In 2013, Archibald and her colleagues found an unusual triple system: a pulsar and a white dwarf that orbit one another, with a second white dwarf orbiting the pair.
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That's known as a Cataclysmic Variable, or CV. The normal star is losing its mass to the white dwarf, and it's 3.9 times more massive than the white dwarf.
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They've already identified the best white dwarf stars to investigate.
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Perhaps these white dwarf-black hole meetings are causing those events.
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That's nearly twice the average mass of a white dwarf star.
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Artist's concept of a neutron star's pulse warped by a white dwarf.
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Tiny spikes of hydrogen were unexpectedly detected around this particular white dwarf.
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What they found: By observing the white dwarf and the planetesimal, scientists were able to watch the planetary material "pollute" the atmosphere of the white dwarf as the dense star stripped away the outer layers of the world.
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This system consists of a spinning neutron star shooting a beam of light (called a pulsar) and a white dwarf that orbit each other every 1.6 Earth days, both of which orbit another white dwarf every 327 Earth days.
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Until now, figuring out the mass of a white dwarf has been difficult.
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Results like these help scientists understand supernovae and white dwarf stars more generally.
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And hydrogen still gets sucked from the companion star to the white dwarf.
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Our sun will explode and become a white dwarf in 5 billion years.
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Nor is there better news to be found elsewhere around the white dwarf.
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It's known as WDJ0551+4135 and appeared to be a massive white dwarf.
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Yet, these stars merged, created an ultra-massive white dwarf instead of exploding.
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Because of this theory, an old white dwarf like J0207 shouldn't have rings.
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This pulsar forms a binary with another compact object called a white dwarf.
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The Sun that the Earth orbits has died and become a white dwarf.
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The image shows a pair of stars, a red giant and a white dwarf.
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The two white dwarf stars complete an orbit around each other every seven minutes.
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These mini-novas are thought to be formed when a white dwarf partially explodes.
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That, in turn, allowed them to measure the mass of the white dwarf star.
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Artist's depiction of a white dwarf (right) in orbit around a white giant star.
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The newly discovered planetary fragment is only about 320,000 miles from the white dwarf.
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After the limit, the force of gravity would cause the white dwarf to collapse.
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Researchers believe it may be the first white dwarf known to have multiple rings.
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"Our own star will become a white dwarf," Bataller said in a phone call.
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This is the first time those gases have been identified around a white dwarf.
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The white dwarf is rotating incredibly fast due to past interactions with its companion, while the ultra-dense pulsar acts as a sort of gigantic "cosmic clock" that scientists can use to measure the frame drag of spacetime as the white dwarf spins.
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The team determined the mass of a collapsed stellar remnant called a white dwarf star.
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The system contains a pulsar and a white dwarf, two different types of dead star.
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The hourglass-shaped nebula is due to an aging red giant star and a white dwarf.
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As the red dwarf sheds material, the gravity from the white dwarf pulls the debris in.
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Eventually the red dwarf will turn into a white dwarf, and the debris dance will continue.
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Instead, they thought the remnants could have been the result of two white dwarf stars colliding.
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Now it circles the white dwarf so closely that it completes an orbit every 123 minutes.
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In this case, the brown dwarf is 10 times less massive than the dense white dwarf.
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This peculiar white dwarf, LSPM J0207+3331, is 13 light-years away in the Capricornus constellation.
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This peculiar white dwarf, LSPM J0207+3331, is 145 light-years away in the Capricornus constellation.
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But in this case, the black hole's intense gravitational pull on the white dwarf causes the explosions.
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This duo is in a 327-day orbit with the other white dwarf, which lies much farther away.
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Well, you have two objects—one is a white dwarf star, whose mass is mostly composed of matter.
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For the first time ever, researchers have spotted a white dwarf surrounded by an atmosphere of mostly oxygen.
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Eventually those outer layers are lost and only the core of the star remains — the faint white dwarf.
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The white dwarf is so dense that its extreme gravity pulls hydrogen gas off of the second star.
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The star's hot, dense core gets left behind — that's the phase at which it becomes a white dwarf.
