Actually, sounds like they mention both.

"The furthest planet in the new system orbits just inside a disk of dusty debris, similar to that produced by the comets of the Kuiper belt of our solar system (just beyond the orbit of Neptune at 30 times Earth-sun distance)."

"HR 8799's dust disk stands out as one of the most massive in orbit around any star within 300 light years of Earth," said UCLA'S Ben Zuckerman."

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"In the end the aggressors always destroy themselves, making way for others who know how to cooperate and get along. Life is much less a competitive struggle for survival than a triumph of cooperation and creativity."- Fritjof Capra

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