Pulsating star changes to cylinder, portal shape, late afternoon, Aptos, CAAppearance: I initially saw in the sky, what appeared to be a bright star.Within seconds it began pulsating and seemed to send an energy wave at me. My dog was going crazy and my internal alarm went off and said RUN! I quickly ran inside to get my camera, came back outside and saw it change into a cylindrical shape - top and bottom, bright white and slightly larger than the middle, which was a more transparent white.