Kenneth Chang

@DrFunkySpoon Well, yeah, Twitter is not the medium for precisely caveated statements. Who has proposed a good definition of planet?

@kchangnyt @DrFunkySpoon http://arxiv.org/abs/1507.06300  ?

@astrokiwi @kchangnyt Here's one stab at it that I made: http://funkyscience.net/wp-content/uploads/2013/07/PlanetDef_Aug.pdf …

@DrFunkySpoon @astrokiwi No way to prove roundness of exoplanets, right?

@kchangnyt @astrokiwi In general not observationally. But know mass & density. Above a certain size, physics kicks in.

@DrFunkySpoon @astrokiwi Then it’s a fuzzy, arbitrary mass cutoff. Something slightly smaller still roundish (e.g. Vesta).

@DrFunkySpoon @astrokiwi Composition also influences whether it can become round.

@kchangnyt @astrokiwi True but we often have constraints on density. What we will never know is small body population in vicinity of exos.