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When a star like our Sun begins to die, it
expands into a bloated red giant star, shedding

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mass by puffing off its outer layers.

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This change alters the gravitational influence
the star has on its planetary system.

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The gravity of the remaining large planets
can disrupt the orbits of small objects like

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asteroids, comets, and moons, scattering them
like pinballs in an arcade game into exaggerated

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oval orbits.

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As the red giant star runs out of its nuclear
fuel, it begins to contract, creating a compact

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white dwarf star no larger than Earth.

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The exaggerated orbits of the wayward objects
may bring them very close to the star where

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they experience powerful tidal forces that
tear them apart, creating a gas and dust disk

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around the white dwarf that eventually falls
onto the star’s surface.

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Five billion years from now when our Sun is
at the end of its life, Mercury, Venus, and

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Earth will likely be completely vaporized
as the Sun becomes a red giant.

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The orbits of asteroids in the main asteroid
belt will be altered, eventually falling onto

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the white dwarf that our Sun will become.

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This scenario is exactly what is happening
to a nearby white dwarf star named G238-44.

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The star's death throes have so violently
disrupted its planetary system that it is

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actively siphoning off debris from both the
system’s inner and outer reaches.

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Using archival data from Hubble and other
NASA space observatories, astronomers have

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for the first time observed a white dwarf
star consuming both rocky-metallic and icy

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material.

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The findings are intriguing because icy bodies
are credited with irrigating dry, rocky planets.

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Billions of years ago comets and asteroids
are thought to have hit our planet, delivering

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water – and sparking the conditions necessary
for life as we know it.

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The makeup of the bodies raining onto the
white dwarf implies that icy reservoirs might

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be common among planetary systems.

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This white dwarf provides a unique opportunity
to take distant planets apart and see what

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they were made of when they first formed around
the star, letting us better understand what

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makes up star systems besides our own.