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"We're pretty sure of how one star forms one white dwarf, and it shouldn't do this," Hollands said.
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The powerful gravity of the white dwarf pulls hydrogen away from its companion star and onto its surface.
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The researchers were able to calculate the pulsar's mass due to its interactions with its companion white dwarf.
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The planet moved closer to the white dwarf once the red giant blasted out much of its mass.
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Or maybe there was a helium shell on the surface of the white dwarf, which provided more ignition material.
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And sure enough, the more distant star shifted its position ever so slightly as the white dwarf passed by.
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Its image was captured, effectively creating a time stamp of the white dwarf star and its red dwarf star.
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Alternatively, matter can pile up onto a white dwarf star, until it gets so dense it triggers an explosion.
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The white dwarf accretes material from its partner and spews out even more matter, creating the structures seen here.
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Getting explosive: It's thought that white dwarf stars can only support so much mass because of their unique chemistry.
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The white dwarf companion was likely pilfering stellar material off its enormous star friend, which eventually sparked the explosion.
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The Sun will burn off all of its fuel and end up a white dwarf, then burn out and die.
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The resulting red dwarf / white dwarf pair, described today in the journal Nature, are indeed fainter and undergoing periodic eruptions.
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But it now orbits too close to the white dwarf for life as we know it to exist on it.
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The white dwarf fades, and the cycle repeats until the next explosion, which could be up to 100,000 years later.
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But once the asteroid belts are exhausted of their resources, the material orbiting the white dwarf settles onto the surface.
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Gänsicke said that they are interested in learning more about the composition of the giant planet orbiting the white dwarf.
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It then shrinks to form a white dwarf, while the expelled gas is slowly compressed and pushed outwards by stellar winds.
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Close approaches between these two objects would result in nuclear reactions on the white dwarf in all of the group's calculations.
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But based on long-term observations, this white dwarf star experienced periodic brightening over six years leading up to the explosion.
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Scientists at the Kitt Peak National Observatory in Arizona have spotted a half-burnt white dwarf star hurtling across the galaxy.
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For the first time, astronomers have glimpsed the bending of light from a more distant star by a nearby white dwarf.
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In these systems, one of the stars is a white dwarf, the burned out but still hot remnant of a star.
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"You get a giant fusion bomb, a hydrogen bomb going off on top of this white dwarf star," Dr. Shara said.
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The new hybrid star will have a white dwarf core surrounded by a hydrogen-burning layer and a hydrogen gas envelope.
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These events are known as Type Ia supernovae, and they only occur in binary systems with at least one white dwarf.
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It seems as if one is far hotter than a typical white dwarf, perhaps because it's sucking up matter from the other.
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Novae are explosions that occur on the surface of white dwarf stars sucking up matter from a partner in a binary system.
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They were able to then determine the mass of the white dwarf star – which had only been possible in theory until now.
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The dead star was a white dwarf, the leftover remnant of a star that has used up all its fuel and collapsed.
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A classical nova occurs in a two-star system — where a white dwarf and a companion star orbit closely around each other.
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They plan to listen for these broadcasts with telescopes on Earth in order to find dead planets orbiting distant "white dwarf" stars.
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So he and Veras created computer simulations of the entire range of magnetic fields and electrical conductivities observed in white dwarf stars.
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Once the white dwarf gobbled up as much material as it could hold, a thermonuclear explosion was triggered, resulting in a supernova.
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From red giant to white dwarf Once the sun has emptied its fuel reserves, it will become unstable and start to pulse.
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"So if the sun was positioned where the white dwarf is, the planetesimal would be orbiting within the sun," said Dr. Manser.
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This is especially interesting to us because, as we've reported, scientists predict that our own Sun's fate is to become a white dwarf.
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The white dwarf within AR Scorpii is spinning so rapidly that it kicks off electrons at relativistic speeds, approaching the speed of light.
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With Hubble, the astronomers observed this white dwarf multiple times before and after the crossing, capturing the relative movement of the background star.
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Artist impression of a rocky and water-rich asteroid being torn apart by the strong gravity of the white dwarf star GD 61.
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That hydrogen builds up around the white dwarf, and eventually it gets so hot that it erupts in an extremely bright thermonuclear reaction.
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He determined that any star remnants 1.4 times more massive than our sun would be too massive to form a stable white dwarf.
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The spike in brightness was caused by material stripped from the brown dwarf that's being coiled around the white dwarf in a disk.
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"This white dwarf is so old that whatever process is feeding material into its rings must operate on billion-year timescales," Debes said.
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V Sagittae, also known as V Sge, is a star system that includes a regular star in orbit with a white dwarf star.
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Though it was a very weak signal, one element that was present was oxygen, which had never been observed in a white dwarf.
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One of those was a white dwarf named Stein 2051 B, which was expected to pass in front of another star in March 2014.
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A type 1a supernova is a binary star in which a small, dense object called a white dwarf pulls material from a larger companion.
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The periodic bumps meant the transfer of hydrogen to the white dwarf was unstable and happening at an extremely low rate, according to Mroz.
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The waves are caused by interactions between a dead planet's core and the magnetic field of its dead star, known as a white dwarf.
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"In all other known CVs the white dwarf is more massive than the orbiting normal star, so V Sge is utterly unique," Schaefer said.
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This discovery is major progress because over the past two decades we had growing evidence that planetary systems survive into the white dwarf stage.
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The team analyzed a catalog of 15,109 white dwarf candidates within 100 parsecs (326 light-years) of our Sun using data from the Gaia satellite.
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The observations revealed that the white dwarf and the pulsar seemed to behave exactly the same way in response to the other white dwarf's gravity.
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A white dwarf is a tiny, dense remnant of the core of a star, about the mass of the sun but the size of Earth.
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"First of all, [these results show] that white dwarf mergers happen," study co-author Götz Gräfener, an astronomer at the University of Bonn told Gizmodo.
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One of the stars is a red giant and the other a white dwarf, with the latter feeding off the former as they move around.
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And more importantly, scientists have directly measured a single white dwarf star's mass without the help of another star or another model of some kind.
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According to the science of quantum mechanics, there are forces within the very atoms of the white dwarf star that counteract the force of gravity.
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Astronomers used the Hubble Space Telescope to measure the mass of a nearby white dwarf, as it bent the light of a more distant star.
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White dwarf stars are essentially the dead remains of stars like our sun, once they've burned through all of their hydrogen fuel and outer layers.
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But this failed supernova has its own unique story to tell, revealing how massive white dwarf stars can become and survive to tell the tale.
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Around the year 2083, its accretion rate will rise catastrophically, spilling mass at incredibly high rates onto the white dwarf, with this material blazing away.
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If general relativity is wrong, then the neutron star would behave differently from its nearby white dwarf companion in reaction to the distant white dwarf's gravity.
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The research team found that once V1213 Centauri exploded, the mass that was transferred from the large companion star to the white dwarf was much higher.
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According to the studies, these elements would end up on the surface of the star when the white dwarf vaporizes small portions of the giant planet.
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Alternative-gravity theories assume that the scalar field generated in the pulsar should bend space-time in a much more extreme way than the white dwarf does.
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They used the data and the relatively simple lensing equation to determine the mass, which aligned nicely with other white dwarf predictions and measurements with other methods.
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"One could argue this is the most model-independent mass measurement for a single white dwarf," meaning this technique doesn't use assumptions from other fields or observations.
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They determined that Stein 2051 B — the sixth-closest white dwarf star to the sun — has a mass that is about two-thirds that of the sun.
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One of those surprises included the unexpected finding of a white dwarf star that's draining the life from its brown dwarf companion, according to a new study.
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The team used this subtle time delay to estimate the mass of the white dwarf, which in turn enabled them to calculate the mass of the pulsar.
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Models show that these supernovae come from a pair of stars in which one, a white dwarf, sucks up a lot of mass from the other before exploding.
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So, they&aposre very different objects — but they should be pulled by the outer white dwarf in the same way if the equivalence principle is on the money.
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A new study published Wednesday in the journal Nature claims to reveal the first evidence that white dwarf stars form solid, crystal cores containing metallic oxygen and carbon.
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The white dwarf is so dense that it sucks hydrogen off the other star, building up a layer of gas that eventually blows outward like a giant bomb.
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The stars weren't exactly aligned, but they were close enough that the white dwarf made it seem like the background star performed a small loop in the sky.
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Artist's impression of the exotic binary system AR Scorpii, with a compact white dwarf star (right) flogging its red dwarf companion with high energy electrons every two minutes.
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As the white dwarf twirls about, these energized particles whip through space, lashing the the cooler companion and releasing a powerful pulse of electromagnetic radiation every 1.97 minutes.
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The big picture: The planetary fragment, known as a planetesimal, orbits within a disc of gas and dust — the remnants of other, destroyed planets — surrounding the white dwarf.
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If the new team was dealing with this scenario, surely the white dwarf would let out a lot of high-energy radiation like ultraviolet light and x-rays.
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The researchers think there could be multiple rings around the white dwarf, and followup observations using missions like the James Webb Space Telescope could help them learn more.
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Some of these worlds may end up hurtling toward the star's posthumous white dwarf, which tears them apart over the course of about 100,000 to one million years.
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In what researchers called "one of those chance discoveries," they found an ice giant exoplanet -- a planet outside of our solar system -- orbiting an Earth-sized white dwarf.
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The Swift telescope may have already spotted an interaction between an intermediate-mass black hole and a white dwarf in the form of a gamma-ray burst called GRB060218.
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Until very recently, the leading theory for standard candle supernovae included a white dwarf—the dying embers of a Sun-like star—that was feeding off of a companion.
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The hot white dwarf is left behind, and any planets and asteroids that survived move farther out because the star no longer has the same gravitational pull on them.
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"Whenever a body comes really close to it, a white dwarf will completely shred it and that dust and debris will fall and accrete onto the star," Doyle explained.
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Farihi's article,"Circumstellar Debris and Pollution at White Dwarf Stars," came out this month in New Astronomy Reviews, and you can read it online as a freely accessible PDF.
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If a star is less than 1.4 times the mass of our Sun, it will collapse into something called a white dwarf — the extremely hot and dense leftover stellar core.
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Why it matters: One day, billions of years from now, our sun will run out of fuel, first becoming a red giant and then collapsing into a white dwarf itself.
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But they quickly found evidence a comet-like object had wandered too close to the white dwarf, and was in the midst of getting ripped apart by the star's gravity.
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These types of supernovas are thought to come from the explosions of white dwarf stars — the dead remnants of a sun-like star — in a binary system with another star.
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"As far as I can tell, the white dwarf merger interpretation meshes well with the observations," Josiah Schwab, a theoretical astrophysicist at UC Santa Cruz, told Gizmodo in an email.
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For the creators of Kurzgesagt (In a Nutshell), a YouTube channel that tackles complex topics with "optimistic nihilism," the answer is to find ourselves a nice stable white dwarf system.
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SN 1572's type Ia supernova appearance implies that it could have come from a smaller white dwarf sucking gas from a large, nearby older star until it blew up.
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But by the time Andromeda approaches, "our sun will have become a white dwarf and bye bye life on Earth," Didier Queloz, a physicist and Nobel laureate, said on Twitter.
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The pulsar has a companion star that scientists think is a white dwarf, another type of stellar corpse that is not quite so dense as neutron stars or black holes.
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These conditions are met in white dwarf stars, which are the remnants of stars that have exploded in supernova and collapsed into super-dense spheres about the size of Earth.
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Specifically, they were analyzing white dwarf stars within NGC 6752 to measure the age of the cluster, which is located approximately 17,000 light-years from the center of the Milky Way.
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But new research published in Nature has revealed that AR Scorpii is actually made up of two stars: A white dwarf and red dwarf that orbit each other every 3.6 hours.
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Read More: Watch This White Dwarf Mercilessly Wail On Its Red Dwarf Friend Of course, even if humans were to migrate to these dwarf systems, it would only prolong the inevitable.
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Alexander Wolszczan and Dimitri Veras, the scientists who made this discovery, next want to point huge telescopes at white dwarf stars to listen for the radio broadcasts of undiscovered dead planets.
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And in a spectacular discovery, a volunteer citizen scientist working with a NASA project has found the coldest, oldest-known white dwarf, and it's surrounded by rings of dust and debris.
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In the final days of this death-spiral, all of the mass from the companion star will fall onto the white dwarf, creating a super-massive wind from the merging star.
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There are approximately 100 billion stars in the Milky Way — each one a massive ball of hydrogen and helium burning until it eventually becomes a white dwarf or explodes in a supernova.
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But if a star is more than 1.4 times the mass of our Sun, it won't form a white dwarf but instead explode in a supernova or collapse into a black hole.
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In other words, if humanity wants to play the cosmic long game, we should cozy up to white dwarf systems to ride this whole sentient existence thing out to the very end.
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Since the planet would have to be relatively close to the star for this to happen, the researchers expect the planet makes a full orbit around the white dwarf in 10 days.
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The pulsar packs 1.4 times the sun&aposs mass into a sphere the size of Amsterdam, whereas the interior white dwarf harbors just 0.2 solar masses and is about the size of Earth.
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In about 10 billion years, our sun is likely to turn into a white dwarf — a shrunken, extremely dense star whose nuclear core has burned out and gotten rid of its outer layers.
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"The unexpected realization that this 1917 plate from our archive contains the earliest recorded evidence of a polluted white dwarf system is just incredible," Carnegie Observatory director John Mulchaey said in a statement.
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Williams et al; Optical: DSS; Radio: NSF/NRAO/VLAAstronomers have used 15 years of X-ray data to make this video of the remnants of a white dwarf that famously exploded in 1572.
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It is the first time the transition of a white dwarf star with a low and unstable mass-transfer rate to a classical nova eruption has been observed, study author Przemek Mróz said.
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Check out this mesmerizing animation of the binary star system AR Scorpii, in which a white dwarf repeatedly thrashes its red dwarf partner with jets of radiation, causing regular pulses every 1.97 minutes.
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The data revealed an event, from the initial hours it began and the 30-day period as it unfolded, of intense brightening in a system including a white dwarf and a brown dwarf.
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Some that star stuff was dumped onto the white dwarf, which turbocharged its spin to a period of about three minutes, as opposed to the hour-scale day of more typical white dwarfs.
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The star, known as WD J0914+1914, is one of 10,000 white dwarf stars observed during the Sloan Digital Sky Survey, a project that created the most detailed 3D map of the universe.
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The theory that white dwarf cores turn into a solid crystal was first proposed over 50 years ago, but it wasn't until recently that astronomers had the data they needed to verify this prediction.
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In 2014, a group of astronomers using NASA's Hubble Space Telescope spotted a rare type of microlensing, when a dense white dwarf star passed in front of another star thousands of light-years away.
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We've seen many examples of a type of system where one white dwarf has been mostly cannibalized by its companion, but we rarely catch these systems as they are still merging like this one.
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Such debris disks were typically understood to be the remains of a small body, such as an asteroid or comet, that had come near the white dwarf and been torn apart by tidal forces.
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The researchers also believe the radiation may also evaporate Jupiter, Saturn, Uranus and Neptune, with only atmospheric gases pulled around the white dwarf for any potential intelligent life to learn about our solar system.
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A classical nova occurs when a white dwarf star gains matter from its secondary star over a period of time, causing a thermonuclear reaction on the surface that eventually erupts in a single visible outburst.
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Using this data, the researchers found that one particular white dwarf, with the eloquent name SDSS J124043.01+671034.68, didn't have any hydrogen or helium in its atmosphere; its surrounding air was instead almost pure oxygen.
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"For a core to have reached that stage, it would have been violently stripped of its atmosphere and mantle at some point and then thrown towards the white dwarf," Veras said in the press release.
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They make some awe-inspiring discoveries: a star-sized diamond in one system might be a data storage artifact, while another system contains a white dwarf, just on the brink of collapsing into a black hole.
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Then, they can investigate more about the little instigator that disturbed its sleepy white dwarf star companion and heaped enough matter on its surface to cause a blinding temper tantrum in their corner of the universe.
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By measuring just how much the light from the background star was distorted by Stein 2051B, the researchers were able to figure out that the white dwarf is about 68 percent the mass of our sun.
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The details: Einstein predicted a ray of light passing near a massive star like a white dwarf to be deflected by twice the amount that would ordinarily be expected based on what we know of gravity.
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"Nobody has ever found just the bare core of a major planet before, nor a major planet only through monitoring magnetic signatures, nor a major planet around a white dwarf," Wolszczan said in a press release.
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The astronomers began to question if the unusual, ultra-massive white dwarf was more than one star, especially due to the puzzling amounts of hydrogen and carbon they detected -- likely from two stars, rather than one.
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The main star in the system inflated as it burned through its hydrogen stores and became a red giant, one of the last phases of stellar evolution before the star dies and becomes a white dwarf.
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That enabled them to witness a gradual drift in the system's orbital plane of 0.0004 degrees per year, which this study confirmed is due to frame-dragging generated by the dizzying spin of the white dwarf.
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This is a type of explosion caused by an ordinary star similar to our Sun and a white dwarf — a small, super-dense stellar corpse left over when a regular star uses up all its nuclear fuel.
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A fragment of a planet orbiting a white dwarf star 400 light-years away gives scientists a rare glimpse into the death of a solar system, according to a new study published in the journal Science Thursday.
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Image: NASA, ESA, and Z. Levy (STScI)Here's your daily reminder that the final frontier is ruthless: For the first time ever, scientists have spotted a comet-like object getting torn apart by a white dwarf star.
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Clarification: A previous version of this article said that the white dwarf binary system could fit within our solar system; more accurately, the binary could fit within the diameter of the planet Saturn, according to the paper.
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Potential explanations for fast radio bursts include magnetars (rapidly spinning neutron stars), neutron star-white dwarf mergers, collapsed stars, black holes, and—very much in last place in terms of evidence—some kind of artificial, extraterrestrial source.
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She explained that one kind of white dwarf-containing explosive-but-not-supernova-explosive stellar binary called "recurrent novae" are only detectable as these kinds of radiation sources for a short period of time after small eruptions.
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Image: NASA, ESA and A. Feild (StSci)"The fact that we could actually measure the mass of a white dwarf is exciting," the paper's lead author, astronomer Kailash Sahu from the Space Telescope Science Institute, told Gizmodo.
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"It looks like the white dwarf pushed it out of the way," Terry Oswalt, an astronomer at Embry-Riddle Aeronautical University who was not involved in this discovery but wrote a perspective piece in Science, tells The Verge.
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AR Scorpii, previously identified as a single, variable star, is actually two, a compact white dwarf the size of the Earth but 200,000 times more massive, and a cool red dwarf a third the size of the Sun.
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The hourglass shape (it really doesn't look like a crab to us) was made by two stars that had been swirling around each other—one a dead white dwarf star and the other a very old red dwarf.
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In the new study, astronomers were able to pinpoint a moment in time when a white dwarf star and a second star were being observed in such a fashion that lensing could be seen for the first time.
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This causes the white dwarf to burn up to 100 times more brightly than normal, making it visible on Earth with the naked eye, and creating a new star in the sky as bright as Polaris—the north star.
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"Tidal disruptions of white dwarf stars by intermediate-mass black holes are complex and violent cosmic events capable of generating significant electromagnetic and potentially observable gravitational wave energies," the authors write in the study accepted for publication in The Astrophysical Journal.
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This 400 by 900 light-year mosaic of several Chandra images of the central region of our Milky Way galaxy reveals hundreds of white dwarf stars, neutron stars, and black holes bathed in an incandescent fog of multimillion-degree gas.
