Changes

A '''planet''' is a astronomical body that is in [[orbit]] around the [[Sun]], has sufficient mass for its own [[gravity]] to overcome rigid body forces so that it assumes a nearly round shape, and has cleared the neighborhood around its orbit <ref>http://www.iau.org/iau0603.414.0.html</ref>.

A '''planet''' is a astronomical body that is in [[orbit]] around a [[star]], has sufficient mass for its own [[gravity]] to overcome rigid body forces so that it assumes a nearly round shape, and has cleared the neighborhood around its orbit <ref>http://www.iau.org/iau0603.414.0.html</ref>.

The phrase "cleared the neighborhood around its orbit" refers to a body "sweeping out" the area around its orbit as it forms, by causing all other smaller bodies in its orbit to accrete with it. As a consequence it does not then share its orbital region with any other bodies of significant size, except for satellites or those collected later under its gravitational influence.  

The phrase "cleared the neighborhood around its orbit" refers to a body "sweeping out" the area around its orbit as it forms, by causing all other smaller bodies in its orbit to accrete with it. As a consequence it does not then share its orbital region with any other bodies of significant size, except for satellites or those collected later under its gravitational influence.