Lindblad resonance

Phenomenon in astrophysics

A Lindblad resonance, named for the Swedish galactic astronomer Bertil Lindblad, is an orbital resonance in which an object's epicyclic frequency is a simple multiple of some forcing frequency. Resonances of this kind tend to increase the object's orbital eccentricity and to cause its longitude of periapse to line up in phase with the forcing. Lindblad resonances drive spiral density waves both in galaxies and in Saturn's rings.

This keyword could refer to multiple things. Here are some suggestions: