This image shows the electronís probability density distribution for an atom in the state; n=4, l=4, m=0. A small, dense nucleus would reside at the center of the "propeller". Note the jet-like structures extending from the center.

     The star Eta Carina is ejecting a pair of huge lobes that form a "propeller" shape. Jet-like structures are emanating from the center (or "waist"), where the star (quite small on this scale) is located.

Source: H.E. White, Physical Review, vol. 37, pg. 1423, 1931. Source: