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[Music throughout] Scientists used supercomputer simulations

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to throw eight different types of stars at a monster black hole.

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Their goal is to create more realistic models of 

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tidal disruption events, which occur when unlucky stars stray

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too close to black holes. Gravitational forces create intense

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tides that deform the stars and break them into streams of gas.

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These simulations are the first to combine the 

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physical effects of Einstein’s general theory of relativity and

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virtual stars with realistic internal structures.

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This schematic shows the stars’ trajectory. In this

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version of the simulations, the black hole has 1 million times the Sun’s mass

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and the stars are about 24 million miles away at their

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closest. The model stars range from about

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one-tenth to 10 times the Sun’s mass. The colors reflect

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their densities, from the lowest, shown in blue, to the highest,

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in yellow.

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In some cases,

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the stars are fully pulled apart. In others,

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they’re only partially disrupted. As these

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stars move farther from the black hole, their own gravity pulls them

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back together. Surprisingly, the stars that fully

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and partially disrupt aren’t cleanly divided by mass.

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The Sun-like star, along with those with 0.15, 

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0.3, and 0.7 solar masses, survive

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their close encounters. But stars with 0.4, 

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0.5, 3, and 10 times the Sun’s mass are

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completely torn apart. The difference between

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survival and destruction depends on the star’s internal density.

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Simulations like these

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will help astronomers build a better picture of these catastrophic events

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occurring in galaxies millions of light-years away.

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[NASA]

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[NASA]