Proposed sources of such high heating in the early solar nebula have included everything from colliding asteroids, gamma ray bursts, solar x-ray flares, even lightning in the proto-planetary disk itself.

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Mr. EICHER: We can't really understand the solar system and how it got going unless we can really understand the origins and the conditions that happened when the solar nebula, this cloud of gas and dust, contracted down and the star turned on and the planets got going.

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It describes a life form that inhabits a small nebula known as a Bok globule, which visits the solar system to refuel from the sun.

ECONOMIST: Sir Fred Hoyle