I will report on my recent projects about tide and magnetic field of celestial bodies such as star, exoplanet and exomoon. The projects are as follows. (1) stellar magnetic dynamo: field-rotation relation in anisotropic rotating turbulence; (2) stellar oblique rotator: why solar radiative zone is in uniform rotation; (3) stellar wave transmission: can internal waves transmit at the interface of radiative and convective zones; (4) magnetic tide: ohmic dissipation needs to be taken into account for orbital evolution; (5) tidal resonance: the resonance of tidal wave and orbital motion; (6) exoplanet's inflation: radius anomaly of hot Jupiters; (7) exomoon's retention: where to detect exomoons.
