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Name: Patrick
Status: student
Grade: 9-12
Location: Outside U.S.
Country: USA
Date: April  2011

Is it possible that some planets could have formed before the sun ignited?

Yes, it is possible, but unlikely. The planets in our solar system began to accrete from dust left over from the Sun's ignition, after the Sun ignited.

Sincerely, David Levy


A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighboring region of planetesimals.

So no. The definition we have assigned to the word "planet" requires a star to orbit around.

See the following URL for amplification:

Sincere regards, Mike Stewart

The general consensus is that stars form prior to their attendant planets. So while prior planets could form (as far as I know that does not violate any physical laws) to my knowledge such reverse formation has not been observed.

Vince Calder

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