# Did Mercury clear its neighborhood?

For a body to qualify as a planet according to the IAU definition it must have "cleared its neighborhood". What evidence is there Mercury indeed cleared its neighborhood? Perhaps it migrated there afterwards, when the neighborhood had already been cleared. Does the Grand Tack hypothesis impact our definition of the inner planets as planets?

https://en.m.wikipedia.org/wiki/IAU_definition_of_planet

The present definition of a planet is vulnerable as it seems connected to a model of formation of the solar system. The answer below states that in practice an operational definition used that I believe is adequate.

• Can you explain that the "Grand Tack Hypothesis" is? – fasterthanlight Nov 15 '20 at 13:17
• If we take the 2006 definition literally (which seemingly noone does) no planet 'cleared its neighbourhood'. en.wikipedia.org/wiki/List_of_Mercury-crossing_minor_planets – John Nov 15 '20 at 13:59
• That's because the IAU are scientists not lawyers. – James K Nov 15 '20 at 16:38
• @JamesK Scientists could have easily come up with a definition that would exclude Pluto, include 8 planets, and not state anything different or contradictory. – John Nov 15 '20 at 17:02
• I know. They did. – James K Nov 15 '20 at 17:23

• -1 because all the "we call" and "we don't look" language is unsupported with authoritative sources. In Stack Exchange we supply information, we do not generate it ourselves. We are not the authority here. We are merely a service provider. Currently there is no way to tell if this is authoritative and correct or purely guesswork because you don't cite any supporting sources. This is Stack Exchange not Quora. – uhoh Nov 17 '20 at 3:41