[RationPhantoms]

Same physics principles used to measure gravitational waves at LIGO (Laser Interferometer Gravitational-Wave Observatory)but just much, much smaller. Very neat!

[mturmon]

Michelson interferometry is also used to measure the spatially-resolved velocity and magnetic field of the solar photosphere: https://en.wikipedia.org/wiki/Solar_Dynamics_Observatory -> Instruments

[LolWolf]

thanks !