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What they did: Astronomers from the University of Warwick in the U.K. used observations from the European Space Agency's Gaia satellite to examine the luminosities and colors from about 15,000 white dwarf candidates within about 300 light-years of Earth.
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By examining the system with the Very Large Telescope at the European Southern Observatory, the Hubble Space Telescope and others, astronomers have now learned that the white dwarf is spinning incredibly fast, charging up electrons to almost the speed of light.
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The star system in question—V1213 Cen, located 23,000 light years away in the Scutum–Centaurus arm of the Milky Way—consists of two close-knit companions, a dim red dwarf and a dead stellar core known as a white dwarf.
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It all started about a year ago, when Jay Farihi of the University College London contacted the Carnegie Observatory about a glass plate containing a spectrum of van Maanen's star, a white dwarf photographed by renowned astronomer Walter Adams in 1917.
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When the white dwarf passes in front of the pulsar, it appears to causes a slight delay in the pulsing, because the light must travel a slightly longer path as the white dwarf's gravity slightly warps the shape of space.
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Some astronomers think these types of explosions are triggered when a white dwarf eats up a large amount of the material from its companion in the binary, but another hypothesis suggests the explosion occurs when 2 white dwarfs slam into each other.
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This change in the flow of hydrogen before and after a classical nova has been predicted but never seen directly before.. Scientists think it takes maybe millions of years before a white dwarf accumulates enough hydrogen to explode in a classical nova.
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With each passing day this core, known as a white dwarf, will cool and fade hopelessly out of existence (into a cold black dwarf), as if it didn't once host the most lively planet ever discovered in the sweeping canvas of the universe.
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In a shard of galactic archaeology that offers a less-than-inviting hint at our own future, astronomers have discovered a chunk of a former planet orbiting the remains of its former star, now a smoldering cinder known as a white dwarf.
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"The brown dwarf was effectively hidden by the dust until we looked with the right instrument, but when we observed SDSS 1557 in detail we recognised the brown dwarf's subtle gravitational pull on the white dwarf," study co-author Steven Parsons said in the statement.
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The term "zombie" has been applied to a few different types of star systems, but the most well-known scenario involves a low-mass white dwarf star exploding in a Type Iax supernova, which means that the star survives what is normally a fatal blast.
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The researchers believe the merger likely occurred 1.3 billion years ago, meaning both stars could have existed for billions of years before their merger It's only one of a few merged white dwarf star pairs ever known, and the only one with this particular composition.
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A new way of studying planets in other solar systems — by doing sort of an autopsy on planetary wreckage devoured by a type of star called a white dwarf — is showing that rocky worlds with geochemistry similar to Earth may be quite common in the cosmos.
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Any life that might have evolved on planets orbiting the star would have been vaporized as it died, leaving behind only its white dwarf shell, with its searing temperatures of 360,000 degrees Fahrenheit (200,000 degrees Celsius), and a surrounding cloud of kicked up dust and gas.
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Dr. Manser, along with Boris Gänsicke, also at the University of Warwick, has been studying the disc around a white dwarf known as SDSS J122859.93+10432.9; they have used a variety of telescopes, most recently the Gran Telescopio Canarias in La Palma, in Spain's Canary Islands.
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To confirm that the unusual element was not just a mistake in the data, Gänsicke and his collaborators recorded another spectrum of the white dwarf with the world's most advanced optical telescopes in Chile, called (and you can't make this up, folks) the Very Large Telescope array.
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Located 55 million light years away in a spiral galaxy called NGC 5643, SN 2017cbv was spotted almost immediately after it erupted from a white dwarf into a supernova, allowing scientists to monitor the fallout of the blast, and the subsequent smash with its companion star.
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Scientists have observed these binaries with a high level of mass transferred from the companion star to the white dwarf—all but one of the novae observed in the 20th and 21st century are in this state currently, said Mróz, including the nova he observed and published last year.
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"This is a potential explanation for an unusual type of 'transient' or temporary source—one that appears and then disappears—which contains substantial amounts of calcium, but not so much iron or nickel, as we might expect in a 'typical' white dwarf generated supernova (Type Ia supernovae)," she wrote.
