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when a star like our sun begins to die

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it expands into a bloated red giant star

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shedding mass by puffing off its outer

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layers

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this change alters the gravitational

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influence the star has on its planetary

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system the gravity of the remaining

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large planets can disrupt the orbits of

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small objects like asteroids comets and

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moons scattering them like pinballs in

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an arcade game into exaggerated oval

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orbits

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as the red giant star runs out of its

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nuclear fuel it begins to contract

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creating a compact white dwarf star no

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larger than earth

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the exaggerated orbits of the wayward

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objects may bring them very close to the

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star where they experience powerful

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tidal forces that tear them apart

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creating a gas and dust disk around the

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white dwarf that eventually falls onto

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the star's surface

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five billion years from now when our sun

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is at the end of its life

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mercury venus and earth will likely be

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completely vaporized as the sun becomes

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a red giant

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the orbits of asteroids in the main

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asteroid belt will be altered eventually

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falling onto the white dwarf that our

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sun will become

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this scenario is exactly what is

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happening to a nearby white dwarf star

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named

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g23844 the star's death throws have so

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violently disrupted its planetary system

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that it is actively siphoning off debris

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from both the system's inner and outer

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reaches

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using archival data from hubble and

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other nasa space observatories

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astronomers have for the first time

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observed a white dwarf star consuming

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both rocky metallic and icy material

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the findings are intriguing because icy

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bodies are credited with irrigating dry

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rocky planets billions of years ago

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comets and asteroids are thought to have

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hit our planet delivering water and

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sparking the conditions necessary for

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life as we know it

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the makeup of the bodies raining onto

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the white dwarf implies that icy

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reservoirs might be common among

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planetary systems

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this white dwarf provides a unique

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opportunity to take distant planets

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apart and see what they were made of

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when they were first formed around the

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star

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letting us better understand what makes