Similar question, inspired by ancient Egyptians & Romans: The definition of a planet(oid) seems to be a body large enough to force itself into a nearly spherical shape. Suppose you wanted to hack this defn. What weird shape could you build out of standard materials (bricks, cement, steel, carbon fiber?) that would have the same mass as a real planet but retain its weird shape. Alternatively, assuming the exact same recipe of elements as found in the entire Earth, how big of an object could be built that retained its shape under a) self gravity; and b) rotational stresses; and b) the various tidal forces due to the Moon, planets, Sun. Fractal structures aren't so farr-fetched: http://www.london-institute.org/people/farr/fractals.shtml At 10:23 AM 7/20/2015, Bill Gosper wrote:
Maybe one of the deviations from sphericity of https://en.wikipedia.org/wiki/21_Lutetia ? How would you rule it out? Related: An earth-size cube of "solid" rock would immediately collapse to a sphere with eight mountains. About how tall? Maybe mountains should be ranked by gravitational potential energy. --rwg