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The explosion that formed DEM L316A was an example of an especially energetic and bright variety of supernova, known as a Type Ia. Such supernova events are thought to occur when a white dwarf star steals more material than it can handle from a nearby companion, and becomes unbalanced.
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The paradoxical work brings us the world's first laser-cooled neutral plasma, which researchers hope will allow physicists to study some of the most exotic matter in the universe, such as the dense gases found in white dwarf stars, as well as make progress in fusion energy research.
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WASHINGTON (Reuters) - A new way of studying planets in other solar systems - by doing sort of an autopsy on planetary wreckage devoured by a type of star called a white dwarf - is showing that rocky worlds with geochemistry similar to Earth may be quite common in the cosmos.
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According to a team of astronomers whose research will be published in a forthcoming issue of Monthly Notices of the Royal Astronomical Society, there's also a chance that the Cow event was a massive black hole ripping apart a white dwarf star—an astronomical event known as a tidal disruption.
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This isn't the first time scientists have measured the mass of a white dwarf either, but other methods usually require some theoretical model and other measurements or a much closer binary system than this one, astronomer Pier-Emmanuel Tremblay from the University of Warwick in the United Kingdom told Gizmodo.
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Made up of a Sun-scale orange dwarf (Eridani A), a white dwarf (Eridani B), and a red dwarf (Eridani C), this system was selected to be "Vulcan's Sun" after Star Trek creator Gene Roddenberry consulted with astronomers Sallie Baliunas, Robert Donahue, and George Nassiopoulos about the best location for the fictional planet.
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Plasma is usually produced in extremely high temperature environments, such as the surface of the Sun, but in even more extreme environments (like at the center of an ultra-dense white dwarf star or Jupiter) plasma begins to behave in unusual ways that are difficult to replicate in a lab on Earth.
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"Although these signals fall within LISA's frequency band, the amplitudes are sufficiently small that they will not likely be observed except at source distances within [around 33,000 to 333,000 light years], which, if current estimates of the [white dwarf to intermediate-mass black hole] disruption rate... are correct, would be extremely rare events," the authors write in the paper.
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Based on the first discovery of a giant planet orbiting a white dwarf, reported in two new papers in the journals Nature and Astrophysical Journal Letters, researchers now believe that this hypothetical alien would be able to observe signatures of our Solar System's largest planets—Jupiter, Saturn, Uranus, and Neptune—just by looking at the dead Sun.
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The study's "measurements show convincingly that Stein 2051 B is not an exotic 'iron core' white dwarf but a rather typical one, with a carbon-oxygen core and a normal mass and radius, thus resolving the long-standing debate over its nature," scientist T.D. Oswalt, who was not involved with the new study, said in an analysis piece published with the new work.
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This part of Einstein's prediction is called 'astrometric lensing' and Sahu's team was the first to observe it in a star other than the sun … Sahu's team measured shifts in the apparent position of a distant star as its light was deflected around a nearby white dwarf star called Stein 2051 B on eight dates between October 2013 and October 2015.
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Scientists have subsequently theorized that they're the glowing remnant of a gamma-ray burst (a massive explosion produced by a collapsing star that gives birth to a black hole), a supernova fueled by a magnetar (a neutron star with a powerful magnetic field), or a failed Type Ia supernova (in which a white dwarf star sucks up material from a nearby star, eventually causing it to explode).
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Provided humans survive our own self-destructive tendencies, the Earth's atmosphere could have another billion years, and the Sun maybe 7 billion to 10 billion years before it grows into a red giant, ejects its outer layers, and remains just a glowing core around the same size as the Earth but packing far more mass, called a white dwarf, according to John Baez, a physicist at University of California, Riverside.
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Red dwarfs also present a promising long-term option, but because they are thought to be more flare-happy than white dwarfs, it may be more of a gamble to set up shop next to them We would probably have to bring our own planetary hardware, since any life-bearing worlds in white dwarf systems are likely to have been eviscerated by the deaths of the original stars, but we still have a few billion years left on Earth to work out these logistics.
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