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Name: Lydia
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Why do planets exist?

WHY? Is NOT a question that science answers very well. HOW? IS a question science deals with very well. Planets form when the dust rocks and gases surrounding a star begin to clump together. If there isn't enough dust rocks and gases to form another star by the heat generated by gravity pulling the "stuff" together, one of the things that can happen if the formation of planets. Other things can happen, such as the formation of comets, belts around the star, to mention only two. This deals with the "how" question, but not with the "why" question?

The answer to the "why" question depends upon ones philosophical and/or religious perspective. But those questions, science has little to offer.

Vince Calder


We are only truly beginning to understand solar system evolution, but this is what we our data suggests so far: (1) Interstellar dust (possibly from a star that went nova) naturally accrete - they bump into each other and due to a lack of any other forces their electrostatic forces make them come together and form clumps. (2) These clumps start to exert a gravitational force causing (a) more dust to collect, and (b) impart a rotational force to the whole interstellar gas system. (3) a massive center forms and this becomes a star when enough matter collect on it, (4) The birth of a star blows out excess matter which will in turn swirl around the gravitational center of the new star. (5) These excess matter will collect on their own and form planets. Some of them will become gas giants (like Jupiter, Saturn) and others will be rocky (Mars, Earth). (6) In turn, these planetary centers may capture other planetoids and make them moons.

Greg (Roberto Gregorius)

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