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using nasa's spitzer space telescope

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we've looked at many nearby stars to

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look for orbiting

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dust and asteroids and comets orbiting

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debris left over from the process of

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planet formation

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we saw something very unusual that we

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hadn't seen around any other star

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we saw evidence for a massive collision

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when the two objects collide

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everything happens very quickly in the

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animation things have been slowed down

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to allow you to see

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the impacting shock wave propagate

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across the surface of this devastated

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starting from the point of impact and

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circulating to the backside

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causing waves on the surface

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the entire planet becomes molten

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meanwhile tremendous amounts of material

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are ejected from the planet both outside

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of the system and some falls back onto

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the system itself depending on the

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details of the collision whether it's a

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high impact or depending on the angle

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that the objects hit each other at

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the there may be a growth or there may

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be a grinding away so sometimes the

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planet actually ends up smaller after

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the collision but generally the planet

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grows to larger and larger until there's

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no more material left in the system for

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while collisions like this are rare we

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don't see this large event in any other

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systems we've looked at with the spitzer

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space telescope

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collisions like this have happened in

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our own solar system so there was a

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large collision that formed our own moon

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early on as our planets formed similarly