool, England; Max-Planck-Institut für Astrophysik, Garching, Germany [MPA]), D. Alexander Kann (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany), Thomas Krühler (ESO, Santiago, Chile) , Elena Pian (INAF, Institute of Space Astrophysics and Cosmic Physics, Bologna, Italy; Scuola Normale Superiore, Pisa, Italy), Simon Prentice (Astrophysics Research Institute, Liverpool John Moores University, Liverpool, England), Felipe Olivares E. (Departamento de Ciencias Fisicas, Universidad Andres Bello, Santiago, Chile), Andrea Rossi (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany; INAF, Institute of Space Astrophysics and Cosmic Physics, Bologna, Italy), Sylvio Klose (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany) , Stefan Taubenberger (MPA; ESO, Garching, Germany), Fabian Knust (MPE), Paulo M.J. Afonso (American River College, Sacramento, California, USA), Chris Ashall (Astrophysics Research Institute, Liverpool John Moores University, Liverpool, England), Jan Bolmer (MPE; Technische Universität München, Garching, Germany), Corentin Delvaux (MPE), Roland Diehl (MPE), Jonathan Elliott (MPE; Harvard-Smithsonian Center for Astrophysics, Cambridge, Massachusetts, USA), Robert Filgas (Institute of Experimental and Applied Physics, Czech Technical University in Prague, Prague, Czech Republic), Johan P.U. Fynbo (DARK Cosmology Center, Niels-Bohr-Institut, University of Copenhagen, Denmark), John F. Graham (MPE), Ana Nicuesa Guelbenzu (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany), Shiho Kobayashi (Astrophysics Research Institute, Liverpool John Moores University, Liverpool, England), Giorgos Leloudas (DARK Cosmology Center, Niels-Bohr-Institut, University of Copenhagen, Denmark; Department of Particle Physics & Astrophysics, Weizmann Institute of Science, Israel), Sandra Savaglio (MPE; Universita della Calabria, Italy), Patricia Schady (MPE), Sebastian Schmidl (Thüringer Landessternwarte Tautenburg, Tautenburg, Germany), Tassilo Schweyer (MPE; Technische Universität München, Garching, Germany), Vladimir Sudilovsky (MPE; Harvard-Smithonian Center for Astrophysics, Cambridge, Massachusetts, USA), Mohit Tanga (MPE), Adria C. Updike (Roger Williams University, Bristol, Rhode Island, USA), Hendrik van Eerten (MPE) and Karla Varela (MPE)..

    See the full article here.

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  • richardmitnick 9:24 am on September 1, 2014 Permalink | Reply
    Tags: , , , , , Magnetar   

    From ESA: “Magnetar discovered close to supernova remnant Kesteven 79” 

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    European Space Agency

    01/09/2014
    Massive stars end their life with a bang, exploding as supernovas and releasing massive amounts of energy and matter. What remains of the star is a small and extremely dense remnant: a neutron star or a black hole.

    bh
    ESA/XMM-Newton/ Ping Zhou, Nanjing University, China

    Neutron stars come in several flavours, depending on properties such as their ages, the strength of the magnetic field concealed beneath their surface, or the presence of other stars nearby. Some of the energetic processes taking place around neutron stars can be explored with X-ray telescopes, like ESA’s XMM-Newton.

    ESA XMM Newton
    ESA/XMM-Newton

    This image depicts two very different neutron stars that were observed in the same patch of the sky with XMM-Newton. The green and pink bubble dominating the image is Kesteven 79, the remnant of a supernova explosion located about 23,000 light-years away from us.

    From the properties of the hot gas in Kesteven 79 and from its size, astronomers estimate that it is between 5000 and 7000 years old. Taking account of the time needed for light to travel to Earth, this means that the supernova that created it must have exploded almost 30,000 years ago. The explosion left behind a a young neutron star with a weak magnetic field, which can be seen as the blue spot at the centre of Kesteven 79.

    Beneath it, a blue splotch indicates an entirely different beast: a neutron star boasting an extremely strong magnetic field, known as a magnetar. Astronomers discovered this magnetar, named 3XMM J185246.6+003317, in 2013 by looking at images that had been taken in 2008 and 2009. After the discovery, they looked at previous images of the same patch of the sky, taken before 2008, but did not find any trace of the magnetar. This suggests that the detection corresponded to an outburst of X-rays released by the magnetar, likely caused by a dramatic change in the structure of its magnetic field.

    While the neutron star in the supernova remnant is relatively young, the magnetar is likely a million years old; the age difference means that it is very unlikely that the magnetar arose from the explosion that created Kesteven 79, but must have formed much earlier.

    This false-colour image is a composite of 15 observations performed between 2004 and 2009 with the EPIC MOS camera on board XMM-Newton. The image combines data collected at energies from 0.3 to 1.2 keV (shown in red), 1.2 to 2 keV (shown in green) and 2 to 7 keV (shown in blue).

    epic mos

    See the full article here.

    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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