Superluminous Supernova 20 Times Brighter Than 100 Billion Stars Wows Astronomers

Records are made to be broken, as the expression goes, but rarely are records left so thoroughly in the dust. Stunned astronomers have witnessed a cosmic explosion about 200 times more powerful than a typical supernova--events which already rank amongst the mightiest outbursts in the universe--and more than twice as luminous as the previous record-holding supernova. At its peak intensity, the explosion--called ASASSN-15lh--shone with 570 billion times the brightness of the Sun. If that statistic does not impress, consider that this luminosity level is approximately 20 times the entire output of the 100 billion stars comprising our Milky Way galaxy. The record-breaking blast is thought to be an outstanding example of a "superluminous supernova," a recently discovered, supremely rare variety of explosion unleashed by certain stars when they die. Scientists are frankly at a loss, though, regarding what sorts of stars and stellar scenarios might be responsible for these extreme supernovae. These are pseudo-color images showing the host galaxy before the explosion of ASASSN-15lh taken by the Dark Energy Camera (DECam) [Left], and the supernova by the Las Cumbres Observatory Global Telescope Network (LCOGT) 1-meter telescope network [Right]. As described in a new study published today in Science, ASASSN-15lh Credit: The...
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Earth Collects 5 to 300 Tons of Cosmic Dust a Day

Image credit: ESO/Y. Beletsky Currently, estimates of the Earth's intake of space dust vary from around five tons to as much as 300 tons every day. A €2.5 million international project, led by Professor John Plane from the University's School of Chemistry, will seek to address this discrepancy. Scientists at the University of Leeds are looking to discover how dust particles in the solar system interact with the Earth's atmosphere. Currently, estimates of the Earth's intake of space dust vary from around five tons to as much as 300 tons every day. A € 2.5 million international project, led by ERC Advanced grantee John Plane from the University's School of Chemistry, will seek to address this discrepancy. The Cosmic Dust in the Terrestrial Atmosphere (CODITA) project will investigate what happens to the dust from its origin in the outer solar system all the way to the earth's surface. The work, funded by the European Research Council, will also explore whether cosmic dust has a role in the Earth's climate and how it interacts with the ozone layer in the stratosphere. "People tend to think space is completely empty, but if all the dust between the Sun and Jupiter was compressed it would create a moon 16 miles across. It's surprising that we aren't more certain how much of this comes to Earth" said Professor Plane. "If the dust...
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Brighter Than 100 Billion Stars

Three-dimensional simulation of a Type Ia supernova explosion, Image: F. K. Röpke MPI for Astrophysics, Garching Modern astronomy began with a supernova. In November 1572, Danish astronomer Tycho Brahe discovered a new star – and destroyed the idea of a sky of fixed stars. Today, we know that Brahe was observing the death of a star, which ended in a massive explosion. Friedrich Röpke aims to find out how these supernova explosions proceed. The astrophysicist is now leader of the new research group "Physics of Stellar Objects" (PSO) at Heidelberg Institute for Theoretical Studies (HITS). As of March 1, 2015, he has been appointed professor for Theoretical Astrophysics at Heidelberg University. His workplace is HITS. This joint appointment is a perfect proof for the close cooperation between the two institutes. With Friedrich Röpke and Volker Springel, there now are two HITS astrophysicists who are also professors at Heidelberg University. “The new group is another important component of our concept, “ says Klaus Tschira who founded the HITS in 2010 as a non-profit research institute. “Research on stellar astrophysics, like Friedrich Röpke does, is a perfect complement of the work of Volker Springel’s group on large-scale processes like galaxy formation.“ Friedrich Röpke (40) studied Physics at the University of Jena and the...
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Two Stars Merging Into A Supermassive Star Seen By Astronomers

Credit: Javier Lorenzo (Universidad de Alicante) A study of "MY Camelopardalis" binary system, published in the journal Astronomy & Astrophysics, shows that the most massive stars are made up by merging with other smaller stars, as predicted by theoretical models. Most of the stars in our galaxy have been formed in binary or multiple systems, some of which are "eclipsing", this is consists of two or more stars which, observed from Earth, undergo eclipses and mutual transits because of their orbital plane facing our planet. One such system is the eclipsing binary MY Camelopardalis (MY Cam). Artistic rendering of MY Cam system. The proportions between the components reflect the analysis results. The stars are deformed by its very fast rotation and the gravitational pull of the companion. The journal Astronomy & Astrophysics has published an article on MY Cam, one of the most massive star known, with the results of observations from the Calar Alto Observatory (Almería) signed by astronomers at the University of Alicante, the Astrobiology Centre of the Spanish National Research Council (CAB-CSIC) and the Canaries’ Astrophysics Institute (IAC), along with amateur astronomers. This article concludes that MY Cam is the most massive binary star observed and its components, two stars of spectral type O (blue, very hot and...
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Astronomers Create First Realistic Virtual Universe

Credit: Dr Debora Sijacki, Cambridge University Tracking 13 billion years of cosmic evolution, astronomers have created the first realistic virtual simulation of the Universe. A newly-developed computer simulation has created the first realistic version of the Universe, enabling researchers to understand how galaxies, black holes and other cosmic phenomena developed from shortly after the Big Bang to the present day. The simulation, known as Illustris, follows the complex development of both normal and dark matter over 13 billion years, matching many of the features observed in the real Universe for the first time. Developed by an international team of researchers, Illustris tracks the development of the Universe from 12 million years after the Big Bang up to the present, and identified more than 41,000 galaxies in a cube of simulated space 350 million light years on each side. The results are reported in the May 8th issue of the journal Nature.  Over the past two decades, researchers have been attempting to build accurate computer simulations of the development of the Universe, using computer programs which are capable of encapsulating all the relevant laws of physics governing the formation of galaxies. Previous attempts to simulate the universe were hampered by lack of computing power and the complexities of the...
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