Keyword: neutronstars
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"This is the first time we've been able to verify that metals heavier than iron and silver were freshly made in front of us." An illustration of two neutron stars colliding and merging to create a kilonova blast. (Image credit: Robin Dienel/Carnegie Institution for Science) Scientists have analyzed an unusually long blast of high-energy radiation, known as a gamma-ray burst (GRB), and determined that it originated from the collision of two ultradense neutron stars. And, importantly, this result helped the team observe a flash of light emanating from the same event that confirms these mergers are the sites that create...
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Explanation: The hydrogen in your body, present in every molecule of water, came from the Big Bang. There are no other appreciable sources of hydrogen in the universe. The carbon in your body was made by nuclear fusion in the interior of stars, as was the oxygen. Much of the iron in your body was made during supernovas of stars that occurred long ago and far away. The gold in your jewelry was likely made from neutron stars during collisions that may have been visible as short-duration gamma-ray bursts or gravitational wave events. Elements like phosphorus and copper are present...
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Visible Milky Way Galaxy Versus Its Galactic Underworld Split view of the visible Milky Way galaxy versus its galactic underworld. Credit: University of Sydney A new study creates the first map of our galaxy’s ancient dead stars. In the first map of the ‘galactic underworld’, a study from the University of Sydney has revealed a vast graveyard that stretches three times the height of the Milky Way. It has also indicated where the dead stars lie. A graveyard that stretches three times the height of the Milky Way has been revealed in the first map of the ‘galactic underworld’ –...
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Astronomers have discovered black widows and redbacks in space. While these cosmic objects don't kill and eat their mates, the stars share their eight-legged counterparts' violent behavior toward companions. In addition to the run-of-the-mill spider stars, the researchers also discovered a bizarre black widow-redback crossbreed. The scientists used the now-destroyed Arecibo telescope in Puerto Rico to discover the weirdo stars. Spider stars are types of millisecond pulsars, or neutron stars that act like precise clocks in the sky, whirling around at least once every 30 milliseconds and flashing like a lighthouse with each rotation. Neutron stars, the tiny, compressed cores...
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Gold is an element, which means you can't make it through ordinary chemical reactions — though alchemists tried for centuries. To make the sparkly metal, you have to bind 79 protons and 118 neutrons together to form a single atomic nucleus. That's an intense nuclear fusion reaction. But such intense fusion doesn't happen frequently enough, at least not nearby, to make the giant trove of gold we find on Earth and elsewhere in the solar system. And a new study has found the most commonly-theorized origin of gold — collisions between neutron stars — can't explain gold's abundance either. So...
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When humanity finally detected the collision between two neutron stars in 2017, we confirmed a long-held theory - in the energetic fires of these incredible explosions, elements heavier than iron are forged. And so, we thought we had an answer to the question of how these elements - including gold - propagated throughout the Universe. But a new analysis has revealed a problem. According to new galactic chemical evolution models, neutron star collisions don't even come close to producing the abundances of heavy elements found in the Milky Way galaxy today. "Neutron star mergers did not produce enough heavy elements...
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A source of repeating radio waves seen from one point in the sky presents astronomers with numerous mysteries. The source of this signal, where radiation builds and ebbs over a period of 16 days, remains a question. The longevity of these cycles — now seen continuing for over 500 days — could either present another mystery, or perhaps a clue to what is going on at the center of these displays. Fast radio bursts (FRBs) are one form of highly-energetic explosion in deep space. Thought to be caused by small, massive objects, although the exact nature of these objects is...
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Earth's gravitational wave observatories -- which hunt for ripples in the fabric of space-time -- just picked up something weird. The Laser Interferometer Gravitational-Wave Observatory (LIGO) and Virgo detectors recorded an unknown or unanticipated "burst" of gravitational waves on Jan. 14. The gravitational waves we've detected so far usually relate to extreme cosmic events, like two black holes colliding or neutron stars finally merging after being caught in a death spiral. Burst gravitational waves have not been detected before and scientists hypothesize they may be linked to phenomena such as supernova or gamma ray bursts, producing a tiny "pop" when...
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A mysterious repeating radio signal from space revealed last year is now the fifth fast radio burst to be tracked back to its source galaxy. It's a location unlike any of the others, and astronomers are having to rethink their previous assumptions about how these signals are generated. The origin of this repeating signal is a spiral galaxy, located 500 million light-years from Earth, making it the closest known source of what we call fast radio bursts (FRBs) yet. And the FRBs are emanating specifically from a region just seven light-years across - a region that's alive with star formation....
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Measurements of gravitational waves from approximately 50 binary neutron stars over the next decade will definitively resolve an intense debate about how quickly our universe is expanding, according to findings from an international team that includes University College London (UCL) and Flatiron Institute cosmologists. When neutron stars collide, they emit light and gravitational waves, as seen in this artist's illustration. By comparing the timing of the two emissions from many different neutron star mergers, researchers can measure how fast the universe is expanding. Credit: R. Hurt/Caltech-JPL The cosmos has been expanding for 13.8 billion years. Its present rate of expansion,...
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David Coulter was in Copenhagen when he got an email that catapulted him into the stars. Coulter, 36, is a self-taught programmer. He spent 10 years in industry jobs, then left for graduate studies in astronomy and astrophysics at UC Santa Cruz, which operates Lick Observatory on Mount Hamilton. “I just wanted to learn about outer space,” he said. He picked the right place. The second-year grad student found himself on a team that was the first to take images of neutron stars merging, beating a group from Harvard, perhaps explaining the origin of metals such as gold and uranium....
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The observations indicate that the waves and light came from a pair of merging neutron stars about 130 million light-years away, according to a news conference on Monday Oct. 16, 2017. Neutron stars are the incredibly dense remnants of stars that have exploded in supernovas. The two that merged were 1.6 and 1.1 times as massive as our sun, but each was no wider than Washington, D.C., according to a statement by the Space Telescope Science Institute. As the stars spiraled into each other, they sent gravitational waves through the universe and released tremendous amounts of light when they finally...
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For the first time, two neutron stars in a nearby galaxy have been observed engaging in a spiral death dance around one another until they collided. What resulted from that collision is being called an "unprecedented" discovery that is ushering in a new era of astronomy, scientists announced Monday.
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Astrophysicists may have detected gravitational waves last week from the collision of two neutron stars in a distant galaxy — and telescopes trained on the same region might also have spotted the event. Rumours to that effect are spreading fast online, much to researchers’ excitement. Such a detection could mark a new era of astronomy: one in which phenomena are both seen by conventional telescopes and ‘heard’ as vibrations in the fabric of space-time. “It would be an incredible advance in our understanding,” says Stuart Shapiro, an astrophysicist at the University of Illinois at Urbana–Champaign. Scientists who work with gravitational-wave...
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CalTech astronomer Fritz Zwicky was the first to conceive of dark matter, supernovas and neutron stars. He also had a theory about colonizing the solar system using nuclear bombs. We could terraform other planets, he argued, by pulverizing them and then moving them closer or further from the sun. ...
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Intense pressure can force neutrons into cubes rather than spheres, say physicistsInside atomic nuclei, protons and neutrons fill space with a packing density of 0.74, meaning that only 26 percent of the volume of the nucleus in is empty. That's pretty efficient packing. Neutrons achieve a similar density inside neutron stars, where the force holding neutrons together is the only thing that prevents gravity from crushing the star into a black hole. Today, Felipe Llanes-Estrada at the Technical University of Munich in Germany and Gaspar Moreno Navarro at Complutense University in Madrid, Spain, say neutrons can do even better. These...
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Superfluids are strange states of matter, typically forming at very low and very high temperatures, exhibiting gonzo properties like a seemingly gravity-defying tendency to climb up the walls of containers and friction-free superconductivity. That is, they are perfect conductors that don't lose energy during transmission. And the fact that they appear to exist at the center of neutron stars tells scientists a lot about nuclear interactions in high-density matter and the life-cycles of neutron stars. The pressure within neutron stars is so intense that in the stars' cores, charged particles merge, resulting in a star mostly consisting of neutrons (hence...
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