Department of Energy Argonne National Laboratory Office of Science NEWTON's Homepage NEWTON's Homepage
NEWTON, Ask A Scientist!
NEWTON Home Page NEWTON Teachers Visit Our Archives Ask A Question How To Ask A Question Question of the Week Our Expert Scientists Volunteer at NEWTON! Frequently Asked Questions Referencing NEWTON About NEWTON About Ask A Scientist Education At Argonne Planet Formation Before Solar Formation 

Name: Patrick
Status: student
Grade: 9-12
Location: Outside U.S.
Country: USA
Date: April  2011
Question:
Is it possible that some planets could have formed before the sun ignited?


Replies:
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

Patrick

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:

http://en.wikipedia.org/wiki/Planet

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


Click here to return to the Astronomy Archives

NEWTON is an electronic community for Science, Math, and Computer Science K-12 Educators, sponsored and operated by Argonne National Laboratory's Educational Programs, Andrew Skipor, Ph.D., Head of Educational Programs.

For assistance with NEWTON contact a System Operator (help@newton.dep.anl.gov), or at Argonne's Educational Programs

NEWTON AND ASK A SCIENTIST
Educational Programs
Building 360
9700 S. Cass Ave.
Argonne, Illinois
60439-4845, USA
Update: June 2012
Weclome To Newton

Argonne National Laboratory